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Sample records for temperature pyrolysis deoxygen

  1. Methods for deoxygenating biomass-derived pyrolysis oil

    Energy Technology Data Exchange (ETDEWEB)

    Baird, Lance Awender; Brandvold, Timothy A.

    2015-06-30

    Methods for deoxygenating a biomass-derived pyrolysis oil are provided. A method for deoxygenating a biomass-derived pyrolysis oil comprising the steps of combining a biomass-derived pyrolysis oil stream with a heated low-oxygen-pyoil diluent recycle stream to form a heated diluted pyoil feed stream is provided. The heated diluted pyoil feed stream has a feed temperature of about 150.degree. C. or greater. The heated diluted pyoil feed stream is contacted with a first deoxygenating catalyst in the presence of hydrogen at first hydroprocessing conditions effective to form a low-oxygen biomass-derived pyrolysis oil effluent.

  2. Methods for deoxygenating biomass-derived pyrolysis oil

    Energy Technology Data Exchange (ETDEWEB)

    Brandvold, Timothy A.

    2015-07-14

    Methods for deoxygenating a biomass-derived pyrolysis oil are provided. A method comprising the steps of diluting the biomass-derived pyrolysis oil with a phenolic-containing diluent to form a diluted pyoil-phenolic feed is provided. The diluted pyoil-phenolic feed is contacted with a deoxygenating catalyst in the presence of hydrogen at hydroprocessing conditions effective to form a low-oxygen biomass-derived pyrolysis oil effluent.

  3. Pt/Al?O?-catalytic deoxygenation for upgrading of Leucaena leucocephala-pyrolysis oil.

    Science.gov (United States)

    Payormhorm, Jiraporn; Kangvansaichol, Kunn; Reubroycharoen, Presert; Kuchonthara, Prapan; Hinchiranan, Napida

    2013-07-01

    The aim of this study was to improve the quality of bio-oil produced from the pyrolysis of Leucaena leucocephala trunks via catalytic deoxygenation using Pt/Al2O3 (Pt content=1.32% (w/w)). The minimum molar ratio of oxygen/carbon (O/C) at 0.14 was achieved when the amount of catalyst was 10% (w/w, bio-oil) and was applied under 4 bar of initial nitrogen pressure at 340°C for 1h. The reaction mechanism of the catalytic deoxygenation, in terms of reforming, water-gas shift and dehydration reactions, was proposed. To consider the effect of different biomass types on the efficiency of catalytic deoxygenation, the bio-oils obtained from the pyrolysis of sawdust, rice straw and green microalgae were likewise evaluated for direct comparison. PMID:23648762

  4. Formate assisted pyrolysis of pine sawdust for in-situ oxygen removal and stabilization of bio-oil.

    Science.gov (United States)

    Case, Paige A; Wheeler, M Clayton; DeSisto, William J

    2014-12-01

    Pine sawdust was pretreated with several calcium compounds and then pyrolyzed in a fluidized bed pyrolysis reactor at 500 °C. The catalytic action of the calcium compounds varies depending on the anion. Analysis of pyrolysis gas, liquid and char yields and compositions demonstrates that calcium sulfate is inert during pyrolysis while calcium formate, carbonate, hydroxide and oxide show significant deoxygenation activity. Of the salts which showed deoxygenation activity, calcium formate had the highest relative yield. This effect is likely attributable to the activity of calcium formate as a hydrogen donor at the pyrolysis temperature. PMID:25305646

  5. Effect of temperature on pyrolysis product of empty fruit bunches

    Science.gov (United States)

    Rahman, Aizuddin Abdul; Sulaiman, Fauziah; Abdullah, Nurhayati

    2015-04-01

    Pyrolysis of empty fruit bunches (EFB) was performed in a fixed bed reactor equipped with liquid collecting system. Pyrolysis process was conducted by varying the terminal pyrolysis temperature from 300 to 500°C under heating rate of 10°C/min for at least 2 hours. Char yield was obtained highest at 300°C around 55.88 wt%, and started to decrease as temperature increase. The maximum yield of pyrolysis liquid was obtained around 54.75 wt% as pyrolysis temperature reach 450°C. For gas yield percentage, the yield gained as temperature was increased from 300 to 500°C, within the range between 8.44 to 19.32 wt%. The char obtained at 400°C has great potential as an alternative solid fuel, due to its high heating value of 23.37 MJ/kg, low in volatile matter and ash content which are approximately around 40.32 and 11.12 wt%, respectively. The collected pyrolysis liquid within this temperature range found to have high water content of around 16.15 to 18.20 wt%. The high aqueous fraction seemed to cause the pyrolysis liquid to have low HHV which only ranging from 10.81 to 12.94 MJ/kg. These trends of results showed that necessary enhancement should be employ either on the raw biomass or pyrolysis products in order to approach at least the minimum quality of common hydrocarbon solid or liquid fuel. For energy production, both produced bio-char and pyrolysis liquid are considered as sustainable sources of bio-energy since they contained low amounts of nitrogen and sulphur, which are considered as environmental friendly solid and liquid fuel.

  6. Pressurized pyrolysis of rice husk in an inert gas sweeping fixed-bed reactor with a focus on bio-oil deoxygenation.

    Science.gov (United States)

    Qian, Yangyang; Zhang, Jie; Wang, Jie

    2014-12-01

    The pyrolysis of rice husk was conducted in a fixed-bed reactor with a sweeping nitrogen gas to investigate the effects of pressure on the pyrolytic behaviors. The release rates of main gases during the pyrolysis, the distributions of four products (char, bio-oil, water and gas), the elemental compositions of char, bio-oil and gas, and the typical compounds in bio-oil were determined. It was found that the elevation of pressure from 0.1MPa to 5.0MPa facilitated the dehydration and decarboxylation of bio-oil, and the bio-oils obtained under the elevated pressures had significantly less oxygen and higher calorific value than those obtained under atmospheric pressure. The former bio-oils embraced more acetic acid, phenols and guaiacols. The elevation of pressure increased the formation of CH4 partially via the gas-phase reactions. An attempt is made in this study to clarify "the pure pressure effect" and "the combined effect with residence time". PMID:25463787

  7. Ecotoxicological characterization of biochars: role of feedstock and pyrolysis temperature.

    Science.gov (United States)

    Domene, X; Enders, A; Hanley, K; Lehmann, J

    2015-04-15

    Seven contrasting feedstocks were subjected to slow pyrolysis at low (300 or 350°C) and high temperature (550 or 600°C), and both biochars and the corresponding feedstocks tested for short-term ecotoxicity using basal soil respiration and collembolan reproduction tests. After a 28-d incubation, soil basal respiration was not inhibited but stimulated by additions of feedstocks and biochars. However, variation in soil respiration was dependent on both feedstock and pyrolysis temperature. In the last case, respiration decreased with pyrolysis temperature (r=-0.78; pbiochars. Inhibition effects were probably linked to high soluble Na and NH4 concentrations when both feedstocks and biochars were considered, but mostly to soluble Na when only biochars were taken into account. The general lack of toxicity of the set of slow pyrolysis biochars in this study at typical field application rates (?20 Mg ha(-1)) suggests a low short-term toxicity risk. At higher application rates (20-540 Mg ha(-1)), some biochars affected collembolan reproduction to some extent, but only strongly in the food waste biochars. Such negative impacts were not anticipated by the criteria set in currently available biochar quality standards, pointing out the need to consider ecotoxicological criteria either explicitly or implicitly in biochar characterization schemes or in management recommendations. PMID:25647370

  8. High-temperature pyrolysis mechanisms of coal model compounds

    Energy Technology Data Exchange (ETDEWEB)

    Penn, J.H.; Owens, W.H.

    1991-01-01

    The degradation of the carboxylic acid group has been examined with respect to potential pretreatment strategies for fossil fuel conversion processes. In one potential pretreatment strategy involving cation exchange of the carboxylic acid group, a series of benzoic acid and stearic acid salts have been chosen to model the tight'' carboxylic acids of immature fossil fuel feedstocks and have been pyrolyzed with an entrained flow reactor. Our preliminary results indicate that Group I and II salts yield primarily the parent acid. Benzoate salts also yield small amounts of benzene while the stearic acid salts give no other detectable products. In two alternative treatment strategies, esterification and anhydride preparation have also been accomplished with these compounds being subjected to the entrained flow reactor conditions. The benzoate esters give a number of products, such as benzaldehyde, benzene, and low MW gases. The formation of these compounds is extremely dependent on pyrolysis conditions and alkoxy chain length. A xenon flashlamp and an entrained flow reactor have been used to heat organic substrates to varying temperatures using different heating rates. Ultrarapid flashlamp pyrolysis (heating rate>10{sup 50}C/s) has been performed. Since the ultrarapid pyrolysis products differ from those observed with traditional heating techniques and differ from the products formed photochemically, the flashlamp pyrolysis products are attributed to high temperature thermal activation.

  9. Catalytic pyrolysis of palm kernel shell waste in a fluidized bed.

    Science.gov (United States)

    Kim, Sung Won; Koo, Bon Seok; Lee, Dong Hyun

    2014-09-01

    The catalytic pyrolysis of palm kernel shell was investigated in a fluidized bed with zsm-5 and equilibrium FCC (Ecat) catalysts. Catalytic pyrolysis oil yields were remarkably reduced and gas yields were increased due to the higher catalytic reaction of primary volatiles compared to non-catalytic pyrolysis. Char yields were affected by temperature and the pore structure of the catalysts. The pyrolysis oil was characterized by lower H/C and O/C molar ratios due to aromatization and deoxygenation of volatiles by the catalysts. The catalytic pyrolysis oils contained more oxygen and nitrogen and less sulfur than petroleum oils. The oils had a high concentration of nitriles, with a carbon number distribution similar to fatty acids. The catalytic pyrolysis oils featured high nitriles yield with Ecat and high aromatics yield in the light fraction with zsm-5, due to characteristics of the catalyst. The catalytic pyrolysis oils showed potentials as feedstocks for bio-diesel and chemicals. PMID:25006017

  10. Effects of pyrolysis temperature and heating time on biochar obtained from the pyrolysis of straw and lignosulfonate.

    Science.gov (United States)

    Zhang, Jie; Liu, Jia; Liu, Rongle

    2015-01-01

    In this study, the effects of pyrolysis temperature and heating time on the yield and physicochemical and morphological properties of biochar obtained from straw and lignosulfonate were investigated. As pyrolysis temperature increased, pH, ash content, carbon stability, and total content of carbon increased while biochar yield, volatile matter, total content of hydrogen, oxygen, nitrogen and sulfur decreased. The data from scanning electron microscope image and nuclear magnetic resonance spectra indicated an increase in porosity and aromaticity of biochar produced at a high temperature. The results showed that feedstock types could also influence characteristics of the biochar with absence of significant effect on properties of biochar for heating time. PMID:25435066

  11. Characterization of slow pyrolysis biochars: effects of feedstocks and pyrolysis temperature on biochar properties.

    Science.gov (United States)

    Kloss, Stefanie; Zehetner, Franz; Dellantonio, Alex; Hamid, Raad; Ottner, Franz; Liedtke, Volker; Schwanninger, Manfred; Gerzabek, Martin H; Soja, Gerhard

    2012-01-01

    Biochars are increasingly used as soil amendment and for C sequestration in soils. The influence of feedstock differences and pyrolysis temperature on biochar characteristics has been widely studied. However, there is a lack of knowledge about the formation of potentially toxic compounds that remain in the biochars after pyrolysis. We investigated biochars from three feedstocks (wheat straw, poplar wood, and spruce wood) that were slowly pyrolyzed at 400, 460, and 525°C for 5 h (straw) and 10 h (woodchips), respectively. We characterized the biochars' pH, electrical conductivity, elemental composition (by dry combustion and X-ray fluorescence), surface area (by N adsorption), water-extractable major elements, and cation exchange capacity (CEC). We further conducted differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffractometry to obtain information on the biochars' molecular characteristics and mineralogical composition. We investigated trace metal content, total polycyclic aromatic hydrocarbon (PAH) content, and PAH composition in the biochars. The highest salt (4.92 mS cm) and ash (12.7%) contents were found in straw-derived biochars. The H/C ratios of biochars with highest treatment temperature (HTT) 525°C were 0.46 to 0.40. Surface areas were low but increased (1.8-56 m g) with increasing HTT, whereas CEC decreased (162-52 mmol kg) with increasing HTT. The results of DSC and FTIR suggested a loss of labile, aliphatic compounds during pyrolysis and the formation of more recalcitrant, aromatic constituents. X-ray diffractometry patterns indicated a mineralogical restructuring of biochars with increasing HTT. Water-extractable major and trace elements varied considerably with feedstock composition, with trace elements also affected by HTT. Total PAH contents (sum of EPA 16 PAHs) were highly variable with values up to 33.7 mg kg; irrespective of feedstock type, the composition of PAHs showed increasing dominance of naphthalene with increasing HTT. The results demonstrate that biochars are highly heterogeneous materials that, depending on feedstock and HTT, may be suitable for soil application by contributing to the nutrient status and adding recalcitrant C to the soil but also potentially pose ecotoxicological challenges. PMID:22751041

  12. Pyrolysis and gasification of coal at high temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Zygourakis, K.

    1989-01-01

    Coals of different ranks will be pyrolyzed in a microscope hot-stage reactor using inert and reacting atmospheres. The macropore structure oft he produced chars will be characterized using video microscopy and digital image processing techniques to obtain pore size distributions. Comparative studies will quantify the effect of pyrolysis conditions (heating rates, final heat treatment temperatures, particle size and inert or reacting atmosphere) on the pore structure of the devolatilized chars. The devolatilized chars will be gasified in the regime of strong intraparticle diffusional limitations using O{sub 2}/N{sub 2} and O{sub 2}/H{sub 2}/N{sub 2} mixtures. Constant temperature and programmed-temperature experiments in a TGA will be used for these studies. Additional gasification experiments performed in the hot-stage reactor will be videotaped and selected images will be analyzed to obtain quantitative data on particle shrinkage and fragmentation.

  13. Formate-assisted pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    DeSisto, William Joseph; Wheeler, Marshall Clayton; van Heiningen, Adriaan R. P.

    2015-03-17

    The present invention provides, among other thing, methods for creating significantly deoxygenated bio-oils form biomass including the steps of providing a feedstock, associating the feedstock with an alkali formate to form a treated feedstock, dewatering the treated feedstock, heating the dewatered treated feedstock to form a vapor product, and condensing the vapor product to form a pyrolysis oil, wherein the pyrolysis oil contains less than 30% oxygen by weight.

  14. A granular-biomass high temperature pyrolysis model based on the Darcy flow

    Science.gov (United States)

    Guan, Jian; Qi, Guoli; Dong, Peng

    2015-03-01

    We established a model for the chemical reaction kinetics of biomass pyrolysis via the high-temperature thermal cracking of liquid products. We divided the condensable volatiles into two groups, based on the characteristics of the liquid prdoducts., tar and biomass oil. The effects of temperature, residence time, particle size, velocity, pressure, and other parameters on biomass pyrolysis and high-temperature tar cracking were investigated numerically, and the results were compared with experimental data. The simulation results showed a large endothermic pyrolysis reaction effect on temperature and the reaction process. The pyrolysis reaction zone had a constant temperature period in several layers near the center of large biomass particles. A purely physical heating process was observed before and after this period, according to the temperature index curve.

  15. Yield and Characteristics of Pyrolysis Products Obtained from Schizochytrium limacinum under Different Temperature Regimes

    OpenAIRE

    Renjie Dong; Benu Adhikari; Li Tian; Zonghu Ma; Ying Liu; Fang Ji; Yuguang Zhou; Gang Li

    2013-01-01

    Pyrolysis-gas chromatographic mass spectrometry (Py-GC/MS) was used to determine the yield and chemical composition of the pyrolysis products of Schizochytrium limacinum. The pyrolysis was carried out by varying the temperature from 300 °C to 800 °C. It was found that the main decomposition temperature of Schizochytrium limacinum was 428.16 °C, at which up to 66.5% of the mass was lost. A further 18.7% mass loss then occurred in a relatively slow pace until 760.2 °C due to complete decomposit...

  16. Microwave and Conventional Pyrolysis of Coffee Hulls at Different Temperatures for a Hydrogen Rich Gas

    OpenAIRE

    Menendez, Angel; Fernandez, Yolanda; Dominguez, Antonio; Pis, Juan; Valente Nabais, Joao; Carrott, Peter; Carrott, Manuela

    2006-01-01

    Microwave and Conventional Pyrolysis of Coffee Hulls at Different Temperatures for a Hydrogen Rich Gas. The paper reports the comparison of using a microwave and a conventional furnace to do the pysolysis of the coffee hulls.

  17. Formation characteristics of aerosol particles from pulverized coal pyrolysis in high-temperature environments.

    Science.gov (United States)

    Chen, Wei-Hsin; Du, Shan-Wen; Yang, Hsi-Hsien; Wu, Jheng-Syun

    2008-05-01

    The formation characteristics of aerosol particles from pulverized coal pyrolysis in high temperatures are studied experimentally. By conducting a drop-tube furnace, fuel pyrolysis processes in industrial furnaces are simulated in which three different reaction temperatures of 1000, 1200, and 1400 degrees C are considered. Experimental observations indicate that when the reaction temperature is 1000 degrees C, submicron particles are produced, whereas the particle size is dominated by nanoscale for the temperature of 1400 degrees C. Thermogravimetric analysis of the aerosol particles stemming from the pyrolysis temperature of 1000 degrees C reveals that the thermal behavior of the aerosol is characterized by a three-stage reaction with increasing heating temperature: (1) a volatile-reaction stage, (2) a weak-reaction stage, and (3) a soot-reaction stage. However, with the pyrolysis temperature of 1400 degrees C, the volatile- and weak-reaction stages almost merge together and evolve into a chemical-frozen stage. The submicron particles (i.e., 1000 degrees C) are mainly composed of volatiles, tar, and soot, with the main component of the nanoscale particles (i.e., 1400 degrees C) being soot. The polycyclic aromatic hydrocarbons (PAHs) contained in the aerosols are also analyzed. It is found that the PAH content in generated aerosols decreases dramatically as the pyrolysis temperature increases. PMID:18512447

  18. Catalytic pyrolysis of biomass: Effects of pyrolysis temperature, sweeping gas flow rate and MgO catalyst

    International Nuclear Information System (INIS)

    Cotton seed, as a biomass source, is pyrolysed in a tubular fixed-bed reactor under various sweeping gas (N2) flow rates at different pyrolysis temperatures. In the non-catalytic work, the maximum bio-oil yield was attained as 48.30% at 550 oC with a sweeping gas flow rate of 200 mL min-1. At the optimum conditions, catalytic pyrolysis of biomass samples was performed with various amounts of MgO catalyst (5, 10, 15, and 20 wt.% of raw material). Catalyst addition decreased the quantity of bio-oil yet increased the quality of bio-oil in terms of calorific value, hydrocarbon distribution and removal of oxygenated groups. It was observed that increasing the amount of catalyst used, decreased the oil yields while increased the gas and char yields. Bio-oils obtained at the optimum conditions were separated into aliphatic, aromatic and polar sub-fractions. After the application of column chromatography, bio-oils were subjected into elemental, FT-IR and 1H NMR analyses. Aliphatic sub-fractions of bio-oils were analyzed by GC-MS. It was deduced that the fuel obtained via catalytic pyrolysis mainly consisted of lower weight hydrocarbons in the diesel range. Finally, obtained results were compared with petroleum fractions and evaluated as a potential source for liquid fuels.

  19. Pyrolysis Oil from the Fruit and Cake of Jatropha curcas Produced Using a Low Temperature Conversion (LTC) Process: Analysis of a Pyrolysis Oil-Diesel Blend

    OpenAIRE

    Monique Kort-Kamp Figueiredo; Gilberto Alves Romeiro; Raquel Vieira Santana Silva; Priscila Alvares Pinto; Raimundo Nonato Damasceno; Luiz Antonio d`Avila; Amanda P. Franco

    2011-01-01

    Background: The LTC process is a technique that consists of heating solid residues at a temperature of 380oC - 420oC in an inert atmosphere and their products are evaluated individually: these products include pyrolysis oil, pyrolytic char, gas and water. The objective of this study was to compare the effects of the use of oils obtained by pyrolysis of Jatropha curcas as an additive for diesel in different proportions. Results: A Low Temperature C...

  20. Selective deoxygenation of aldehydes and alcohols on molybdenum carbide (Mo2C) surfaces

    Science.gov (United States)

    Xiong, Ke; Yu, Weiting; Chen, Jingguang G.

    2014-12-01

    The selective deoxygenation of aldehydes and alcohols without cleaving the Csbnd C bond is crucial for upgrading bio-oil and other biomass-derived molecules to useful fuels and chemicals. In this work, propanal, 1-propanol, furfural and furfuryl alcohol were selected as probe molecules to study the deoxygenation of aldehydes and alcohols on molybdenum carbide (Mo2C) prepared over a Mo(1 1 0) surface. The reaction pathways were investigated using temperature programmed desorption (TPD) and high resolution electron energy loss spectroscopy (HREELS). The deoxygenation of propanal and 1-propanol went through a similar intermediate (propoxide or ?2(C,O)-propanal) to produce propene. The deoxygenation of furfural and furfuryl alcohol produced a surface intermediate similar to adsorbed 2-methylfuran. The comparison of these results revealed the promising deoxygenation performance of Mo2C, as well as the effect of the furan ring on the selective deoxygenation of the Cdbnd O and Csbnd OH bonds.

  1. Fluctuations between conformational substrates in deoxygenated myoglobin

    International Nuclear Information System (INIS)

    Nuclear gamma resonace experiments on crystals of deoxygenated sperm whale myoglobin were performed at temperatures between 4.2 K and 300 K. Above 190 K the 2>-values start to increase very rapidly with temperature indicating fluctuation processes between conformational substates within the molecule. Large areas around the iron atom take part in these fluctuations. Below 200 K, the myoglobin molecules become frozen in various conformational substates. Above 200 K, fluctuations with a characteristic time of 10-7s are important. (orig.)

  2. A review of the toxicity of biomass pyrolysis liquids formed at low temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Diebold, J P [Thermalchemie, Inc., Lakewood, CO (United States)

    1997-04-01

    The scaleup of biomass fast pyrolysis systems to large pilot and commercial scales will expose an increasingly large number of personnel to potential health hazards, especially during the evaluation of the commercial use of the pyrolysis condensates. Although the concept of fast pyrolysis to optimize liquid products is relatively new, low-temperature pyrolysis processes have been used over the aeons to produce charcoal and liquid by-products, e.g., smoky food flavors, food preservatives, and aerosols containing narcotics, e.g., nicotine. There are a number of studies in the historical literature that concern the hazards of acute and long-term exposure to smoke and to the historical pyrolysis liquids formed at low temperatures. The reported toxicity of smoke, smoke food flavors, and fast pyrolysis oils is reviewed. The data found for these complex mixtures suggest that the toxicity may be less than that of the individual components. It is speculated that there may be chemical reactions that take place that serve to reduce the toxicity during aging. 81 refs.

  3. Effect of pyrolysis temperature on chemical and physical properties of sewage sludge biochar.

    Science.gov (United States)

    Khanmohammadi, Zahra; Afyuni, Majid; Mosaddeghi, Mohammad Reza

    2015-03-01

    The objective of this study was to evaluate the effects of pyrolysis temperatures (300, 400, 500, 600 and 700°C) on properties of biochar produced from an urban sewage sludge. Biochar yield significantly decreased from 72.5% at 300°C to 52.9% at 700°C, whereas an increase in temperature increased the gas yield. Biochar pH and electrical conductivity increased by 3.8 and 1.4 dS m?¹, proportionally to the increment of temperature. Biochar produced at low temperatures had higher total nitrogen and total organic carbon content but a lower C/N ratio, calcium carbonate equivalent, and total P, K and Na contents. Total and diethylene triamine penta acetic acid (DTPA)-extractable concentrations of Fe, Zn, Cu, Mn, Ni, Cr and Pb increased with increment of temperature. Lower DTPA-extractable concentrations of Fe, Zn, Cu, Mn, Ni and Pb were found in biochars compared to the sewage sludge. Pyrolysis decreased bulk density, whereas particle density and porosity increment was observed upon pyrolysis with increment of temperature. Sewage sludge saturated water content (?s ) was 130.4 g 100g?¹ and significantly greater than biochar, but biochar ?s significantly increased with temperature (95.7 versus 105.4 g 100g?¹ at 300 and 700°C, respectively). Pyrolysis decreased the biochar's water repellency, assessed by molarity of ethanol droplet (MED), compared to the sewage sludge. The lowest MED of 0.2 and water repellency rating of 3 were found for the biochar produced at 700°C. Based on our results and considering the energy consumption, pyrolysis temperature in the range of 300-400°C may be suggested for sewage sludge pyrolysis. PMID:25595292

  4. Preparation of indium sulfide thin film by nebulized spray pyrolysis technique at different substrate temperature

    International Nuclear Information System (INIS)

    Nebulized spray pyrolysis is a novel and easy technique of preparing thin films by which uniform precursor droplets can be deposited. Thin films having In2S3 compound were deposited with different substrate temperature by the above technique and they were characterized by X-Ray Diffraction (XRD) and optical absorption, transmission studies by UV-VIS spectrometer. The variation of thickness and electrical conductivity were also analyzed. The above properties were compared with the literature to find the effect of substrate temperature and due to this nebulized spray pyrolysis technique. (author)

  5. Effect of pyrolysis temperature on the composition of the oils obtained from sewage sludge

    International Nuclear Information System (INIS)

    Sewage sludge was pyrolysed in a quartz reactor at 350, 450, 550 and 950 oC. The pyrolysis oils from the sewage sludge were characterized in detail by means of gas chromatography-mass spectrometry (GC-MS). Changes in the composition of the oils related to the process conditions were assessed by normalizing the areas of the peaks. It was demonstrated that, as the temperature of pyrolysis increased from 350 to 950 oC, the concentration of mono-aromatic hydrocarbons in the oils also increased. Conversely, phenol and its alkyl derivatives showed a strong decrease in their concentration as temperature rose. Polycyclic aromatic hydrocarbons (PAHs) with two to three rings passed through a maximum at a pyrolysis temperature of 450 oC. PAHs with 4-5 rings also presented a major increase as temperature increased up to 450 oC, the concentration at 950 oC being slightly higher than that at 450 oC. Quantification of the main compounds showed that sewage sludge pyrolysis oils contain significant quantities of potentially high-value hydrocarbons such as mono-aromatic hydrocarbons and phenolic compounds. The oils also contain substantial concentrations of PAHs, even at the lowest temperature of 350 oC. The pathway to PAH formation is believed to be via the Diels-Alder reaction and also via secondary reactions of oxygenated compounds such as phenols.

  6. Effects of Feedstock and Pyrolysis Temperature on Biochar Adsorption of Ammonium and Nitrate

    Science.gov (United States)

    Gai, Xiapu; Wang, Hongyuan; Liu, Jian; Zhai, Limei; Liu, Shen; Ren, Tianzhi; Liu, Hongbin

    2014-01-01

    Biochar produced by pyrolysis of biomass can be used to counter nitrogen (N) pollution. The present study investigated the effects of feedstock and temperature on characteristics of biochars and their adsorption ability for ammonium N (NH4+-N) and nitrate N (NO3?-N). Twelve biochars were produced from wheat-straw (W-BC), corn-straw (C-BC) and peanut-shell (P-BC) at pyrolysis temperatures of 400, 500, 600 and 700°C. Biochar physical and chemical properties were determined and the biochars were used for N sorption experiments. The results showed that biochar yield and contents of N, hydrogen and oxygen decreased as pyrolysis temperature increased from 400°C to 700°C, whereas contents of ash, pH and carbon increased with greater pyrolysis temperature. All biochars could sorb substantial amounts of NH4+-N, and the sorption characteristics were well fitted to the Freundlich isotherm model. The ability of biochars to adsorb NH4+-N followed: C-BC>P-BC>W-BC, and the adsorption amount decreased with higher pyrolysis temperature. The ability of C-BC to sorb NH4+-N was the highest because it had the largest cation exchange capacity (CEC) among all biochars (e.g., C-BC400 with a CEC of 38.3 cmol kg?1 adsorbed 2.3 mg NH4+-N g?1 in solutions with 50 mg NH4+ L?1). Compared with NH4+-N, none of NO3?-N was adsorbed to biochars at different NO3? concentrations. Instead, some NO3?-N was even released from the biochar materials. We conclude that biochars can be used under conditions where NH4+-N (or NH3) pollution is a concern, but further research is needed in terms of applying biochars to reduce NO3?-N pollution. PMID:25469875

  7. Preparation of Organic/Inorganic Membrane by PDMS Low-temperature Pyrolysis

    Directory of Open Access Journals (Sweden)

    YU Jiao-Zhu, LI Lin, JIN Xin, DING Ling-Hua, WANG Tong-Hua

    2014-02-01

    Full Text Available The organic/inorganic membranes were prepared via low-temperature pyrolysis of polymers. Firstly, polymeric membranes were prepared by dip-coating method using PDMS as the precursor and stainless steel as the support. Then they were pyrolyzed at 350-480°C under inert atmosphere. The effects of preparation conditions on the gas separation performance of the organic/inorganic membranes were investigated. Chemical structure changes of PDMS in the pyrolysis process were studied by TG and FT-IR. The morphology of organic/inorganic membrane was characterized by SEM. The results showed that the organic/inorganic membranes with good gas separation performance could be successfully prepared by low-temperature pyrolysis of PDMS. The membrane retains part flexibility of PDMS, and presents good thermostability and high gas permselectivity. The gas separation performance and membrane layer structure of organic/inorganic membranes are greatly affected by the preparation conditions such as the PDMS concentration, coating times, pyrolysis temperature and properties of support. The gas separation performances prepared under the optimum condition are that the O2 permeation flux of 21.2 GPU(1 GPU=7.501×10-12m3(STP/(m2?s?Pa and O2/N2 selectivity of 2.28.

  8. Pyrolysis and gasification of coal at high temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Zygourakis, K.

    1992-02-10

    The macropore structure of chars is a major factor in determining their reactivity during the gasification stage. The major objectives of this contract were to (a) quantify by direct measurements the effect of pyrolysis conditions of the macropore structure, and (b) establish how the macropores affected the reactivity pattern, the ignition behavior and the fragmentation of the char particles during gasification in the regime of strong diffusional limitations. Results from this project provide much needed information on the factors that affect the quality of the solid products (chars) of coal utilization processes (for example, mild gasification processes). The reactivity data will also provide essential parameters for the optimal design of coal gasification processes. (VC)

  9. Influence of the Pyrolysis Temperature on Sewage Sludge Product Distribution, Bio-Oil, and Char Properties

    DEFF Research Database (Denmark)

    Trinh, Ngoc Trung; Jensen, Peter Arendt

    2013-01-01

    Fast pyrolysis may be used for sewage sludge treatment with the advantages of a significant reduction of solid waste volume and production of a bio-oil that can be used as fuel. A study of the influence of the reaction temperature on sewage sludge pyrolysis has been carried out using a pyrolysis centrifugel reactor (PCR) at 475, 525, 575, and 625 °C. Maxima of both organic oil yield of 41 wt % on a dry ash free feedstock basis (daf) and a sludge oil energy recovery of 50% were obtained at 575 °C. The water-insoluble fraction, molecular-weight distribution, higher heating value (HHV), and thermal behaviors of sludge oils were found to be considerably influenced by the applied pyrolysis temperatures. The sludge oil properties obtained at the optimal temperature of 575 °C were a HHV of 25.5 MJ/kg, a water-insoluble fraction of 18.7 wt %, a viscosity of 43.6 mPa s at 40 °C, a mean molecular weight of 392 g/mol, and metal concentrations lower than 0.14 wt % on a dry basis (db). Less optimal oil properties with respect to industrial applications were observed for oil samples obtained at 475 and 625 °C. Char properties of the 575 °C sample were an ash content of 81 wt % and a HHV of 6.1 MJ/kg db. A total of 95% of the sewage sludge phosphorus content was recovered in the char. The solid waste amount (char compared to sludge) was reduced to 52% on a bulk volume basis at the pyrolysis temperature of 575 °C.

  10. Effects of inherent alkali and alkaline earth metallic species on biomass pyrolysis at different temperatures.

    Science.gov (United States)

    Hu, Song; Jiang, Long; Wang, Yi; Su, Sheng; Sun, Lushi; Xu, Boyang; He, Limo; Xiang, Jun

    2015-09-01

    This work aimed to investigate effects of inherent alkali and alkaline earth metallic species (AAEMs) on biomass pyrolysis at different temperatures. The yield of CO, H2 and C2H4 was increased and that of CO2 was suppressed with increasing temperature. Increasing temperature could also promote depolymerization and aromatization reactions of active tars, forming heavier polycyclic aromatic hydrocarbons, leading to decrease of tar yields and species diversity. Diverse performance of inherent AAEMs at different temperatures significantly affected the distribution of pyrolysis products. The presence of inherent AAEMs promoted water-gas shift reaction, and enhanced the yield of H2 and CO2. Additionally, inherent AAEMs not only promoted breakage and decarboxylation/decarbonylation reaction of thermally labile hetero atoms of the tar but also enhanced thermal decomposing of heavier aromatics. Inherent AAEMs could also significantly enhance the decomposition of levoglucosan, and alkaline earth metals showed greater effect than alkali metals. PMID:26005925

  11. High-temperature pyrolysis mechanisms of coal model compounds. 1990 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Penn, J.H.; Owens, W.H.

    1991-01-01

    The degradation of the carboxylic acid group has been examined with respect to potential pretreatment strategies for fossil fuel conversion processes. In one potential pretreatment strategy involving cation exchange of the carboxylic acid group, a series of benzoic acid and stearic acid salts have been chosen to model the ``tight`` carboxylic acids of immature fossil fuel feedstocks and have been pyrolyzed with an entrained flow reactor. Our preliminary results indicate that Group I and II salts yield primarily the parent acid. Benzoate salts also yield small amounts of benzene while the stearic acid salts give no other detectable products. In two alternative treatment strategies, esterification and anhydride preparation have also been accomplished with these compounds being subjected to the entrained flow reactor conditions. The benzoate esters give a number of products, such as benzaldehyde, benzene, and low MW gases. The formation of these compounds is extremely dependent on pyrolysis conditions and alkoxy chain length. A xenon flashlamp and an entrained flow reactor have been used to heat organic substrates to varying temperatures using different heating rates. Ultrarapid flashlamp pyrolysis (heating rate>10{sup 50}C/s) has been performed. Since the ultrarapid pyrolysis products differ from those observed with traditional heating techniques and differ from the products formed photochemically, the flashlamp pyrolysis products are attributed to high temperature thermal activation.

  12. PYROLYSIS OF EMPTY FRUIT BUNCHES: INFLUENCE OF TEMPERATURE ON THE YIELDS AND COMPOSITION OF GASEOUS PRODUCT

    Directory of Open Access Journals (Sweden)

    Mohamad Azri Sukiran

    2014-01-01

    Full Text Available With the increasing concern on fossil fuel depletion and environmental problems, the utilization of renewable biomass resources is expected to play an important role in the future. Biomass can be converted into a variety of fuels and chemicals by different processes; one of which is pyrolysis that has been subjected to extensive research in recent years. In this study, pyrolysis of oil palm Empty Fruit Bunches (EFB was investigated using a quartz fluidised-fixed bed reactor. The effects of pyrolysis temperatures on the yields and composition of gaseous products were investigated. The temperatures of pyrolysis used were in the range of 300-600°C. The gaseous products from pyrolysis of (EFB were analyzed using a dual-channel micro-GC with Thermal Conductivity Detector (TCD. The highest and lowest gas yields obtained were 42.98 and 31.55% at 600 and 300°C, respectively. The gases detected were Carbon Monoxide (CO, carbon dioxide (CO2, Methane (CH4, Ethane (C2H6 and Ethylene (C2H4. At 300 and 400°C, the gas mixture comprised mainly CO2 (20% and CO (20%. Other gases such as CH4, C2H4 and C2H6 only evolved at higher temperature starting from 400°C with the yield of the latter two gases in very low concentration.

  13. Evaluating the effects of temperature on pressurized pyrolysis of Nannochloropsis oculata based on products yields and characteristics

    International Nuclear Information System (INIS)

    Highlights: • N. oculata is a suitable feedstock for pyrolysis due to high volatile matter. • Temperature effects on product yields and properties during pressurized pyrolysis. • Algal bio-oil has high energy content and has similar composition as diesel fuel. • Suitability of char as a fuel was based on Van Krevelen diagram. • Gas from pyrolysis of N. oculata has high percentage of combustible hydrocarbons. - Abstract: Biofuels derived from pyrolysis of microalgae can be potential alternatives for petroleum-derived fuels. Pyrolysis is an easily controllable thermochemical conversion process that yields energy fuels such as bio-oil, char and combustible gases. Microalgae is a very promising feedstock for this process since it has high lipid content, grows faster than lignocellulosic biomass, has high productivity and high photosynthetic efficiency. Several reaction parameters including temperature could affect the yield and quality of biofuels from pyrolysis. This paper aimed to evaluate the effect of temperature during pyrolysis of Nannochloropsis oculata using a pressurized fixed-bed batch-type reactor. Based on the results, the distribution of the products significantly varied with pyrolysis temperature, and the pyrolysis process can be manipulated to favor one of its products. Bio-oil with high heating value (HHV) of about 38 MJ/kg, due to its high carbon (76wt%) and hydrogen (11wt%) contents, and low oxygen content (7wt%), can be produced from N. oculata. It also consists mainly of saturated (34.95%) and unsaturated aliphatics (34.43%), and aromatics (14.19%) ranging from C8 to C21, which is comparable to diesel fuel. The HHV of the char (27 MJ/kg) and gas (27 MJ/m3) were also relatively high. Based on their heating values (HHV) and compositions, the char, bio-oil and gas produced from pyrolysis of N. oculata can be potentially used as alternative sources of energy. Mass and energy conversion efficiencies of the process were also estimated to be approximately equal to 76% and 68%, respectively

  14. Tar-free fuel gas production from high temperature pyrolysis of sewage sludge

    International Nuclear Information System (INIS)

    Highlights: • High temperature pyrolysis of sewage sludge was efficient for producing tar-free fuel gas. • Complete tar removal and volatile matter release were at elevated temperature of 1300 °C. • Sewage sludge was converted to residual solid with high ash content. • 72.60% of energy conversion efficiency for gas production in high temperature pyrolysis. • Investment and costing for tar cleaning were reduced. - Abstract: Pyrolysis of sewage sludge was studied in a free-fall reactor at 1000–1400 °C. The results showed that the volatile matter in the sludge could be completely released to gaseous product at 1300 °C. The high temperature was in favor of H2 and CO in the produced gas. However, the low heating value (LHV) of the gas decreased from 15.68 MJ/N m3 to 9.10 MJ/N m3 with temperature increasing from 1000 °C to 1400 °C. The obtained residual solid was characterized by high ash content. The energy balance indicated that the most heating value in the sludge was in the gaseous product

  15. Influence of temperature and particle size on the fixed bed pyrolysis of orange peel residues

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, L. [Departamento de Mecanica, Universidad de Pinar del Rio, Cuba. Calle Marti 270, final, Pinar del Rio (Cuba); Marquez-Montesinos, F. [Departamento de Quimica, Universidad de Pinar del Rio, Cuba. Calle Marti 270, final, Pinar del Rio (Cuba); Gonzalo, A.; Sanchez, J.L.; Arauzo, J. [Thermochemical Processes Group (GPT), Aragon Institute for Engineering Research (I3A), University of Zaragoza, Maria de Luna 3, 50018 Zaragoza (Spain)

    2008-09-15

    Orange peel is a residue from the production of juice. Its energetic valorisation could be interesting in areas where a different use, such as animal feed, is not possible. In order to investigate the viability of energy recovery, the pyrolysis of orange peel residues was studied in a fixed bed reactor, as an initial assessment of this process. The influence of pyrolysis temperature (300-600 C) and particle size (d{sub p}<300{mu}m and d{sub p}>800{mu}m) on product distribution, gas composition and char heating value has been investigated using a factorial design of experiments. Gas, char and water are the main products obtained; tar is only about 6 wt.% of the initial residue. Temperature was found to be the parameter which exerts a more important influence on the results than particle size. (author)

  16. Fuel and fuel blending components from biomass derived pyrolysis oil

    Science.gov (United States)

    McCall, Michael J.; Brandvold, Timothy A.; Elliott, Douglas C.

    2012-12-11

    A process for the conversion of biomass derived pyrolysis oil to liquid fuel components is presented. The process includes the production of diesel, aviation, and naphtha boiling point range fuels or fuel blending components by two-stage deoxygenation of the pyrolysis oil and separation of the products.

  17. Biomass Pyrolysis: Comments on Some Sources of Confusions in the Definitions of Temperatures and Heating Rates

    Directory of Open Access Journals (Sweden)

    Jacques Lédé

    2010-04-01

    Full Text Available Biomass pyrolysis is usually characterized on the basis of temperature and heating rate. Unfortunately, these parameters are badly defined in processing reactors as well as in laboratory devices. From the results of simplified models, the present paper points out the significant mistakes that can be made when assuming that the actual temperature and heating rate of reacting biomass particles are the same as those of the external heating medium. The difficulties in defining these two parameters are underlined in both cases of a heat source temperature supposed to be constant or to increase with time.

  18. Influence of Biomass Pyrolysis Temperature, Heating Rate and Type of Biomass on Produced Char in a Fluidized Bed Reactor

    OpenAIRE

    Toshiyuki Iwasaki; Seiichi Suzuki; Toshinori Kojima

    2014-01-01

    Biomass pyrolysis experiments were carried out in a fluidized bed reactor (FBR) and produced char yields were measured for 3 kinds of softwoods, 3 kinds of hardwoods, 2 kinds of herbaceous plants and 3 kinds of agricultural residues. Pyrolysis temperature range was between 300 °C and 1200 °C, and heating rate was fast (100–1000 °C/s) or slow (10 °C/min). After the pyrolysis, produced char was collected with bed particles and only the char was separated from bed particles by sieving. Surface o...

  19. Zinc Oxide Thin-Film Transistors Fabricated at Low Temperature by Chemical Spray Pyrolysis

    Science.gov (United States)

    Jeong, Yesul; Pearson, Christopher; Lee, Yong Uk; Winchester, Lee; Hwang, Jaeeun; Kim, Hongdoo; Do, Lee-Mi; Petty, Michael C.

    2014-11-01

    We report the electrical behavior of undoped zinc oxide thin-film transistors (TFTs) fabricated by low-temperature chemical spray pyrolysis. An aerosol system utilizing aerodynamic focusing was used to deposit the ZnO. Polycrystalline films were subsequently formed by annealing at the relatively low temperature of 140°C. The saturation mobility of the TFTs was 2 cm2/Vs, which is the highest reported for undoped ZnO TFTs manufactured below 150°C. The devices also had an on/off ratio of 104 and a threshold voltage of -3.5 V. These values were found to depend reversibly on measurement conditions.

  20. Influence of fast pyrolysis temperature on biochar labile fraction and short-term carbon loss in a loamy soil

    International Nuclear Information System (INIS)

    Production of bio-oil, gas and biochar from pyrolysis of biomass is considered a promising technology for combined production of bioenergy and recalcitrant carbon (C) suitable for sequestration in soil. Using a fast pyrolysis centrifuge reactor (PCR) the present study investigated the relation between fast pyrolysis of wheat straw at different reactor temperatures and the short-term degradability of biochar in soil. After 115 days incubation 3-12% of the added biochar-C had been emitted as CO2. On average, 90% of the total biochar-C loss occurred within the first 20 days of the experiment, emphasizing the importance of knowing the biochar labile fraction when evaluating a specific biochars C sequestration potential. The pyrolysis temperature influenced the outputs of biochar, bio-oil and syngas significantly, as well as the stability of the biochar produced. Contrary to slow pyrolysis a fast pyrolysis process may result in incomplete conversion of biomass due to limitations to heat transfer and kinetics. In our case chemical analysis of the biochars revealed unconverted cellulosic and hemicellulosic fractions, which in turn were found to be proportional with the short-term biochar degradation in soil. As these labile carbohydrates are rapidly mineralized, their presence lowers the biochar-C sequestration potential. By raising the pyrolysis temperature, biochar with none or low contents of these fractions can be produced, but this will be on the expense of the biochar quantity. The yield of CO2 neutral bio-oil is the other factor to optimize when adjusting the pyrolysis temperature settings to give the overall greatest climate change mitigation effect.

  1. Influence of fast pyrolysis temperature on biochar labile fraction and short-term carbon loss in a loamy soil

    DEFF Research Database (Denmark)

    Bruun, Esben; Hauggaard-Nielsen, Henrik

    2011-01-01

    Production of bio-oil, gas and biochar from pyrolysis of biomass is considered a promising technology for combined production of bioenergy and recalcitrant carbon (C) suitable for sequestration in soil. Using a fast pyrolysis centrifuge reactor (PCR) the present study investigated the relation between fast pyrolysis of wheat straw at different reactor temperatures and the short-term degradability of biochar in soil. After 115 days incubation 3–12% of the added biochar-C had been emitted as CO2. On average, 90% of the total biochar-C loss occurred within the first 20 days of the experiment, emphasizing the importance of knowing the biochar labile fraction when evaluating a specific biochars C sequestration potential. The pyrolysis temperature influenced the outputs of biochar, bio-oil and syngas significantly, as well as the stability of the biochar produced. Contrary to slow pyrolysis a fast pyrolysis process may result in incomplete conversion of biomass due to limitations to heat transfer and kinetics. In our case chemical analysis of the biochars revealed unconverted cellulosic and hemicellulosic fractions, which in turn were found to be proportional with the short-term biochar degradation in soil. As these labile carbohydrates are rapidly mineralized, their presence lowers the biochar-C sequestration potential. By raising the pyrolysis temperature, biochar with none or low contents of these fractions can be produced, but this will be on the expense of the biochar quantity. The yield of CO2 neutral bio-oil is the other factor to optimize when adjusting the pyrolysis temperature settings to give the overall greatest climate change mitigation effect.

  2. Influence of Biomass Pyrolysis Temperature, Heating Rate and Type of Biomass on Produced Char in a Fluidized Bed Reactor

    Directory of Open Access Journals (Sweden)

    Toshiyuki Iwasaki

    2014-05-01

    Full Text Available Biomass pyrolysis experiments were carried out in a fluidized bed reactor (FBR and produced char yields were measured for 3 kinds of softwoods, 3 kinds of hardwoods, 2 kinds of herbaceous plants and 3 kinds of agricultural residues. Pyrolysis temperature range was between 300 °C and 1200 °C, and heating rate was fast (100–1000 °C/s or slow (10 °C/min. After the pyrolysis, produced char was collected with bed particles and only the char was separated from bed particles by sieving. Surface of the produced char was observed by SEM to confirm bed particles adhesion behavior on the surface of char. Char-bed particles (alumina particles adhesion were observed mainly under fast pyrolysis condition for most of the biomass samples. Char yields by fast pyrolysis were much lower than those by slow pyrolysis of Eucalyptus camaldulensis (hardwood, Japanese cypress (softwood, Switchgrass (herbaceous plant and Bagasse (agricultural residue, respectively. In the case of fast pyrolysis condition, char yields from softwood species were lower than those from other biomass species.

  3. Effects of temperature and composite alumina on pyrolysis of sewage sludge.

    Science.gov (United States)

    Sun, Yu; Jin, Baosheng; Wu, Wei; Zuo, Wu; Zhang, Ya; Zhang, Yong; Huang, Yaji

    2015-04-01

    An interactive dual-circulating fluidized bed system has been proposed in which the pyrolysis of sewage sludge (SS) and incineration of biomass proceed simultaneously, and alumina is used as the bed material and heat carrier. The alumina coated with biomass ash would mix with sewage sludge in the pyrolysis reactor of this device. It is important to know the influence of composite alumina (CA) on the pyrolysis progress. Sewage sludge was pyrolyzed in a fixed bed reactor from 400 to 600°C using CA as catalyst. The effects of temperature and CA additive ratio on the products were investigated. The product yields and component distribution of non-condensable gas were more sensitive to the change of temperature, and the maximum liquid yield of 48.44wt.% and maximum Useable Energy of Liquid of 3871kJ/kg sludge were observed at 500°C with 1/5 CA/SS (mass ratio). The gas chromatography-mass spectrometry results showed that the increase of temperature enhanced devolatilization of organic matter and promoted cyclization and aromatization of aliphatics. The presence of CA could strengthen secondary cracking and interaction among primary products from different organic compounds, such as acid-amine condensation, and reduce the content of oxygenated compounds. When the CA additive amount exceeded a certain proportion, the aromatization was clearly strengthened. The effects of CA on decomposition of fatty acids and formation of aromatics were similar to that of temperature. This means that the reaction temperature could be lowered by introducing CA, which has a positive effect on reducing energy consumption. PMID:25872704

  4. Toluene pyrolysis studies and high temperature reactions of propargyl chloride

    Energy Technology Data Exchange (ETDEWEB)

    Kern, R.D.; Chen, H.; Qin, Z. [Univ. of New Orleans, LA (United States)

    1993-12-01

    The main focus of this program is to investigate the thermal decompositions of fuels that play an important role in the pre-particle soot formation process. It has been demonstrated that the condition of maximum soot yield is established when the reaction conditions of temperature and pressure are sufficient to establish a radical pool to support the production of polyaromatic hydrocarbon species and the subsequent formation of soot particles. However, elevated temperatures result in lower soot yields which are attributed to thermolyses of aromatic ring structures and result in the bell-shaped dependence of soot yield on temperature. The authors have selected several acyclic hydrocarbons to evaluate the chemical thermodynamic and kinetic effects attendant to benzene formation. To assess the thermal stability of the aromatic ring, the authors have studied the pyrolyses of benzene, toluene, ethylbenzene, chlorobenzene and pyridine. Time-of-flight mass spectrometry (TOF) is employed to analyze the reaction zone behind reflected shock waves. Reaction time histories of the reactants, products, and intermediates are constructed and mechanisms are formulated to model the experimental data. The TOF work is often performed with use of laser schlieren densitometry (LS) to measure density gradients resulting from the heats of various reactions involved in a particular pyrolytic system. The two techniques, TOF and LS, provide independent and complementary information about ring formation and ring rupture reactions.

  5. Pyrolysis at low-temperature of Mequinenza coal

    Energy Technology Data Exchange (ETDEWEB)

    Chorower, C.

    1940-01-01

    In the low-temperature distillation of Mequinenza coal 13 to 14.5% of tar was obtained in the carbonizing unit and 10.7 to 12.0% in the rotary drum with or without steam. The yield of semicoke was 65 to 70.5%; the gas production was 91 to 109 liter per kilogram. The tar was distilled with and without steam, the fractions were freed from phenol and paraffin and purified by treatment with H/sub 2/SO/sub 4/. The coal tested was in many respects more like mineral coal than soft coal (thus, the liquid tar was of higher specific gravity, was free from resins and lower in paraffin and higher in phenol than in the case of soft coal). The pitch content of the tar was very slight, the yield of viscous oils was high. By distillation with steam 32% of benzine was obtained. Of the high S content established in the coking 8.5% was present in the benzine, 6.3% in the motor oil and 5.6% in the lubricating oil from the tar.

  6. Epitaxial thick film of YBCO by high temperature spray pyrolysis for coated conductors

    International Nuclear Information System (INIS)

    YBCO thick films have been synthesized using a low cost spray pyrolysis method. We used an all nitrate precursor approach to grow epitaxial HTS oxide film on SrTiO3 (0 0 1) substrate at a high deposition rate and at high temperature (over 800 deg. C). In these experiments thick YBCO films (?m) were grown in situ at 850 deg. C within 4 min; the final sintering process is performed at the same temperature for 2 h under oxygen atmosphere before low temperature oxygen loading. X-ray diffraction results (?-2? scans and ? scans) show that the films have not only a strong c-axis texture (mis-orientation ?0.4 deg.) but also a sharp in-plane biaxial orientation (mis-orientation is ?1.4 deg.). The critical temperature (Tc) was 91 K and the critical current density (Jc) higher than 1.4x106 A/cm2 (at 77 K, 0 T), while film thickness is over 1 ?m. Spray pyrolysis is a promising technique for coated conductors

  7. Formation of PAH and soot during acetylene pyrolysis at different gas residence times and reaction temperatures

    International Nuclear Information System (INIS)

    The formation of polycyclic aromatic hydrocarbons (PAH) and soot from the pyrolysis of acetylene was studied, taking into account the influence of the operating conditions, such as gas residence time and temperature. The influence of gas residence time was considered between 1.28 and 3.88 s for the experiments carried out under different temperatures from 1073 to 1223 K. The total PAH was calculated as the addition of PAH concentration found in different locations, namely adsorbed on soot and on the reactor walls, and at the outlet gas stream. The relationship between the PAH concentrations and their carcinogenic equivalence sum (KE) was also evaluated. The results obtained showed that temperature and residence time have a high influence on pyrolysis products, especially on the PAH concentration adsorbed on soot, which exhibited the highest KE in all cases studied. -- Highlights: ? This study analyses the influence of gas residence time and reaction temperature on PAH and soot formation. ? The present work develops an analytical method for PAH-priorities quantification. ? A major amount of PAH adsorbed on soot is found under every evaluated condition. ? High PAH concentration does not necessarily involve more dangerous effects.

  8. Nitrogen enrichment potential of biochar in relation to pyrolysis temperature and feedstock quality.

    Science.gov (United States)

    Jassal, Rachhpal S; Johnson, Mark S; Molodovskaya, Marina; Black, T Andrew; Jollymore, Ashlee; Sveinson, Kelly

    2015-04-01

    Nitrogen (N) enrichment of biochar from both inorganic and organic waste N sources has the potential to add economic and environmental value through its use as a slow release N fertilizer. We investigated the sorption of N by, and its release from, biochar made at pyrolysis temperatures of 400, 500 and 600 °C from three feedstocks: poultry litter (PL with a carbon (C) to N ratio (C:N) of 14), softwood chips of spruce-pine-fir (SPF with a C:N of 470), and a 50:50 mixture of PL and SPF (PL/SPF). The prepared biochars were enriched with ammonium nitrate (AN) and urea ammonium nitrate (UAN). PL biochars had the lowest C content (50-56% C), but the highest pH (9.3-9.9), electrical conductivity (EC, 780-960 dS m(-1)), cation exchange capacity (CEC, 40-46 cmol kg(-1)), and N content (3.3-4.5%). While N content and hydrogen (H) to C atomic ratio (H:C) decreased with increasing pyrolysis temperature irrespective of the feedstock used, both pH and EC slightly increased with pyrolysis temperature for all feedstocks. The PL and SPF biochars showed similar H:C and also similar N sorption and N release at all pyrolysis temperatures. These biochars sorbed up to 5% N by mass, irrespective of the source of N. However, PL/SPF biochar performed poorly in sorbing N from either AN or UAN. Biochar H:C was found to be unrelated to N sorption rates, suggesting that physical adsorption on active surfaces was the main mechanism of N sorption in these biochars. There were minor differences between N sorbed from NO3-N and NH4-N among different biochars. Very small amounts of sorbed N (0.2-0.4 mg N g(-1) biochar) was released when extracted with 1 M KCl solution, indicating that the retained N was strongly held in complex bonds, more so for NH4-N because the release of NO3-N was 3-4 times greater than that of NH4-N. NH4-N sorption far exceeded the effective CEC of the biochars, thereby suggesting that most of the sorption may be due to physical entrapment of NH4(+) in biochar pores. The results of this study suggest that biochar can be used to remove excess N from poultry and dairy manure and be a good mitigation option for reducing N leaching and gaseous losses. PMID:25621388

  9. Characterization of bio-oil and biochar from high-temperature pyrolysis of sewage sludge.

    Science.gov (United States)

    Chen, Hongmei; Zhai, Yunbo; Xu, Bibo; Xiang, Bobin; Zhu, Lu; Qiu, Lei; Liu, Xiaoting; Li, Caiting; Zeng, Guangming

    2015-02-01

    The influence of temperature (550-850°C) on the characteristics of bio-oil and biochar from the pyrolysis of sewage sludge (SS) in a horizontal tube reactor was investigated. Results showed that when the pyrolysis temperature increased from 550°C to 850°C, the yield of bio-oil decreased from 26.16% (dry ash-free basis) to 20.78% (dry ash-free basis). Main components of bio-oil were phenols, esters, cholests, ketones, amides, indoles, and nitriles. Besides, the elevated heating rate of 25°C/min was demonstrated to favour the complete combustion of bio-oil. Moreover, caused by the increase in temperature, the yield of biochar decreased from 54.9 to 50.6wt%, Brunauer-Emmet-Teller surface area increased from 48.51 to 81.28?m(2)/g. Furthermore, pH was increased from 5.93 of SS to 7.15-8.96 of biochar. The negative ?-potential was also strengthened (-13.87 to -11.30?mV) and principal functional groups on the surface of biochar were -OH, C=O, C=C, -NO2, and S=O. PMID:25518986

  10. Flame temperature trends in reacting vanadium and tungsten ethoxide fluid sprays during CO2-laser pyrolysis

    Science.gov (United States)

    Mwakikunga, B. W.; Mudau, A. E.; Brink, N.; Willers, C. J.

    2011-11-01

    We observe the "invisible-to-the-naked-eye" flames of tungsten and vanadium ethoxide aerosols when ignited at moderate laser excitation (0flames measured using FTIR-spectrometer were used to calculate the pyrolysis flame temperature at various laser intensities and wavelengths. New energy balance equations have been derived—the transient temperature one extended from Haggerty-Cannon equation and the other based on standard resonance analysis. Fitting these models to experimental data reveals that only small amounts (1.33% and 4.32%, respectively) of the laser power are used in the pyrolysis of the precursor ethoxide aerosols into the desired oxide nanostructures. The low levels of specific heat capacity values obtained in these sprays suggest that these are electronic heat capacities rather than lattice heat capacities; enthalpies are also obtained. The experimental temperature-laser power trends observed were in agreement with previous findings from Tenegal et al. (Chem. Phys. Lett. 335:155, 2001). The damping coefficients, and hence the saturation intensities confirm that the vanadium containing precursor liquid is harder to dissociate into final products than the tungsten precursor as observed experimentally.

  11. Temperature dependence of Fluorine-doped tin oxide films produced by ultrasonic spray pyrolysis

    International Nuclear Information System (INIS)

    Fluorine-doped tin oxide (FTO) films were prepared at different substrate temperatures by ultrasonic spray pyrolysis technique on glass substrates. Among F-doped tin oxide films, the lowest resistivitiy was found to be 6.2 x 10-4 ?-cm for a doping percentage of 50 mol% of fluorine in 0.5 M solution, deposited at 400 oC. Hall coefficient analyses and secondary ion mass spectrometry (SIMS) measured the electron carrier concentration that varies from 3.52 x 1020 cm-3 to 6.21 x 1020 cm-3 with increasing fluorine content from 4.6 x 1020 cm-3 to 7.2 x 1020 cm-3 in FTO films deposited on various temperatures. Deposition temperature on FTO films has been optimized for achieving a minimum resistivity and maximum optical transmittance.

  12. Factors affecting sorption of nitro explosives to biochar: pyrolysis temperature, surface treatment, competition, and dissolved metals.

    Science.gov (United States)

    Oh, Seok-Young; Seo, Yong-Deuk

    2015-05-01

    The application of rice straw-derived biochar for removing nitro explosives, including 2,4-dinitrotoluene (DNT), 2,4,6-trinitrotoluene (TNT), and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), from contaminated water was investigated through batch experiments. An increase in the pyrolysis temperature from 250 to 900°C in general led to higher pH, surface area, cation exchange capacity (CEC), point of zero charge, and C:O ratio of biochar. The maximum sorption capacity estimated by a mixed sorption-partition model increased when pyrolysis temperatures were elevated from 250 to 900°C, indicating that C content and aromaticity of biochar were strongly related to the sorption of nitro explosives to biochar. Surface treatment with acid or oxidant increased the sorption capacity of biochar for the two strong ?-acceptor compounds (DNT and TNT) but not for RDX. However, the enhancement of sorption capacity was not directly related to increased surface area and CEC. Compared with single-sorption systems, coexistence of explosives or cationic metals resulted in decreased sorption of each explosive to biochar, suggesting that sorption of nitro explosives and cationic metals to electron-rich portions in biochar was competitive. Our results suggest that ?-? electron donor acceptor interactions are main sorption mechanisms and that changing various conditions can enhance or reduce the sorption of nitro explosives to biochar. PMID:26024263

  13. Influence of inherent minerals and pyrolysis temperature on the yield of pyrolysates of some Pakistani coals

    International Nuclear Information System (INIS)

    An analytical method has been developed to quantitize tar, liquids and gaseous products resulting from the flash pyrolysis of sub-bituminous Makarwal coal. The method involves the thermal decomposition of 200 mg of 85-mesh size coal at 690 deg. C under the flow of nitrogen using Shimadzu PYR-2A open tubular pyrolyzer. The resulting tar and liquid fractions were separated using two traps at the exit of the pyrolyzer while the gaseous products leaving the traps were on line injected to gas chromatograph equipped with porapak Q column and flame ionization detector for the analysis. Effect of demineralization on the yields of products was investigated by treating raw samples with 2 M HCl. Removal of inherent minerals from coal by acid wash decreased the yield of total volatiles indicating catalytic properties of mineral under the condition used in present study. The influence of pyrolysis temperature on the yield of pyrolysates and hydrocarbon gases, resulting from raw coal samples, was studied over the temperature range of 500-770 deg. C.

  14. Structures and lithium storage performance of Si-O-C composite materials depending on pyrolysis temperatures

    Science.gov (United States)

    Fukui, Hiroshi; Eguchi, Katsuya; Ohsuka, Hisashi; Hino, Takakazu; Kanamura, Kiyoshi

    2013-12-01

    A polymer blend of a partially-branched phenyl-substituted polysilane, (Ph2Si)0.85(PhSi)0.15, and polystyrene (1:1 by weight) has been prepared to produce silicon oxycarbide (Si-O-C) composite materials through pyrolysis in the temperature range 700-1200 °C under an argon atmosphere. According to elemental analysis results, carbon is a major constituent in a series of Si-O-C composite materials obtained in this study. Completely amorphous features were observed for the composite materials obtained between 700 and 1100 °C, while a clearly discernible crystalline evolution of silicon carbide (SiC) phases was found in a glass network of the composite material obtained at 1200 °C. This paper also deals with electrochemical lithiation and delithiation for the series of Si-O-C composite materials. The first delithiation capacities of these composite materials were highly dependent on pyrolysis temperatures. The composite material obtained at 700 °C had the maximum delithiation capacity of ca. 800 mA h g-1, while the composite material obtained at 1200 °C showed the minimum delithiation capacity of ca. 330 mA h g-1. The crystalline evolution of SiC phases is thought to cause such a drastic decrease in delithiation capacity at 1200 °C.

  15. Influence of inherent minerals and pyrolysis temperature on the yield of pyrolysates of some Pakistani coals

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Tauqeer; Awan, Iftikhar A.; Nisar, Jan [National Center of Excellence in Physical Chemistry, University of Peshawar, Peshawar 25120 (Pakistan); Ahmad, Imtiaz [Institute of Chemical Sciences, University of Peshawar, Peshawar (Pakistan)

    2009-05-15

    An analytical method has been developed to quantize tar, liquids and gaseous products resulting from the flash pyrolysis of sub-bituminous Makarwal coal. The method involves the thermal decomposition of 200 mg of 85-mesh size coal at 690 C under the flow of nitrogen using Shimadzu PYR-2A open tubular pyrolyzer. The resulting tar and liquid fractions were separated using two traps at the exit of the pyrolyzer while the gaseous products leaving the traps were on line injected to gas chromatograph equipped with porapak Q column and flame ionization detector for the analysis. Effect of demineralization on the yields of products was investigated by treating raw samples with 2 M HCl. Removal of inherent minerals from coal by acid wash decreased the yield of total volatiles indicating catalytic properties of mineral under the condition used in present study. The influence of pyrolysis temperature on the yield of pyrolysates and hydrocarbon gases, resulting from raw coal samples, was studied over the temperature range of 500-770 C. (author)

  16. Formation of brominated pollutants during the pyrolysis and combustion of tetrabromobisphenol A at different temperatures

    International Nuclear Information System (INIS)

    Tetrabromobisphenol A (TBBPA) is the most widely used brominated flame retardant worldwide. A detailed examination of the degradation products emitted during thermal decomposition of TBBPA is presented in the study. Runs were performed in a laboratory furnace at different temperatures (650 and 800 °C) and in different atmospheres (nitrogen and air). More than one hundred semivolatile compounds have been identified by GC/MS, with special interest in brominated ones. Presence of HBr and brominated light hydrocarbons increased with temperature and in the presence of oxygen. Maximum formation of PAHs is observed at pyrolytic condition at the higher temperature. High levels of 2,4-, 2,6- and 2,4,6- bromophenols were found. The levels of polybrominated dibenzo-p-dioxins and furans have been detected in the ppm range. The most abundant isomers are 2,4,6,8-TeBDF in pyrolysis and 1,2,3,7,8-PeBDF in combustion. These results should be considered in the assessment of thermal treatment of materials containing brominated flame retardants. - Highlights: • Decomposition of a brominated flame retardant is performed in a laboratory furnace. • Both pyrolysis and combustion at two different temperatures are studied. • Brominated organic compounds such as Br-dioxins and furans are analysed. • Main product of decomposition is HBr, accounting for ca. 50%. • Very high and dangerous levels of PBDD/Fs and precursors (bromophenols) are detected. - TBBPA mainly decomposes to give HBr and brominated hydrocarbons at high temperature, but high levels of bromophenols and polybrominated dibenzo-p-dioxins and furans are also produced

  17. High temperature pyrolysis: A new system for isotopic and elemental analysis

    International Nuclear Information System (INIS)

    A new method for the automated sample conversion and on-line determination of deuterium, carbon, nitrogen and oxygen isotopes for organic and inorganic substances is presented. The samples are pyrolytically decomposed in presence of reactive carbon in a high temperature pyrolysis system (HTP) at a temperature higher than 1400 deg. C. The method has a great potential for the analysis of hydrogen, carbon, nitrogen and oxygen stable isotopes ratios. The instrumentation and application is very simple and cost effective. The reproducibility of the ?-values is 3 per mille for D/H, 0.3 per mille for 18O, and 0.2 per mille for 13C and 15N respectively. The system is suitable for solid, liquid and gaseous samples. Results are presented for the isotopic composition of international reference materials which show the precision and accuracy of the method. (author)

  18. RELATION BETWEEN MECHANICAL PROPERTIES AND PYROLYSIS TEMPERATURE OF PHENOL FORMALDEHYDE RESIN FOR GAS SEPARATION MEMBRANES

    Directory of Open Access Journals (Sweden)

    MONIKA ŠUPOVÁ

    2012-03-01

    Full Text Available The aim of this paper has been to characterize the relation between the pyrolysis temperature of phenol-formaldehyde resin, the development of a porous structure, and the mechanical properties for the application of semipermeable membranes for gas separation. No previous study has dealt with this problem in its entirety. Phenol-formaldehyde resin showed an increasing trend toward micropore porosity in the temperature range from 500 till 1000°C, together with closure of mesopores and macropores. Samples cured and pyrolyzed at 1000°C pronounced hysteresis of desorption branch. The ultimate bending strength was measured using a four-point arrangement that is more suitable for measuring of brittle materials. The chevron notch technique was used for determination the fracture toughness. The results for mechanical properties indicated that phenol-formaldehyde resin pyrolyzates behaved similarly to ceramic materials. The data obtained for the material can be used for calculating the technical design of gas separation membranes.

  19. Low temperature pyrolysis of coal or oil shale in the presence of calcium compounds

    Science.gov (United States)

    Khan, M. Rashid (Morgantown, WV)

    1988-01-01

    A coal pyrolysis technique or process is described in which particulate coal is pyrolyzed in the presence of about 5 to 21 wt. % of a calcium compound selected from calcium oxide, calcined (hydrate) dolomite, or calcined calcium hydrate to produce a high quality hydrocarbon liquid and a combustible product gas which are characterized by low sulfur content. The pyrolysis is achieved by heating the coal-calcium compound mixture at a relatively slow rate at a temperature of about 450.degree. to 700.degree. C. over a duration of about 10 to 60 minutes in a fixed or moving bed reactor. The gas exhibits an increased yield in hydrogen and C.sub.1 -C.sub.8 hydrocarbons and a reduction in H.sub.2 S over gas obtainable by pyrolyzing cola without the calcium compound. The liquid product obtained is of a sufficient quality to permit its use directly as a fuel and has a reduced sulfur and oxygen content which inhibits polymerization during storage.

  20. Indium oxide thin-film transistors processed at low temperature via ultrasonic spray pyrolysis.

    Science.gov (United States)

    Faber, Hendrik; Lin, Yen-Hung; Thomas, Stuart R; Zhao, Kui; Pliatsikas, Nikos; McLachlan, Martyn A; Amassian, Aram; Patsalas, Panos A; Anthopoulos, Thomas D

    2015-01-14

    The use of ultrasonic spray pyrolysis is demonstrated for the growth of polycrystalline, highly uniform indium oxide films at temperatures in the range of 200-300 °C in air using an aqueous In(NO3)3 precursor solution. Electrical characterization of as-deposited films by field-effect measurements reveals a strong dependence of the electron mobility on deposition temperature. Transistors fabricated at ?250 °C exhibit optimum performance with maximum electron mobility values in the range of 15-20 cm(2) V (-1) s(-1) and current on/off ratio in excess of 10(6). Structural and compositional analysis of as-grown films by means of X-ray diffraction, diffuse scattering, and X-ray photoelectron spectroscopy reveal that layers deposited at 250 °C are denser and contain a reduced amount of hydroxyl groups as compared to films grown at either lower or higher temperatures. Microstructural analysis of semiconducting films deposited at 250 °C by high resolution cross-sectional transmission electron microscopy reveals that as-grown layers are extremely thin (?7 nm) and composed of laterally large (30-60 nm) highly crystalline In2O3 domains. These unique characteristics of the In2O3 films are believed to be responsible for the high electron mobilities obtained from transistors fabricated at 250 °C. Our work demonstrates the ability to grow high quality low-dimensional In2O3 films and devices via ultrasonic spray pyrolysis over large area substrates while at the same time it provides guidelines for further material and device improvements. PMID:25490965

  1. Influence of pyrolysis temperature on biochar property and function as a heavy metal sorbent in soil.

    Science.gov (United States)

    Uchimiya, Minori; Wartelle, Lynda H; Klasson, K Thomas; Fortier, Chanel A; Lima, Isabel M

    2011-03-23

    While a large-scale soil amendment of biochars continues to receive interest for enhancing crop yields and to remediate contaminated sites, systematic study is lacking in how biochar properties translate into purported functions such as heavy metal sequestration. In this study, cottonseed hulls were pyrolyzed at five temperatures (200, 350, 500, 650, and 800 °C) and characterized for the yield, moisture, ash, volatile matter, and fixed carbon contents, elemental composition (CHNSO), BET surface area, pH, pHpzc, and by ATR-FTIR. The characterization results were compared with the literature values for additional source materials: grass, wood, pine needle, and broiler litter-derived biochars with and without post-treatments. At respective pyrolysis temperatures, cottonseed hull chars had ash content in between grass and wood chars, and significantly lower BET surface area in comparison to other plant source materials considered. The N:C ratio reached a maximum between 300 and 400 °C for all biomass sources considered, while the following trend in N:C ratio was maintained at each pyrolysis temperature: wood?cottonseed hull?grass?pine needle?broiler litter. To examine how biochar properties translate into its function as a heavy metal (NiII, CuII, PbII, and CdII) sorbent, a soil amendment study was conducted for acidic sandy loam Norfolk soil previously shown to have low heavy metal retention capacity. The results suggest that the properties attributable to the surface functional groups of biochars (volatile matter and oxygen contents and pHpzc) control the heavy metal sequestration ability in Norfolk soil, and biochar selection for soil amendment must be made case-by-case based on the biochar characteristics, soil property, and the target function. PMID:21348519

  2. Fluidised bed catalytic pyrolysis of scrap tyres: influence of catalyst:tyre ratio and catalyst temperature.

    Science.gov (United States)

    Williams, Paul T; Brindle, Alexander J

    2002-12-01

    Pyrolysis with on-line Zeolite catalysis of scrap tyres was undertaken in a fluidised bed reactor with the aim of maximising the production of higher value single ring aromatic hydrocarbons in the derived oil. Experiments were carried out in relation to the ratio of the catalyst to tyre feedstock and the temperature of the catalyst bed. Two Zeolite catalysts were examined, a Y-type Zeolite catalyst and Zeolite ZSM-5 catalyst of differing pore size and surface activity. The composition of the oils derived from the uncatalysed fluidised bed pyrolysis of tyres showed that benzene concentration was 0.2 wt%, toluene concentration was 0.8 wt%, o-xylene was 0.3 wt%, m/p-xylenes were 1.8 wt% and limonene was 4.3 wt%. Benzene, toluene and xylenes present in the oils showed a significant increase in the presence of both of the catalysts. The maximum concentrations of these chemicals for the Y-Zeolite (CBV-400) catalyst was 1 wt% for benzene, 8wt% for toluene, 3 wt% for o-xylene and 8.5 wt% for m/p-xylenes, produced at a catalyst:tyre ratio of 1.5. There was less influence of catalyst temperature on the yield of benzene, toluene and xylenes, however, increasing the temperature of the catalyst resulted in a marked decrease in limonene concentration. The Y-type Zeolite catalyst produced significantly higher concentrations of benzene, toluene and xylenes which was attributed to the larger pore size and higher surface acidity of the Y-Zeolite catalyst compared to the Zeolite ZSM-5 catalyst. PMID:12549667

  3. Flash pyrolysis at high temperature of ligno-cellulosic biomass and its components - production of synthesis gas

    International Nuclear Information System (INIS)

    Pyrolysis is the first stage of any thermal treatment of biomass and governs the formation of synthesis gas for the production of electricity, hydrogen or liquid fuels. The objective of this work is to establish a link between the composition of a biomass and its pyrolysis gas. We study experimental flash pyrolysis and fix the conditions in which quantities of gas are maximal, while aiming at a regime without heat and mass transfer limitations (particles about 100 ?m): temperature of 950 C and residence time of about 2 s. Then we try to predict gas yields of any biomass according to its composition, applicable in this situation where thermodynamic equilibrium is not reached. We show that an additivity law does not allow correlating gas yields of a biomass with fractions of cellulose, hemi-cellulose and lignin contained in this biomass. Several explanations are suggested and examined: difference of pyrolytic behaviour of the same compound according to the biomass from which it is extracted, interactions between compounds and influence of mineral matter. With the aim of industrial application, we study pyrolysis of millimetric and centimetric size particles, and make a numerical simulation of the reactions of pyrolysis gases reforming. This simulation shows that the choice of biomass affects the quantities of synthesis gas obtained. (author)

  4. The low-temperature pyrolysis of combustible plutonium-contaminated materials (PCM)

    International Nuclear Information System (INIS)

    The process of incineration of combustible PCM yields an excellent waste volume reduction, producing an inorganic residue which is both stable for interim storage and is a convenient starting material for any subsequent immobilization process. The ash is physically very suitable for any extraction of plutonium which may be required. However, conventional incinerator temperatures pose materials of construction problems and, in addition, there is evidence that plutonium extraction becomes progressively more difficult as the temperature exceeds the 600-7000C range. Low-temperature pyrolysis seeks to retain the benefits of incineration whilst, by limiting the operating temperature, controlling the problems of corrosion and plutonium extraction. The process involves the low-temperature (500-7000C) treatment of the waste in an inert atmosphere to produce a carbonaceous char, followed by a second, air-oxidation stage, again at low temperature. Primary off-gas treatment by after-burning is envisaged. The results of bench-scale and small-scale pilot plant work to examine these conditions are reported. (author)

  5. De-oxygenation of CO2 by using Hydrogen, Carbon and Methane over Alumina-Supported Catalysts

    OpenAIRE

    Raskar, R. Y.; Kale, K. B.; Gaikwad, A. G.

    2012-01-01

    The de-oxygenation of CO2 was explored by using hydrogen, methane, carbon etc., over alumina supported catalysts. The alumina-supported ruthenium, rhodium, platinum, molybdenum, vanadium and magnesium catalysts were first reduced in hydrogen atmosphere and then used for the de-oxygenation of CO2. Furthermore, experimental variables for the de-oxygenation of CO2 were temperature (range 50 to 650 oC), H2/CO2 mole ratios (1.0 to 5), and catalyst loading (0.5 to 10 wt %). During the de-oxygenatio...

  6. Low oxygen biomass-derived pyrolysis oils and methods for producing the same

    Science.gov (United States)

    Marinangeli, Richard; Brandvold, Timothy A; Kocal, Joseph A

    2013-08-27

    Low oxygen biomass-derived pyrolysis oils and methods for producing them from carbonaceous biomass feedstock are provided. The carbonaceous biomass feedstock is pyrolyzed in the presence of a catalyst comprising base metal-based catalysts, noble metal-based catalysts, treated zeolitic catalysts, or combinations thereof to produce pyrolysis gases. During pyrolysis, the catalyst catalyzes a deoxygenation reaction whereby at least a portion of the oxygenated hydrocarbons in the pyrolysis gases are converted into hydrocarbons. The oxygen is removed as carbon oxides and water. A condensable portion (the vapors) of the pyrolysis gases is condensed to low oxygen biomass-derived pyrolysis oil.

  7. Evaluation of Integrated Time-Temperature Effect in Pyrolysis Process of Historically Contaminated Soils with Cadmium (Cd and Lead (Pb

    Directory of Open Access Journals (Sweden)

    Bulm?u C

    2013-04-01

    Full Text Available It is already known that heavy metals pollution causes important concern to human and ecosystem health. Heavy metals in soils at the European level represents 37.3% between main contaminates affecting soils (EEA, 2007. This paper illustrates results obtained in the framework of laboratory experiments concerning the evaluation of integrated time-temperature effect in pyrolysis process applied to contaminated soil by two different ways: it is about heavy metals historically contaminated soil from one of the most polluted areas within Romania, and artificially contaminated with PCB-containing transformer oil. In particular, the authors focused on a recent evaluation of pyrolysis efficiency on removing lead (Pb and cadmium (Cd from the contaminated soil. The experimental study evaluated two important parameters related to the studied remediation methodology: thermal process temperature and the retention time in reactor of the contaminated soils. The remediation treatments were performed in a rotary kiln reactor, taking into account three process temperatures (400°C, 600°C and 800°C and two retention times: 30 min. and 60 min. Completed analyses have focused on pyrolysis solids and gas products. Consequently, both ash and gas obtained after pyrolysis process were subjected to chemical analyses.

  8. Effect of biochar produced at different pyrolysis temperature on the soil respiration of abandoned mine soil

    Science.gov (United States)

    Kim, Yong Seong; Kim, Juhee; Hwang, Wonjae; Hyun, Seunghun

    2015-04-01

    Contaminated soils near an abandoned mine site included the high acidic mine tailing have received great interest due to potential risk to human health, because leachable elements in low pH continuously release from mine site soil with ground water and precipitation event. Biochar, which is the obtained pyrolysis process of biomass, is used as a soil amendments and carbon storage. Especially, many researchers report that the biochar application to soil show increasing soil pH, CEC, adsorption capacity of various elements, as well as, enhanced microbial activity. Therefore, biochar application to contaminated soil near abandoned mine site is expected to have a positive effects on management of these site and soils through the decreased leachability of contaminants. However, effects of biochar application to these site on the soil respiration, as a common measure of soil health, are poorly understood. The objective of this study is to evaluate the effects of biochar application to abandoned mine site soil on the microbial activity with soil respiration test. Biochar was obtained from giant Miscanthus in a slow pyrolysis process (heating rate of 10° C min-1 and N2 gas flow rate of 1.2 L min-1) at the temperature of 400° C (BC4) and 700° C (BC7), respectively. All biochar samples were prepared with grinding and sieving for particle size control (150~500?m). Soil sample was collected from abandoned mine site at Korea (36° 58'N, 128° 10'E). Main contaminants of this soil were As (12.5 g kg-1), Pb (7.3 g kg-1), and Zn (1.1 g kg-1). Biochars were applied (5% by dry weight) to the soil (final mixture weight were 800g), and then moisture contents were adjusted to 100% field capacity (-0.33 bar) in the respirometer with vacuum pump. CO2 efflux of each samples was continuously assessed using continuous aeration system (air flow rate 25 cc min-1) using air cylinder during 130hr (at 20° C and darkness condition). The CO2 emitted from the samples were carried to the infrared gas sensor, and these data were sent to a data logger. During the measuring periods, the cumulative CO2 emission were similar between the control (516.8 mg-CO2 kg-1-soil) and BC4 5% mixture (519.3 mg-CO2 kg-1-soil), while BC7 5% mixture was significantly decreased (356.1 mg-CO2 kg-1-soil) compared to other treatment and control. Because the degradation rate of biochar generally increased with decreasing pyrolysis temperature, this result suggest that the soil respiration rates of biochar amended soils are affected by physico-chemical properties of biochar during early incubation periods (about 1 weeks), For example, surface properties of used biochars, which are related to adsorption of soil organic matter and CO2, have different properties with pyrolysis temperature such as specific surface area (BC4=5.08 m2g-1; BC7=260.75 m2 g-1, respectively), average pore diameter (BC4=4,673 nm; BC7=2,606 nm, respectively), and functional groups of biochar surface. However, there was not clear evidence of biochar-mine soil interaction process, because of the short observation periods. Future work should focus on the adsorption of CO2 and soil organic matter of biochar and soil-biochar interaction with long time periods and various biological test.

  9. Preconversion catalytic deoxygenation of phenolic functional groups

    Energy Technology Data Exchange (ETDEWEB)

    Kubiak, C.P.

    1991-01-01

    The deoxygenation of phenols is a conceptually simple, but unusually difficult chemical transformation to achieve. Aryl carbon-oxygen bond cleavage is a chemical transformation of importance in coal liquefaction and the upgrading of coal liquids as well as in the synthesis of natural products. This proposed research offers the possibility of effecting the selective catalytic deoxygenation of phenolic functional groups using CO. A program of research for the catalytic deoxygenation of phenols, via a low energy mechanistic pathway that is based on the use of the CO/CO{sub 2} couple to remove phenolic oxygen atoms, is underway. We are focusing on systems which have significant promise as catalysts: Ir(triphos)OPh, (Pt(triphos)OPh){sup +} and Rh(triphos)OPh. Our studies of phenol deoxygenation focus on monitoring the reactions for the elementary processes upon which catalytic activity will depend: CO insertion into M-OPh bonds, CO{sub 2} elimination from aryloxy carbonyls {l brace}M-C(O)-O-Ph{r brace}, followed by formation of a coordinated benzyne intermediate.

  10. Tailoring biochars from different feedstock and produced at different temperature and time of pyrolysis for their use as soil amendments

    Science.gov (United States)

    Zornoza, Raul; Moreno, Fabian; Acosta, Jose A.; Gomez Lopez, Maria Dolores; Faz, Angel

    2015-04-01

    Biochar used as a soil amendment to improve soil quality and fertility and increase soil carbon sequestration has been the focus of much research in the recent past. Unlike most conventional soil organic materials, which are readily decomposed, the recalcitrant nature of biochar increases its potential value as a soil amending material for the longer term. However, many biochars can be hydrophobic, and added to soil can aggravate water availability in areas where water scarcity is a major limiting factor for agriculture or forestry. It has been shown that biochar characteristics are influenced by production variables, especially feedstock, pyrolysis temperature and time of pyrolysis. Although there have been different studies characterizing biochars prepared from different sources, there are few studies comparing different types of biochar produced from domestic residues, manures or crop residues pyrolysis; there are, in addition, fewer studies dealing with the hydrophobic properties of the biochars. The different feedstock can have different properties which would result into different biochars even produced at the same operational factors. The main objective of this experiment was to study the influence of feedstock properties and pyrolysis temperature and time on nutrient contents, heavy metals, recalcitrance, thermal stability and hydrophobicity of biochars from cotton crop residues (CR), pig manure (PM) and domestic waste (DW). Biochars were obtained by pyrolysis under oxygen-limited conditions in a muffle furnace. The temperature was increased at 5°C min-1 to 300°C, 400°C, 500°C and 700°C and then maintained for 1h, 2h, 4 and 5 h at this temperature. All biochar properties were strongly influenced by feedstock source except for pH, the recalcitrance index and hydrophobicity. Nutrient contents were normally higher in the PM biochar, except for Cu and Ca which were higher in the DW biochar and B in the CR biochar. Heavy metal contents were significantly higher in the DW biochar. Biochar yield was higher in the DW biochar owing to the higher content of ashes. The temperature of pyrolysis did not significantly influence the level of nutrients. However, biochar yield decreased with increasing temperature, while pH increased with increasing temperature. All biochars produced at 300°C and 400°C were highly hydrophobic. Hydrophobicity totally disappeared in all biochars produced over 500°C at 2 h. Thermal stability was highly influenced by pyrolysis temperature, increasing with increasing temperature. Biochar produced at 300°C and 400°C showed presence of different pools of labile and recalcitrant pools, while biochar produced over 500°C showed an acute recalcitrant phase, with low content of labile pools. The disappearance of hydrophobicity was associated with the decreased in the labile pools of the biochar and increased thermal stability. No significant influence of the pyrolysis time was observed in any of the properties studied except for hydrophobicity, which tended to decrease with decreasing the time of pyrolysis. Our results showed that biochars can be tailored for different purposes in terms of the needs of specific nutrients, C sequestration, reduction of the content of toxic heavy metals, or absence of hydrophobicity to avoid negative hydrological processes in the soil. Acknowledgements: This work has been funded by the Programme Young Leaders in Research from Fundación Séneca (Agency of Science and Technology of the Region of Murcia, Spain) through the Project 18920/JLI/13.

  11. A critical view on catalytic pyrolysis of biomass.

    Science.gov (United States)

    Venderbosch, R H

    2015-04-24

    The rapid heating of biomass in an oxygen-free environment optimizes the yield of fast-pyrolysis liquids. This liquid comprises a mix of acids, (dehydrated) carbohydrates, aldehydes, ketones, lignin fragments, aromatics, and alcohols, limiting its use. Deoxygenation of these liquids to replace hydrocarbons represents significant challenges. Catalytic pyrolysis is seen as a promising route to yield liquids with a higher quality. In this paper, literature data on catalytic fast pyrolysis of biomass are reviewed and deoxygenation results correlated with the overall carbon yield. Evidence is given that in an initial stage of the catalytic process reactive components are converted to coke, gas, and water, and only to a limited extent to a liquid product. Catalysts are not yet good enough, and an appropriate combination of pyrolysis conditions, reactive products formed, and different reactions to take place to yield improved quality liquids may be practically impossible. PMID:25872757

  12. Effect of temperature during the spray pyrolysis synthesis of silver nanopowder

    International Nuclear Information System (INIS)

    We report the results of the synthesis and characterization of Ag, AgO, AgNO3 nanopowders or mixtures of them, obtained by spray pyrolysis technique. An aqueous solution of AgNO3 with a concentration of 0.2 mol/L was sprayed through a horizontal tubular furnace where the solvent was evaporated and pyrolytic reaction occurs producing AgNO3, AgO and Ag particles. The synthesis was made at 500, 600 and 700 oC. The obtained material was analyzed by Transmission Electron Microscopy, and the optimal temperature to obtain particles of around 10 nm was 600 oC. The X-rays and Electron Diffraction analysis determined the coexistence of the phases of Ag, AgO and AgNO3, whereas the measurement of x-rays fluorescence the presence of Ag was detected. The solution concentration and the carrier flow, the temperature and the temperature gradient in the furnace influence in the phase and size of the particle.. (author)

  13. Studies on liquefaction and pyrolysis of peat and biomass at KTH

    International Nuclear Information System (INIS)

    A brief review of the study on thermochemical conversion of solid fuels is done. The study have been performed in the Royal Institute of Technology, Stockholm, since the outbreak of energy crisis in the seventies. The main problems connected with utilisation of peat for energy are: 90% moisture content in the deposits and 35-40% oxygen content in the dry substance. Simultaneous dewatering and liquefaction of peat have been achieved by the Bjoerbom method. The wet peat has been treated with CO and H2O without preliminary drying, using water as a medium agent. After treatment water has been phase-separated from the heavy oil product. Another approach is de-oxygenation of peat prior to liquefaction. A significant part of oxygen in peat and biomass can be removed by thermal decomposition of the fuels prior to liquefaction and removal of carbon dioxide and water from the organic matter in them. The products obtained after de-oxygenation demand low consumption of external hydrogenation agent because they are rich in hydrogen. Some criteria for selection of peat as a raw material for liquefaction are given. The equipment and experimental procedure for pyrolysis of peat and biomass are described. A free fall tubular reactor with max operating pressure of 5 MPa and temperature of 1100oC has been used. The effect of treatment conditions under the rapid pyrolysis in the free fall reactor on the yield and the reactivity of char obtained after the final pyrolysis is shown. Peat and wood are transformed into pyrolysis products for less than 1 second; 35-50% of the moisture- and ash-free peat and 70% of the wood have been converted into gaseous products.The char obtained in the rapid pyrolysis contains a fraction which can be further de-volatilized by slow pyrolysis for a few minutes - time much longer than the time for formation of primary products. High reactivity of char is favoured by lower pyrolysis temperature, shorter residence time and larger particle size of the fuel. 3 tabs., 22 refs

  14. Short-Term Effect of Feedstock and Pyrolysis Temperature on Biochar Characteristics, Soil and Crop Response in Temperate Soils

    OpenAIRE

    Victoria Nelissen; Greet Ruysschaert; Dorette Müller-Stöver; Samuel Bodé; Jason Cook; Frederik Ronsse; Simon Shackley; Pascal Boeckx; Henrik Hauggaard-Nielsen

    2014-01-01

    At present, there is limited understanding of how biochar application to soil could be beneficial to crop growth in temperate regions and which biochar types are most suitable. Biochar’s (two feedstocks: willow, pine; three pyrolysis temperatures: 450 °C, 550 °C, 650 °C) effect on nitrogen (N) availability, N use efficiency and crop yield was studied in northwestern European soils using a combined approach of process-based and agronomic experiments. Biochar labile carbon (C) fractions we...

  15. Evaluation of Integrated Time-Temperature Effect in Pyrolysis Process of Historically Contaminated Soils with Cadmium (Cd) and Lead (Pb)

    OpenAIRE

    Bulm?u C; Cocâr?? D. M.; Re?etar-Deac A. M.

    2013-01-01

    It is already known that heavy metals pollution causes important concern to human and ecosystem health. Heavy metals in soils at the European level represents 37.3% between main contaminates affecting soils (EEA, 2007). This paper illustrates results obtained in the framework of laboratory experiments concerning the evaluation of integrated time-temperature effect in pyrolysis process applied to contaminated soil by two different ways: it is about heavy metals historically contaminated soil f...

  16. Short-Term Effect of Feedstock and Pyrolysis Temperature on Biochar Characteristics, Soil and Crop Response in Temperate Soils

    Directory of Open Access Journals (Sweden)

    Victoria Nelissen

    2014-01-01

    Full Text Available At present, there is limited understanding of how biochar application to soil could be beneficial to crop growth in temperate regions and which biochar types are most suitable. Biochar’s (two feedstocks: willow, pine; three pyrolysis temperatures: 450 °C, 550 °C, 650 °C effect on nitrogen (N availability, N use efficiency and crop yield was studied in northwestern European soils using a combined approach of process-based and agronomic experiments. Biochar labile carbon (C fractions were determined and a phytotoxicity test, sorption experiment, N incubation experiment and two pot trials were conducted. Generally, biochar caused decreased soil NO3? availability and N use efficiency, and reduced biomass yields compared to a control soil. Soil NO3? concentrations were more reduced in the willow compared to the pine biochar treatments and the reduction increased with increasing pyrolysis temperatures, which was also reflected in the biomass yields. Woody biochar types can cause short-term reductions in biomass production due to reduced N availability. This effect is biochar feedstock and pyrolysis temperature dependent. Reduced mineral N availability was not caused by labile biochar C nor electrostatic NH4+/NO3? sorption. Hence, the addition of fresh biochar might in some cases require increased fertilizer N application to avoid short-term crop growth retardation.

  17. Effect of pyrolysis temperature on the properties of carbon/nickel nanocomposites prepared by sol-gel method

    Science.gov (United States)

    Mansour, N. Ben; Najeh, I.; Mansouri, S.; El Mir, L.

    2015-05-01

    Carbon-nickel nanocomposites (C/Ni) were prepared by sol-gel method after the incorporation of nickel oxide (NiO) nanoparticles in organic matrix based on pyrogallol-formaldehyde (PF). The nanocomposites heated under inert atmosphere have been characterized by various techniques such as X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), Transmission Electron Microscopy (TEM), and electrical analysis. The XRD spectra exhibited the presence of NiO or metallic Ni phase in amorphous carbon matrix at low pyrolysis temperature, while at 1000 °C the graphite structure line was observed. The TEM images indicate the presence of multiwall carbon nanotubes (MWNT) around Ni nanoparticles for the sample treated at high pyrolysis temperature. The AC conductance shows that our nanocomposites have two behaviors: semiconductor and metal, depending on the pyrolysis temperature. The voltage-current V(I) characteristics of the compound show two different regions: an Ohmic region at low current and a negative differential resistance (NDR) region at higher current. This switching phenomenal behavior has been explained by an electrothermal model.

  18. Evaluation of utilization of corn stalks for energy and carbon material production by using rapid pyrolysis at high temperature

    Energy Technology Data Exchange (ETDEWEB)

    A. Zabaniotou; O. Ioannidou [Aristotle University of Thessaloniki, Thessaloniki (Greece). Chemical Engineering Department

    2008-05-15

    Pyrolysis of agricultural residues (corn stalks) took place batch wise in a laboratory captive sample reactor (wire mesh) at atmospheric pressure. The process was studied by varying the temperature (470-710{sup o}C) with an average heating rate of 60{sup o}C s{sup -1} and a reaction time of 0.2 s. The carrier gas used for both pyrolysis and GC analysis was He. The nature and quantity of gases produced and the main characteristics of the charcoals formed have been determined. From the GC analysis, CO showed the higher yield, followed by H{sub 2}, CH{sub 4} and CO{sub 2}. The increase in temperature is especially important to increase the production of gas, mainly hydrogen. From gas composition and proximate analysis, the heating value of gas and solid phases has been determined. A kinetic model of pyrolysis based on first order kinetics and on total devolatilization has been developed. According to this model, kinetic constants, pre-exponential factors and activation energies have also been determined for low and high temperatures. 26 refs., 9 figs., 3 tabs.

  19. Chemical spray pyrolysis of ?-In2S3 thin films deposited at different temperatures

    Science.gov (United States)

    Sall, Thierno; Marí Soucase, Bernabé; Mollar, Miguel; Hartitti, Bouchaib; Fahoume, Mounir

    2015-01-01

    In2S3 thin films were deposited onto indium tin oxide-coated glass substrates by chemical spray pyrolysis while keeping the substrates at different temperatures. The structures of the sprayed In2S3 thin films were characterized by X-ray diffraction (XFD). The quality of the thin films was determined by Raman spectroscopy. Scanning electron microscopy (SEM) and atomic force microscopy were used to explore the surface morphology and topography of the thin films, respectively. The optical band gap was determined based on optical transmission measurements. The indium sulfide phase exhibited a preferential orientation in the (0, 0, 12) crystallographic direction according to the XRD analysis. The phonon vibration modes determined by Raman spectroscopy also confirmed the presence of the In2S3 phase in our samples. According to SEM, the surface morphologies of the films were free of defects. The optical band gap energy varied from 2.82 eV to 2.95 eV.

  20. PYROLYSIS OF EMPTY FRUIT BUNCHES: INFLUENCE OF TEMPERATURE ON THE YIELDS AND COMPOSITION OF GASEOUS PRODUCT

    OpenAIRE

    Mohamad Azri Sukiran; Loh Soh Kheang; Nasrin Abu Bakar; Choo Yuen May

    2014-01-01

    With the increasing concern on fossil fuel depletion and environmental problems, the utilization of renewable biomass resources is expected to play an important role in the future. Biomass can be converted into a variety of fuels and chemicals by different processes; one of which is pyrolysis that has been subjected to extensive research in recent years. In this study, pyrolysis of oil palm Empty Fruit Bunches (EFB) was investigated using a quartz fluidised-fixed bed reactor. The effects of p...

  1. Deoxygenation of Lake Ikeda, Japan

    Science.gov (United States)

    Nagata, R.; Hasegawa, N.

    2010-12-01

    Lake Ikeda (Kagoshima prefecture, Japan) is a deep lake with a maximum depth of 233 m. Monitoring data of lake Ikeda exist since 1975. We have analyzed the long-term variability in the water conditions of Lake Ikeda. Recently, Lake Ikeda has exhibited the phenomenon of incomplete overturning because of climate warming. The concentrations of DO (dissolved oxygen) in the deepest parts of the lake have reduced. This phenomenon was observed to have started in the 1980s, and gradually, the deepest parts of the lake became anoxic. Later, the anoxic layer became thicker. Currently, winter mixing in Lake Ikeda reaches to depths of only 100 m. According to our simple estimation, the total volume of oxygen in Lake Ikeda will reduce from approximately 70% in the mid-1980s to 40% by the end of 2010. In addition to this phenomenon, the oxygen concentration appears to vary with several years oscillations. The depths to which mixing occurs depends on the severity of the winter, such as the air temperature during the winter season. The mixing period generally occurs in February; hence, the limnological year is considered to start in February. During our analysis period, the total DO mass showed high values in 1996, 2001, and 2003. Air temperature data obtained for regions near Lake Ikeda (the station name is Ibusuki) are used to clarify the cause of the high DO mass values in the three abovementioned years. During the period prior to the occurrence of the high DO mass in February 1996, i.e., in December 1995 and January 1996, the air temperature was low. Similarly, in 2001 and 2003, the air temperature was low in January (one month before the high DO mass was observed). In January 2001 and 2003, the AO (Atlantic Oscillation) index was negative. When the AO index is negative, there tends to be a greater movement of cold polar air into mid-latitudinal regions including Japan (Yamakawa, 2005). This movement induced a low air temperature in Ibusuki, and consequently, a high DO mass was observed in Lake Ikeda. On the other hand, the AO index was negative in December 1995 and January 1996. In addition, the WP (Western Pacific) index was also negative in the winter of 1995/96. When the WP index is negative, Japan experiences a cold winter (Koide and Kodera, 1999; Yasunaka and Hanawa, 2008). Therefore, the combination of the negative phase of AO and the negative phase of WP led to the occurrence of cold surges near Lake Ikeda, which in turn resulted in the high DO mass in February 1996. When DO concentration in the deep layer of the lake becomes higher caused winter mixing, we observe also a reduction in the DO concentration in the surface layer. The DO concentration in the surface layer sometimes decreased to 70%. In future, once Lake Ikeda will deep mixing during very cold winters, the DO concentration in the surface water might reduce largely.

  2. The effects of calcination temperature on the electrochemical performance of LiMnPO4 prepared by ultrasonic spray pyrolysis

    International Nuclear Information System (INIS)

    Research highlights: ? Carbon-coated LiMnPO4 cathode materials were prepared by ultrasonic spray pyrolysis. ? The effects of calcinations temperature on the microstructure and electrochemical performance of C-LiMnPO4 were investigated. ? X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations revealed that the calcination temperature had a strong influence on the morphology and crystallite size of the prepared final powder, and therefore the subsequent electrochemical performance of the material. ? The C-LiMnPO4 powders prepared at 650 oC exhibited excellent electrochemical performance with a discharge capacity of 118 mAh g-1. - Abstract: Carbon-coated LiMnPO4 powders were prepared by ultrasonic spray pyrolysis. The effects of calcination temperature on the microstructure and electrochemical performance of C-LiMnPO4 were investigated. X-ray diffraction (XRD) studies showed that the crystallite size varied with calcination temperature. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations revealed that the calcination temperature had a strong influence on the morphology of the prepared final powder, and therefore the subsequent electrochemical performance of the material. The C-LiMnPO4 powders prepared at 650 oC exhibited excellent electrochemical performance with a dictrochemical performance with a discharge capacity of 118 mAh g-1.

  3. Study of hydrazine deoxygenation in neutral aqueous solution

    International Nuclear Information System (INIS)

    The efficiency of hydrazine deoxygenation added catalyst in the neutral aqueous solution is discussed. The test conditions are selected at temperatures of 10 degree C, 20 degree C and 30 degree C, the initial dissolved oxygen concentration of 10.0-10.8mg/L(10 degree C), 8.2-8.6mg/L(20 degree C) and 7.0-7.4mg/L(30 degree C), and the hydrazine dosages are 6 and 3 times of the initial dissolved oxygen concentration. The results show that the dissolved oxygen concentration can be decreased to be 100 ?g/L when the catalyst dosage is within 600 ?g/L-50?g/L. (authors)

  4. Wettability of poultry litter biochars at variable pyrolysis temperatures and their impact on soil wettability and water retention relationships

    Science.gov (United States)

    Yi, S. C.; Witt, B.; Guo, M.; Chiu, P.; Imhoff, P. T.

    2012-12-01

    To reduce the impact of poultry farming on greenhouse gas emissions, poultry farming waste - poultry litter - can be converted to biofuel and biochar through slow-pyrolysis, with the biochar added to agricultural soil for nutrient enrichment and carbon sequestration. While biochars from source materials other than poultry litter have been shown to sequester carbon and increase soil fertility, there is considerable variability in biochar behavior - even with biochars created from the same source material. This situation is exacerbated by our limited understanding of how biochars alter physical, chemical, and biological processes in agricultural soils. The focus of this work is to develop a mechanistic understanding of how poultry litter (PL) biochars affect the hydrology, microbial communities, N2O emissions, and nitrogen cycling in agricultural soils. The initial focus is on the impact of PL biochar on soil hydrology. PL from Perdue AgriRecycle, LLC (Seaford, Delaware) was used to produce biochars at pyrolysis temperatures from 300°C to 600°C. To explore the impact of these biochars on soil wettability, the PL biochars were mixed with a 30/40 Accusand in mass fractions from 0% to 100%. The water contact angle was then measured using a goniometer on these sand/biochar mixtures using the sessile drop method and a single layer of sample particles. The PL biochars produced at temperatures between 300°C to 400°C were hydrophobic, while those pyrolized at > 400°C were hydrophilic. Water contact angles for samples with 100% biochar varied systematically with pyrolysis temperature, decreasing from 101.12° to 20.57° as the pyrolysis temperature increased from 300 to 600°C. Even for small amounts of hydrophobic biochar added to the hydrophilic sand, the contact angle of the mixture was altered: for sand/biochar mixtures containing only 2% hydrophobic PL biochar by weight, the contact angle of the mixture increased from ~ 8° (0% biochar) to 20° (2% biochar). For higher mass fractions, the impact of hydrophobic PL biochar on the sand/mixture contact angle was more dramatic: for a sand/biochar mixture with 15% PL biochar, the contact angle was 40.12°. Water drop penetration tests were also performed on these samples, and results were consistent with contact angles measured with the sessile drop method. To further explore the cause of the varying contact angle with pyrolysis temperature, the PL biochars were vigorously rinsed with deionized water or heated for 24 hours at 105°C, and the contact angle measurements repeated. Both rinsing and heating samples rendered hydrophobic PL biochar hydrophilic. Rinsate samples were analyzed for total organic carbon and with GC-MS. These data suggest that bio-oils produced during slow-pyrolysis at temperatures < 400°C condensed on biochar and caused hydrophobicity. These bio-oils could be removed through vigorous washing with deionized water or heating to 105°C. The implication of these changes in water contact angle from PL biochar addition on water retention relationships for soil and on water distribution within pores will be discussed.

  5. Effects of Biochar Feedstock and Pyrolysis Temperature on Growth of Corn, Soybean, Lettuce and Carrot

    Science.gov (United States)

    Biochar, the carbon-rich material remaining after pyrolysis (low oxygen) of cellulosic feedstocks, has the potential as a soil amendment to sequester carbon, improve soil water-holding capacity, and increase nutrient retention thereby enhancing soil conditions to benefit plant gr...

  6. Sustainable valorization of plastic wastes for energy with environmental safety via High-Temperature Pyrolysis (HTP) and High-Temperature Steam Gasification (HTSG)

    International Nuclear Information System (INIS)

    In the present study the energetic valorization of electric cable shredder residues (mixed plastics) has been investigated. Thermochemical conversion by means of High-Temperature Steam Gasification (HTSG) and High-Temperature Pyrolysis (HTP) was studied. The effects of temperature and reaction time - process parameters - were investigated. Comparison of the results showed that HTSG seems a more suitable process in terms of produced syngas quality (64%, v/v and 13 MJ/Nm3) than HTP because of higher H2 yield and lower tar content.

  7. Simultaneous recovery of organic and inorganic content of paper deinking residue through low-temperature microwave-assisted pyrolysis.

    Science.gov (United States)

    Zhang, Zhanrong; Macquarrie, Duncan J; Aguiar, Pedro M; Clark, James H; Matharu, Avtar S

    2015-02-17

    Significant amounts of paper deinking residue (DIR) has been and is still being generated from paper deinking processes, representing both an economic and environmental burden for recycled paper mills. Our research on low-temperature (pyrolysis of DIR allows for simultaneously efficient fast separation and recovery of the organic and inorganic content of DIR at relatively low temperature and within 15 min. Our study is the first highly detailed account of the use low-temperature MW-assisted pyrolysis to effect this change. The obtained liquid and solid products were characterized by a variety of analytical techniques (e.g., attenuated total reflection infrared, gas chromatography-mass spectrometry, liquid-state nuclear magnetic resonance (NMR), X-ray diffraction, solid-state cross-polarization/magic-angle spinning (13)C NMR, and Bloch-decay (13)C NMR). The results reveal that the process efficiently separates the inorganic minerals as microwave residue (mainly calcite and kaolinite) from organic matter, and hence the microwave residue could be reused to produce new paper/cardboard products. The organic fraction bio-oil generated is energy-densified and rich in carbohydrates and is a potential source for valuable aromatic compounds. PMID:25590264

  8. Interactive effects of biochar ageing in soils related to feedstock, pyrolysis temperature, and historic charcoal production.

    Science.gov (United States)

    Heitkötter, Julian; Marschner, Bernd

    2015-04-01

    Biochar is suggested for soil amelioration and carbon sequestration, based on its assumed role as the key factor for the long-term fertility of Terra preta soils. Several studies have shown that certain biochar properties can undergo changes through ageing processes, especially regarding charge characteristics. However, only a few studies determined the changes of different biochars under the same incubation conditions and in different soils. The objective of this study was to characterize the changes of pine chip (PC)- and corn digestate (CD)-derived biochars pyrolyzed at 400 or 600 °C during 100 days of laboratory incubation in a historical kiln soil and an adjacent control soil. Separation between soil and biochar was ensured by using mesh bags. Especially, changes in charge characteristics depended on initial biochar properties affected by feedstock and pyrolysis temperature and on soil properties affected by historic charcoal production. While the cation exchange capacity (CEC) markedly increased for both CD biochars during incubation, PC biochars showed no or only slight increases in CEC. Corresponding to the changes in CEC, ageing of biochars also increased the amount of acid functional groups with increases being in average about 2-fold higher in CD biochars than in PC biochars. Further and in contrast to other studies, the surface areas of biochars increased during ageing, likely due to ash leaching and degradation of tar residues. Changes in CEC and surface acidity of CD biochars were more pronounced after incubation in the control soil, while surface area increase was higher in the kiln soil. Since the two acidic forest soils used in this this study did not greatly differ in physical or chemical properties, the main process for inducing these differences in the buried biochar most likely is related to the differences in dissolved organic carbon (DOC). Although the kiln soil contained about 50% more soil organic carbon due to the presence of charcoal particles, extractable DOC was lower and less aromatic than in the adjacent control soil, likely due to strong sorption of dissolved organic matter (DOM) onto charcoal particles. We suggest that higher sorption of DOM onto the surface of biochar in the control soil provided additional acid functional groups and thus increased the surface charge to a greater extent than in the DOC poorer kiln soil. Hence, biochars incubated in the kiln soil showed less changes in CEC and surface acidity. Higher availability of DOM in the control soil could also stimulate microbial activity to a larger extent, resulting in higher oxidation rates of biochars incubated in the control soil.

  9. Hydrogen-rich gas production from waste plastics by pyrolysis and low-temperature steam reforming over a ruthenium catalyst

    International Nuclear Information System (INIS)

    Operating conditions for low-temperature pyrolysis and steam reforming of plastics over a ruthenium catalyst were investigated. In the range studied, the highest gas and lowest coke fractions for polystyrene (PS) with a 60 g h-1 scale, continuous-feed, two-stage gasifier were obtained with a pyrolyzer temperature of 673 K, steam reforming temperature of 903 K, and weight hourly space velocity (WHSV) of 0.10 g-sample g-catalyst-1 h-1. These operating conditions are consistent with optimum conditions reported previously for polypropylene. Our results indicate that at around 903 K, the activity of the ruthenium catalyst was high enough to minimize the difference between the rates of the steam reforming reactions of the pyrolysates from polystyrene and polypropylene. The proposed system thus has the flexibility to compensate for differences in chemical structures of municipal waste plastics. In addition, the steam reforming temperature was about 200 K lower than the temperature used in a conventional Ni-catalyzed process for the production of hydrogen. Low-temperature steam reforming allows for lower thermal input to the steam reformer, which results in an increase in thermal efficiency in the proposed process employing a Ru catalyst. Because low-temperature steam reforming can be also expected to reduce thermal degradation rates of the catalyst, the pyrolysis-steam reforming process with a Ru catalyst has the potential for use in small-sclyst has the potential for use in small-scale production of hydrogen-rich gas from waste plastics that can be used for power generation.

  10. Effect of the flame temperature on the characteristics of zirconium oxide fine particle synthesized by flame assisted spray pyrolysis

    Science.gov (United States)

    Widiyastuti, W.; Machmudah, Siti; Nurtono, Tantular; Winardi, Sugeng

    2013-09-01

    Zirconium oxide fine particles were synthesized by flame assisted spray pyrolysis using zirconium chloride solution as precursor. Propane gas and air were used as a fuel and an oxidizer, respectively. The ratio of flow rate of oxidizer and fuel was maintained constant at 10:1 to ensure a complete combustion. Increasing fuel flow rate led to the increase of temperature distribution in the flame reactor. The intensity of XRD patterns increased with temperature and precursor concentration. Phase composition of zirconium oxide produced by this process consisted of monoclinic and tetragonal phases. The volume fraction of monoclinic phase of zirconium oxide increased with temperature and precursor concentration. The morphology particles observed by SEM resulted in spherical particles with size in the submicron range depending on the precursor concentration.

  11. Pyrolysis and gasification of coal at high temperatures. Quarterly progress report No. 9, September 15, 1989--December 15, 1989

    Energy Technology Data Exchange (ETDEWEB)

    Zygourakis, K.

    1989-12-31

    Coals of different ranks will be pyrolyzed in a microscope hot-stage reactor using inert and reacting atmospheres. The macropore structure oft he produced chars will be characterized using video microscopy and digital image processing techniques to obtain pore size distributions. Comparative studies will quantify the effect of pyrolysis conditions (heating rates, final heat treatment temperatures, particle size and inert or reacting atmosphere) on the pore structure of the devolatilized chars. The devolatilized chars will be gasified in the regime of strong intraparticle diffusional limitations using O{sub 2}/N{sub 2} and O{sub 2}/H{sub 2}/N{sub 2} mixtures. Constant temperature and programmed-temperature experiments in a TGA will be used for these studies. Additional gasification experiments performed in the hot-stage reactor will be videotaped and selected images will be analyzed to obtain quantitative data on particle shrinkage and fragmentation.

  12. Bio-oil and bio-char from low temperature pyrolysis of spent grains using activated alumina.

    Science.gov (United States)

    Sanna, Aimaro; Li, Sujing; Linforth, Rob; Smart, Katherine A; Andrésen, John M

    2011-11-01

    The pyrolysis of wheat and barley spent grains resulting from bio-ethanol and beer production respectively was investigated at temperatures between 460 and 540 °C using an activated alumina bed. The results showed that the bio-oil yield and quality depend principally on the applied temperature where pyrolysis at 460 °C leaves a bio-oil with lower nitrogen content in comparison with the original spent grains and low oxygen content. The viscosity profile of the spent grains indicated that activated alumina could promote liquefaction and prevent charring of the structure between 400 and 460 °C. The biochar contains about 10-12% of original carbon and 13-20% of starting nitrogen resulting very attractive as a soil amendment and for carbon sequestration. Overall, value can be added to the spent grains opening a new market in bio-fuel production without the needs of external energy. The bio-oil from spent grains could meet about 9% of the renewable obligation in the UK. PMID:21930374

  13. Pyrolysis of tyre wastes

    OpenAIRE

    Fernández Fernández, Ana M.ª; Díez Díaz-Estébanez, M.ª Antonia; Álvarez García, Ramón; Barriocanal Rueda, Carmen

    2009-01-01

    Two products obtained from the mechanical grinding of scrap tyres are the subject of the present study: granulated rubber and textile fibres used as tyre reinforcement. The two wastes were subjected to pyrolysis in a thermobalance and pyrolysis in a horizontal oven up to two final temperatures (550 °C and 900 °C) in order to obtain a char, condensable products (oil) and a gas. The oil and the gas were analysed by gas chromatography.

  14. PYROLYSIS OF WOODY MATERIAL

    OpenAIRE

    Martin Bajus

    2010-01-01

    This work aimed to study the recovery of beech wood by the process of pyrolysis. The effects ofexperimental conditions in products yield and composition were studied. The thermal behaviour offorestry biomass was studied in a batch reactor at temperatures ranging from 350oC to 450oC. Thereaction time of wood thermal degradation took 95 min. The main objective was the identificationof the oxygenates and carbonaceous species generated by pyrolysis of beech wood. The productsof wood cracking were...

  15. On the application of hydrazine for deoxygenation of WWER primary circuit water coolant during oritages

    International Nuclear Information System (INIS)

    Possibility and conditions of effective hydrazine usage for correction of coolant composition of the WWER first circuit during outages for decreasing water corrosivity was considered. Experimental investigations have confirmed possibility of hydrazine usage for deoxygenation of the irradiated water which interacts with nitrates and nitrites formed as a result of ammonia oxidation. Taking account of catalytic effect of ionizing radiation, coolant treatment with hydrazine during outages may be performed at low temperature

  16. Chemical composition and temperature dependent performance of ZnO-thin film transistors deposited by pulsed and continuous spray pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Ortel, Marlis; Balster, Torsten; Wagner, Veit [School of Engineering and Science, Jacobs University Bremen, Campus Ring 1, 28759 Bremen (Germany)

    2013-12-21

    Zinc oxide thin film transistors (TFTs) deposited by continuous and pulsed spray pyrolysis were investigated to analyze process kinetics which make reduction of process temperature possible. Thus, fluid mechanics, chemical composition, electrical performance, and deposition and annealing temperature were systematically analyzed. It was found that ZnO layers continuously deposited at 360?°C contained zinc oxynitrides, CO{sub 3}, and hydro carbonate groups from pyrolysis of basic zinc acetate. Statistically, every second wurtzite ZnO unit cell contained an impurity atom. The purity and performance of the ZnO-TFTs increased systematically with increasing deposition temperature due to an improved oxidation processes. At 500?°C the zinc to oxygen ratio exceeded a high value of 0.96. Additionally, the ZnO film was not found to be in a stabilized state after deposition even at high temperatures. Introducing additional subsequent annealing steps stabilizes the film and allows the reduction of the overall thermal stress to the substrate. Further improvement of device characteristics was obtained by pulsed deposition which allowed a more effective transport of the by-products and oxygen. A significant reduction of the deposition temperature by 140?°C was achieved compared to the same performance as in continuous deposition mode. The trap density close to the Fermi energy could be reduced by a factor of two to 4?×?10{sup 17}?eV{sup ?1}?cm{sup ?3} due to the optimized combustion process on the surface. The optimization of the deposition processes made the fabrication of TFTs with excellent performance possible. The mobility was high and exceeded 12 cm{sup 2}/V s, the subthreshold slope was 0.3 V dec{sup ?1}, and an on-set close to the ideal value of 0?V was achieved.

  17. Chemical composition and temperature dependent performance of ZnO-thin film transistors deposited by pulsed and continuous spray pyrolysis

    International Nuclear Information System (INIS)

    Zinc oxide thin film transistors (TFTs) deposited by continuous and pulsed spray pyrolysis were investigated to analyze process kinetics which make reduction of process temperature possible. Thus, fluid mechanics, chemical composition, electrical performance, and deposition and annealing temperature were systematically analyzed. It was found that ZnO layers continuously deposited at 360?°C contained zinc oxynitrides, CO3, and hydro carbonate groups from pyrolysis of basic zinc acetate. Statistically, every second wurtzite ZnO unit cell contained an impurity atom. The purity and performance of the ZnO-TFTs increased systematically with increasing deposition temperature due to an improved oxidation processes. At 500?°C the zinc to oxygen ratio exceeded a high value of 0.96. Additionally, the ZnO film was not found to be in a stabilized state after deposition even at high temperatures. Introducing additional subsequent annealing steps stabilizes the film and allows the reduction of the overall thermal stress to the substrate. Further improvement of device characteristics was obtained by pulsed deposition which allowed a more effective transport of the by-products and oxygen. A significant reduction of the deposition temperature by 140?°C was achieved compared to the same performance as in continuous deposition mode. The trap density close to the Fermi energy could be reduced by a factor of two to 4?×?1017?eV?1?cm?3 due to the optimized combustion process on the surface. The optimization of the deposition processes made the fabrication of TFTs with excellent performance possible. The mobility was high and exceeded 12 cm2/V s, the subthreshold slope was 0.3 V dec?1, and an on-set close to the ideal value of 0?V was achieved

  18. Study of hydrodeoxygenation of bio-oil from the fast pyrolysis of biomass

    Energy Technology Data Exchange (ETDEWEB)

    Su-ping, Z. [ECUST, Shanghai (China). Dept. of Chemical Engineering for Energy Resources

    2003-01-01

    The bio-oil obtained from the fast pyrolysis of biomass has a high oxygen content. Ketones and aldehydes, carboxylic acids and esters, aliphatic and aromatic alcohols, and ethers have been detected in significant quantities. Because of the reactivity of oxygenated groups, the main problems of the oil are instability. Therefore study of the deoxygenation of bio-oil is needed. In the present work the mechanism of hydrodeoxygenation (HDO) of bio-oil in the presence of a cobalt molybdate catalyst was studied. Particularly, the effects of reaction time, temperature, and hydrogen pressure on the HDO activity were examined. On the experimental results, a kinetic model for HDO of bio-oil was proposed. (author)

  19. Bench-Scale Design of a Low-Temperature Pyrolysis and Steam Reforming System for the Treatment of Uranium-Bearing Spent TBP

    International Nuclear Information System (INIS)

    Spent TBP, a combustible waste solvent, is not readily incinerated due to problems associated with condensation of phosphoric acid. A two-stage pyrolysis system that consists of a low-temperature pyrolysis at ? 450 .deg. C and a higher-temperature steam-assisted pyrolysis at ? 800 .deg .C has been proposed as an alternative oxidation technology for the destruction of spent TBP. Off-gas from this two-stage pyrolysis system includes various unburned hydrocarbons (UHCs) as well as complete-steam reforming products, CO and H2, which should be substantially oxidized prior to emission into the atmosphere. Catalytic oxidation is considered as an advantageous and safe treatment method for UHCs. A Pt-based honeycomb monolith is considered to be an effective combustion catalyst for UHCs. Numerous studies on platinum monolith honeycomb reactors have focused on catalytic combustion of a single fuel. The present study investigated the catalytic oxidation of a mixture of various UHCs from the proposed two-stage pyrolysis of waste TBP, in a platinum monolith honeycomb reactor. A wide ranging parametric model study was performed to establish proper conditions of a platinum monolith honeycomb reactor for the bench-scale system design

  20. Effect of gamma-ray irradiation on the deoxygenation of salt-containing water using hydrazine

    International Nuclear Information System (INIS)

    In spent fuel pools at the Fukushima Daiichi nuclear power plant, hydrazine was added to salt-containing water in order to reduce dissolved oxygen. Hydrazine is known to reduce dissolved oxygen in high-temperature pure water, but its deoxygenation behavior in salt-containing water at ambient temperature in the presence of radiation is unknown. Deoxygenation using hydrazine in salt-containing water was thus investigated using a 60Co gamma-ray source and artificial seawater at room temperature. Water samples containing a small amount of hydrazine were irradiated at dose rates of 100 - 10,000 Gy/h. The concentration of dissolved oxygen in the water samples was measured before and after irradiation. Notably, a decrease in the dissolved oxygen was only observed after irradiation, and the dissolved oxygen concentration decreased with increasing dose rate and irradiation time. The rate of decrease in the amount of dissolved oxygen using hydrazine was slow in the presence of salts. Kinetic considerations suggested that the deoxygenation of the salt-containing water exposed to gamma-ray irradiation using hydrazine was suppressed by chloride ions. (author)

  1. Deoxygenation of Plant Fatty Acid using NiSnK/ SiO2 as Catalyst

    International Nuclear Information System (INIS)

    Environmental friendly bio-oil which offers supply reliability as a potential alternative fuel, has spurred to rapid development of bio fuels technology. Palm oil is a potential renewable energy source for bio fuels production in the future and Malaysia is one of the world largest palm oil producers. However, undesired oxygen content in the plant fatty acid that contributes to low energy density, high viscosity, and low stability, makes the palm oil not effective to be used as bio fuels directly. In the present study, the performance of silica supported trimetal catalyst, NiSnK/ SiO2, on deoxygenation of used palm oil was evaluated. In addition, the effects of operating parameters, such as reaction temperature and weight hourly space velocity were investigated. Conversion of palmitic acid as high as 90 % was achieved in deoxygenation of used palm oil at reaction temperature 350 degree Celsius. In order to have a better understanding on the deoxygenation reaction, model compound system using the major saturated fatty acid in the used palm oil, palmitic acid was also carried out. Palmitic acid was found mainly decarboxylated into n-pentadecane with some decarboxylation and isomerization products. (author)

  2. Preconversion catalytic deoxygenation of phenolic functional groups. Quarterly technical progress report, April 1, 1992--June 30, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Kubiak, C.P.

    1992-11-01

    Aryl carbon-oxygen bond cleavage is a chemical transformation of importance in coal liquefaction and the upgrading of coal liquids as well as in the synthesis of natural products. There have been numerous attempts to discover general methods for the cleavage of aryl carbon-oxygen bonds. All the stoichiometric organic methods for phenol deoxygenation have limited applications and involve expensive reagents. Catalytic method, for the hydrodeoxygenation (HDO) of phenols involve supported transition metal oxides, such as Mo/{gamma}-Al{sub 2}O{sub 3}, Ni-MO/{gamma}-Al{sub 2}O{sub 3}, Co-Mo/{gamma}-Al{sub 2}O{sub 3}, and Fe{sub 2}O{sub 3}/SiO{sub 2}. Typical phenol hydrodeoxygenation conditions involve hydrogen pressures in excess of 100 atm and temperatures in excess of 200{degrees}C. Under these conditions arene ring hydrogenation is generally found to compete with phenol deoxygenation; and the coproduct water is found to impair the activity of the catalysts. This proposed research offers the possibility of effecting the selective catalytic deoxygenation of phenolic functional groups using CO. The deoxygenation of phenols by carbon monoxide mediated by Ir(triphos)OAr has provided us with a catalytic Phenol deoxygenation pathway, through the elimination of CO{sub 2} and formation of a benzyne intermediate. Although the [Pt(triphos)(O-Ph-Me)]PF{sub 6} system is not expected to be as efficient a catalyst as some of the other transition metals systems we are currently exploring, it will provide more information about the deoxygenation mechanism in these triphos complexes. This is due to the presence of the structurally sensitive {sup 3l}P--{sup 195}Pt coupling constant and comparisons to the extensively studied Pt(dppe)(O-Ph){sub 2} systems.

  3. Ocean (Deoxygenation Across the Last Deglaciation: Insights for the Future

    Directory of Open Access Journals (Sweden)

    Samuel L. Jaccard

    2014-03-01

    Full Text Available Anthropogenic warming is expected to drive oxygen out of the ocean as the water temperature rises and the rate of exchange between subsurface waters and the atmosphere slows due to enhanced upper ocean density stratification. Observations from recent decades are tantalizingly consistent with this prediction, though these changes remain subtle in the face of natural variability. Earth system model projections unanimously predict a long-term decrease in the global ocean oxygen inventory, but show regional discrepancies, particularly in the most oxygen-depleted waters, owing to the complex interplay between oxygen supply pathways and oxygen consumption. The geological record provides an orthogonal perspective, showing how the oceanic oxygen content varied in response to prior episodes of climate change. These past changes were much slower than the current, anthropogenic change, but can help to appraise sensitivities, and point toward potentially dominant mechanisms of change. Consistent with the model projections, marine sediments recorded an overall expansion of low-oxygen waters in the upper ocean as it warmed at the end of the last ice age. This expansion was not linearly related with temperature, though, but reached a deoxygenation extreme midway through the warming. Meanwhile, the deep ocean became better oxygenated, opposite the general expectation. These observations require that significant changes in apparent oxygen utilization occurred, suggesting that they will also be important in the future.

  4. Effect of Substrate Temperature on the Growth of Polycrystalline ZnS Thin Films Prepared by Spray Pyrolysis Technique

    Directory of Open Access Journals (Sweden)

    R. Chandiramouli

    2012-01-01

    Full Text Available ZnS thin films on glass substrate have been prepared by home built spray pyrolysis technique at 220, 250 and 280°C. Aqueous solution of 50 mL containing zinc acetate dihydrate and thiourea salts of 1:1 M is sprayed as fine mist at a pressure of 2 kg cm-2 with flow rate of 3 mL min-1 on preheated glass substrate. Film obtained at 220°C found to be amorphous and polycrystalline at 250 and 280°C with preferential orientation along (111 plane. X-ray line broadening technique is utilized to determine the grain size and microstrain of the ZnS film. Compositional studies indicate the presence of oxygen for the film prepared at 250°C. The effect of substrate temperature on crystalline structure, surface morphology and composition were analyzed and reported.

  5. Structural evolution and optical characterization of indium doped cadmium sulfide thin films obtained by spray pyrolysis for different substrate temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Acosta, Dwight R.; Magana, Carlos R.; Martinez, Arturo I. [UNAM, Instituto de Fisica, Mexico City (Mexico); Maldonado, Arturo [CINVESTAV, Dept. de Ingenieria Electrica, Mexico City (Mexico)

    2004-05-01

    Indium doped cadmium sulfide thin films were prepared by spray pyrolysis on glass substrates at different temperatures ranging from 300 deg C to 450 deg C in 25 deg C steps, using aqueous solution of copper chloride and thiourea salts. We used In(COOH){sub 3} as the dopant. Structural characterization was carried out by X-ray diffractometry and scanning electron microscopy and high resolution electron microscopy were used together with atomic force microscopy (AFM) to follow the evolution of structural and morphological parameters of the films with substrate temperature (T{sub s}), At least two preferential growth, (1 1 2) for samples with T{sub s} between 325 deg C and 400 deg C and (0 0 2) for T{sub s} between 400 deg C and 450 deg C, respectively were detected. For the films obtained at higher substrate temperatures, HREM micrographs revealed the presence of a large number of structural defects together with nanostructured configurations. AFM revealed surface modifications of CdS:In grains at higher substrate temperature. The substrate temperature is directly related with the shift detected in the band gap values derived from optical of parameters. (Author)

  6. Large-scale reactive molecular dynamics simulation and kinetic modeling of high-temperature pyrolysis of the Gloeocapsomorphaprisca microfossils.

    Science.gov (United States)

    Zou, Chenyu; Raman, Sumathy; van Duin, Adri C T

    2014-06-12

    The ability to predict accurately the thermal conversion of complex carbonaceous materials is of value in both petroleum exploration and refining operations. Modeling the thermal cracking of kerogen under basinal heating conditions improves the predrill prediction of oil and gas yields and quality, thereby ultimately lowering the exploration risk. Modeling the chemical structure and reactivity of asphaltene from petroleum vacuum residues enables prediction of coke formation and properties in refinery processes, thereby lowering operating cost. The chemical structure-chemical yield modeling (CS-CYM) developed by Freund et al. is more rigorous, time-consuming, and requires a great deal of chemical insight into reaction network and reaction kinetics. The present work explores the applicability of a more fundamental atomistic simulation using the quantum mechanically based reactive force field to predict the product yield and overall kinetics of decomposition of two biopolymers, namely, the Kukersite and Gutternberg. Reactive molecular dynamics (RMD) simulations were performed on systems consisting of 10(4) to 10(5) atoms at different densities and temperatures to derive the overall kinetic parameters and a lumped kinetic model for pyrolysis. The kinetic parameters derived from the simulated pyrolysis of an individual component and the mixture of all four components in Guttenberg reveal the role of cross-talk between the fragments and enhanced reactivity of component A by radicals from other components. The Arrhenius extrapolation of the model yields reasonable prediction for the overall barrier for cracking. Because simulations were run at very high temperature (T > 1500 K) to study cracking within the simulation time of up to 1 ns, it, however, led to the entropically favored ethylene formation as a dominant decomposition route. Future work will focus on evaluating the applicability of accelerated reactive MD approaches to study cracking. PMID:24821589

  7. Temperature dependence of the photoluminescence spectra of CdS: In thin films prepared by the spray pyrolysis technique

    Energy Technology Data Exchange (ETDEWEB)

    Ikhmayies, Shadia J., E-mail: shadia_ikhmayies@yahoo.com [Al Isra University, Faculty of Information Technology, Department of Basic Sciences-Physics, Amman 16197 (Jordan); Ahmad-Bitar, Riyad N., E-mail: riyad_b@yahoo.com [University of Jordan, Faculty of Science, Physics Department, Amman 1192 (Jordan)

    2013-10-15

    Indium doped cadmium sulfide thin films (CdS:In) are prepared by the spray pyrolysis technique on glass substrates using a home-made spraying system at a substrate temperature T{sub s}=490 °C. The photoluminescence (PL) spectra are recorded at different temperatures in the range 24–160 K. Two broad peaks were observed; a strong one in the visible region centered on E?2.0 eV and a weak one in the infrared region centered on E?1.06 eV. The first one is deconvoluted into two Gaussian peaks corresponding to the yellow and red bands, and the second one is deconvoluted into one Gaussian peak corresponding to the infrared band. A strong quenching of the PL intensity with temperature is observed after T=60 K for the yellow and infrared bands and after T=90 K for the red band. The activation energy E{sub a} was estimated by using the Arrhenius plot for the different bands. The estimated values for the three bands lie in the range E{sub a}?23.4–27.3 meV. The peak positions of the yellow and red bands are red-shifted after T=90 K, while the peak position of the infrared band is blue shifted in the whole temperature range. The full width at half maximum (FWHM) for the three bands increases with temperature. According to these findings the three bands are explained in terms of bound excitons. -- Highlights: • The photoluminescence (PL) of sprayed CdS:In thin films is recorded at different temperatures. • The PL spectrum is deconvoluted to three Gaussian peaks corresponding to yellow, red and infrared bands. • The decrease of the PL intensity with temperature for these bands has similar behaviors. • The yellow and red bands are red-shifted with temperature, but the infrared band is blue-shifted. • From the Arrhenius plots the activation energy is estimated.

  8. Temperature dependence of the photoluminescence spectra of CdS: In thin films prepared by the spray pyrolysis technique

    International Nuclear Information System (INIS)

    Indium doped cadmium sulfide thin films (CdS:In) are prepared by the spray pyrolysis technique on glass substrates using a home-made spraying system at a substrate temperature Ts=490 °C. The photoluminescence (PL) spectra are recorded at different temperatures in the range 24–160 K. Two broad peaks were observed; a strong one in the visible region centered on E?2.0 eV and a weak one in the infrared region centered on E?1.06 eV. The first one is deconvoluted into two Gaussian peaks corresponding to the yellow and red bands, and the second one is deconvoluted into one Gaussian peak corresponding to the infrared band. A strong quenching of the PL intensity with temperature is observed after T=60 K for the yellow and infrared bands and after T=90 K for the red band. The activation energy Ea was estimated by using the Arrhenius plot for the different bands. The estimated values for the three bands lie in the range Ea?23.4–27.3 meV. The peak positions of the yellow and red bands are red-shifted after T=90 K, while the peak position of the infrared band is blue shifted in the whole temperature range. The full width at half maximum (FWHM) for the three bands increases with temperature. According to these findings the three bands are explained in terms of bound excitons. -- Highlights: • The photoluminescence (PL) of sprayed CdS:In thin films is recorded at different temperatures. • The PL spectrum is deconvoluted to three Gaussian peaks corresponding to yellow, red and infrared bands. • The decrease of the PL intensity with temperature for these bands has similar behaviors. • The yellow and red bands are red-shifted with temperature, but the infrared band is blue-shifted. • From the Arrhenius plots the activation energy is estimated

  9. The impacts of pyrolysis temperature and feedstock type on biochar properties and the effects of biochar application on the properties of a sandy loam

    Science.gov (United States)

    Aston, Steve; Doerr, Stefan; Street-Perrott, Alayne

    2013-04-01

    The production of biochar and its application to soil has the potential to make a significant contribution to climate change mitigation whilst simultaneously improving soil fertility, crop yield and soil water-holding capacity. Biochar is produced from various biomass feedstock materials at varying pyrolysis temperatures, but relatively little is known about how these parameters affect the properties of the resultant biochars and their impact on the properties of the soils to which they are subsequently applied. Salix viminalis, M. giganteus and Picea sitchensis feedstocks were chipped then sieved to 2 - 5 mm, oven dried to constant weight, then pyrolyzed at 350, 500, 600 and 800° C in a nitrogen-purged tube furnace. Biochar yields were measured by weighing the mass of each sample before and after pyrolysis. Biochar hydrophobicity was assessed by using a goniometer to measure water-droplet contact-angles. Cation-exchange-capacity (CEC) was measured using the ammonium acetate method. Biochars were also produced in a rotary kiln from softwood pellets at 400, 500, 600 and 700° C then ground to 0.4 - 1 mm and applied to a sandy loam at a rate of 50 g kg-1. Bulk densities of these soil-biochar mixtures were measured on a tapped, dry, basis. The water-holding-capacity (WHC) of each mixture was measured gravimetrically following saturation and free-draining. The filter paper method was used to assess how pyrolysis temperature influences the effect of biochar application on matric suction. For all feedstocks, large decreases in biochar yield were observed between the pyrolysis temperatures of 350° C and 500° C. For Salix viminalis and M. giganteus feedstocks, subsequent reductions in the yield with increasing pyrolysis temperature were much lower. There were significant differences in hydrophobicity between biochars produced from different biomass and mean biochar hydrophobicity decreased with increasing pyrolysis temperature for all feedstocks. Results for CEC and WHC measurements will also be presented. With water contents of 0.04, 0.08 and 0.16 cm3 cm-3, the mean matric suctions of a sandy loam were higher when biochar was added. However, the differences were only statistically significant at a water content of 0.16 cm3 cm-3, where biochar produced at 500° C had the highest suction. Biochar additions always lowered the mean bulk density of a sandy loam, but there were significant differences in the extent to which biochars produced at different temperatures did this. Biochar yields and hydrophobicity vary according to feedstock type and decrease with increasing pyrolysis temperature. Application of biochar can significantly reduce bulk density but the extent of this effect varies according to the pyrolysis temperature at which the biochar is produced. Pyrolysis temperature can have a significant influence on how biochars affect soil suction. Acknowledgements: This study was funded by a UK Natural Environment Research Council (NERC) Doctoral Training Grant: NE/H525154/1.

  10. Catalytic pyrolysis using UZM-39 aluminosilicate zeolite

    Energy Technology Data Exchange (ETDEWEB)

    Nicholas, Christpher P; Boldingh, Edwin P

    2013-12-17

    A new family of coherently grown composites of TUN and IMF zeotypes has been synthesized and show to be effective catalysts for catalytic pyrolysis of biomass. These zeolites are represented by the empirical formula. Na.sub.nM.sub.m.sup.n+R.sub.rQ.sub.qAl.sub1-xE.sub.xSi.sub.yO.s- ub.z where M represents zinc or a metal or metals from Group 1, Group 2, Group 3 or the lanthanide series of the periodic table, R is an A,.OMEGA.-dihalosubstituted paraffin such as 1,4-dibromobutane, Q is a neutral amine containing 5 or fewer carbon atoms such as 1-methylpyrrolidine and E is a framework element such as gallium. The process involves contacting a carbonaceous biomass feedstock with UZM-39 at pyrolysis conditions to produce pyrolysis gases comprising hydrocarbons. The catalyst catalyzes a deoxygenation reaction converting oxygenated hyrdocarbons into hydrocarbons removing the oxygen as carbon oxides and water. A portion of the pyrolysis gases is condensed to produce low oxygen biomass-derived pyrolysis oil.

  11. Catalytic pyrolysis using UZM-39 aluminosilicate zeolite

    Science.gov (United States)

    Nicholas, Christopher P; Boldingh, Edwin P

    2014-10-07

    A new family of coherently grown composites of TUN and IMF zeotypes has been synthesized and shown to be effective catalysts for catalytic pyrolysis of biomass. These zeolites are represented by the empirical formula. Na.sub.nM.sub.m.sup.n+R.sub.rQ.sub.qAl.sub.1-xE.sub.xSi.sub.yO.s- ub.z where M represents zinc or a metal or metals from Group 1, Group 2, Group 3 or the lanthanide series of the periodic table, R is an A,.OMEGA.-dihalosubstituted paraffin such as 1,4-dibromobutane, Q is a neutral amine containing 5 or fewer carbon atoms such as 1-methylpyrrolidine and E is a framework element such as gallium. The process involves contacting a carbonaceous biomass feedstock with UZM-39 at pyrolysis conditions to produce pyrolysis gases comprising hydrocarbons. The catalyst catalyzes a deoxygenation reaction converting oxygenated hydrocarbons into hydrocarbons and removing the oxygen as carbon oxides and water. A portion of the pyrolysis gases is condensed to produce low oxygen biomass-derived pyrolysis oil.

  12. Biohydrogen production from kitchen based vegetable waste: effect of pyrolysis temperature and time on catalysed and non-catalysed operation.

    Science.gov (United States)

    Agarwal, Manu; Tardio, James; Mohan, S Venkata

    2013-02-01

    Pyrolysis of kitchen based vegetable waste (KVW) was studied in a designed packed bed reactor. The effect of process parameters like temperature, time and catalyst on bio-gas yield and its composition was studied. The total bio-gas yield was found to be maximum with non-catalysed operation (260ml/g) at 1073K (180min). Higher hydrogen (H(2)) yield with non-catalysed operation (32.68%) was observed at 1073K (180min) while with catalysed operation the requisite temperature (873K) and time (120min) reduced with both silica gel (33.34%) and sand (41.82%) thus, saving energy input. Methane (CH(4)) yield was found to be highest (4.44times than non-catalysed and 1.42 with silica gel) in presence of sand (71.485ml/g) at medium temperature (873K) and time (60min). The catalyst operation reduced the carbondioxide (CO(2)) share from 47.29% to 41.30% (silica gel catalysed) and 21.91% (sand catalysed) at 873K. PMID:23313698

  13. Catalytic pyrolysis of Laminaria japonica over nanoporous catalysts using Py-GC/MS

    OpenAIRE

    Lee, Hyung Won; Jeon, Jong-Ki; Park, Sung Hoon; Jeong, Kwang-Eun; Chae, Ho-Jeong; Park, Young-Kwon

    2011-01-01

    The catalytic pyrolysis of Laminaria japonica was carried out over a hierarchical meso-MFI zeolite (Meso-MFI) and nanoporous Al-MCM-48 using pyrolysis gas chromatography/mass spectrometry (Py-GC/MS). The effect of the catalyst type on the product distribution and chemical composition of the bio-oil was examined using Py-GC/MS. The Meso-MFI exhibited a higher activity in deoxygenation and aromatization during the catalytic pyrolysis of L. japonica. Meanwhile, the catalytic activity of Al-MCM-4...

  14. Catalytic pyrolysis of Laminaria japonica over nanoporous catalysts using Py-GC/MS

    Directory of Open Access Journals (Sweden)

    Jeon Jong-Ki

    2011-01-01

    Full Text Available Abstract The catalytic pyrolysis of Laminaria japonica was carried out over a hierarchical meso-MFI zeolite (Meso-MFI and nanoporous Al-MCM-48 using pyrolysis gas chromatography/mass spectrometry (Py-GC/MS. The effect of the catalyst type on the product distribution and chemical composition of the bio-oil was examined using Py-GC/MS. The Meso-MFI exhibited a higher activity in deoxygenation and aromatization during the catalytic pyrolysis of L. japonica. Meanwhile, the catalytic activity of Al-MCM-48 was lower than that of Meso-MFI due to its weak acidity.

  15. PYROLYSIS OF WOODY MATERIAL

    Directory of Open Access Journals (Sweden)

    Martin Bajus

    2010-09-01

    Full Text Available This work aimed to study the recovery of beech wood by the process of pyrolysis. The effects ofexperimental conditions in products yield and composition were studied. The thermal behaviour offorestry biomass was studied in a batch reactor at temperatures ranging from 350oC to 450oC. Thereaction time of wood thermal degradation took 95 min. The main objective was the identificationof the oxygenates and carbonaceous species generated by pyrolysis of beech wood. The productsof wood cracking were classified into three groups : 25.1 %wt. of gas, 44.3 %wt. of liquids and30.6 %wt. of carbon solid residues. There is considerable experimental evidence that suggests thatthere is competition between gas, liquids and char during wood pyrolysis which depends on theheating conditions.

  16. Low temperature growth of highly crystallized ZnO:Al films by ultrasonic spray pyrolysis from acetylacetone salt

    International Nuclear Information System (INIS)

    High-quality ZnO:Al films were deposited on glass substrates at a relatively low temperature of 300 deg. C by ultrasonic spray pyrolysis. Zn(acac)2 and Al(acac)3 acted as zinc and aluminum source, which dissolved in ethanol-water solution. The influences of aluminum concentration and vacuum annealing on microstructure, electrical and optical properties were investigated by XRD, SEM, EDS, four-point probe and visible spectroscopy. The experimental results shown that ZnO:Al films exhibit stronger (1 0 1) preferred orientation and have lenticular-like grain morphology. The resistivity as low as 4.3 x 10-1 ? cm for as-deposited films was obtained at the 4 at.% doping concentration, which can be decreased to 10-2 ? cm level by post-deposited vacuum annealing. The average transmittance of as-deposited films was nearly 80% in the visible range, and that of 4 at.% doped ZnO films reduced to 60% after vacuum annealing at 550-600 deg. C.

  17. Low temperature growth of highly crystallized ZnO:Al films by ultrasonic spray pyrolysis from acetylacetone salt

    Energy Technology Data Exchange (ETDEWEB)

    Xu Jiwen, E-mail: csuxjw@126.co [School of Material Science and Engineering, Guilin University of Electronic Technology, No. 1 Jinji Road, Guilin 541004, Guangxi (China); Wang Hua [School of Material Science and Engineering, Guilin University of Electronic Technology, No. 1 Jinji Road, Guilin 541004, Guangxi (China); Guangxi Key Laboratory of Information Materials, Guilin University of Electronic Technology, Guilin 541004 (China); Yang Ling; Jiang Minghong; Wei Shuai; Zhang Tingting [School of Material Science and Engineering, Guilin University of Electronic Technology, No. 1 Jinji Road, Guilin 541004, Guangxi (China)

    2010-03-25

    High-quality ZnO:Al films were deposited on glass substrates at a relatively low temperature of 300 deg. C by ultrasonic spray pyrolysis. Zn(acac){sub 2} and Al(acac){sub 3} acted as zinc and aluminum source, which dissolved in ethanol-water solution. The influences of aluminum concentration and vacuum annealing on microstructure, electrical and optical properties were investigated by XRD, SEM, EDS, four-point probe and visible spectroscopy. The experimental results shown that ZnO:Al films exhibit stronger (1 0 1) preferred orientation and have lenticular-like grain morphology. The resistivity as low as 4.3 x 10{sup -1} OMEGA cm for as-deposited films was obtained at the 4 at.% doping concentration, which can be decreased to 10{sup -2} OMEGA cm level by post-deposited vacuum annealing. The average transmittance of as-deposited films was nearly 80% in the visible range, and that of 4 at.% doped ZnO films reduced to 60% after vacuum annealing at 550-600 deg. C.

  18. Do molecular assemblages released at progressive pyrolysis temperatures reflect different organizational levels in the structure of soil humic acid?

    OpenAIRE

    Almendros, G.; Hernández, Zulimar; González-Pérez, José Antonio; Cuadra, L; Fernández, E

    2008-01-01

    Analytical pyrolysis is a classical tool for the structural research of humic substances, invoked as a technique superior to wet chemical degradation because its outstanding potential for the breakdown of the C¿C bonds even in the most recalcitrant structural domains. Also, it enables the release of a large variety of products in a wide range of polarity and derived from lipid, carbohydrate, lignin or protein. Nevertheless, the potential of analytical pyrolysis for unbiased structural analys...

  19. Flash pyrolysis at high temperature of ligno-cellulosic biomass and its components - production of synthesis gas; Pyrolyse flash a haute temperature de la biomasse ligno-cellulosique et de ses composes - production de gaz de synthese

    Energy Technology Data Exchange (ETDEWEB)

    Couhert, C

    2007-11-15

    Pyrolysis is the first stage of any thermal treatment of biomass and governs the formation of synthesis gas for the production of electricity, hydrogen or liquid fuels. The objective of this work is to establish a link between the composition of a biomass and its pyrolysis gas. We study experimental flash pyrolysis and fix the conditions in which quantities of gas are maximal, while aiming at a regime without heat and mass transfer limitations (particles about 100 {mu}m): temperature of 950 C and residence time of about 2 s. Then we try to predict gas yields of any biomass according to its composition, applicable in this situation where thermodynamic equilibrium is not reached. We show that an additivity law does not allow correlating gas yields of a biomass with fractions of cellulose, hemi-cellulose and lignin contained in this biomass. Several explanations are suggested and examined: difference of pyrolytic behaviour of the same compound according to the biomass from which it is extracted, interactions between compounds and influence of mineral matter. With the aim of industrial application, we study pyrolysis of millimetric and centimetric size particles, and make a numerical simulation of the reactions of pyrolysis gases reforming. This simulation shows that the choice of biomass affects the quantities of synthesis gas obtained. (author)

  20. Characterization of the pyrolysis oil produced in the slow pyrolysis of sunflower-extracted bagasse

    Energy Technology Data Exchange (ETDEWEB)

    Yorgun, S.; Sensoz, S. [Osmangazi Univ., Eskisehir (Turkey). Dept. of Chemical Engineering; Kockar, O.M. [Anadolu Univ., Eskisehir (Turkey). Dept. of Chemical Engineering

    2001-07-01

    Sunflower (Helianthus annus L.)-extracted bagasse pyrolysis experiments were performed in a fixed-bed reactor. The effects of heating rate, final pyrolysis temperature, particle size and pyrolysis atmosphere on the pyrolysis product yields and chemical compositions have been investigated. The maximum oil yield of 23% was obtained in N{sub 2} atmosphere at a pyrolysis temperature of 550 {sup o}C and a heating rate of 7 {sup o}C min {sup -1}. The chemical characterisation has shown that the oil obtained from sunflower-extracted bagasse may be potentially valuable as fuel and chemical feedstocks. (Author)

  1. Catalytic pyrolysis using UZM-44 aluminosilicate zeolite

    Energy Technology Data Exchange (ETDEWEB)

    Nicholas, Christopher P; Boldingh, Edwin P

    2014-04-29

    A new family of aluminosilicate zeolites designated UZM-44 has been synthesized. These zeolites are represented by the empirical formula. Na.sub.nM.sub.m.sup.k+T.sub.tAl.sub.1-xE.sub.xSi.sub.yO.sub.z where "n" is the mole ratio of Na to (Al+E), M represents a metal or metals from zinc, Group 1, Group 2, Group 3 and or the lanthanide series of the periodic table, "m" is the mole ratio of M to (Al+E), "k" is the average charge of the metal or metals M, T is the organic structure directing agent or agents, and E is a framework element such as gallium. The process involves contacting a carbonaceous biomass feedstock with UZM-44 at pyrolysis conditions to produce pyrolysis gases comprising hydrocarbons. The catalyst catalyzes a deoxygenation reaction converting oxygenated hydrocarbons into hydrocarbons and removing the oxygen as carbon oxides and water. A portion of the pyrolysis gases is condensed to produce low oxygen biomass-derived pyrolysis oil.

  2. Catalytic pyrolysis using UZM-44 aluminosilicate zeolite

    Energy Technology Data Exchange (ETDEWEB)

    Nicholas, Christopher P; Boldingh, Edwin P

    2013-12-17

    A new family of aluminosilicate zeolites designated UZM-44 has been synthesized. These zeolites are represented by the empirical formula Na.sub.nM.sub.m.sup.k+T.sub.tAl.sub.1-xE.sub.xSi.sub.yO.sub.z where "n" is the mole ratio of Na to (Al+E), M represents a metal or metals from zinc, Group 1, Group 2, Group 3 and or the lanthanide series of the periodic table, "m" is the mole ratio of M to (Al+E), "k" is the average charge of the metal or metals M, T is the organic structure directing agent or agents, and E is a framework element such as gallium. The process involves contacting a carbonaceous biomass feedstock with UZM-44 at pyrolysis conditions to produce pyrolysis gases comprising hydrocarbons. The catalyst catalyzes a deoxygenation reaction converting oxygenated hydrocarbons into hydrocarbons and removing the oxygen as carbon oxides and water. A portion of the pyrolysis gases is condensed to produce low oxygen biomass-derived pyrolysis oil.

  3. Catalytic Pyrolysis of Cotton Straw by Zeolites and Metal Oxides

    Science.gov (United States)

    Cao, X. X.; Shen, B. X.; Lu, F.; Yao, Y.

    The influences of zeolites and metal oxides on the pyrolysis of cotton straw have been studied by thermogravimetric analysis (TGA). And performance of different catalysts to volatile and yield of ash was compared. The results showed that the catalytic pyrolysis experienced three stages: water losing stage, activated pyrolysis stage(APS), passive pyrolysis stage(pPS). The passive pyrolysis stage for pure cotton straw was small. The addition of the catalysts decreased the percent of volatile conversion for activated pyrolysis stage, but with the decreasing temperature for passive pyrolysis stage and increasing the percent of volatile conversion for passive pyrolysis stage. These catalysts promoted the pyrolysis of lignin, but showed less performance to the pyrolysis of cellulose and hemicellulose. The yield of ash increased in the presence of catalysts,and the yield was higher when catalyzed by metal oxide than by zeolite.

  4. Temperature-dependent benzoic acid elimination mechanisms in pyrolysis of (-)-cocaine

    Scientific Electronic Library Online (English)

    Michal, Novák.

    Full Text Available The thermal elimination of benzoic acid from (-)-cocaine is shown to be temperature-dependent. In the temperature range of 200-500 °C only a trans-elimination is observed leading to methylecgonidine. Above ca. 500 °C a second mechanism, the cis-elimination, comes up yielding a novel alkaloid methyli [...] soecgonidine which has been characterized by means of mass spectrometry. At 600 °C the cis-elimination predominates. The trans-elimination is postulated a two-step process consisting of a 1,7- and a 1,5-hydrogen shift. The chemistry of cocaine base smoking is explained using the theory of chemical activation.

  5. Pyrolysis and oxidative pyrolysis experiments with organization exchange resin

    International Nuclear Information System (INIS)

    Pyrolysis may be an important pretreatment step before vitrification in a cold crucible melter (CCM). During vitrification of organic resin the carbon or other remaining residues may harm the performance of the cold crucible melter of the eventual stability of the final glass product. Hence, it is important to reduce or prevent such harmful waste from entry into the cold crucible melter. Pretreatment with pyrolysis will generally provide volume reduction resulting in less amount of solid waste that needs to be handled by the CCM; in addition, the pyrolytic processes may breakdown much of the complex organics causing release through volatilization resulting in less carbon and other harmful substances. Hence, KEPRI has undertaken studies on the pyrolysis and oxidative pyrolysis of organic ion exchange resin. Pyrolysis and oxidative pyrolysis were examined with TGA and a tube furnace. TGA results for pyrolysis with the flow of nitrogen indicate that even after pyrolyzing from room temperature to about 900 deg C, a significant mass fraction of the original cationic resin remains, approximately 46 %. The anionic resin when pyrolytically heated in a flow of nitrogen only, from room temperature to about 900 deg C, produced a final residue mass fraction of about 8 percent. Oxidation at a ratio of air to nitrogen, 1:2, reduced the cationic resin to 5.3% when heated at 5 C/min. Oxidation of anionic resin at the same ratio and same heating rate left almost no solid residue. Pyrolysis (e.g. nitrogen-only environment) in the tube furnace of larger samples relative to the TGA produced very similar results to the TGA. The differences may be attributed to the scale effects such as surface area exposure to the gas stream, temperature distributions throughout the resin, etc. (author) 7 refs., 7 figs

  6. Effect of the substrate temperature on the physical properties of molybdenum tri-oxide thin films obtained through the spray pyrolysis technique

    International Nuclear Information System (INIS)

    Polycrystalline molybdenum tri-oxide thin films were prepared using the spray pyrolysis technique; a 0.1 M solution of ammonium molybdate tetra-hydrated was used as a precursor. The samples were prepared on Corning glass substrates maintained at temperatures ranging between 423 and 673 K. The samples were characterized through micro Raman, X-ray diffraction, optical transmittance and DC electrical conductivity. The species MoO3 (H2O)2 was found in the sample prepared at a substrate temperature of 423 K. As the substrate temperature rises, the water disappears and the samples crystallize into ?-MoO3. The optical gap diminishes as the substrate temperature rises. Two electrical transport mechanisms were found: hopping under 200 K and intrinsic conduction over 200 K. The MoO3 films' sensitivity was analyzed for CO and H2O in the temperature range 160 to 360 K; the results indicate that CO and H2O have a reduction character. In all cases, it was found that the sensitivity to CO is lower than that to H2O. - Highlights: ? A low cost technique is used which produces good material. ? Thin films are prepared using ammonium molybdate tetra hydrated. ? The control of the physical properties of the samples could be done. ? A calculation method is proposed to determine the material optical properties. ? The MoO3 thin films prepared by spray pyrolysis could be used as gas syrolysis could be used as gas sensor.

  7. Effect of low-temperature oxidation on the pyrolysis and combustion of whole oil

    International Nuclear Information System (INIS)

    Low-temperature oxidation (LTO) of the Fosterton crude oil mixed with its reservoir sand has been investigated in a tubular reactor. Reservoir sand saturated with 15 wt% of crude oil (20.5o API gravity) was subjected to air injection at low-temperature (220 oC) for a period of time (17 h and 30 min), resulting in the formation of an oxygenated hydrocarbon fuel. The vent gases were analyzed for the content of CO, CO2, and oxygen and the residue was analyzed to determine the elemental composition and calorific value. The presence of LTO region was verified from the values of apparent H/C ratio. In addition, thermal behavior and combustion kinetics of the residue was investigated using thermogravimetric analysis (TGA). TG involves both non-isothermal and isothermal analysis and kinetic data was derived from isothermal studies. The general model for nth order reaction was used to obtain the kinetic parameters of the coke oxidation reaction. The activation energy, frequency factor and order of the reactions were determined using the model.

  8. Catalytic pyrolysis of Laminaria japonica over nanoporous catalysts using Py-GC/MS

    OpenAIRE

    Jeon Jong-Ki; Jeong Kwang-Eun; Chae Ho-Jeong; Park Sung Hoon; Lee Hyung Won; Park Young-Kwon

    2011-01-01

    Abstract The catalytic pyrolysis of Laminaria japonica was carried out over a hierarchical meso-MFI zeolite (Meso-MFI) and nanoporous Al-MCM-48 using pyrolysis gas chromatography/mass spectrometry (Py-GC/MS). The effect of the catalyst type on the product distribution and chemical composition of the bio-oil was examined using Py-GC/MS. The Meso-MFI exhibited a higher activity in deoxygenation and aromatization during the catalytic pyrolysis of L. japonica. Meanwhile, the catalytic activity of...

  9. Pyrolysis of tyres. Influence of the final temperature of the process on emissions and the calorific value of the products recovered

    International Nuclear Information System (INIS)

    A study was made of the pyrolysis of tyre particles, with the aim of determining the possibilities of using the products resulting from the process as fuel. Three final temperatures were used, determined from thermogravimetric data. The design of the experiment was a horizontal oven containing a reactor into which particles of the original tyre were placed. After the process, a solid fraction (char) remained in the reactor, while the gases generated went through a set of scrubbers where most of the condensable fraction (oils) was retained. Finally, once free of this fraction, the gases were collected in glass ampoules. Solid and liquids fractions were subjected to thermogravimetric analyses in order to study their combustibility. The gas fraction was analysed by means of gas chromatography to establish the content of CO, CO2, H2 and hydrocarbons present in the samples (mainly components of gases produced in the pyrolysis process). A special study was made of the sulphur and chlorine content of all the fractions, as the presence of these elements could be problematic if the products are used as fuel. Tyre pyrolysis engenders a solid carbon residue that concentrates sulphur and chorine, with a relatively high calorific value, although not so high as that of the original tyre. The liquid fraction produced by the process has a high calorific value, which rises with the final temperature, up to 40 MJ/kg. The chlorine content of this fraction is neglighlorine content of this fraction is negligible. Over 95% of the gas fraction, regardless of the final temperature, is composed of hydrocarbons of a low molecular weight and hydrogen, this fraction also appearing to be free of chlorine

  10. Pyrolysis processing for solid waste resource recovery

    Science.gov (United States)

    Serio, Michael A. (Inventor); Kroo, Erik (Inventor); Wojtowicz, Marek A. (Inventor); Suuberg, Eric M. (Inventor)

    2007-01-01

    Solid waste resource recovery in space is effected by pyrolysis processing, to produce light gases as the main products (CH.sub.4, H.sub.2, CO.sub.2, CO, H.sub.2O, NH.sub.3) and a reactive carbon-rich char as the main byproduct. Significant amounts of liquid products are formed under less severe pyrolysis conditions, and are cracked almost completely to gases as the temperature is raised. A primary pyrolysis model for the composite mixture is based on an existing model for whole biomass materials, and an artificial neural network models the changes in gas composition with the severity of pyrolysis conditions.

  11. Pyrolysis process for producing fuel gas

    Science.gov (United States)

    Serio, Michael A. (Inventor); Kroo, Erik (Inventor); Wojtowicz, Marek A. (Inventor); Suuberg, Eric M. (Inventor)

    2007-01-01

    Solid waste resource recovery in space is effected by pyrolysis processing, to produce light gases as the main products (CH.sub.4, H.sub.2, CO.sub.2, CO, H.sub.2O, NH.sub.3) and a reactive carbon-rich char as the main byproduct. Significant amounts of liquid products are formed under less severe pyrolysis conditions, and are cracked almost completely to gases as the temperature is raised. A primary pyrolysis model for the composite mixture is based on an existing model for whole biomass materials, and an artificial neural network models the changes in gas composition with the severity of pyrolysis conditions.

  12. Structural and optical properties of nanostructural V{sub 2}O{sub 5} thin films deposited by spray pyrolysis technique: Effect of the substrate temperature

    Energy Technology Data Exchange (ETDEWEB)

    Irani, R. [Spray Lab, Physics Department, University of Guilan, Rasht (Iran, Islamic Republic of); Rozati, S.M., E-mail: smrozati@gmail.com [Spray Lab, Physics Department, University of Guilan, Rasht (Iran, Islamic Republic of); Beke, S. [Department of Nanophysics, Istituto Italiano di Tecnologia (IIT), via Morego 30, 16163 Genova (Italy)

    2013-05-15

    V{sub 2}O{sub 5} thin films were deposited on glass substrates by spray pyrolysis technique. The variation in the structural and optical properties with a variation in the substrate temperature was investigated by means of X-ray diffraction (XRD) and UV–vis spectrophotometer. XRD was used to reveal the possible orientations of crystallites in the films prepared at different substrate temperatures ranging from 200 °C to 550 °C. The results showed that by increasing the temperature, the films grew along the (001) direction with an orthorhombic structure. The crystallite size was calculated using the Scherrer equation and observed that it increased with elevating the substrate temperature to 450 °C, but decreased when further increasing it. The highest transmittance was achieved when films were deposited at 550 °C. The absorption edge was estimated by using the Tauc plot. In the range 350 °C–550 °C, a shift of the absorption edge from 2.5 eV to 2.8 eV was observed due to the formation of chemical bonds at the V{sub 2}O{sub 5} film–substrate interface at high substrate temperatures (>450 °C). Field emission scanning electron microscopy showed that nanorods were formed when depositing at 500 °C. We conclude that by altering the substrate temperature the size of crystallites can be well controlled. - Highlights: ? Spray pyrolysis technique was used. ? We have synthesized highly oriented nanocrystalline V{sub 2}O{sub 5} films. ? By altering the substrate temperature the size of crystallites can be well controlled. ? The highest transmittance was achieved when films were deposited at 550 °C. ? Scanning electron microscopy showed that nanorods were formed when depositing at 500 °C.

  13. Structural and optical properties of nanostructural V2O5 thin films deposited by spray pyrolysis technique: Effect of the substrate temperature

    International Nuclear Information System (INIS)

    V2O5 thin films were deposited on glass substrates by spray pyrolysis technique. The variation in the structural and optical properties with a variation in the substrate temperature was investigated by means of X-ray diffraction (XRD) and UV–vis spectrophotometer. XRD was used to reveal the possible orientations of crystallites in the films prepared at different substrate temperatures ranging from 200 °C to 550 °C. The results showed that by increasing the temperature, the films grew along the (001) direction with an orthorhombic structure. The crystallite size was calculated using the Scherrer equation and observed that it increased with elevating the substrate temperature to 450 °C, but decreased when further increasing it. The highest transmittance was achieved when films were deposited at 550 °C. The absorption edge was estimated by using the Tauc plot. In the range 350 °C–550 °C, a shift of the absorption edge from 2.5 eV to 2.8 eV was observed due to the formation of chemical bonds at the V2O5 film–substrate interface at high substrate temperatures (>450 °C). Field emission scanning electron microscopy showed that nanorods were formed when depositing at 500 °C. We conclude that by altering the substrate temperature the size of crystallites can be well controlled. - Highlights: ? Spray pyrolysis technique was used. ? We have synthesized highly oriented nanocrystalline V2O5 films. ? By altering the substrate temperature the size of crystallites can be well controlled. ? The highest transmittance was achieved when films were deposited at 550 °C. ? Scanning electron microscopy showed that nanorods were formed when depositing at 500 °C

  14. Controlled air pyrolysis incinerator

    International Nuclear Information System (INIS)

    An advanced controlled air pyrolysis incinerator has been researched, developed and placed into commercial operation for both radioactive and other combustible wastes. Engineering efforts cocentrated on providing an incinerator which emitted a clean, easily treatable off-gas and which produced a minimum amount of secondary waste. Feed material is continuously fed by gravity into the system's pyrolysis chamber without sorting, shredding, or other such pretreatment. Metal objects, liquids such as oil and gasoline, or solid products such as resins, blocks of plastic, tire, animal carcasses, or compacted trash may be included along with normal processed waste. The temperature of the waste is very gradually increased in a reduced oxygen atmosphere. Volatile pyrolysis gases are produced, tar-like substances are cracked and the resulting product, a relatively uniform, easily burnable material, is introduced into the combustion chamber. Steady burning is thus accomplished under easily controlled excess air conditions with the off-gasthen passing through a simple dry clean-up system. Gas temperatures are then reduced by air dilution before passing through final HEPA filters. Both commercial and nuclear installations have been operated with the most recent application being the central incinerator to service West Germany's nuclear reactors

  15. Influence of pyrolysis temperature on fracture response in SiOC based composites reinforced by basalt woven fabric.

    Czech Academy of Sciences Publication Activity Database

    Chlup, Zden?k; ?erný, Martin; Strachota, Adam; Sucharda, Zbyn?k; Halasová, Martina; Dlouhý, Ivo

    2014-01-01

    Ro?. 34, ?. 14 (2014), s. 3389-3398. ISSN 0955-2219 R&D Projects: GA ?R GAP107/12/2445; GA MŠk(CZ) ED1.1.00/02.0068 Institutional support: RVO:68081723 ; RVO:67985891 ; RVO:61389013 Keywords : Fracture behaviour * CMCs * Pyrolysis * Basalt fibre * Polysiloxane Subject RIV: JL - Materials Fatigue, Friction Mechanics; JI - Composite Materials (USMH-B); JH - Ceramics, Fire-Resistant Materials and Glass (UMCH-V) Impact factor: 2.307, year: 2013

  16. Biomass pyrolysis and combustion integral and differential reaction heats with temperatures using thermogravimetric analysis/differential scanning calorimetry.

    Science.gov (United States)

    Shen, Jiacheng; Igathinathane, C; Yu, Manlu; Pothula, Anand Kumar

    2015-06-01

    Integral reaction heats of switchgrass, big bluestem, and corn stalks were determined using thermogravimetric analysis/differential scanning calorimetry (TGA/DSC). Iso-conversion differential reaction heats using TGA/DSC pyrolysis and combustion of biomass were not available, despite reports available on heats required and released. A concept of iso-conversion differential reaction heats was used to determine the differential reaction heats of each thermal characteristics segment of these materials. Results showed that the integral reaction heats were endothermic from 30 to 700°C for pyrolysis of switchgrass and big bluestem, but they were exothermic for corn stalks prior to 587°C. However, the integral reaction heats for combustion of the materials followed an endothermic to exothermic transition. The differential reaction heats of switchgrass pyrolysis were predominantly endothermic in the fraction of mass loss (0.0536-0.975), and were exothermic for corn stalks (0.0885-0.850) and big bluestem (0.736-0.919). Study results provided better insight into biomass thermal mechanism. PMID:25756207

  17. A two-dimensional hybrid with molybdenum disulfide nanocrystals strongly coupled on nitrogen-enriched graphene via mild temperature pyrolysis for high performance lithium storage

    Science.gov (United States)

    Tang, Yanping; Wu, Dongqing; Mai, Yiyong; Pan, Hao; Cao, Jing; Yang, Chongqing; Zhang, Fan; Feng, Xinliang

    2014-11-01

    A novel 2D hybrid with MoS2 nanocrystals strongly coupled on nitrogen-enriched graphene (MoS2/NGg-C3N4) is realized by mild temperature pyrolysis (550 °C) of a self-assembled precursor (MoS3/g-C3N4-H+/GO). With rich active sites, the boosted electronic conductivity and the coupled structure, MoS2/NGg-C3N4 achieves superior lithium storage performance.A novel 2D hybrid with MoS2 nanocrystals strongly coupled on nitrogen-enriched graphene (MoS2/NGg-C3N4) is realized by mild temperature pyrolysis (550 °C) of a self-assembled precursor (MoS3/g-C3N4-H+/GO). With rich active sites, the boosted electronic conductivity and the coupled structure, MoS2/NGg-C3N4 achieves superior lithium storage performance. Electronic supplementary information (ESI) available: Photo images, Zeta potential, additional SEM, TEM, HRTEM and AFM images, XRD, FTIR, TGA under N2, TGA under air, pore size distribution, additional XPS are presented. N doping conditions, cycling/rate performances are listed in tables. See DOI: 10.1039/c4nr05519e

  18. Toxicity of pyrolysis gases from polyether sulfone

    Science.gov (United States)

    Hilado, C. J.; Olcomendy, E. M.

    1979-01-01

    A sample of polyether sulfone was evaluated for toxicity of pyrolysis gases, using the toxicity screening test method developed at the University of San Francisco. Animal response times were relatively short at pyrolysis temperatures of 600 to 800 C, with death occurring within 6 min. The principal toxicant appeared to be a compound other than carbon monoxide.

  19. Characteristics of liquid product from the pyrolysis of waste plastic mixture at low and high temperatures: Influence of lapse time of reaction

    International Nuclear Information System (INIS)

    Pyrolysis of a waste plastic mixture (high-density polyethylene: low-density polyethylene: polypropylene: polystyrene = 3:2:3:1) into a liquid product was carried out in a stirred semi-batch reactor at low (350 deg. C) and high (400 deg. C) temperatures. The effect of lapse time of reaction in the reactor and also degradation temperature on the characteristics of the liquid product from pyrolysis of the mixture was investigated. Liquid products were described by cumulative amount distribution, paraffin, olefin, naphthene and aromatic (PONA) distribution and molecular weight distribution. Their characteristic was quite differed with a lapse time of reaction and also at a low and high degradation temperatures, because of the different physicochemical properties of the plastic types in the mixture. With increase of lapse time of reaction, the order for the main products in PONA components obtained at 350 deg. C was firstly aromatic products and then olefin products, while at 400 deg. C the order was firstly aromatic products, then olefin products and finally paraffin products. The experiments also showed from the molecular weight distribution of liquid PONA components that the paraffin and olefin products had a wide distribution by mainly random scission of polymer, but in the case of olefin products were produced by an end-chain scission mechanism as well as random scission mechanism, as evidenced by much more light olefin products. This phenomenon was evident at a highcts. This phenomenon was evident at a higher degradation temperature. Also, both the light olefin and naphthene products with a molecular weight of around 120, as a main product, showed a similar trend as a function of lapse time, which had a maximum fraction at 343 min (at 350 deg. C) and 83 min (at 400 deg. C). Among PONA components, the highest concentrations of aromatic products were obtained with a molecular weight of around 100 at the fastest lapse time of reaction, regardless of degradation temperature. It was concluded that the characteristics of liquid product on the pyrolysis of plastic mixtures were strongly influenced by lapse time of reaction and degradation temperature

  20. Structural and photoluminescence characterization of SnO2: F thin films deposited by advanced spray pyrolysis technique at low substrate temperature

    International Nuclear Information System (INIS)

    Fluorine doped tin oxide (FTO) thin films were deposited on glass substrates, at different substrate temperatures using advanced spray pyrolysis technique. X-ray diffraction studies showed that the crystallinity of the thin films increased with increasing substrate temperature. FESEM and AFM studies support the conclusions drawn from X-ray diffraction studies. X-ray photoelectron studies confirm oxygen deficiency in formation of the FTO nanocrystallites. The photoluminescence of the FTO films were investigated. It was found that, room temperature photoluminescence spectra are dominated by oxygen vacancies and exhibit a rich violet photoluminescence band about ?404 nm with an extensively feeble red emission about 700 nm. The Photoluminescence intensity varies with the substrate temperature. The photoemission position is observed to be independent of substrate temperature. -- Highlights: ? Photoluminescent FTO thin films were deposited at low substrate temperatures. ? Influence of substrate temperature on the PL characteristics was studied. ? The samples are polycrystalline with a cassiterite tetragonal crystal structure. ? The room temperature UV/violet PL emission was dominated by the oxygen vacancies. ? PL efficiency is optimum at 613 K substrate temperature

  1. Structural and photoluminescence characterization of SnO{sub 2}: F thin films deposited by advanced spray pyrolysis technique at low substrate temperature

    Energy Technology Data Exchange (ETDEWEB)

    Shewale, P.S. [Thin Film Physics Laboratory, Department of Electronics, Shivaji University, Kolhapur 416004 (India); Ung Sim, Kyu; Kim, Ye-bin; Kim, J.H. [Department of Materials Science and Engineering, Chonnam National University, 300 Yongbong-Dong, Buk-Gu, Gwangju 500757 (Korea, Republic of); Moholkar, A.V. [Department of Physics, Shivaji University, Kolhapur 416004 (India); Uplane, M.D., E-mail: mdu_eln@unishivaji.ac.in [Thin Film Physics Laboratory, Department of Electronics, Shivaji University, Kolhapur 416004 (India)

    2013-07-15

    Fluorine doped tin oxide (FTO) thin films were deposited on glass substrates, at different substrate temperatures using advanced spray pyrolysis technique. X-ray diffraction studies showed that the crystallinity of the thin films increased with increasing substrate temperature. FESEM and AFM studies support the conclusions drawn from X-ray diffraction studies. X-ray photoelectron studies confirm oxygen deficiency in formation of the FTO nanocrystallites. The photoluminescence of the FTO films were investigated. It was found that, room temperature photoluminescence spectra are dominated by oxygen vacancies and exhibit a rich violet photoluminescence band about ?404 nm with an extensively feeble red emission about 700 nm. The Photoluminescence intensity varies with the substrate temperature. The photoemission position is observed to be independent of substrate temperature. -- Highlights: ? Photoluminescent FTO thin films were deposited at low substrate temperatures. ? Influence of substrate temperature on the PL characteristics was studied. ? The samples are polycrystalline with a cassiterite tetragonal crystal structure. ? The room temperature UV/violet PL emission was dominated by the oxygen vacancies. ? PL efficiency is optimum at 613 K substrate temperature.

  2. Effect of temperature on structural, optical and photoluminescence properties of polycrystalline CuInS2 thin films prepared by spray pyrolysis

    International Nuclear Information System (INIS)

    Copper indium disulphide (CuInS2), is a good absorber material for photovoltaic applications. In this work, CuInS2 is deposited by chemical spray pyrolysis on heated glass substrates. It is observed that the film growth temperature and the ion ratio Cu/In affects the structural and optical properties of CuInS2 thin films. This paper presents the effect of temperature on the growth (for the ion ratio Cu/In=1.25), optical and photoluminescence properties of sprayed CuInS2 films. The XRD patterns confirm the well defined single phase composition of CuInS2 films grown from 300 to 350 deg. C (at Cu/In=1.25) as optimum temperature for depositing well defined crystallites along (1 1 2) oriented CuInS2 thin films with chalcopyrite structure. D2d point symmetry group is associated with the CuInS2 crystallites with energy gap of 1.53 eV at room temperature. The chemical nature and the presence of additional phases are discussed based on the EDAX measurements. The absorption coefficient of sprayed CuInS2 films is found to be in the order of 105-106 cm-1 in the UV-visible region and the optical band gap decreases with increase in temperature. Defects-related photoluminescence properties are also discussed. CuInS2 polycrystalline films are prepared by the cost effective method of spray pyrolysis from the aqueous solutions of copper (II) chlm the aqueous solutions of copper (II) chloride, indium (III) chloride and thiourea for synthesis on heated glass substrates.

  3. Effect of the substrate temperature on the physical properties of molybdenum tri-oxide thin films obtained through the spray pyrolysis technique

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, H.M. [Grupo de Materiales con Aplicaciones Tecnologicas, Departamento de Fisica Universidad Nacional de Colombia sede Bogota (Colombia); Torres, J., E-mail: njtorress@unal.edu.co [Grupo de Materiales con Aplicaciones Tecnologicas, Departamento de Fisica Universidad Nacional de Colombia sede Bogota (Colombia); Lopez Carreno, L.D. [Grupo de Materiales con Aplicaciones Tecnologicas, Departamento de Fisica Universidad Nacional de Colombia sede Bogota (Colombia); Rodriguez-Garcia, M.E. [Departamento de Nanotecnologia, Centro de Fisica Aplicada y Tecnologia Avanzada, Universidad Nacional Autonoma de Mexico, Campus Juriquilla, Queretaro, Qro., Mexico (Colombia)

    2013-01-15

    Polycrystalline molybdenum tri-oxide thin films were prepared using the spray pyrolysis technique; a 0.1 M solution of ammonium molybdate tetra-hydrated was used as a precursor. The samples were prepared on Corning glass substrates maintained at temperatures ranging between 423 and 673 K. The samples were characterized through micro Raman, X-ray diffraction, optical transmittance and DC electrical conductivity. The species MoO{sub 3} (H{sub 2}O){sub 2} was found in the sample prepared at a substrate temperature of 423 K. As the substrate temperature rises, the water disappears and the samples crystallize into {alpha}-MoO{sub 3}. The optical gap diminishes as the substrate temperature rises. Two electrical transport mechanisms were found: hopping under 200 K and intrinsic conduction over 200 K. The MoO{sub 3} films' sensitivity was analyzed for CO and H{sub 2}O in the temperature range 160 to 360 K; the results indicate that CO and H{sub 2}O have a reduction character. In all cases, it was found that the sensitivity to CO is lower than that to H{sub 2}O. - Highlights: Black-Right-Pointing-Pointer A low cost technique is used which produces good material. Black-Right-Pointing-Pointer Thin films are prepared using ammonium molybdate tetra hydrated. Black-Right-Pointing-Pointer The control of the physical properties of the samples could be done. Black-Right-Pointing-Pointer A calculation method is proposed to determine the material optical properties. Black-Right-Pointing-Pointer The MoO{sub 3} thin films prepared by spray pyrolysis could be used as gas sensor.

  4. Time resolved pyrolysis of char

    DEFF Research Database (Denmark)

    Egsgaard, Helge; Ahrenfeldt, Jesper

    In laboratory experiments, biomass char was produced under controlled conditions using wood chips from French pinewood. Different char qualities were obtained by pyrolysing the biomass at similar heating rates with end-temperatures ranging from 250 to 1000 o C. The char was analysed by flash pyrolysis, and slow heating in direct combination with mass spectrometry, gas chromatography/mass spectrometry and flame ionization detection, respectively. Characteristic ions derived from the flash pyrolysis-gas chromatography/mass spectrometry data enable the release of volatiles to be time and, hence, temperature resolved.

  5. PYROLYSIS OF TOBACCO RESIDUE: PART 1. THERMAL

    OpenAIRE

    Mehmet K. Akalin; Selhan Karagöz

    2011-01-01

    The pyrolysis of two types of tobacco residue was carried out at different pyrolysis temperatures between 300 and 600 °C and a residence time of 1 h in a nitrogen atmosphere. The effect of pyrolysis temperature on the product distributions was investigated and the composition of the bio-oils identified. The variation in product distribution depended on both the temperature and the type of tobacco residues. The maximum liquid yields were obtained at 400°C for one sample and at 500°C for the ot...

  6. PYROLYSIS OF TOBACCO RESIDUE. PART 2: CATALYTIC

    OpenAIRE

    Mehmet K. Akalin; Selhan Karagöz

    2011-01-01

    The pyrolysis of tobacco residue in the presence of metal oxides and metal chlorides was investigated at 300, 400, and 500 °C. Catalysts used were Al2O3, Fe2O3, AlCl3, and SnCl4 in concentrations from 1 up to 5 wt% of the tobacco residue feedstock. The amount of catalysts and the pyrolysis temperature had significant effect on both product distributions and bio-oil composition. The catalytic effect was dominant at the lowest temperature (300 °C). The pyrolysis temperature was decreased by 200...

  7. Direct Synthesis of Fe3C-Functionalized Graphene by High Temperature Autoclave Pyrolysis for Oxygen Reduction

    DEFF Research Database (Denmark)

    Hu, Yang; Jensen, Jens Oluf

    2014-01-01

    We present a novel approach to direct fabrication of few-layer graphene sheets with encapsulated Fe3C nanoparticles from pyrolysis of volatile non-graphitic precursors without any substrate. This one-step autoclave approach is facile and potentially scalable for production. Tested as an electrocatalyst, the graphene-based composite exhibited excellent catalytic activity towards the oxygen reduction reaction in alkaline solution with an onset potential of ca. 1.05 V (vs. the reversible hydrogen electrode) and a half-wave potential of 0.83 V, which is comparable to the commercial Pt/C catalyst.

  8. Hypoxia exaggerates inspiratory accessory muscle deoxygenation during hyperpnoea.

    Science.gov (United States)

    Katayama, Keisho; Suzuki, Yasuhiro; Hoshikawa, Masako; Ohya, Toshiyuki; Oriishi, Marie; Itoh, Yuka; Ishida, Koji

    2015-06-01

    The purpose of this study was to elucidate inspiratory accessory muscle deoxygenation and myoelectric activity during isolated volitional hyperpnoea under hypoxic conditions. Subjects performed voluntary isocapnic hyperpnoea (tidal volume=30-40% of forced vital capacity, breathing frequency=60breaths/min) in normoxia [inspired gas fraction ( [Formula: see text] )=0.21] and hypoxia ( [Formula: see text] ). Muscle deoxyhemoglobin/myoglobin (Deoxy-Hb/Mb) and muscle oxygen saturation ( [Formula: see text] ) using near-infrared spectroscopy and surface electromyography were measured from sternocleidomastoid (SCM) and intercostal (IC) muscles. During hyperpnoea, increases in Deoxy-Hb/Mb and reductions of [Formula: see text] in the SCM and IC muscles were larger (Phypoxia than those in normoxia. Under hypoxic conditions, the electromyogram increases from the SCM and IC muscles during hyperpnoea were greater than that under the normoxic conditions. These results suggest that inspiratory accessory muscle deoxygenation during isolated hyperpnoea is exaggerated in hypoxia compared with normoxia and that hypoxia has a significant impact on inspiratory accessory muscle activation. PMID:25747385

  9. Pyrolysis of fast-growing aquatic biomass -Lemna minor (duckweed): Characterization of pyrolysis products.

    Science.gov (United States)

    Muradov, Nazim; Fidalgo, Beatriz; Gujar, Amit C; T-Raissi, Ali

    2010-11-01

    The aim of this work was to conduct the experimental study of pyrolysis of fast-growing aquatic biomass -Lemna minor (commonly known as duckweed) with the emphasis on the characterization of main products of pyrolysis. The yields of pyrolysis gas, pyrolytic oil (bio-oil) and char were determined as a function of pyrolysis temperature and the sweep gas (Ar) flow rate. Thermogravimetric/differential thermogravimetric (TG/DTG) analyses of duckweed samples in inert (helium gas) and oxidative (air) atmosphere revealed differences in the TG/DTG patterns obtained for duckweed and typical plant biomass. The bio-oil samples produced by duckweed pyrolysis at different reaction conditions were analyzed using GC-MS technique. It was found that pyrolysis temperature had minor effect on the bio-oil product slate, but exerted major influence on the relative quantities of the individual pyrolysis products obtained. While, the residence time of the pyrolysis vapors had negligible effect on the yield and composition of the duckweed pyrolysis products. PMID:20598878

  10. High electron mobility thin-film transistors based on Ga{sub 2}O{sub 3} grown by atmospheric ultrasonic spray pyrolysis at low temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Stuart R., E-mail: s.thomas09@imperial.ac.uk, E-mail: thomas.anthopoulos@imperial.ac.uk; Lin, Yen-Hung; Faber, Hendrik; Anthopoulos, Thomas D., E-mail: s.thomas09@imperial.ac.uk, E-mail: thomas.anthopoulos@imperial.ac.uk [Department of Physics, Blackett Laboratory, Imperial College London, London SW7 2BW (United Kingdom); Adamopoulos, George [Department of Engineering, Engineering Building, Lancaster University, Bailrigg, Lancaster LA1 4YR (United Kingdom); Sygellou, Labrini [Institute of Chemical Engineering and High Temperature Processes (ICEHT), Foundation of Research and Technology Hellas (FORTH), Stadiou Strasse Platani, P.O. Box 1414, Patras GR-265 04 (Greece); Stratakis, Emmanuel [Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology-Hellas (FORTH), Heraklion 71003 (Greece); Materials Science and Technology Department, University, of Crete, Heraklion 71003 (Greece); Pliatsikas, Nikos; Patsalas, Panos A. [Laboratory of Applied Physics, Department of Physics, Aristotle University of Thessaloniki, Thessaloniki GR-54124 (Greece)

    2014-09-01

    We report on thin-film transistors based on Ga{sub 2}O{sub 3} films grown by ultrasonic spray pyrolysis in ambient atmosphere at 400–450?°C. The elemental, electronic, optical, morphological, structural, and electrical properties of the films and devices were investigated using a range of complementary characterisation techniques, whilst the effects of post deposition annealing at higher temperature (700?°C) were also investigated. Both as-grown and post-deposition annealed Ga{sub 2}O{sub 3} films are found to be slightly oxygen deficient, exceptionally smooth and exhibit a wide energy bandgap of ?4.9?eV. Transistors based on as-deposited Ga{sub 2}O{sub 3} films show n-type conductivity with the maximum electron mobility of ?2?cm{sup 2}/V s.

  11. High electron mobility thin-film transistors based on Ga2O3 grown by atmospheric ultrasonic spray pyrolysis at low temperatures

    International Nuclear Information System (INIS)

    We report on thin-film transistors based on Ga2O3 films grown by ultrasonic spray pyrolysis in ambient atmosphere at 400–450?°C. The elemental, electronic, optical, morphological, structural, and electrical properties of the films and devices were investigated using a range of complementary characterisation techniques, whilst the effects of post deposition annealing at higher temperature (700?°C) were also investigated. Both as-grown and post-deposition annealed Ga2O3 films are found to be slightly oxygen deficient, exceptionally smooth and exhibit a wide energy bandgap of ?4.9?eV. Transistors based on as-deposited Ga2O3 films show n-type conductivity with the maximum electron mobility of ?2?cm2/V s.

  12. Potential method for gas production: high temperature co-pyrolysis of lignite and sewage sludge with vacuum reactor and long contact time.

    Science.gov (United States)

    Yang, Xiao; Yuan, Chengyong; Xu, Jiao; Zhang, Weijiang

    2015-03-01

    Lignite and sewage sludge were co-pyrolyzed in a vacuum reactor with high temperature (900°C) and long contact time (more than 2h). Beneficial synergetic effect on gas yield was clearly observed. Gas yield of blend fuel was evidently higher than that of both parent fuels. The gas volume yield, gas lower heating value (LHV), fixed carbon conversion and H2/CO ratio were 1.42 Nm(3)/kg(blend fuel), 10.57 MJ/Nm(3), 96.64% and 0.88% respectively, which indicated this new method a feasible one for gas production. It was possible that sewage sludge acted as gasification agents (CO2 and H2O) and catalyst (alkali and alkaline earth metals) provider during co-pyrolysis, promoting CO2-char and H2O-char gasification which, as a result, invited the improvement of gas volume yield, gas lower heating value and fixed carbon conversion. PMID:25542402

  13. Modeling CFB biomass pyrolysis reactors

    International Nuclear Information System (INIS)

    Fluidized bed-fast pyrolysis of biomass is considered as having a high commercial potential for the thermal treatment of biomass. This paper mainly presents a model developed further to improvements in the understanding of the science, and capable of predicting pyrolysis yields that are in satisfactory agreement with literature data. The kinetics and endothermicity of biomass pyrolysis are reviewed from extensive TGA and differential scanning calorimetry experiments. For most biomass species, the reaction rate constant is >0.5 s-1, corresponding to a fast reaction, so the requirement of a short reaction time for a high conversion can be met. Lab-scale batch experiments and pilot-scale CFB experiments show that an oil yield between 60 and 70 wt% can be achieved at an operating temperature of 510±10 oC, in line with literature data. Pyrolysis fundamentals are the basis of the developed model, applied to predict the yields of the different products as functions of process operation variables. The predictions are in fair agreement with our own conversion experiments and literature data. Finally, all findings are used and are illustrated in the design strategy of a CFB for the pyrolysis of biomass

  14. An Earth-system perspective on ocean deoxygenation during the end-Permian mass extinction

    Science.gov (United States)

    Cui, Y.

    2014-12-01

    Global ocean anoxia has been proposed to be the cause of the end-Permian (252 Ma) marine extinction event. Evidence for global-scale anoxia mainly comes from the study of organic geochemistry, framboidal pyrite, and redox-sensitive elements, although disagreement exists with respect to the interpretation of the observed patterns. Climate models with biogeochemical components often fail to generate global-scale anoxia induced by warming alone, unless increased phosphate level is invoked. Here, I use the carbon isotope inversion approach in an Earth system model of intermediate complexity (GENIE) with modern phosphate levels to investigate ocean deoxygenation due to global warming through continuous CO­2 emission. I evaluate the temporal and spatial extent of ocean deoxygenation for a best-fit scenario that represents contact metamorphism of organic-rich sediments (?13C = -25‰) during Siberian Traps volcanism eruption. This scenario is characterized by total peak amount of ~30,000 Gt of carbon and global sea surface temperature increase of 5 oC (Cui et al., 2014). The global surface ocean oxygen concentration shows only a modest decrease (from 230 to 215 µmol kg-1) during peak C emission, whereas the global deep ocean oxygen concentration shows a 70% decrease (from 160 to 50 µmol kg-1). During peak C emission, the oxygen minimum zone (~800 m depth) expands vertically and horizontally, and vast regions in the deep northern Panthalassa becomes hypoxic (press). Spatial and temporal patterns of ocean acidification during the end-Permian mass extinction - An Earth system model evaluation. Volcanism and Global Environmental Change. L. T. elkins-Tanton, Fristad, K. Cambridge, Cambridge University Press.

  15. FAST PYROLYSIS OF ENZYMATIC/MILD ACIDOLYSIS LIGNIN FROM MOSO BAMBOO

    OpenAIRE

    Rui Lou; Shu-bin Wu; Gao-jin Lv

    2010-01-01

    The characteristics of enzymatic/mild acidolysis lignin (EMAL) isolated from moso bamboo were investigated using pyrolysis-gas chromato-graphy/mass spectrometry (Py-GC/MS). Pyrolysis temperature as a factor on products was studied, and the pyrolysis mechanism was inferred with respect to the dominating products. Research results showed that pyrolysis products derived from EMAL pyrolysis were mainly heterocyclic (2,3-dihydrobenzofuran), phenols, esters, and a minor amount of acetic acid. Pyrol...

  16. Low-temperature co-pyrolysis of a low-rank coal and biomass to prepare smokeless fuel briquettes

    Energy Technology Data Exchange (ETDEWEB)

    Blesa, M.J.; Miranda, J.L.; Moliner, R.; Izquierdo, M.T. [Instituto de Carboquimica CSIC, P.O. Box 589, 50080 Zaragoza (Spain); Palacios, J.M. [Instituto de Catalisis y Petroleoquimica CSIC, Cantoblanco, 28049 Madrid (Spain)

    2003-12-01

    Smokeless fuel briquettes have been prepared with low-rank coal and biomass. These raw materials have been mixed in different ratios and have been pyrolysed at 600C with the aim to reduce both the volatile matter and the sulphur content, and to increase the high calorific value (HCV). The co-pyrolysis of coal and biomass has shown a synergetic effect. The biomass favours the release of hydrogen sulphide during the thermal treatment. This fact can be explained in terms of the hydrogen-donor character of the biomass. Moreover, the optimisation of the amount of binder and the influence of different types of biomass in the blend have been studied with respect to the mechanical properties of the briquettes (impact resistance, compression strength and abrasion). Briquettes prepared with sawdust (S) present better mechanical properties than those with olive stones (O) because of its fibrous texture.

  17. Pyrolysis and gasification of coal at high temperatures. Final technical report, September 15, 1987--September 14, 1991

    Energy Technology Data Exchange (ETDEWEB)

    Zygourakis, K.

    1992-02-10

    The macropore structure of chars is a major factor in determining their reactivity during the gasification stage. The major objectives of this contract were to (a) quantify by direct measurements the effect of pyrolysis conditions of the macropore structure, and (b) establish how the macropores affected the reactivity pattern, the ignition behavior and the fragmentation of the char particles during gasification in the regime of strong diffusional limitations. Results from this project provide much needed information on the factors that affect the quality of the solid products (chars) of coal utilization processes (for example, mild gasification processes). The reactivity data will also provide essential parameters for the optimal design of coal gasification processes. (VC)

  18. Effect of Annealing Temperature on Structural, Optical and Electrical Properties of Pure CdS Thin Films Deposited by Spray Pyrolysis Technique

    Directory of Open Access Journals (Sweden)

    2012-12-01

    Full Text Available

    Effect of annealing temperature on the properties of CdS thin films are carried out in this work. Nanocrystalline cadmium sulphide (CdS thin films were prepared using spray pyrolysis deposition (SPD technique and the structural, optical and electrical properties were investigated for different annealing temperature (as deposited, 300, 400 & 500 C. The surface morphology and compositional properties studied by SEM and EDX respectively. The crystal structure of CdS thin film was studied by X-ray diffraction. The crystallite size and lattice constant of SPD CdS thin films were investigated. The optical parameters such as transmittance, absorption coefficient and energy band gap of the films with thermal annealing temperature was investigated by UV/VIS spectrophotometer. The variation of band gap values of CdS thin film samples were found to be in the range of 2.51 to 2.8 eV. Electrical resistivity measurements were carried out in fourprobe Vander Pauw method at different temperature. So CdS films may be a good candidate for suitable application in various optoelectronic devices.

  19. Influence of deposition temperature, solvent, and solute concentration on the deposition mechanisms and final structure of mercury iodide fabricated using the spray pyrolysis technique

    Science.gov (United States)

    Ugucioni, J. C.; Mulato, M.

    2006-08-01

    Mercury iodide (HgI2) samples were deposited by spray pyrolysis under varying fabrication parameters. Different solvents (water and ethanol) and substrate temperatures (from 40 up to 130°C) were used. Yellowish films were obtained using water and temperatures above 100°C, while reddish films were obtained using ethanol and temperatures below 75°C. The structure and the stoichiometry of the samples were investigated using x-ray diffraction, scanning electron microscopy, and energy dispersive spectroscopy. The yellowish films show lattice constants of 4.379, 7.1953, and 12.5505Å that correspond to a space group similar to the structure of the orthorhombic ?-HgI2. The reddish films show lattice constant averages of 4.3550 and 12.2200Å that correspond to a space group similar to the structure of the tetragonal ?-HgI2. We observed problems related to the stoichiometry of the films caused by the volatile characteristic of iodine atoms. Typical thickness can be estimated to be around a few microns. The deposition mechanisms and final structure of the samples are discussed as a function of deposition temperature, type of solvent, and solute concentration. Optimized deposition conditions are presented for the development of thin films for radiation detectors.

  20. Laser induced pyrolysis techniques

    International Nuclear Information System (INIS)

    The application of laser pyrolysis techniques to the problems of chemical analysis is discussed. The processes occurring during laser pyrolysis are first briefly reviewed. The problems encountered in laser pyrolysis gas chromatography are discussed using the analysis of phenanthrene and binary hydrocarbons. The application of this technique to the characterization of naturally occurring carbonaceous material such as oil shales and coal is illustrated

  1. Suspension Combustion of Wood: Influence of Pyrolysis Conditions on Char Yield, Morphology, and Reactivity

    DEFF Research Database (Denmark)

    Dall'Ora, Michelangelo; Jensen, Peter Arendt

    2008-01-01

    Chars from pine and beech wood were produced by fast pyrolysis in an entrained flow reactor and by slow pyrolysis in a thermogravimetric analyzer. The influence of pyrolysis temperature, heating rate and particle size on char yield and morphology was investigated. The applied pyrolysis temperature varied in the range 673?1673 K for slow pyrolysis and between 873 and 1573 K for fast pyrolysis. The chars were oxidized in a thermogravimetric analyzer and the mass loss data were used to determine char oxidation reactivity. Char yield from fast pyrolysis (104?105 K/s) was as low as 1 to 6% on a dry ash free basis, whereas it was about 15?17% for slow pyrolysis (10?20 K/min); char yield decreased as pyrolysis temperature increased. During fast pyrolysis wood particles underwent melting, yet to different extents for the two investigated fuels: pine wood produced chars of porous spherical particles, whereas beech sawdust chars showed a somewhat less drastic change of morphology with respect to the parent fuel. Char produced by low heating rate pyrolysis fully retained the original fibrous structure of wood. Fast pyrolysis chars were significantly more reactive than slow pyrolysis chars; moreover, char oxidation reactivity decreased as pyrolysis temperature increased. The amount and composition of the ash forming matter of the wood fuels seems to play an important role in determining the differences in char yield, morphology and reactivity.

  2. Effects of torrefaction and densification on switchgrass pyrolysis products.

    Science.gov (United States)

    Yang, Zixu; Sarkar, Madhura; Kumar, Ajay; Tumuluru, Jaya Shankar; Huhnke, Raymond L

    2014-12-01

    The pyrolysis behaviors of four types of pretreated switchgrass (torrefied at 230 and 270°C, densification, and torrefaction at 270°C followed by densification) were studied at three temperatures (500, 600, 700°C) using a pyroprobe attached to a gas chromatogram mass spectroscopy (Py-GC/MS). The torrefaction of switchgrass improved its oxygen to carbon ratio and energy content. Contents of anhydrous sugars and phenols in pyrolysis products of torrefied switchgrass were higher than those in pyrolysis products of raw switchgrass. As the torrefaction temperature increased from 230 to 270°C, the contents of anhydrous sugars and phenols in pyrolysis products increased whereas content of guaiacols decreased. High pyrolysis temperature (600 and 700°C as compared to 500°C) enhanced decomposition of lignin and anhydrous sugars, leading to increase in phenols, aromatics and furans. Densification enhanced depolymerization of cellulose and hemicellulose during pyrolysis. PMID:25463807

  3. Effects of torrefaction and densification on switchgrass pyrolysis products

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Z; Sarkar, M; Kumar, A; Jaya Shankar Tumuluru; R.L. Huhnke

    2014-10-01

    Abstract The pyrolysis behaviors of four types of pretreated switchgrass (torrefied at 230 and 270 °C, densification, and torrefaction at 270 ºC followed by densification) were studied at three temperatures (500, 600, 700 ºC) using a pyroprobe attached to a gas chromatogram mass spectroscopy (Py-GC/MS). The torrefaction of switchgrass improved its oxygen to carbon ratio and energy content. Contents of anhydrous sugars and phenols in pyrolysis products of torrefied switchgrass were higher than those in pyrolysis products of raw switchgrass. As the torrefaction temperature increased from 230 to 270 °C, the contents of anhydrous sugars and phenols in pyrolysis products increased whereas content of guaiacols decreased. High pyrolysis temperature (600 and 700 °C as compared to 500 °C) enhanced decomposition of lignin and anhydrous sugars, leading to increase in phenols, aromatics and furans. Densification enhanced depolymerization of cellulose and hemicellulose during pyrolysis.

  4. Coherence length in deoxygenated (1 0 3)/(0 1 3) oriented YBCO superconductor films

    Energy Technology Data Exchange (ETDEWEB)

    Camerlingo, Carlo [Consiglio Nazionale delle Ricerche, Istituto di Cibernetica ' E. Caianiello' , Via Campi Flegrei 34, 80078 Pozzuoli (Italy)], E-mail: c.camerlingo@cib.na.cnr.it; Jung, Grzegorz [Department of Physics, Ben Gurion University of Negev, 84105 Beer Sheva (Israel)

    2007-09-01

    The coherence length {xi}{sub c} along c-axis direction in (1 0 3)/(0 1 3) oriented YBCO superconductor thin films has been evaluated from the temperature dependence of current-voltage (I-V) characteristics of micro-bridges in the framework of a model taking in account thermally activated magnetic flux creep in the intrinsic potential of the layered structure of the superconductor. The coherence length gradually increased from the initial value {xi}{sub c} = 0.14 nm to {xi}{sub c} = 0.33 nm in the sample subjected to subsequent annealing steps performed in air at increasing temperatures from a range T{sub a} = 190-275 deg. C. Structural modifications of deoxygenated samples were monitored by micro-Raman spectroscopy. The critical temperature T{sub c} slightly increases after the initial annealing steps while a significant T{sub c} decrease has been observed after T{sub a} = 275 deg. C stage accompanied by appearance of the tetragonal phase in the crystal structure.

  5. Role of substrate temperature on the properties of Na-doped ZnO thin film nanorods and performance of ammonia gas sensors using nebulizer spray pyrolysis technique

    Energy Technology Data Exchange (ETDEWEB)

    Mariappan, R., E-mail: marijpr@gmail.com [Department of Physics, Sri Ramakrishna Mission Vidyalaya College of Arts and Science, Coimbatore 641 020, Tamil Nadu (India); Department of Physics, Adhiyamaan College of Engineering, Hosur 635 109, Tamilnadu (India); Ponnuswamy, V.; Suresh, R. [Department of Physics, Sri Ramakrishna Mission Vidyalaya College of Arts and Science, Coimbatore 641 020, Tamil Nadu (India); Suresh, P. [Materials Research Centre, Indian Institute of Science, Bangalore 560 012 (India); Chandra Bose, A. [Department of Physics, National Institute of Technology, Tiruchirappalli 620 015, Tamil Nadu (India); Ragavendar, M. [Department of Physics, KPR Institute of Engineering and Technology, Coimbatore 641 407, Tamil Nadu (India)

    2014-01-05

    Highlights: • Na-doped ZnO films deposited on glass by nebulizer spray pyrolysis (NSP) method. • NSP method for large area coatings and good results as compared with other methods. • HR-SEM studies reveal the formation of Na-doped ZnO films consisting of nano-rods. • Na-doped ZnO films ensure their stability and suitability for gas sensors. -- Abstract: Sodium doped zinc oxide (Na:ZnO) thin films were deposited on glass substrates at substrate temperatures 300, 400 and 500 °C by a novel nebulizer spray method. X-ray diffraction shows that all the films are polycrystalline in nature having hexagonal structure with high preferential orientation along (0 0 2) plane. High resolution SEM studies reveal the formation of Na-doped ZnO films having uniformly distributed nano-rods over the entire surface of the substrates at 400 °C. The complex impedance of the ZnO nano-rods shows two distinguished semicircles and the diameter of the arcs got decreased in diameter as the temperature increases from 170 to 270 °C and thereafter slightly increased.

  6. Effect of gamma ray irradiation on deoxygenation by hydrazine in artificial seawater

    International Nuclear Information System (INIS)

    At the spent nuclear fuel pools in the Fukushima Daiichi Nuclear Power Plant, hydrazine has been added to reduce dissolved oxygen in the pool water containing salts. The reduction behavior of dissolved oxygen in seawater with hydrazine in the presence of radiation is unknown. The effect of gamma ray irradiation on deoxygenation by hydrazine in artificial seawater was investigated at room temperature. We placed the artificial seawater with a small amount of hydrazine under gamma ray irradiation at dose rates of 0.3-7.5 kGy/h. The concentration of dissolved oxygen in the solutions was measured before and after the irradiation. The concentration of dissolved oxygen hardly decreased in the absence of gamma radiation in a few hours, whereas it markedly decreased in the presence of gamma radiation. The concentration of dissolved oxygen decreased with irradiation time. At this moment, hydrazine concentration decreased more than twice the dissolved oxygen concentration. This shows that some gamma radiolysis products of hydrazine act as deoxidizers. The concentration of dissolved oxygen in artificial seawater could be decreased by the addition of a small amount of hydrazine in the presence of gamma radiation at room temperature. (author)

  7. PROPERTIES OF GAS AND CHAR FROM MICROWAVE PYROLYSIS OF PINE SAWDUST

    OpenAIRE

    Xian-Hua Wang; Han-Ping Chen; Xue-Jun Ding; Hai-Ping Yang; Shi-Hong Zhang; Ying-Qiang Shen

    2009-01-01

    Pine sawdust pyrolysis was carried out respectively using microwave and conventional electrical heating at different temperatures in order to understand the properties of pyrolytic products from microwave pyrolysis of biomass. Less char material was obtained by microwave pyrolysis compared to conventional heating at the same temperature. While comparing the components of the pyrolytic gases, it was revealed that the microwave pyrolysis gas usually had higher H2 and CO contents and lower CH4...

  8. SIMULATION OF OLIVE PITS PYROLYSIS IN A ROTARY KILN PLANT

    OpenAIRE

    Giacobbe Braccio; Vincenzo Lorefice; Cesare Freda; Enzo Benanti; Vinod Kumar Sharma

    2011-01-01

    This work deals with the simulation of an olive pits fed rotary kiln pyrolysis plant installed in Southern Italy. The pyrolysis process was simulated by commercial software CHEMCAD. The main component of the plant, the pyrolyzer, was modelled by a Plug Flow Reactor in accordance to the kinetic laws. Products distribution and the temperature profile was calculated along reactor's axis. Simulation results have been found to fit well the experimental data of pyrolysis. Moreover, sensitivity anal...

  9. Fast Pyrolysis of Lignin Using a Pyrolysis Centrifuge Reactor

    DEFF Research Database (Denmark)

    Trinh, Ngoc Trung; Jensen, Peter Arendt

    2013-01-01

    Fast pyrolysis of lignin from an ethanol plant was investigated on a lab scale pyrolysis centrifuge reactor (PCR) with respect to pyrolysis temperature, reactor gas residence time, and feed rate. A maximal organic oil yield of 34 wt % dry basis (db) (bio-oil yield of 43 wt % db) is obtained at temperatures of 500?550 °C, reactor gas residence time of 0.8 s, and feed rate of 5.6 g/min. Gas chromatography mass spectrometry and size-exclusion chromatography were used to characterize the Chemical properties of the lignin oils. Acetic acid, levoglucosan, guaiacol, syringols, and p-vinylguaiacol are found to be major chemical components in the lignin oil. The maximal yields of 0.62, 0.67, and 0.38 wt % db were obtained for syringol, p-vinylguaiacol, and guaiacol, respectively. The reactor temperature effect was investigated in a range of 450?600 °C and has a considerable effect on the observed chemical components and molecular mass distribution of the lignin oils. The obtained lignin oil has a very different components composition when compared to a beech wood oil.

  10. The influence of the pyrolysis temperature on the electrochemical behavior of carbon-rich SiCN polymer-derived ceramics as anode materials in lithium-ion batteries

    Science.gov (United States)

    Reinold, Lukas Mirko; Yamada, Yuto; Graczyk-Zajac, Magdalena; Munakata, Hirokazu; Kanamura, Kiyoshi; Riedel, Ralf

    2015-05-01

    Within this study we report on the impact of the pyrolysis temperature on the structural and electrochemical properties of the poly(phenylvinylsilylcarbodiimide) derived silicon carbonitride (SiCN) ceramic. Materials pyrolysed at 800 °C and 1300 °C, SiCN 800 and SiCN 1300, are found amorphous. Raman spectroscopy measurements indicate the increase in ordering of the free carbon phase with increasing pyrolysis temperature which leads to lower capacity recovered by SiCN 1300. Significant hysteresis is found for materials pyrolysed at 800 °C during electrochemical lithium insertion/extraction. This feature is attributed to much higher hydrogen content in SiCN 800 sample. An aging of SiCN 800 reflected by a change of elemental composition upon contact to air and a strong film formation are attenuated at a higher pyrolysis temperature. Single particle microelectrode investigation on SiCN 800 and SiCN 1300 clarify different electrochemical behavior of the materials. Much lower charge transfer resistance of SiCN 1300 in comparison to SiCN 800 explains better high currents electrochemical performance. Lithium ions diffusion coefficient Dmin ranges from 3.2 10-9 cm2s-1 to 6.4 10-11 cm2s-1 and is independent on the potential.

  11. Orientation-dependent low field magnetic anomalies and room-temperature spintronic material – Mn doped ZnO films by aerosol spray pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Nkosi, S.S. [CSIR-National Laser Centre, 626 Meiring Naude Rd, Brummeria, Pretoria 0001 (South Africa); School of Physics, University of Witwatersrand, Private Bag X3, Johannesburg 2030 (South Africa); Kortidis, I. [Institute of Electronic Structure and Laser, Foundation for Research and Technology, Hellas, P.O. Box 1527, 71110 Heraklion, Crete (Greece); Motaung, D.E., E-mail: dmotaung@csir.co.za [DST/CSIR Nanotechnology Innovation Centre, National Centre for Nano-Structured Materials, Council for Scientific and Industrial Research, P.O. Box 395, Pretoria 0001 (South Africa); Malgas, G.F. [DST/CSIR Nanotechnology Innovation Centre, National Centre for Nano-Structured Materials, Council for Scientific and Industrial Research, P.O. Box 395, Pretoria 0001 (South Africa); Department of Physics, University of the Western Cape, Private Bag X17, Bellville, 7535 (South Africa); Keartland, J.; Sideras-Haddad, E. [School of Physics, University of Witwatersrand, Private Bag X3, Johannesburg 2030 (South Africa); Forbes, A. [CSIR-National Laser Centre, 626 Meiring Naude Rd, Brummeria, Pretoria 0001 (South Africa); School of Physics, University of Witwatersrand, Private Bag X3, Johannesburg 2030 (South Africa); Mwakikunga, B.W., E-mail: bmwakikunga@csir.co.za [DST/CSIR Nanotechnology Innovation Centre, National Centre for Nano-Structured Materials, Council for Scientific and Industrial Research, P.O. Box 395, Pretoria 0001 (South Africa); Sinha-Ray, S. [DST/CSIR Nanotechnology Innovation Centre, National Centre for Nano-Structured Materials, Council for Scientific and Industrial Research, P.O. Box 395, Pretoria 0001 (South Africa); Kiriakidis, G. [Institute of Electronic Structure and Laser, Foundation for Research and Technology, Hellas, P.O. Box 1527, 71110 Heraklion, Crete (Greece)

    2013-12-05

    Graphical abstract: Optical microscopy images of Mn doped ZnO films deposited for 20 min. Highlights: •Mn–ZnO films showing transparent spherical bubbles were synthesized by ASP. •LFMA phenomenon was observed for these films. •A relatively novel reversal magnetic feature to that of LFMA was observed. •Ferromagnetic to paramagnetic transition due to Mn doping was observed. •Angular dependence analysis showed evidence of magnetic anisotropy present. -- Abstract: High quality un-doped and Mn-doped ZnO films deposited by a simple aerosol spray pyrolysis technique for 20 and 30 min were studied using electron paramagnetic resonance (EPR), X-ray diffraction (XRD) and atomic force microscopy (AFM) techniques. EPR analysis showed novel observation of low field microwave absorption (LFMA) on the manganese (Mn) doped zinc oxide (ZnO) films at various Mn concentrations. The results showed a peculiar behavior, reversal signal to that of LFMA. These findings also demonstrated that these films contain ferromagnetism at room temperature with possible applications in spintronics. Angular dependence measurements were found to induce magnetic transition from ferromagnetism to paramagnetism. Structural analysis showed that the undertaken materials are in wurtzite structures. The light absorption edge of Mn–ZnO films red shifted which enhanced the observed ferromagnetism. The direct modulation of the band gap caused by Mn–ZnO substitution is responsible for the red shift effect in absorption edge of ZnO.

  12. Orientation-dependent low field magnetic anomalies and room-temperature spintronic material – Mn doped ZnO films by aerosol spray pyrolysis

    International Nuclear Information System (INIS)

    Graphical abstract: Optical microscopy images of Mn doped ZnO films deposited for 20 min. Highlights: •Mn–ZnO films showing transparent spherical bubbles were synthesized by ASP. •LFMA phenomenon was observed for these films. •A relatively novel reversal magnetic feature to that of LFMA was observed. •Ferromagnetic to paramagnetic transition due to Mn doping was observed. •Angular dependence analysis showed evidence of magnetic anisotropy present. -- Abstract: High quality un-doped and Mn-doped ZnO films deposited by a simple aerosol spray pyrolysis technique for 20 and 30 min were studied using electron paramagnetic resonance (EPR), X-ray diffraction (XRD) and atomic force microscopy (AFM) techniques. EPR analysis showed novel observation of low field microwave absorption (LFMA) on the manganese (Mn) doped zinc oxide (ZnO) films at various Mn concentrations. The results showed a peculiar behavior, reversal signal to that of LFMA. These findings also demonstrated that these films contain ferromagnetism at room temperature with possible applications in spintronics. Angular dependence measurements were found to induce magnetic transition from ferromagnetism to paramagnetism. Structural analysis showed that the undertaken materials are in wurtzite structures. The light absorption edge of Mn–ZnO films red shifted which enhanced the observed ferromagnetism. The direct modulation of the band gap caused by Mn–ZnO substitution is responsible for the red shift effect in absorption edge of ZnO

  13. Structural and optical properties of ZnO nanostructures grown by aerosol spray pyrolysis: Candidates for room temperature methane and hydrogen gas sensing

    International Nuclear Information System (INIS)

    We report on the synthesis of ZnO films by aerosol spray pyrolysis method at different deposition times. The surface morphology, crystal structure and the cross-sectional analysis of the prepared ZnO films were characterized by X-ray diffraction (XRD), focused ion beam scanning electron microscopy (FIB-SEM), atomic force microscopy (AFM) and high resolution transmission electron microscopy (HR-TEM). XRD analysis revealed that the ZnO films are polycrystalline in nature. Structural analysis exploiting cross-sectional TEM profile showed that the films composed of nano-particles and columnar structures growing perpendicular to the substrate. AFM revealed that the columnar structures have a higher surface roughness as compared to the nanoparticles. The effect of ZnO crystallite size and crystallinity on the gas sensing performance of hydrogen and methane gases was also evaluated. Sensing film based on ZnO nanoparticles has numerous advantages in terms of its reliability and high sensitivity. These sensing materials revealed an improved response to methane and hydrogen gases at room temperature due to their high surface area, indicating their possible application as a gas sensor.

  14. Effect of Solution Molarity, Substrate Temperature and Spray Time on The Structural and Optical Properties Of ZnO Thin Films Deposited By Spray Pyrolysis

    International Nuclear Information System (INIS)

    Zinc oxide thin films were deposited on a glass substrate by spray pyrolysis technique using solution of zinc acetate and air as the carrier gas. Effects of solution molarity, substrate temperature and spray time on films properties were investigated. All films deposited were characterized using X-ray diffraction for structural characterization and UV-VIS transmission spectrophotometry for optical properties. According to the analytical method, the type of crystal lattice was found to be hexagonal and X-ray diffraction (XRD) patterns showed that the films deposited were polycrystalline with (002) plane as preferential orientation. The values of lattice constant, grain size, micro strain and dislocation density of all samples were calculated. In addition, Optical behaviors of film samples were analyzed by obtaining transmission spectra, in the wavelength range of 350-800 nm. The UV-VIS spectroscopy shows the high transparency of ZnO films in the UV region. An optimization of the films has been carried out to determine the best preparation conditions.

  15. Structural and optical properties of ZnO nanostructures grown by aerosol spray pyrolysis: Candidates for room temperature methane and hydrogen gas sensing

    Energy Technology Data Exchange (ETDEWEB)

    Motaung, D.E., E-mail: dmotaung@csir.co.za [DST/CSIR Nanotechnology Innovation Centre, National Centre for Nano-Structured Materials, Council for Scientific and Industrial Research, P. O. Box 395, Pretoria 0001 (South Africa); Mhlongo, G.H., E-mail: gmhlongo@csir.co.za [DST/CSIR Nanotechnology Innovation Centre, National Centre for Nano-Structured Materials, Council for Scientific and Industrial Research, P. O. Box 395, Pretoria 0001 (South Africa); Kortidis, I. [Transparent Conductive Materials Lab, Institute of Electronic Structure and Laser, Foundation for Research and Technology Hellas, 100N. Plastira str., Vassilika Vouton, 70013 Heraklion, Crete (Greece); Nkosi, S.S., E-mail: skosi@csir.co.za [CSIR-National Laser Centre, 626 Meiring Naude Rd, Brummeria, Pretoria 0001 (South Africa); School of Physics, University of Witwatersrand, Private Bag X3, Johannesburg 2030 (South Africa); Malgas, G.F.; Mwakikunga, B.W.; Ray, S.Sinha [DST/CSIR Nanotechnology Innovation Centre, National Centre for Nano-Structured Materials, Council for Scientific and Industrial Research, P. O. Box 395, Pretoria 0001 (South Africa); Kiriakidis, G., E-mail: kiriakid@iesl.forth.gr [Transparent Conductive Materials Lab, Institute of Electronic Structure and Laser, Foundation for Research and Technology Hellas, 100N. Plastira str., Vassilika Vouton, 70013 Heraklion, Crete (Greece); University of Crete, Department of Physics, 710 03 Heraklion, Crete (Greece)

    2013-08-15

    We report on the synthesis of ZnO films by aerosol spray pyrolysis method at different deposition times. The surface morphology, crystal structure and the cross-sectional analysis of the prepared ZnO films were characterized by X-ray diffraction (XRD), focused ion beam scanning electron microscopy (FIB-SEM), atomic force microscopy (AFM) and high resolution transmission electron microscopy (HR-TEM). XRD analysis revealed that the ZnO films are polycrystalline in nature. Structural analysis exploiting cross-sectional TEM profile showed that the films composed of nano-particles and columnar structures growing perpendicular to the substrate. AFM revealed that the columnar structures have a higher surface roughness as compared to the nanoparticles. The effect of ZnO crystallite size and crystallinity on the gas sensing performance of hydrogen and methane gases was also evaluated. Sensing film based on ZnO nanoparticles has numerous advantages in terms of its reliability and high sensitivity. These sensing materials revealed an improved response to methane and hydrogen gases at room temperature due to their high surface area, indicating their possible application as a gas sensor.

  16. Pyrolysis and co-pyrolysis of Laminaria japonica and polypropylene over mesoporous Al-SBA-15 catalyst

    OpenAIRE

    Lee, Hyung Won; Choi, Suek Joo; Park, Sung Hoon; Jeon, Jong-Ki; Jung, Sang-Chul; Kim, Sang Chai; Park, Young-Kwon

    2014-01-01

    The catalytic co-pyrolysis of a seaweed biomass, Laminaria japonica, and a typical polymer material, polypropylene, was studied for the first time. A mesoporous material Al-SBA-15 was used as a catalyst. Pyrolysis experiments were conducted using a fixed-bed reactor and pyrolysis gas chromatography/mass spectrometry (Py-GC/MS). BET surface area, N2 adsorption-desorption isotherms, and NH3 temperature programmed desorption were measured to examine the catalyst characteristics. When only L. jap...

  17. PROPERTIES OF GAS AND CHAR FROM MICROWAVE PYROLYSIS OF PINE SAWDUST

    Directory of Open Access Journals (Sweden)

    Xian-Hua Wang

    2009-08-01

    Full Text Available Pine sawdust pyrolysis was carried out respectively using microwave and conventional electrical heating at different temperatures in order to understand the properties of pyrolytic products from microwave pyrolysis of biomass. Less char material was obtained by microwave pyrolysis compared to conventional heating at the same temperature. While comparing the components of the pyrolytic gases, it was revealed that the microwave pyrolysis gas usually had higher H2 and CO contents and lower CH4 and CO2 contents than those obtained by conventional pyrolysis at the same temperature. The texture analysis results of the microwave pyrolysis chars showed that the chars would melt and the pores would shrink at high temperatures, and hence, the specific surface areas of the chars decreased with increasing temperature. Similarly, the reactivity of the char was remarkably reduced when the microwave pyrolysis temperature exceeded 600°C.

  18. Fatigue life and crack growth mechanisms of the type 316LN austenitic stainless steel in 310degC deoxygenated water

    International Nuclear Information System (INIS)

    The low cycle fatigue tests of the type 316LN stainless steel were conducted to investigate the cracking mechanisms in high-temperature water. The fatigue lives of the specimens tested in 310degC deoxygenated water were considerably shorter than those tested in air. For the specimens tested in 310degC deoxygenated water, the evidences for the metal dissolution such as the stream downed feature, the blunt crack shape, and the wider crack opening were observed but rather weakly. In the same specimens, the evidences for the hydrogen-induced cracking such as the coalescence of microvoids and the decrease of the dislocation spacing at the crack tip were observed rather clearly. Therefore, it is thought that the hydrogen-induced cracking is mainly responsible for the reduction in the fatigue life of the type 316LN stainless steel in 310degC deoxygenated water while the effect of metal dissolution is less significant. The hydrogen-induced cracking is more pronounced in the slower strain rates. This behavior is in accordance with the larger reduction in the fatigue life at the slower strain rates. Furthermore, the fatigue life and the dislocation spacing show the minimum value in the strain rate range from 0.008 to 0.04%/s, which indicates the existence of the critical strain rate. (author)

  19. Pyrolysis and Gasification

    OpenAIRE

    Astrup, Thomas; Bilitewski, B.

    2010-01-01

    Pyrolysis and gasification include processes that thermally convert carbonaceous materials into products such as gas, char, coke, ash, and tar. Overall, pyrolysis generates products like gas, tar, and char, while gasification converts the carboncontaining materials (e.g. the outputs from pyrolysis) into a mainly gaseous output. The specific output composition and relative amounts of the outputs greatly depend on the input fuel and the overall process configuration. Although pyroly...

  20. Pyrolysis of waste tyres: A review

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • Pyrolysis of waste tyres produces oil, gas and char, and recovered steel. • Batch, screw kiln, rotary kiln, vacuum and fluidised-bed are main reactor types. • Product yields are influenced by reactor type, temperature and heating rate. • Pyrolysis oils are complex and can be used as chemical feedstock or fuel. • Research into higher value products from the tyre pyrolysis process is reviewed. - Abstract: Approximately 1.5 billion tyres are produced each year which will eventually enter the waste stream representing a major potential waste and environmental problem. However, there is growing interest in pyrolysis as a technology to treat tyres to produce valuable oil, char and gas products. The most common reactors used are fixed-bed (batch), screw kiln, rotary kiln, vacuum and fluidised-bed. The key influence on the product yield, and gas and oil composition, is the type of reactor used which in turn determines the temperature and heating rate. Tyre pyrolysis oil is chemically very complex containing aliphatic, aromatic, hetero-atom and polar fractions. The fuel characteristics of the tyre oil shows that it is similar to a gas oil or light fuel oil and has been successfully combusted in test furnaces and engines. The main gases produced from the pyrolysis of waste tyres are H2, C1–C4 hydrocarbons, CO2, CO and H2S. Upgrading tyre pyrolysis products to high value products has concentrated on char upgrading to higher quality carbon black and to activated carbon. The use of catalysts to upgrade the oil to a aromatic-rich chemical feedstock or the production of hydrogen from waste tyres has also been reported. Examples of commercial and semi-commercial scale tyre pyrolysis systems show that small scale batch reactors and continuous rotary kiln reactors have been developed to commercial scale

  1. Solar heated oil shale pyrolysis process

    Science.gov (United States)

    Qader, S. A. (inventor)

    1985-01-01

    An improved system for recovery of a liquid hydrocarbon fuel from oil shale is presented. The oil shale pyrolysis system is composed of a retort reactor for receiving a bed of oil shale particules which are heated to pyrolyis temperature by means of a recycled solar heated gas stream. The gas stream is separated from the recovered shale oil and a portion of the gas stream is rapidly heated to pyrolysis temperature by passing it through an efficient solar heater. Steam, oxygen, air or other oxidizing gases can be injected into the recycle gas before or after the recycle gas is heated to pyrolysis temperature and thus raise the temperature before it enters the retort reactor. The use of solar thermal heat to preheat the recycle gas and optionally the steam before introducing it into the bed of shale, increases the yield of shale oil.

  2. PRONOUNCED MUSCLE DEOXYGENATION DURING SUPRAMAXIMAL EXERCISE UNDER SIMULATED HYPOXIA IN SPRINT ATHLETES

    Directory of Open Access Journals (Sweden)

    Kazuo Oguri

    2008-12-01

    Full Text Available The purpose of this study was to determine whether acute hypoxia alters the deoxygenation level in vastus lateralis muscle during a 30 s Wingate test, and to compare the muscle deoxygenation level between sprint athletes and untrained men. Nine male track sprinters (athletic group, VO2max 62.5 ± 4.1 ml/kg/min and 9 healthy untrained men (untrained group, VO2max 49.9 ± 5.2 ml·kg-1·min-1 performed a 30 s Wingate test under simulated hypoxic (FIO2 = 0.164 and PIO2 = 114 mmHg and normoxic conditions. During the exercise, changes in oxygenated hemoglobin (OxyHb in the vastus lateralis were measured using near infrared continuous wave spectroscopy. Decline in OxyHb, that is muscle deoxygenation, was expressed as percent change from baseline. Percutaneous arterial oxygen saturation (SpO2, oxygen uptake (VO2, and ventilation (VE were measured continuously. In both groups, there was significantly greater muscle deoxygenation, lower SpO2, lower peakVO2, and higher peakVE during supramaximal exercise under hypoxia than under normoxia, but no differences in peak and mean power output during the exercise. Under hypoxia, the athletic group experienced significantly greater muscle deoxygenation, lower SpO2, greater decrement in peakVO2 and increment in peakVE during the exercise than the untrained group. When the athletic and untrained groups were pooled, the increment of muscle deoxygenation was strongly correlated with lowest SpO2 in the 30 s Wingate test under hypoxia. These results suggest that acute exposure to hypoxia causes a greater degree of peripheral muscle deoxygenation during supramaximal exercise, especially in sprint athletes, and this physiological response would be explained mainly by lower arterial oxygen saturation

  3. CATALYTIC FAST PYROLYSIS OF CELLULOSE MIXED WITH SULFATED TITANIA TO PRODUCE LEVOGLUCOSENONE: ANALYTICAL PY-GC/MS STUDY

    OpenAIRE

    Qiang Lu,; Xu-Ming Zhang,; Zhi-Bo Zhang; Ying Zhang(School of Science, Xi’an Jiaotong University, Xi’an 710049, P.R. China); Xi-Feng Zhu,; Chang-Qing Dong

    2012-01-01

    Sulfated titania (SO42-/TiO2) was prepared and used for catalytic fast pyrolysis of cellulose to produce levoglucosenone (LGO), a valuable anhydrosugar product. Analytical pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) technique was employed in this study to achieve the catalytic fast pyrolysis of cellulose and on-line analysis of the pyrolysis vapors. Experiments were performed to investigate the effects of several factors on the LGO production, i.e. pyrolysis temperature, cellulo...

  4. Pyrolysis of rubber gloves in integral pyrolysis test plant

    International Nuclear Information System (INIS)

    Previously, pyrolysis of rubber gloves in laboratory study was described. In order to visualize the practical application of rubber gloves pyrolysis in terms of treating rubber gloves in medical waste, a new test plant was designed and constructed. The semi-continuous test plant was designed to accommodate rubber gloves that were not cut or shredded. The test plant has a capacity of 2kg/ hr and employed auxiliary fuel instead of the conventional electrical power for heating. The concept was based on moving bed reactor, but additional feature of sand jacket feature was also introduced in the design. Pyrolysis of the gloves was conducted at three temperatures, namely 350 degree Celsius, 400 degree Celsius and 450 degree Celsius. Oxygen presents inside of the reactor due to the combined effect of imperfect sealing and suction effect. This study addresses the performance of this test plant covering the time temperature profile, gas evolution profile and product yield. Comparison between the yield of the liquid, gas and char pyrolyzate was made against the laboratory study. It was found that the oil yield was less than the one obtained from bench scale study. Water formation was more pronounced. The presence of the oxygen also altered the tail gas composition but eliminate the sticky nature of solid residue, making it easier to handle. The chemical composition of the oil was determined and the main compounds in the oil were esters and phtalic acid. (author)and phtalic acid. (author)

  5. Deoxygenation of glycolaldehyde and furfural on Mo2C/Mo(100)

    Science.gov (United States)

    McManus, Jesse R.; Vohs, John M.

    2014-12-01

    The desire to produce fuels and chemicals in an energy conscious, environmentally sympathetic approach has motivated considerable research on the use of cellulosic biomass feedstocks. One of the major challenges facing the utilization of biomass is finding effective catalysts for the efficient and selective removal of oxygen from the highly-oxygenated, biomass-derived platform molecules. Herein, a study of the reaction pathways for the biomass-derived platform molecule furfural and biomass-derived sugar model compound glycolaldehyde provides insight into the mechanisms of hydrodeoxygenation (HDO) on a model molybdenum carbide catalyst, Mo2C/Mo(100). Using temperature programmed desorption (TPD) and high resolution electron energy loss spectroscopy (HREELS), it was found that the Mo2C/Mo(100) catalyst was active for selective deoxygenation of the aldehyde carbonyl by facilitating adsorption of the aldehyde in an ?2(C,O) bonding configuration. Furthermore, the catalyst showed no appreciable activity for furanic ring hydrogenation, highlighting the promise of relatively inexpensive Mo2C catalysts for selective HDO chemistry.

  6. SIMULATION OF OLIVE PITS PYROLYSIS IN A ROTARY KILN PLANT

    Directory of Open Access Journals (Sweden)

    Giacobbe Braccio

    2011-01-01

    Full Text Available This work deals with the simulation of an olive pits fed rotary kiln pyrolysis plant installed in Southern Italy. The pyrolysis process was simulated by commercial software CHEMCAD. The main component of the plant, the pyrolyzer, was modelled by a Plug Flow Reactor in accordance to the kinetic laws. Products distribution and the temperature profile was calculated along reactor's axis. Simulation results have been found to fit well the experimental data of pyrolysis. Moreover, sensitivity analyses were executed to investigate the effect of biomass moisture on the pyrolysis process.

  7. Temperature dependant physical properties of CdIn2O4 thin films grown by spray pyrolysis

    Science.gov (United States)

    Deokate, R. J.

    2014-12-01

    Transparent conducting cadmium indium oxide films (CdIn2O4) were deposited on glass substrates at temperature of 350 and 400 °C. The film structure and surface morphologies were investigated as a function of temperature by X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The XRD results showed the single phase formation of the material that revealed the presence of Cd2+ and In3+ in the inverse spinel related structure. The chemical compositional analysis of CdIn2O4 films was carried out by X-ray photoelectron spectroscopy (XPS). Room temperature photoluminescence (PL) measurements indicate that the annealed CdIn2O4 thin film exhibit blue shift effect. The optical band gap of CdIn2O4 film was increased from 3.08 to 3.2 eV up to 400 °C.

  8. Characterization of pyrolysis products from a biodiesel phenolic urethane binder.

    Science.gov (United States)

    Wang, Yujue; Cannon, Fred S; Salama, Magda; Fonseca, Dania A; Giese, Scott

    2009-03-01

    Analytical pyrolysis was conducted to identify and quantify the major pyrolysis products of a biodiesel phenolic urethane binder as a function of temperature. This biodiesel binder has been used in U.S. foundries recently to replace conventional phenolic urethane binders for making sand cores. Flash pyrolysis and thermogravimetric analytical (TGA) slow pyrolysis were conducted for the core samples to simulate some key features of the heating conditions that the core binders would experience during metal casting. Pyrolysis products from flash and TGA pyrolysis were analyzed with gas chromatography-mass spectrometry/flame ionization detection/thermal conductivity detection. The evolution profiles of the pyrolysis products during TGA slow pyrolysis were also monitored via thermogravimetry-mass spectrometry (TG-MS). The combination of TG-MS and TGA pyrolysis emission data facilitated a quantification of gaseous pyrolysis products of the biodiesel binder as a function of temperature. The major monitored carbonaceous pyrolysis products of the biodiesel binder included CO, CO2, CH4, and a variety of methyl esters such as dimethyl glutarate, dimethyl adipate, and methyl oleate. These latter species were the components of the biodiesel binder's solvent Pyrolysis of the biodiesel binder also generated a variety of hazardous air pollutants listed by the U.S. EPA, with benzene, toluene, xylene, phenol, and cresols being the prominent species. A considerable fraction of the binder's released mass did not appear as exhausted volatile carbonaceous species, but rather recondensed before they exhausted from the TGA. This represented mass that could likewise recondense within a green sand molding system during full-scale operations, as an environmentally favorable containment of air emissions. PMID:19350935

  9. Thermogravimetric Analysis and Global Kinetics of Segregated MSW Pyrolysis

    Directory of Open Access Journals (Sweden)

    Dwi Aries Himawanto

    2011-12-01

    Full Text Available Municipal Solid Wastes (MSW has great potential as a clean, renewable feedstock for producing modern energy carriers through thermochemical, called pyrolysis. However, despite their enormous potential as energy sources, their thermal characteristics are still not well known. Investigations about segregated MSW slow pyrolysis behaviors have done using macro balance apparatus. Four components of segregated MSW (bamboo wastes, banana leaves wastes, snack wrap wastes and styrofoam wastes and their bleds were thermally degraded through thermogravimetry analysis and their characteristics such as pyrolysis profiles and activation energies were analysed and calculated. About 20 grams of samples pyrolysed under 100 ml/min N2 at constant heating rate 10 0C/min from room temperature to 400 0C final pyrolysis temperature which kept constant for 30 minutes. The nitrogen flow as swept gas which ensures an inert atmosphere during the pyrolysis test.In order to indenty the pyrolysis characteristics of samples, thermogravimetry analysis performed. The recorded data were weight losses and  sample temperature during the pyrolisis process. The results of the research showed bamboo wastes and banana leaves wastes could be catogorized as low stability organics, while snack wrap wastes could be catagorized as polymer mixture materials and styrofoam wastes could be catagorized as plastic materials.Meanwhile the blends materials pyrolysis profiles followed the their components characteristics which signed with the peak temperature which occured. This study also found that global kinetic method could to calculate the pyrolysis activation energy

  10. STEPWISE ISOTHERMAL FAST PYROLYSIS (SIFP). PART II. SIFP OF PEANUT SHELLS - ANTIFUNGAL PROPERTIES OF PHENOLIC FRACTIONS

    OpenAIRE

    Jorge Daniel Pérez; Guadalupe L. Isasmendi; Rosana Alarcón; Patricia López Rivilli

    2011-01-01

    Pyrolysis of peanut shells was carried out using stepwise isothermal fast pyrolysis (SIFP). SIFP consists of successive isothermal fast pyrolysis reactions, where solid products obtained in the previous isothermal fast pyrolysis become the substrate of the subsequent reaction at a higher temperature. This article reports results obtained from SIFP of peanut shells between 200 and 300°C using 100°C intervals under vacuum (0.2 mm). The maximum yield of liquid products was obtained at 300°C, giv...

  11. Pyrolysis system evaluation study

    Science.gov (United States)

    1974-01-01

    An evaluation of two different pyrolysis concepts which recover energy from solid waste was conducted in order to determine the merits of each concept for integration into a Integrated Utility System (IUS). The two concepts evaluated were a Lead Bath Furnace Pyrolysis System and a Slagging Vertical Shaft, Partial Air Oxidation Pyrolysis System. Both concepts will produce a fuel gas from the IUS waste and sewage sludge which can be used to offset primary fuel consumption in addition to the sanitary disposal of the waste. The study evaluated the thermal integration of each concept as well as the economic impact on the IUS resulting from integrating each pyrolysis concepts. For reference, the pyrolysis concepts were also compared to incineration which was considered the baseline IUS solid waste disposal system.

  12. Analyses of residual iron in carbon nanotubes produced by camphor/ferrocene pyrolysis and purified by high temperature annealing

    Energy Technology Data Exchange (ETDEWEB)

    Antunes, E.F., E-mail: ericafa@las.inpe.br [Instituto Tecnologico de Aeronautica (ITA), Praca Marechal Eduardo Gomes, 50, CEP 12.228-900, Sao Jose dos Campos, SP (Brazil); Instituto Nacional de Pesquisas Espaciais (INPE), Av. dos Astronautas, 1758, CEP 12.227-010, Sao Jose dos Campos, SP (Brazil); Resende, V.G. de; Mengui, U.A. [Instituto Nacional de Pesquisas Espaciais (INPE), Av. dos Astronautas, 1758, CEP 12.227-010, Sao Jose dos Campos, SP (Brazil); Cunha, J.B.M. [Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Goncalves, 9500, CEP 91.501-970, Porto Alegre, RS (Brazil); Corat, E.J.; Massi, M. [Instituto Nacional de Pesquisas Espaciais (INPE), Av. dos Astronautas, 1758, CEP 12.227-010, Sao Jose dos Campos, SP (Brazil)

    2011-07-01

    A detailed analysis of iron-containing phases in multiwall carbon nanotube (MWCNT) powder was carried out. The MWCNTs were produced by camphor/ferrocene and purified by high temperature annealing in an oxygen-free atmosphere (N{sub 2} or VC). Thermogravimetric analysis, Moessbauer spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy enabled the evaluation of the residual iron in MWCNTs after purification. The VC treatments provided MWCNTs with a purity degree higher than 99%. Moreover, Raman spectroscopy revealed a significant improvement in graphitic ordering after thermal annealing. A brief description of the mechanism of iron removal was included. We highlight the mobility of iron atoms through graphitic sheets and the large contact angle of iron clusters formed on MWCNT surfaces at high temperatures.

  13. Spray pyrolysis for high Tc superconductors films

    International Nuclear Information System (INIS)

    Spray pyrolysis at high temperature is reviewed and applied to the formation of epitaxial thick layers of YBa2Cu3O7 (YBCO). The necessary conditions to enhance the texture quality and the critical current density are discussed. High critical current densities, over 1.0 MA cm-2 (at 77 K, self-field), are reported, making this technique very promising for low cost applications. This emphasizes the need for more comprehensive studies regarding the chemical phenomena involved in film deposition by spray pyrolysis at high temperature, especially those concerning local equilibrium and reactions occurring in the area involved in the deposition

  14. Reprint of: Pyrolysis technologies for municipal solid waste: a review.

    Science.gov (United States)

    Chen, Dezhen; Yin, Lijie; Wang, Huan; He, Pinjing

    2015-03-01

    Pyrolysis has been examined as an attractive alternative to incineration for municipal solid waste (MSW) disposal that allows energy and resource recovery; however, it has seldom been applied independently with the output of pyrolysis products as end products. This review addresses the state-of-the-art of MSW pyrolysis in regards to its technologies and reactors, products and environmental impacts. In this review, first, the influence of important operating parameters such as final temperature, heating rate (HR) and residence time in the reaction zone on the pyrolysis behaviours and products is reviewed; then the pyrolysis technologies and reactors adopted in literatures and scale-up plants are evaluated. Third, the yields and main properties of the pyrolytic products from individual MSW components, refuse-derived fuel (RDF) made from MSW, and MSW are summarised. In the fourth section, in addition to emissions from pyrolysis processes, such as HCl, SO2 and NH3, contaminants in the products, including PCDD/F and heavy metals, are also reviewed, and available measures for improving the environmental impacts of pyrolysis are surveyed. It can be concluded that the single pyrolysis process is an effective waste-to-energy convertor but is not a guaranteed clean solution for MSW disposal. Based on this information, the prospects of applying pyrolysis technologies to dealing with MSW are evaluated and suggested. PMID:25700606

  15. Pyrolysis technologies for municipal solid waste: a review.

    Science.gov (United States)

    Chen, Dezhen; Yin, Lijie; Wang, Huan; He, Pinjing

    2014-12-01

    Pyrolysis has been examined as an attractive alternative to incineration for municipal solid waste (MSW) disposal that allows energy and resource recovery; however, it has seldom been applied independently with the output of pyrolysis products as end products. This review addresses the state-of-the-art of MSW pyrolysis in regards to its technologies and reactors, products and environmental impacts. In this review, first, the influence of important operating parameters such as final temperature, heating rate (HR) and residence time in the reaction zone on the pyrolysis behaviours and products is reviewed; then the pyrolysis technologies and reactors adopted in literatures and scale-up plants are evaluated. Third, the yields and main properties of the pyrolytic products from individual MSW components, refuse-derived fuel (RDF) made from MSW, and MSW are summarised. In the fourth section, in addition to emissions from pyrolysis processes, such as HCl, SO2 and NH3, contaminants in the products, including PCDD/F and heavy metals, are also reviewed, and available measures for improving the environmental impacts of pyrolysis are surveyed. It can be concluded that the single pyrolysis process is an effective waste-to-energy convertor but is not a guaranteed clean solution for MSW disposal. Based on this information, the prospects of applying pyrolysis technologies to dealing with MSW are evaluated and suggested. PMID:25256662

  16. Pyrolysis of cellulose and lignin

    International Nuclear Information System (INIS)

    X-ray and UV-induced photoelectron spectroscopy (XPS and UPS) and scanning electron microscopy (SEM) have been performed to characterise the pyrolysis of cellulose and lignin and their interaction with methanol. Clean highly oriented pyrolitic graphite (HOPG) was also analysed as a reference material. Asymmetric C1s core level fits and valence band XPS of the samples indicate a graphitic-like structure after the pyrolysis at 1200 deg. C. Due to the low polar contents in pyrolysed cellulose and lignin, an interaction with methanol under high vacuum conditions could not be identified. From a technical viewpoint a temperature of 1200 deg. C is attainable without high costs. Therefore, the pyrolysis of wood-based polymers containing high amounts of cellulose and lignin are potential low-cost materials for various applications. If it is possible to generate graphite in complex structures made of wood-based polymers, a cheap and energy-efficient method will become available for producing bipolar plates for fuel cells. Technical problems like form instability and foaming are discussed as well as further development and possible modifications of the ground material to achieve optimal compositions.

  17. Gas chromatography mass spectrometric quantitative determination of product distribution of paper pyrolysis with solid acids at low temperature

    International Nuclear Information System (INIS)

    Paper was pyrolyzed at low temperature (300 degree C) both in the absence and presence of catalysts. The liquid products were collected and characterized by using GC/MS. Boric acid and aluminum sulphate acting as catalysts were found to alter the relative concentration and nature of the product due to depolymerizing, polarizing and free radical stabilizing properties. Boric acid was found to decrease the amount of anhydro sugars and favors the formation of esters, ketones and carboxylic acids. Aluminum sulphate favored the formation of furan carboxaldehyde, phenols and other cyclic compounds The cracking of paper and formation of new compounds was facilitated by vacant orbital of the catalyst. Therefore change in concentration of catalyst also changed the nature and concentration of the products. These observations are explained on the basis of the chemical nature of these compounds in this paper. (author)

  18. ISOTHERMAL PYROLYSIS OF KRAFT PULP MILL SLUDGE

    Directory of Open Access Journals (Sweden)

    Syamsudin Syamsudin

    2014-12-01

    Full Text Available Kraft pulp mill sludge cake composed of rejected wood fibers and activated sludge microorganisms. With a heating value about 14 MJ/kg (dried basis, this type of biomass had a potential as an alternative energy source. Unfortunately, it had an ash content of 27.6% and a moisture content of 80%. For reducing moisture content with minimum energy consumption, a combination of mechanical dewatering and thermal drying was studied previously. Meanwhile, experiments on isothermal pyrolysis had been carried out for further improvement on ultimate and proximate analysis of solid fuel. Final mass of char obtained from pyrolysis at 500oC was not significantly different from that of 700oC, so pyrolysis was considered to be optimum at 500oC. A char obtained from pyrolysis at temperature of 500oC had a pore surface area of 77.049 m2/g (highest among other temperatures. Kinetic of isothermal pyrolysis was well represented with a first order modified volumetric model with a frequency factor of 0.782 1/s and an activation of 34.050 kJ/mol.

  19. CATALYTIC THERMAL DECOMPOSITION OF POLYETHYLENE BY PYROLYSIS GAS CHROMATOGRAPHY

    OpenAIRE

    JAN NISAR; MUKHTIAR ALI; IFTIKHAR AHMAD AWAN

    2011-01-01

    An experimental study of the thermal decomposition of polyethylene in an inert atmosphere has been carried out in the temperature range 300-800°C using Shimadzu PYR-2A pyrolyzer for heating the sample. The method allows the accurate control and measurement of the pyrolysis temperature. The production of hydrocarbons and the corresponding monomers of these polymeric systems were monitored. The effects of variation of temperature, sample size, pyrolysis atmosphere, residence time and catalyst o...

  20. Comparative study on pyrolysis of lignocellulosic and algal biomass using a thermogravimetric and a fixed-bed reactor.

    Science.gov (United States)

    Yuan, Ting; Tahmasebi, Arash; Yu, Jianglong

    2014-10-28

    Pyrolysis characteristics of four algal and lignocellulosic biomass samples were studied by using a thermogravimetric analyzer (TGA) and a fixed-bed reactor. The effects of pyrolysis temperature and biomass type on the yield and composition of pyrolysis products were investigated. The average activation energy for pyrolysis of biomass samples by FWO and KAS methods in this study were in the range of 211.09-291.19kJ/mol. CO2 was the main gas component in the early stage of pyrolysis, whereas H2 and CH4 concentrations increased with increasing pyrolysis temperature. Bio-oil from Chlorellavulgaris showed higher content of nitrogen containing compounds compared to lignocellulosic biomass. The concentration of aromatic organic compounds such as phenol and its derivatives were increased with increasing pyrolysis temperature up to 700°C. FTIR analysis results showed that with increasing pyrolysis temperature, the concentration of OH, CH, CO, OCH3, and CO functional groups in char decreased sharply. PMID:25459840

  1. Tissue deoxygenation kinetics induced by prolonged hypoxic exposure in healthy humans at rest.

    Science.gov (United States)

    Rupp, Thomas; Leti, Thomas; Jubeau, Marc; Millet, Guillaume Y; Bricout, Veronique A; Levy, Patrick; Wuyam, Bernard; Perrey, Stephane; Verges, Samuel

    2013-09-01

    This study aimed to investigate the effects of sustained hypoxic exposure on cerebral and muscle oxygenation and cardiorespiratory function at rest. Eleven healthy subjects inhaled a normobaric hypoxic (FiO2=0.12) or normoxic (FiO2=0.21) gas mixture for 4 h at rest, on two separated blinded sessions. Arterial oxygen saturation (SpO2), heart rate variability (HRV), end-tidal CO2 (EtCO2), and oxygenation of quadriceps muscle, prefrontal and motor cortices assessed by near-infrared spectroscopy (NIRS) were measured continuously during each session. Acute mountain sickness symptoms were evaluated at the end of each session. During a hypoxic session, SpO2 reduction (?13%) plateaued after 20 min, while deoxygenation pattern took 30 to 40 min at the cerebral sites to plateau (+5.3±1.6???Mol of deoxygenated-hemoglobin). Deoxygenation was more pronounced in the cerebral cortex compared to the muscle (+2.1±2.3???Mol of deoxygenated-hemoglobin), and NIRS-derived tissue perfusion index showed distinct profiles between the muscle (hypoperfusion) and the brain (hyperperfusion) with prolonged hypoxia. Changes in tissue oxygenation were not associated with cardiorespiratory responses (e.g., HRV, EtCO2) and altitude sickness symptom appearance during hypoxic sessions. These data demonstrate that sustained hypoxia elicits time delay in changes between arterial and tissue (especially cerebral) oxygenation, as well as a tissue-specific sensitivity. PMID:24064948

  2. Deoxygenation of Vegetable Oils over Sulfided Ni, Mo and NiMo Catalysts.

    Czech Academy of Sciences Publication Activity Database

    Kubi?ka, D.; Kaluža, Lud?k

    2010-01-01

    Ro?. 372, ?. 2 (2010), s. 199-208. ISSN 0926-860X R&D Projects: GA MPO FT-TA3/074 Institutional research plan: CEZ:AV0Z40720504 Keywords : deoxygenation * hydrodeoxygenation * biofuels Subject RIV: CC - Organic Chemistry Impact factor: 3.383, year: 2010

  3. Influence of gemfibrozil on sulfate transport in human erythrocytes during the oxygenation-deoxygenation cycle.

    Czech Academy of Sciences Publication Activity Database

    Tellone, E.; Ficarra, S.; Scatena, R.; Giardina, B.; Kotyk, Arnošt; Russo, A.; Colucci, D.; Bellocco, E.; Lagana, G.; Galtieri, A.

    2008-01-01

    Ro?. 57, ?. 4 (2008), s. 621-629. ISSN 0862-8408 R&D Projects: GA AV ?R(CZ) 1ET400110403 Institutional research plan: CEZ:AV0Z50110509 Keywords : gemfibrozil * sulfate transport * oxygenation-deoxygenation Subject RIV: CE - Biochemistry Impact factor: 1.653, year: 2008

  4. FAST PYROLYSIS OF LIGNINS

    OpenAIRE

    Sedat Beis; Saikrishna Mukkamala; Nathan Hill; Jincy Joseph; Cirila Baker; Bruce Jensen; Elizabeth Stemmler; Clayton Wheeler; Brian Frederick; Adriaan van Heiningen; Alex Berg; William Joseph DeSisto

    2010-01-01

    Three lignins: Indulin AT, LignoboostTM, and Acetocell lignin, were characterized and pyrolyzed in a continuous-fed fast pyrolysis process. The physical and chemical properties of the lignins included chemical composition, heat content, ash, and water content. The distributed activation energy model (DAEM) was used to describe the pyrolysis of each lignin. Activation energy distributions of each lignin were quite different and generally covered a broad range of energies, typically found in li...

  5. Catalytic Pyrolysis and a Pyrolysis Kinetic Study of Shredded Printed Circuit Board for Fuel Recovery

    Directory of Open Access Journals (Sweden)

    Salmiaton Ali

    2014-10-01

    Full Text Available Scrap printed circuit boards (PCBs are the most abundant wastes that can be found in the landfills in Malaysia and this disposal certainly poses serious detrimental to the environment. This research aims to investigate optimum temperature for pyrolyzing waste PCBs, find out the best catalyst to be used in accelerating PCBs’ pyrolysis, select suitable ratio of catalyst to PCBs for higher oil yield and examine kinetics pyrolysis of the waste PCBs’ decomposition. Operating temperatures ranged from 200 to 350 ?C of PCB’s pyrolysis were conducted with the optimum temperature obtained was 275 ?C. Fluid cata-lytic cracking (FCC catalyst, zeolite socony mobil-5 (ZSM-5, H-Y-type zeolite and dolomite were used to accelerate PCB’s pyrolysis at 275 ?C and FCC was identified as the best catalyst to be used. Differ-ent ratios of FCC to waste PCBs such as 10:90, 20:80, 30:70, 40:60 and 50:50 were applied in the pyro-lysis at 275 ?C and ratio of 10:90 was selected as the suitable ratio to be utilized for maximum yield. The kinetic study was done through thermogravimetric analysis on waste PCBs under various heating rates and different particle sizes. The GC-MS analysis revealed that compounds detected in the pyro-oil have the potential to be used as fuel. © 2014 BCREC UNDIP. All rights reservedReceived: 23rd July 2014; Revised: 14th August 2014; Accepted: 14th August 2014 How to Cite: Ng, C.H., Salmiaton, A., Hizam, H. (2014. Catalytic Pyrolysis and a Pyrolysis Kinetic Study of Shredded Printed Circuit Board for Fuel Recovery. Bulletin of Chemical Reaction Engineering & Catalysis, 9 (3: 224-240. (doi:10.9767/bcrec.9.3.7148.224-240 Permalink/DOI: http://dx.doi.org/10.9767/bcrec.9.3.7148.224-240

  6. Microwave-assisted pyrolysis of biomass for liquid biofuels production

    DEFF Research Database (Denmark)

    Yin, Chungen

    2012-01-01

    Production of 2nd-generation biofuels from biomass residues and waste feedstock is gaining great concerns worldwide. Pyrolysis, a thermochemical conversion process involving rapid heating of feedstock under oxygen-absent condition to moderate temperature and rapid quenching of intermediate products, is an attractive way for bio-oil production. Various efforts have been made to improve pyrolysis process towards higher yield and quality of liquid biofuels and better energy efficiency. Microwave-assisted pyrolysis is one of the promising attempts, mainly due to efficient heating of feedstock by ‘‘microwave dielectric heating’’ effects. This paper presents a state-of-the-art review of microwave-assisted pyrolysis of biomass. First, conventional fast pyrolysis and microwave dielectric heating is briefly introduced. Then microwave-assisted pyrolysis process is thoroughly discussed stepwise from biomass pretreatment to bio-oil collection. The existing efforts are summarized in a table, providing a handy overview of the activities (e.g., feedstock and pretreatment, reactor/pyrolysis conditions) and findings (e.g., pyrolysis products) of various investigations.

  7. Production, characterization and reactivity studies of chars produced by the isothermal pyrolysis of flax straw

    International Nuclear Information System (INIS)

    The influence of pyrolysis temperature and residence time on the char yields and resultant char characteristics were investigated in the isothermal pyrolysis of flax straw. The pyrolysis temperature was varied in the range between 300 and 500 °C and reaction residence time was varied from 15 to 60 min. The char yield was found to decrease with both increasing pyrolysis temperature and residence time. The char structure and physical characteristics were thoroughly investigated by means of X-ray diffraction (XRD), temperature-programmed oxidation (TPO) and N2 physisorption techniques. The results show that the degree of porosity and graphitization increased with increasing pyrolysis temperature and time. TPO studies on the char samples corroborate well with the XRD findings and showed the presence of two types of carbon; namely, amorphous filamentous carbon and crystalline graphitic carbon. Thermogravimetric analysis (TGA) of the char was performed to understand the combustion kinetics and reactivity. Chars formed at lower pyrolysis temperatures were found to be more reactive than the chars produced at higher pyrolysis temperatures, and these findings are well supported by the TPO, TGA, N2 physisorption and XRD characterization data. Furthermore, an empirical global kinetic model was devised based on power law and used to estimate the activation energy and other kinetic parameters of both flax straw pyrolysis and char combustion processes. -- Highlights: ? The results show conditions to obtain reactive chars from pyrolysis of flax straw. ? A higher pyrolysis temperature leads to a higher amount of nonreactive chars. ? A longer reaction time leads to a higher amount of nonreactive chars. ? A lower pyrolysis temperature and a shorter residence time lead to reactive chars. ? Pyrolysis temperature has a stronger effect on char reactivity than residence time.

  8. Pyrolysis of scrap tyres with zeolite USY

    International Nuclear Information System (INIS)

    A zeolite catalyst of ultrastable Y-type (USY) was investigated in the research of two staged pyrolysis-catalysis of scrap tyres. Scrap tyres were pyrolysed in a fixed bed reactor and the evolved pyrolysis gases were passed through a secondary catalytic reactor. The main objective of this paper was to investigate the effect of zeolite USY on the yield of products and the composition of derived oil. The influences of several parameters such as pyrolysis temperature, catalytic temperature, catalyst/tyre ratio, heating rate, etc. on the yield of the derived oil, char and gas were investigated. It showed that the increase of catalytic temperature and catalyst/tyre ratio resulted in high yield of gas at the expense of the oil yield. For example, when the catalyst/tyre ratio increased from 0.25 to 1.0, the yield of gas increased from 30.5 to 49.9 wt.%, and the oil yield decreased nearly two-fold from 31.6 to 12.7 wt.%. The concentration of light naphtha (boiling point < 160 deg. C) was also investigated in this study. And the high catalyst/tyre ratio favored to increase the concentration of light naphtha (<160 deg. C) in oil. In order to study the composition of derived oil, a distilled fraction (<280 deg. C), which was 92.5 wt.% of the oil obtained from catalytic pyrolysis of scrap tyre at a pyrolysis temperature, catalytic temperature and catalyst/tyre ratio of 500, 400 deg. C and 0.5, respectively, was analyzed with gas chromatography/mass spectrometry (GC/MS). The distiraphy/mass spectrometry (GC/MS). The distillate was found to contain 1.23 wt.% benzene, 9.35 wt.% toluene, 3.68 wt.% ethylbenzene, 12.64 wt.% xylenes, 1.81 wt.% limonene and 13.89 wt.% PAHs, etc., where the single ring aromatics represented a significant potential use as chemicals

  9. Electrocatalytic upgrading of biomass pyrolysis oils to chemical and fuel

    Science.gov (United States)

    Lam, Chun Ho

    The present project's aim is to liquefy biomass through fast pyrolysis and then upgrade the resulting "bio-oil" to renewable fuels and chemicals by intensifying its energy content using electricity. This choice reflects three points: (a) Liquid hydrocarbons are and will long be the most practical fuels and chemical feedstocks because of their energy density (both mass and volume basis), their stability and relative ease of handling, and the well-established infrastructure for their processing, distribution and use; (b) In the U.S., the total carbon content of annually harvestable, non-food biomass is significantly less than that in a year's petroleum usage, so retention of plant-captured carbon is a priority; and (c) Modern technologies for conversion of sunlight into usable energy forms---specifically, electrical power---are already an order of magnitude more efficient than plants are at storing solar energy in chemical form. Biomass fast pyrolysis (BFP) generates flammable gases, char, and "bio-oil", a viscous, corrosive, and highly oxygenated liquid consisting of large amounts of acetic acid and water together with hundreds of other organic compounds. With essentially the same energy density as biomass and a tendency to polymerize, this material cannot practically be stored or transported long distances. It must be upgraded by dehydration, deoxygenation, and hydrogenation to make it both chemically and energetically compatible with modern vehicles and fuels. Thus, this project seeks to develop low cost, general, scalable, robust electrocatalytic methods for reduction of bio-oil into fuels and chemicals.

  10. Preparation of solid nickel nanoparticles by large-scale spray pyrolysis of Ni(NO3)2.6H2O precursor: Effect of temperature and nickel acetate on the particle morphology

    International Nuclear Information System (INIS)

    Spherical nickel nanoparticles were prepared by a large-scale spray pyrolysis process with two continuous reactors and were investigated in terms of particle-formation mechanism, surface property, particle shape, and size with changing the temperature of two continuous reactors and the type of precursor. When nickel nitrate was used as a precursor and the second reactor temperature was over 1200 deg. C, solid Ni particles were obtained, but many ultra-fine particles of less than tens nanometer were simultaneously formed via a gas-to-particle conversion mechanism. The formation of such ultra-fine particles was reduced by making hollow particles in the first reactor at 500 deg. C and thereafter densifying them in the second reactor at 1400 deg. C, but could not completely prevent. The addition of about 5-10 mol% nickel acetate instead nitrate precursor was found to be very effective to avoid the formation of such ultra-fine particles as well as producing solid particles with clean and smooth surface. On the basis of the results obtained, a mechanism of particle formation in the large-scale spray pyrolysis was proposed. Finally, spherical and solid nickel nanoparticles, which had clean surface and high density (larger than 8.4 g/cm3), were prepared from the mixed precursor (nitrate/acetate) at a residence time of about 3 s without any chemical additive

  11. Preconversion catalytic deoxygenation of phenolic functional groups. Quarterly technial progress report, January 1, 1992--March 31, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Kubiak, C.P.

    1992-08-01

    The deoxygenation of phenols is a conceptually simple, but unusually difficult chemical transformation to achieve. The phenolic C-O bond energy of 103 kcal/mol is as strong as a benzene C-H bond and over 10 kcal/mol stronger than the C-O bonds of methanol and ethanol. The consequence of this is that the hydrogenation/deoxygenation methods in current use require severe conditions and give low selectivities. The ongoing research described herein is based on the unprecedented, but thermodynamically promising, use of carbon monoxide as the oxygen atom acceptor for the catalytic deoxygenation of phenols.

  12. Preconversion catalytic deoxygenation of phenolic functional groups. Quarterly technical progress report, January 1, 1992--March 31, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Kubiak, C.P.

    1992-08-01

    The deoxygenation of phenols is a conceptually simple, but unusually difficult chemical transformation to achieve. The phenolic C-O bond energy of 103 kcal/mol is as strong as a benzene C-H bond and over a 10 kcal/mol stronger than the C-O bonds of methanol and ethanol. The consequence of this is that the hydrogenation/deoxygenation methods in current use require severe conditions and give low selectivities. The ongoing research described herein is based on the unprecedented, but thermodynamically promising, use of carbon monoxide as the oxygen atom acceptor for the catalytic deoxygenation of phenols.

  13. Scintillation decay time and pulse shape discrimination in oxygenated and deoxygenated solutions of linear alkylbenzene for the SNO+ experiment

    International Nuclear Information System (INIS)

    The SNO+ liquid scintillator experiment is under construction in the SNOLAB facility in Canada. The success of this experiment relies upon accurate characterization of the liquid scintillator, linear alkylbenzene (LAB). In this paper, scintillation decay times for alpha and electron excitations in LAB with 2 g/L PPO are presented for both oxygenated and deoxygenated solutions. While deoxygenation is expected to improve pulse shape discrimination in liquid scintillators, it is not commonly demonstrated in the literature. This paper shows that for linear alkylbenzene, deoxygenation improves discrimination between electron and alpha excitations in the scintillator.

  14. CATALYTIC THERMAL DECOMPOSITION OF POLYETHYLENE BY PYROLYSIS GAS CHROMATOGRAPHY

    Directory of Open Access Journals (Sweden)

    JAN NISAR

    2011-01-01

    Full Text Available An experimental study of the thermal decomposition of polyethylene in an inert atmosphere has been carried out in the temperature range 300-800°C using Shimadzu PYR-2A pyrolyzer for heating the sample. The method allows the accurate control and measurement of the pyrolysis temperature. The production of hydrocarbons and the corresponding monomers of these polymeric systems were monitored. The effects of variation of temperature, sample size, pyrolysis atmosphere, residence time and catalyst on the distribution of these products were studied. As the carrier gas rapidly swept the primary products from the hot zone into the chromatographic column, so the secondary decomposition is largely eliminated and the pyrolysis products give accurate information about the nature, composition and structure of the pyrolysis material.

  15. CATALYTIC THERMAL DECOMPOSITION OF POLYETHYLENE BY PYROLYSIS GAS CHROMATOGRAPHY

    Scientific Electronic Library Online (English)

    JAN, NISAR; MUKHTIAR, ALI; IFTIKHAR, AHMAD AWAN.

    Full Text Available An experimental study of the thermal decomposition of polyethylene in an inert atmosphere has been carried out in the temperature range 300-800°C using Shimadzu PYR-2A pyrolyzer for heating the sample. The method allows the accurate control and measurement of the pyrolysis temperature. The productio [...] n of hydrocarbons and the corresponding monomers of these polymeric systems were monitored. The effects of variation of temperature, sample size, pyrolysis atmosphere, residence time and catalyst on the distribution of these products were studied. As the carrier gas rapidly swept the primary products from the hot zone into the chromatographic column, so the secondary decomposition is largely eliminated and the pyrolysis products give accurate information about the nature, composition and structure of the pyrolysis material.

  16. Microwave-assisted pyrolysis of methyl ricinoleate for continuous production of undecylenic acid methyl ester (UAME).

    Science.gov (United States)

    Nie, Yong; Duan, Ying; Gong, Ruchao; Yu, Shangzhi; Lu, Meizhen; Yu, Fengwen; Ji, Jianbing

    2015-06-01

    Undecylenic acid methyl ester (UAME) was continuously produced from methyl ricinoleate using a microwave-assisted pyrolysis system with atomization feeding. The UAME yield of 77wt.% was obtained at 500°C using SiC as the microwave absorbent and heating medium. The methyl ricinoleate conversion and UAME yield from microwave-assisted pyrolysis process were higher than those from conventional pyrolysis. The effect of temperature on the pyrolysis process was also investigated. The methyl ricinoleate conversion increased but the cracking liquid yield decreased when the temperature increased from 460°C to 560°C. The maximum UAME yield was obtained at the temperature of 500°C. PMID:25818921

  17. Vacuum pyrolysis of swine manure : biochar production and characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Verma, M. [Inst. de recherche et de developpement en agroenvironnement Inc., Quebec City, PQ (Canada); Centre de recherche industrielle du Quebec, Quebec City, PQ (Canada); Godbout, S.; Larouche, J.P.; Lemay, S.P.; Pelletier, F. [Inst. de recherche et de developpement en agroenvironnement Inc., Quebec City, PQ (Canada); Solomatnikova, O. [Centre de recherche industrielle du Quebec, Quebec City, PQ (Canada); Brar, S.K. [Inst. national de la recherche scientifique, eau, terre et environnement, Quebec City, PQ (Canada)

    2010-07-01

    Quebec accounts for nearly 25 per cent of swine production in Canada. The issue of swine manure is addressed through land spreading and conversion into fertilizer. However, current regulations restrict the use of swine manure as fertilizer on most farmlands due to the problem of surplus phosphorus and nitrogen. Although many technologies exist to separate phosphorus and nitrogen from the organic-rich dry matter in swine manure, about 40 per cent of the treated waste matter must still be disposed in an environmentally sound manner. This study investigated the technical feasibility of pretreating the swine manure solids into biofuels on a farm-scale basis using vacuum pyrolysis process. A custom built stainless steel pressure vessel was used to carry out pyrolysis reaction of swine manure biomass at a temperature range between 200 to 600 degrees C under vacuum. The pyrolytic vapour was condensed in 2 glass condensers in series. The biochar was collected directly from the pyrolysis vessel following completion of the pyrolysis batch. The non condensable vapour and gases were considered as losses. Biochar, bio-oil, an aqueous phase and a gas mixture were the 4 products of the pyrolysis process. A thermogravimetric analysis of the swine manure samples was conducted before the pyrolysis tests. The study showed that 238 degrees C is the optimal pyrolysis temperature for biochar production.

  18. Accuracy and Potential Use of a Developed CFD-pyrolysis Model for Simulating Lab-scale Bio Oil Production

    OpenAIRE

    Mellin, Pelle; Zhang, Qinglin; Kantarelis, Efthymios; Zhou, Chunguang; YANG, WEIHONG

    2012-01-01

    The paper describes development of a CFD¬pyrolysis model using an Eularian-Eularian framework with an implemented pyrolysis reaction model. The CFD¬pyrolysis model is used to simulate the bubbling fluidized bed reactor integrated in a new experimental fast pyrolysis process for bio oil production. The model is compared to experiments in aspect of outlet gas composition, temperature and bed height. Tar behavior and yield of bio oil are illustrated and a parametric study investigates impact of ...

  19. PYROLYSIS AND COMBUSTION OF SCRAP TIRE

    Directory of Open Access Journals (Sweden)

    ?. Jelemenský

    2006-02-01

    Full Text Available In this paper a literature review of both pyrolysis and combustion processes of scrap tires is presented. The work reports, the characteristics of materials, methods, effect of various process parameters, kinetic modelling applied to the pyrolysis and combustion of tires, characteristics of the products and emissions. From the published works results that scrap tire rubber consists of about 60 wt.% volatile organics, 30 wt.% fixed carbon and 10 wt.% ash. Elemental analysis shows that tire rubber contains approximately 80 wt.% of C, 7 wt. of H, 0.4 wt.% of N, 1.5 wt.% of S, 3 wt.% of O and 8 wt.% of ash. Thermogravimetry analysis reveals that the pyrolysis of tire rubber at atmospheric pressure starts at a temperature around 250oC and finishes at a temperature of about 550oC. Generally, more than one degradation temperature region during rubber pyrolysis is recorded. In general, by pyrolysing waste tire three fractions are obtained: solid residue (around 40 wt.%, liquid fraction (around 50 wt.% and gas fraction (around 10 wt.%. The influence of the process conditions on the amount and characteristics of individual fractions was studied by the authors only partially. The general trend is an increase in yields of liquid and gas fractions as the temperature increases. From the works devoted to tire pyrolysis, which are focussed on the generation of liquid fuel results that derived liquids are a complex mixture of organic compounds containing a lot of aromatics. This liquid can be separated into light and higher fractions. The main components of pyrolysis gases reported by various authors are as: H2, H2S, CO, CO2, CH4, C2H4, C3H6 and other light hydrocarbons. The solid residue contains carbon black, and inorganic matter. The results of kinetic modelling of scrap tire pyrolysis and combustion show large differences in the values of kinetic parameters obtained by different authors. As main pollutants from the combustion of waste tires are reported: SO2, NOx, CO and PAHs.

  20. Flash pyrolysis of jatropha oil cake in electrically heated fluidized bed reactor

    International Nuclear Information System (INIS)

    Fluidized bed flash pyrolysis experiments have been conducted on a sample of jatropha oil cake to determine particularly the effects of particle size, pyrolysis temperature and nitrogen gas flow rate on the pyrolysis yields. The particle size, nitrogen gas flow rate and temperature of jatropha oil cake were varied from 0.3 to 1.18 mm, 1.25 to 2.4 m3/h and 350 to 550 oC. The maximum oil yield of 64.25 wt% was obtained at a nitrogen gas flow rate of 1.75 m3/h, particle size of 0.7-1.0 mm and pyrolysis temperature of 500 oC. The calorific value of pyrolysis oil was found to be 19.66 MJ/kg. The pyrolysis gas can be used as a gaseous fuel.

  1. Pyrolysis and Gasification

    DEFF Research Database (Denmark)

    Astrup, Thomas; Bilitewski, B.

    2011-01-01

    Pyrolysis and gasification include processes that thermally convert carbonaceous materials into products such as gas, char, coke, ash, and tar. Overall, pyrolysis generates products like gas, tar, and char, while gasification converts the carboncontaining materials (e.g. the outputs from pyrolysis) into a mainly gaseous output. The specific output composition and relative amounts of the outputs greatly depend on the input fuel and the overall process configuration. Although pyrolysis processes in many cases also occur in gasification (however prior to the gasification processes), the overall technology may often be described as gasification only. Pyrolysis, however, can also be employed without proceeding with gasification. Gasification is by no means a novel process; in the 19th century so-called ‘town gas’ was produced by the gasification of coal and for example used for illumination purposes. In Europe during World War II, wood-fueled gasifiers (or ‘gas generators’) were used to power cars during shortagesof oil-based fuels. Sparked by oil price crises in 1970s and 1980s, further development in gasification technologies focused mainly on coal as a fuel to substitute for oil-based products. Today gasification is used within a range of applications, the most important of which are conversion of coal into syngas for use as chemical feedstock or energy production; but also gasification of biomass and waste is gaining significant interest as emerging technologies for sustainable energy. From a waste management perspective, pyrolysis and gasification are of relatively little importance as an overall management option. Today, gasification is primarily used on specific waste fractions as opposed to mixed household wastes. The main commercial activity so far has been in Japan, with only limited success in Europe and North America (Klein et al., 2004). However, pyrolysis and gasification of waste are generally expected to become more widely used in the future. A main reason for this is that public perceptions of waste incineration in some countries is a major obstacle for installing new incineration capacity, but also a better ability of gasification over incineration to preserve the chemical energy of the waste is important. This chapter provides an overview of pyrolysis and gasification processes related to waste, the technology involved, energy recovery options, and important environmental aspects.

  2. Gold Nanoparticle-Catalyzed Environmentally Benign Deoxygenation of Epoxides to Alkenes

    Directory of Open Access Journals (Sweden)

    Kiyotomi Kaneda

    2011-09-01

    Full Text Available We have developed a highly efficient and green catalytic deoxygenation of epoxides to alkenes using gold nanoparticles (NPs supported on hydrotalcite [HT: Mg6Al2CO3(OH16] (Au/HT with alcohols, CO/H2O or H2 as the reducing reagent. Various epoxides were selectively converted to the corresponding alkenes. Among the novel metal NPs on HT, Au/HT was found to exhibit outstanding catalytic activity for the deoxygenation reaction. Moreover, Au/HT can be separated from the reaction mixture and reused with retention of its catalytic activity and selectivity. The high catalytic performance of Au/HT was attributed to the selective formation of Au-hydride species by the cooperative effect between Au NPs and HT.

  3. Thermal analysis of charring materials based on pyrolysis interface model

    Directory of Open Access Journals (Sweden)

    Huang Hai-Ming

    2014-01-01

    Full Text Available Charring thermal protection systems have been used to protect hypersonic vehicles from high heat loads. The pyrolysis of charring materials is a complicated physical and chemical phenomenon. Based on the pyrolysis interface model, a simulating approach for charring ablation has been designed in order to obtain one dimensional transient thermal behavior of homogeneous charring materials in reentry capsules. As the numerical results indicate, the pyrolysis rate and the surface temperature under a given heat flux rise abruptly in the beginning, then reach a plateau, but the temperature at the bottom rises very slowly to prevent the structural materials from being heated seriously. Pyrolysis mechanism can play an important role in thermal protection systems subjected to serious aerodynamic heat.

  4. Vacuum pyrolysis of waste tires with basic additives

    International Nuclear Information System (INIS)

    Granules of waste tires were pyrolyzed under vacuum (3.5-10 kPa) conditions, and the effects of temperature and basic additives (Na2CO3, NaOH) on the properties of pyrolysis were thoroughly investigated. It was obvious that with or without basic additives, pyrolysis oil yield increased gradually to a maximum and subsequently decreased with a temperature increase from 450 deg. C to 600 deg. C, irrespective of the addition of basic additives to the reactor. The addition of NaOH facilitated pyrolysis dramatically, as a maximal pyrolysis oil yield of about 48 wt% was achieved at 550 deg. C without the addition of basic additives, while a maximal pyrolysis oil yield of about 50 wt% was achieved at 480 deg. C by adding 3 wt% (w/w, powder/waste tire granules) of NaOH powder. The composition analysis of pyrolytic naphtha (i.b.p. (initial boiling point) ?205 deg. C) distilled from pyrolysis oil showed that more dl-limonene was obtained with basic additives and the maximal content of dl-limonene in pyrolysis oil was 12.39 wt%, which is a valuable and widely-used fine chemical. However, no improvement in pyrolysis was observed with Na2CO3 addition. Pyrolysis gas was mainly composed of H2, CO, CH4, CO2, C2H4 and C2H6. Pyrolytic char had a surface area comparable to commercial carbon black, but its proportion of ash (above 11.5 wt%) was much higherve 11.5 wt%) was much higher

  5. Slow Pyrolysis of Cassava Wastes for Biochar Production and Characterization

    OpenAIRE

    Nurhidayah Mohamed Noor; Adilah Shariff; Nurhayati Abdullah

    2012-01-01

    Production of biochar from slow pyrolysis of biomass is a promising carbon negative procedure since it removes the net carbon dioxide in the atmosphere and produce recalcitrant carbon suitable for sequestration in soil. Biochar production can vary significantly with the pyrolysis parameter. This study investigated the impact of temperature and heating rate on the yield and properties of biochar derived from cassava plantations residues which are cassava stem (CS) and cassava rhizome (CR). The...

  6. Production of valuable hydrocarbons by flash pyrolysis of oil shale

    Science.gov (United States)

    Steinberg, M.; Fallon, P.T.

    1985-04-01

    A process for the production of gas and liquid hydrocarbons from particulated oil shale by reaction with a pyrolysis gas at a temperature of from about 700/sup 0/C to about 1100/sup 0/C, at a pressure of from about 400 psi to about 600 psi, for a period of about 0.2 second to about 20 seconds. Such a pyrolysis gas includes methane, helium, or hydrogen. 3 figs., 3 tabs.

  7. ENGINEERING BULLETIN: PYROLYSIS TREATMENT

    Science.gov (United States)

    Pyrolysis is formally defined as chemical decomposition induced in organic materials by heat in the absence of oxygen. In practice, it is not possible to achieve a completely oxygen-free atmosphere; actual pyrolytic systems are operated with less than stoichiometric quantities of...

  8. Thiophenic Sulfur Compounds Released During Coal Pyrolysis.

    Science.gov (United States)

    Xing, Mengwen; Kong, Jiao; Dong, Jie; Jiao, Haili; Li, Fan

    2013-06-01

    Thiophenic sulfur compounds are released during coal gasification, carbonization, and combustion. Previous studies indicate that thiophenic sulfur compounds degrade very slowly in the environment, and are more carcinogenic than polycyclic aromatic hydrocarbons and nitrogenous compounds. Therefore, it is very important to study the principle of thiophenic sulfur compounds during coal conversion, in order to control their emission and promote clean coal utilization. To realize this goal and understand the formation mechanism of thiophenic sulfur compounds, this study focused on the release behavior of thiophenic sulfur compounds during coal pyrolysis, which is an important phase for all coal thermal conversion processes. The pyrolyzer (CDS-5250) and gas chromatography-mass spectrometry (Focus GC-DSQII) were used to analyze thiophenic sulfur compounds in situ. Several coals with different coal ranks and sulfur contents were chosen as experimental samples, and thiophenic sulfur compounds of the gas produced during pyrolysis under different temperatures and heating rates were investigated. Levels of benzothiophene and dibenzothiophene were obtained during pyrolysis at temperatures ranging from 200°C to 1300°C, and heating rates ranging from 6°C/ms to 14°C/ms and 6°C/s to 14°C/s. Moreover, the relationship between the total amount of benzothiophene and dibenzothiophene released during coal pyrolysis and the organic sulfur content in coal was also discussed. This study is beneficial for understanding the formation and control of thiophenic sulfur compounds, since it provides a series of significant results that show the impact that operation conditions and organic sulfur content in coal have on the amount and species of thiophenic sulfur compounds produced during coal pyrolysis. PMID:23781126

  9. Fast Pyrolysis of Four Lignins from Different Isolation Processes Using Py-GC/MS

    Directory of Open Access Journals (Sweden)

    Xiaona Lin

    2015-06-01

    Full Text Available Pyrolysis is a promising approach that is being investigated to convert lignin into higher value products including biofuels and phenolic chemicals. In this study, fast pyrolysis of four types of lignin, including milled Amur linden wood lignin (MWL, enzymatic hydrolysis corn stover lignin (EHL, wheat straw alkali lignin (AL and wheat straw sulfonate lignin (SL, were performed using pyrolysis gas-chromatography/mass spectrometry (Py-GC/MS. Thermogravimetric analysis (TGA showed that the four lignins exhibited widely different thermolysis behaviors. The four lignins had similar functional groups according to the FTIR analysis. Syringyl, guaiacyl and p-hydroxyphenylpropane structural units were broken down during pyrolysis. Fast pyrolysis product distributions from the four lignins depended strongly on the lignin origin and isolation process. Phenols were the most abundant pyrolysis products from MWL, EHL and AL. However, SL produced a large number of furan compounds and sulfur compounds originating from kraft pulping. The effects of pyrolysis temperature and time on the product distributions from corn stover EHL were also studied. At 350 °C, EHL pyrolysis mainly produced acids and alcohols, while phenols became the main products at higher temperature. No obvious influence of pyrolysis time was observed on EHL pyrolysis product distributions.

  10. Environmental fatigue behaviors of wrought and cast stainless steels in 310 .deg. C Deoxygenated Water

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Pyung Yeon

    2011-02-15

    Environmental fatigue behaviors of wrought type 316LN stainless steel and cast CF8M stainless steel were investigated. LCF tests were performed at fixed strain rate of 0.04%/s with 0.4%, 0.6%, 0.8%, 1.0% strain amplitudes in 310 .deg. C deoxygenated water environment. In addition, to analyze microstructure effect on fatigue behavior, low cycle fatigue tests in air environment were performed at fixed strain rate of 0.4%/s, 0.04%/s with 0.4%, 0.8% strain amplitudes. It was shown that the low cycle fatigue life of CF8M in a 310 .deg. C deoxygenated water environment was slightly longer than that of 316LN. On the other hand, the low cycle fatigue life of CF8M in a 310 .deg. C air environment was slightly shorter than that of 316LN or was similar with that of 316LN. Through OM observation and phase image analysis, it was confirmed that the ferrite content of CF8M tested in a 310 .deg. C deoxygenated water environment was larger than that of CF8M tested in a 310 .deg. C air environment. It was shown that the ferrite phase fraction of CF8M tested in 310 .deg. C deoxygenated water environment was approximately 26?28% and that of CF8M tested in air environment was approximately 10?12%. The difference of ferrite content in CF8M results in superior tensile properties as higher ferrite content. Furthermore, the difference of ferrite content in CF8M might be the cause of different result of fatigue life between CF8M and 316LN depending on environment. In this study, focused on CF8M having 26?28% ferrite content, to understand the causes of these differences in a 310 .deg. C deoxygenated water environment, fracture surface and crack morphology were observed. And material factors like microstructure, mechanical properties factors like stress behavior during fatigue life, factors by environmentally assisted cracking (EAC) like hydrogen induced cracking (HIC) and chemical compositions of both materials were analyzed. Mainly in a 310 .deg. C deoxygenated water environment, the analysis of fatigue surface was conducted at 1.0% strain amplitude, the analysis of crack sectioned area was conducted at 0.8% strain amplitude. Mainly in air environment, the analysis of fatigue surface was conducted at 0.4% strain amplitude. Through this study and analysis, it was thought that low cycle fatigue crack growth rate of CF8M would be affected by relative contribution of both barrier role of ferrite phase and acceleration role of crack linkage phenomenon or HIC. In low cycle fatigue operating relatively higher stress, it was known that the crack generally tend to avoid and propagate around hard phase. Like the preceding, this test results indicated that the barrier role such as crack avoiding is slightly greater than acceleration role such as crack linkage added HIC mechanism, resulting in slower fatigue crack growth rate by consumption of excess energy, or longer LCF lives in cast CF8M than wrought type 316LN in 310 .deg. C deoxygenated water.

  11. Environmental fatigue behaviors of wrought and cast stainless steels in 310 .deg. C Deoxygenated Water

    International Nuclear Information System (INIS)

    Environmental fatigue behaviors of wrought type 316LN stainless steel and cast CF8M stainless steel were investigated. LCF tests were performed at fixed strain rate of 0.04%/s with 0.4%, 0.6%, 0.8%, 1.0% strain amplitudes in 310 .deg. C deoxygenated water environment. In addition, to analyze microstructure effect on fatigue behavior, low cycle fatigue tests in air environment were performed at fixed strain rate of 0.4%/s, 0.04%/s with 0.4%, 0.8% strain amplitudes. It was shown that the low cycle fatigue life of CF8M in a 310 .deg. C deoxygenated water environment was slightly longer than that of 316LN. On the other hand, the low cycle fatigue life of CF8M in a 310 .deg. C air environment was slightly shorter than that of 316LN or was similar with that of 316LN. Through OM observation and phase image analysis, it was confirmed that the ferrite content of CF8M tested in a 310 .deg. C deoxygenated water environment was larger than that of CF8M tested in a 310 .deg. C air environment. It was shown that the ferrite phase fraction of CF8M tested in 310 .deg. C deoxygenated water environment was approximately 26?28% and that of CF8M tested in air environment was approximately 10?12%. The difference of ferrite content in CF8M results in superior tensile properties as higher ferrite content. Furthermore, the difference of ferrite content in CF8M might be the cause of different result of fatigue life between CF8M and 316LN depending on environment. In this study, focused on CF8M having 26?28% ferrite content, to understand the causes of these differences in a 310 .deg. C deoxygenated water environment, fracture surface and crack morphology were observed. And material factors like microstructure, mechanical properties factors like stress behavior during fatigue life, factors by environmentally assisted cracking (EAC) like hydrogen induced cracking (HIC) and chemical compositions of both materials were analyzed. Mainly in a 310 .deg. C deoxygenated water environment, the analysis of fatigue surface was conducted at 1.0% strain amplitude, the analysis of crack sectioned area was conducted at 0.8% strain amplitude. Mainly in air environment, the analysis of fatigue surface was conducted at 0.4% strain amplitude. Through this study and analysis, it was thought that low cycle fatigue crack growth rate of CF8M would be affected by relative contribution of both barrier role of ferrite phase and acceleration role of crack linkage phenomenon or HIC. In low cycle fatigue operating relatively higher stress, it was known that the crack generally tend to avoid and propagate around hard phase. Like the preceding, this test results indicated that the barrier role such as crack avoiding is slightly greater than acceleration role such as crack linkage added HIC mechanism, resulting in slower fatigue crack growth rate by consumption of excess energy, or longer LCF lives in cast CF8M than wrought type 316LN in 310 .deg. C deoxygenated water

  12. Volatile Analysis by Pyrolysis of Regolith for Planetary Resource Exploration

    Science.gov (United States)

    Glavin, Daniel P.; Malespin, Charles; ten Kate, Inge L.; Getty, Stephanie A.; Holmes, Vincent E.; Mumm, Erik; Franz, Heather B.; Noreiga, Marvin; Dobson, Nick; Southard, Adrian E.; Feng, Steven H.; Kotecki, Carl A.; Dworkin, Jason P.; Swindle, Timothy D.; Bleacher, Jacob E.; Rice, James W.; Mahaffy, Paul R.

    2012-01-01

    The extraction and identification of volatile resources that could be utilized by humans including water, oxygen, noble gases, and hydrocarbons on the Moon, Mars, and small planetary bodies will be critical for future long-term human exploration of these objects. Vacuum pyrolysis at elevated temperatures has been shown to be an efficient way to release volatiles trapped inside solid samples. In order to maximize the extraction of volatiles, including oxygen and noble gases from the breakdown of minerals, a pyrolysis temperature of 1400 C or higher is required, which greatly exceeds the maximum temperatures of current state-of-the-art flight pyrolysis instruments. Here we report on the recent optimization and field testing results of a high temperature pyrolysis oven and sample manipulation system coupled to a mass spectrometer instrument called Volatile Analysis by Pyrolysis of Regolith (VAPoR). VAPoR is capable of heating solid samples under vacuum to temperatures above 1300 C and determining the composition of volatiles released as a function of temperature.

  13. Biomass pyrolysis processes: performance parameters and their influence on biochar system benefits

    OpenAIRE

    Brownsort, Peter A.

    2009-01-01

    This study focuses on performance of biomass pyrolysis processes for use in biochar systems. Objectives are to understand the range of control of such processes and how this affects potential benefits of pyrolysis biochar systems, in particular for climate change mitigation. Slow, intermediate and fast pyrolysis processes are reviewed. Product yield distributions change depending on feedstock composition and preparation, control of temperature and material flows. These allow s...

  14. Copper-carbon nanocomposites prepared by solid-phase pyrolysis of copper phthalocyanine

    International Nuclear Information System (INIS)

    By using solid-phase pyrolysis of copper phthalocyanine we have prepared copper nanoparticles in carbon matrices. The elemental composition, structure and morphology of nanocomposites were investigated by scanning electron microscopy, energy dispersive X-ray microanalysis and X ray diffraction. Depending on the temperature and time of pyrolysis the sizes of copper nanoparticles can be varied from 10 nm to 400 nm. The structure of carbon matrices also strongly depends on the pyrolysis conditions, which allows to synthesize nanocomposites with given properties

  15. Fuel-N Evolution during the Pyrolysis of Industrial Biomass Wastes with High Nitrogen Content

    OpenAIRE

    Kunio Yoshikawa; Guangwen Xu; Hongfang Chen; Yin Wang

    2012-01-01

    In this study, sewage sludge and mycelial waste from antibiotic production were pyrolyzed in a batch scale fixed-bed reactor as examples of two kinds of typical industrial biomass wastes with high nitrogen content. A series of experiments were conducted on the rapid pyrolysis and the slow pyrolysis of these wastes in the temperature range from 500–800 °C to investigate the Fuel-N transformation behavior among pyrolysis products. The results showed that Fuel-N conversion to ...

  16. Effect of Operating Conditions on Product Distributions and Bio-oil Ageing in Biomass Pyrolysis

    OpenAIRE

    Somrang, Yatika

    2012-01-01

    Alternatives to petroleum-derived fuels are receiving significant interest in order to reduce dependence on finite resources of fossil fuels and to lower fossil-derived CO2 emissions. The present study addresses the production of bio-oil from biomass pyrolysis, one of the potential renewable substitutes to petroleum-derived fuels. The first objective of this work was to investigate the effect of pyrolysis operating parameters, i.e. temperature, heating rate and pyrolysis time, ...

  17. Kinetic Study of the Pyrolysis of Waste Printed Circuit Boards Subject to Conventional and Microwave Heating

    OpenAIRE

    Chunyuan Ma; Chao Zhao; Qingluan Ma; Zhen Liu; Wenlong Wang; Jing Sun

    2012-01-01

    This paper describes a kinetic study of the decomposition of waste printed circuit boards (WPCB) under conventional and microwave-induced pyrolysis conditions. We discuss the heating rates and the influence of the pyrolysis on the thermal decomposition kinetics of WPCB. We find that the thermal degradation of WPCB in a controlled conventional thermogravimetric analyzer (TGA) occurred in the temperature range of 300 °C–600 °C, where the main pyrolysis of organic matter takes place along wi...

  18. Pyrolysis of Spent Ion Exchange Resins - 12210

    International Nuclear Information System (INIS)

    Organic ion exchangers (IEX) play a major and increasing role in the reactor coolant and other water purification processes. During their operation time they receive significant amounts of radioactivity, making their disposal, together with their organic nature, as medium active waste challenging. Processes applied so far do not eliminate the organic matter, which is unwanted in disposal facilities, or, if high temperatures are applied, raise problems with volatile radionuclides. NUKEM Technologies offers their well introduces process for the destruction of spent solvent (TBP), the pebble bed pyrolysis, now for the treatment of spent IEX (and other problematic waste), with the following benefits: the pyrolysis product is free of organic matter, and the operation temperature with approx. 500 deg. C keeps Cs radionuclides completely in the solid residue. (authors)

  19. Fast pyrolysis of oil palm shell (OPS)

    Science.gov (United States)

    Abdullah, Nurhayati; Sulaiman, Fauziah; Aliasak, Zalila

    2015-04-01

    Biomass is an important renewable source of energy. Residues that are obtained from harvesting and agricultural products can be utilised as fuel for energy generation by conducting any thermal energy conversion technology. The conversion of biomass to bio oil is one of the prospective alternative energy resources. Therefore, in this study fast pyrolysis of oil palm shell was conducted. The main objective of this study was to find the optimum condition for high yield bio-oil production. The experiment was conducted using fixed-bed fluidizing pyrolysis system. The biomass sample was pyrolysed at variation temperature of 450°C - 650°C and at variation residence time of 0.9s - 1.35s. The results obtained were further discussed in this paper. The basic characteristic of the biomass sample was also presented here. The experiment shows that the optimum bio-oil yield was obtained at temperature of 500°C at residence time 1.15s.

  20. Fixed-bed pyrolysis of rapeseed (Brassica napus L.)

    International Nuclear Information System (INIS)

    Fixed-bed slow and fast pyrolysis experiments have been conducted on a sample of rapeseed. The experiments were performed in two different pyrolysis reactors, namely a fixed-bed Heinze and a well-swept fixed-bed tubular retort to investigate the effects of heating rate, pyrolysis temperature, particle size, sweep gas velocity on the pyrolysis product yields and chemical compositions. The maximum oil yield of 51.7% was obtained in the Heinze reactor 550 deg. C, with a particle size range of +0.6-1.8 mm (sweep gas 100 cm3 min-1 N2) at a heating rate of 30 deg. C min-1. In the well-swept fixed-bed reactor, the maximum oil yield of 68% was obtained at a heating rate of 300 deg. C min-1. Chromatographic and spectroscopic studies on the pyrolytic oil showed that the oil obtained from rapeseed could be use as a renewable fuels and chemical feedstock

  1. Distribution of sulphur into products from waste tire pyrolysis

    International Nuclear Information System (INIS)

    Tire pyrolysis is getting growing attention as an effective waste tire disposal method in comparison to environmentally less friendly methods like dumping or incineration. But the scrap tire sulphur content can be a potential obstacle to scrap tire utilization as a fuel. In this paper the distribution of sulphur into tire pyrolysis yields, solid (char) and liquid (tar), was investigated. The pyrolysis experiments were carried out under different conditions to determine the partitioning of sulphur into pyrolysis products. The influence of different temperatures and reaction times was investigated in a laboratory flow reactor under nitrogen atmosphere. Solid and liquid residues were collected and analyzed by elemental analysis. The sulphur content in residual char and tar was determined using an elemental analyzer and the sulphur forms in tar were characterized by the X-ray photoelectron spectroscopy (XPS). (Authors)

  2. Pyrolysis and gasification behavior of black liquor under pressurized conditions

    Energy Technology Data Exchange (ETDEWEB)

    Whitty, K.

    1997-11-01

    The purpose of this study has been to enhance the understanding of the processes involved in pressurized black liquor gasification. Gasification is known to occur in three stages: drying, pyrolysis and char gasification. The work presented here focuses on the pyrolysis and gasification stages. Experiments were carried out primarily in two laboratory-scale reactors. A pressurized grid heater was used to study black liquor pyrolysis under pressurized conditions. Char yields and the fate of elements in the liquor, as well as the degree of liquor swelling, were measured in this device. A pressurized thermogravimetric reactor was used to measure the rate of the char gasification process under different temperatures and pressures and in various gas atmospheres. Pyrolysis experiments were also carried out in this device, and data on swelling behavior, char yields and component release were obtained 317 refs.

  3. Organic emissions from coal pyrolysis: mutagenic effects.

    OpenAIRE

    Braun, A. G.; Wornat, M. J.; Mitra, A.; Sarofim, A. F.

    1987-01-01

    Four different types of coal have been pyrolyzed in a laminar flow, drop tube furnace in order to establish a relationship between polycyclic aromatic compound (PAC) evolution and mutagenicity. Temperatures of 900K to 1700K and particle residence times up to 0.3 sec were chosen to best simulate conditions of rapid rate pyrolysis in pulverized (44-53 microns) coal combustion. The specific mutagenic activity (i.e., the activity per unit sample weight) of extracts from particulates and volatiles...

  4. A Comparison of Lignin, Macroalgae, Wood and Straw Fast Pyrolysis

    DEFF Research Database (Denmark)

    Trinh, Ngoc Trung; Jensen, Peter Arendt

    2013-01-01

    A fast pyrolysis study on lignin and macroalgae (non-conventional biomass) and wood and straw (conventional biomass) were carried out in a pyrolysis centrifugal reactor at pyrolysis temperature of 550 ºC. The product distributions and energy recoveries were measured and compared among these biomasses. The fast pyrolysis of macroalgae showed a promising result with a bio-oil yield of 65 wt% dry ash free basis (daf) and 76 % energy recovery in the bio-oil while the lignin fast pyrolysis provides a bio-oil yield of 47 wt% daf and energy recovery in bio-oil of 45 %. The physiochemical properties of the bio-oils were characterized with respect to higher heating value (HHV), molecular mass distribution, viscosity, pH, density, thermal behaviors, elemental concentrations, phase separation and aging. The lignin and macroalgae oil properties were different compared to those of the wood and straw oils with respect to carbon and oxygen contents, HHV, thermal behaviors and mean molecular weight. The HHV of wood, straw, lignin and algae oils were 24.0, 23.7, 29.7 and 25.7 MJ/kg db, respectively. The distributions of metals, Cl and S in char and bio-oil were investigated for the biomasses. Almost all the metals (Al, Ca, Fe, K, Mg, Na, P and Si) were contained in the chars at the pyrolysis temperature of 550 ºC. The char properties were characterized and their potential applications are discussed.

  5. Fuel Nitrogen Evolution during Coal Pyrolysis and Gasification

    Science.gov (United States)

    Che, Defu; Liu, Yinhe; Lin, Junguang

    2010-03-01

    The morphology of fuel nitrogen in coal and its fate during pyrolysis and the nitrogen species including N2, HCN and NH3 during coal pyrolysis and gasification have been investigated to clarify the evolution mechanism of fuel nitrogen in heat treatment process. Experimental results show that the morphology of coal nitrogen in the studied Chinese raw coals generally include pyrrolic nitrogen (N-5), pyridinic nitrogen (N-6), quaternary nitrogen (N-Q) and nitrogen-oxide (N-X). Generally, nitrogen in char is transformed to volatile and more stable components during pyrolysis. Char-N is the major source of NOx precursors during temperature programmed pyrolysis in 600-800° C. N-5 and N-X in char is converted to HCN first, and HCN is then hydrogenated to NH3. N-Q in char is the main source of nitrogen gas. The major nitrogenous gas products during rapid coal pyrolysis are N2, HCN and NH3, amongst which N2 is dominant. The yields of N2 and NOx precursors, such as HCN and NH3, increase with increased pyrolysis temperature. The major gaseous nitrogenous products during coal gasification in steam include HCN, NH3 and N2. H2O is the main source of the groups containing hydrogen, which not only participates in the reaction as a gasification agent, but also has catalysis on the reaction.

  6. Olive bagasse (Olea europa L.) pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Sensoz, S.; Demiral, I. [Osmangazi Univ., Eskisehir (Turkey). Dept. of Chemical Engineering; Gercel, H.F. [Anadolu Univ., Eskisehir (Turkey). Dept. of Chemical Engineering

    2006-02-15

    Olive bagasse (Olea europea L.) was pyrolysed in a fixed-bed reactor. The effects of pyrolysis temperature, heating rate, particle size and sweep gas flow rates on the yields of the products were investigated. Pyrolysis runs were performed using pyrolysis temperatures between 350 and 550 {sup o}C with heating rates of 10 and 50 {sup o}C min{sup -} {sup 1}. The particle size and sweep gas flow rate varied in the ranges 0.224-1.8 mm and 50-200 cm{sup 3} min {sup -1}, respectively. The bio-oil obtained at 500 {sup o}C was analysed and at this temperature the liquid product yield was the maximum. The various characteristics of bio-oil obtained under these conditions were identified on the basis of standard test methods. The empirical formula of the bio-oil with heating value of 31.8 MJ kg{sup -1} was established as CH{sub 1.65}O{sub 0.25}N{sub 0.03}. The chemical characterization showed that the bio-oil obtained from olive bagasse may be potentially valuable as a fuel and chemical feedstock. (author)

  7. Quality improvement of pyrolysis oil from waste rubber by adding sawdust.

    Science.gov (United States)

    Wang, Wen-liang; Chang, Jian-min; Cai, Li-ping; Shi, Sheldon Q

    2014-12-01

    This work was aimed at improving the pyrolysis oil quality of waste rubber by adding larch sawdust. Using a 1 kg/h stainless pyrolysis reactor, the contents of sawdust in rubber were gradually increased from 0%, 50%, 100% and 200% (wt%) during the pyrolysis process. Using a thermo-gravimetric (TG) analyzer coupled with Fourier transform infrared (FTIR) analysis of evolving products (TG-FTIR), the weight loss characteristics of the heat under different mixtures of sawdust/rubber were observed. Using the pyrolysis-gas chromatography (GC)-mass spectrometry (Py-GC/MS), the vapors from the pyrolysis processes were collected and the compositions of the vapors were examined. During the pyrolysis process, the recovery of the pyrolysis gas and its composition were measured in-situ at a reaction temperature of 450 °C and a retaining time of 1.2s. The results indicated that the efficiency of pyrolysis was increased and the residual carbon was reduced as the percentage of sawdust increased. The adding of sawdust significantly improved the pyrolysis oil quality by reducing the polycyclic aromatic hydrocarbons (PAHs) and nitrogen and sulfur compounds contents, resulting in an improvement in the combustion efficiency of the pyrolysis oil. PMID:25223439

  8. Thermodynamic analysis for syngas production from volatiles released in waste tire pyrolysis

    International Nuclear Information System (INIS)

    Highlights: • Pyrolysis experiments have been conducted in a continuous auger reactor. • Pyrolysis temperature influence on composition of both volatiles and char was studied. • A process for syngas production has been proposed from the volatiles. • Equivalence ratio down to 0.4 is a practical limit for syngas production. • The results provide essential data prior to perform any experimental campaign. - Abstract: This paper shows the maximum limit on syngas composition obtained from volatiles released in waste tire pyrolysis when they are submitted to an air–steam partial oxidation process. Thus, from mass and energy balances and a stoichiometric equilibrium model, syngas composition and reaction temperature as well as some process parameters were predicted by varying both the equivalence ratio (ER) and the steam to fuel ratio (SF). In addition, pyrolysis experiments were performed using a continuous auger reactor, and the influence of pyrolysis temperature on composition of both volatiles and char was studied. Consequently, the resulting syngas characteristics were correlated with the pyrolysis temperature. The stoichiometric equilibrium model showed that an ER down to 0.4 is a practical limit to perform the air–steam partial oxidation process. When the process is carried out only with air, volatiles obtained at high pyrolysis temperature lead to lower reaction temperature and higher LHV of syngas in comparison with those found at low pyrolysis temperature. The H2 production is favored between 0.20 and 0.40 of ER and seems to be more influenced by the H/C ratio than by the water gas-shift reaction. On the other hand, the steam addition shows a more notable effect on the H2 production for volatiles obtained at the highest pyrolysis temperature (600 °C) in agreement with the lower reaction temperature under these experimental conditions. This thermodynamic analysis provides essential data on the optimization of syngas production from volatiles released in waste tire pyrolysis prior to run any test

  9. Catalytic Deoxygenation of Renewable Chemicals   – Structure?Performance Studies

    DEFF Research Database (Denmark)

    Malcho, Phillip

    2014-01-01

    Generation of chemicals from a viable feedstock is an increasingly interesting field. One of the major issues is the high oxygen ratios in biomass. There are a multitude of ways to remove oxygen from organic molecules. This thesis deals with two topics: The dehydration of glucose into HMF and the decarbonylation of aldehydes both heterogeneous and in ionic liquids. Chapter 1 provides a walkthrough of areas such as green chemistry, ionic liquids, biomass, dehydration of glucose in ionic liquids and decarbonylation. The topics are all taking into account the current research and is subjectively chosen to provide a broad platform for the following chapters. Furthermore, the objectives for the thesis are listed here. Chapter 2 deals with the synthetic preparation of the catalysts and the catalytic setups. Chapter 3 deals with the dehydration of glucose into HMF in ionic liquids. The system was investigated thouroughly via several spectroscopic techniques. This was done in order to obtain novel information in regard to the catalytically active sites. EXAFS results showed that during the catalytic reaction, a species of the form CrCl4O2 was formed from CrCl6 in the solution. These are the predominant chromium containing species in the solution. EPR results showed the presence of a S= 1/2 spin system, and the only possible choice is radical formation. Optical absorption spectroscopy showed a change in the ligand field around the chromium. Chapter 3 also deals with the homogeneous decarbonylation of aldehydes. The investigation of the effects of the ionic liquids in the catalytically active species is investigated in depth and the system [Rh(dppp)2]Cl in BMImCl was shown to be the most active combination. The reusability of the system showed great potential. The system showed a potential to decarbonylate both aliphatic and aromatic aldehydes. Finally Chapter 3 looks at the heterogeneous decarbonylation of aldehydes, focussing on a continuous flow setup. The catalytic effect of oxidation state and ligandsphere is investigated. And the effects of temperature, solvent and substrate were under scrutiny. The catalyst decomposition was pictured by the aid of TEM and the formation of nanoparticles explained. Chapter 4 concerns the summation of the results as well as the future perspectives for the respective applications and scientific developments.

  10. Controlled catalystic and thermal sequential pyrolysis and hydrolysis of polycarbonate and plastic waste to recover monomers

    Science.gov (United States)

    Evans, Robert J. (Lakewood, CO); Chum, Helena L. (Arvada, CO)

    1994-01-01

    A process of using fast pyrolysis to convert a plastic waste feed stream containing polycarbonate and ABS to high value monomeric constituents prior to pyrolysis of other plastic components therein comprising: selecting a first temperature program range to cause pyrolysis of a given polymer to its high value monomeric constituents prior to a temperature range that causes pyrolysis of other plastic components; selecting an acid or base catalysts and an oxide or carbonate support for treating the feed stream to affect acid or base catalyzed reaction pathways to maximize yield or enhance separation of the high value monomeric constituents of polycarbonate and ABS in the first temperature program range; differentially heating the feed stream at a heat rate within the first temperature program range to provide differential pyrolysis for selective recovery of optimum quantities of the high value monomeric constituents prior to pyrolysis or other plastic components; separating the high value monomeric constituents from the polycarbonate to cause pyrolysis to a different high value monomeric constituent of the plastic waste and differentially heating the feed stream at the second higher temperature program range to cause pyrolysis of different high value monomeric constituents; and separating the different high value monomeric constituents.

  11. Controlled catalytic and thermal sequential pyrolysis and hydrolysis of polycarbonate and plastic waste to recover monomers

    Science.gov (United States)

    Evans, R.J.; Chum, H.L.

    1994-06-14

    A process is described using fast pyrolysis to convert a plastic waste feed stream containing polycarbonate and ABS to high value monomeric constituents prior to pyrolysis of other plastic components therein comprising: selecting a first temperature program range to cause pyrolysis of a given polymer to its high value monomeric constituents prior to a temperature range that causes pyrolysis of other plastic components; selecting an acid or base catalysts and an oxide or carbonate support for treating the feed stream to affect acid or base catalyzed reaction pathways to maximize yield or enhance separation of the high value monomeric constituents of polycarbonate and ABS in the first temperature program range; differentially heating the feed stream at a heat rate within the first temperature program range to provide differential pyrolysis for selective recovery of optimum quantities of the high value monomeric constituents prior to pyrolysis or other plastic components; separating the high value monomeric constituents from the polycarbonate to cause pyrolysis to a different high value monomeric constituent of the plastic waste and differentially heating the feed stream at the second higher temperature program range to cause pyrolysis of different high value monomeric constituents; and separating the different high value monomeric constituents. 68 figs.

  12. Synthesis of methyl glycosides of some alpha-isomalto oligosaccharides specifically deoxygenated at position C-2.

    Science.gov (United States)

    Petráková, E; Glaudemans, C P

    1995-03-01

    Methyl alpha-isomaltoside and methyl alpha-isomaltotrioside analogues specifically deoxygenated at position C-2 of various glucopyranosyl units were synthesized by condensation of either 6-O-acetyl-3-O-benzoyl-4-O-benzyl-1-O-tert-butyldimethylsilyl-2-deoxy- beta-D-arabino-hexopyranose (trimethylsilyl triflate mediated) or 6-O-acetyl-2,3,4-tri-O-benzyl-alpha-D-glucopyranosyl chloride (mediated by silver carbonate and silver triflate) with suitably blocked derivatives of methyl alpha-D-glucopyranoside, its 2-deoxy analogue, or methyl 2'-deoxy-alpha-isomaltoside. PMID:7736465

  13. Slow Pyrolysis as a Method for the Destruction of Japanese Wireweed, Sargassum muticum

    Directory of Open Access Journals (Sweden)

    John J Milledge

    2014-12-01

    Full Text Available Japanese wireweed, Sargassum muticum is an invasive species to Great Britain, which might be controlled by harvesting it for energy and chemicals. Pyrolysis is the thermal decomposition of the organic components of dry biomass by heating in the absence of air. The distribution of matter between solid, liquid and syngas depends on the biomass and the pyrolysis temperature and time. Slow pyrolysis with lower temperatures (~ 400 oC tends to produce more solid char. Pyrolysis char can be an effective soil ameliorant, a sequestration agent due to its stability or burned as a fuel. The research attempts to answer the question: Could slow pyrolysis be an energy efficient means for the destruction of Japanese wireweed and produce a potential product, biochar? A simple test rig was developed to establish the yield of biochar, biocrude and syngas from the slow pyrolysis of Sargassum muticum. An energy balance was calculated using compositional data from the analysis of the seaweed feedstock, higher heating values (HHV from bomb-calorimetry and literature values. The energy required to heat 1 kg of dry seaweed by 400 oC for slow pyrolysis was estimated at 0.5 MJ. The HHV of syngas and biocrude produced from the pyrolysis totalled 2.9 MJ. There is, therefore, sufficient energy in the biocrude and syngas fractions produced by the pyrolysis of seaweed to power the process and produce useful biochar, but insufficient energy for drying.

  14. Thermogravimetric analysis and fast pyrolysis of Milkweed.

    Science.gov (United States)

    Kim, Seung-Soo; Agblevor, Foster A

    2014-10-01

    Pyrolysis of Milkweed was carried out in a thermogravimetric analyzer and a bubbling fluidized bed reactor. Total liquid yield of Milkweed pyrolysis was between 40.74% and 44.19 wt% between 425 °C and 550 °C. The gas yield increased from 27.90 wt% to 33.33 wt% with increasing reaction temperature. The higher heating values (HHV) of the Milkweed bio-oil were relatively high (30.33-32.87 MJ/kg) and varied with reaction temperature, feeding rate and fluidization velocity. The selectivity for CO2 was highest within non-condensable gases, and the molar ratio of CO2/CO was about 3 at the different reaction conditions. The (13)C NMR analysis, of the bio-oil showed that the relative concentration carboxylic group and its derivatives was higher at 425 °C than 475 °C, which resulted in slightly higher oxygen content in bio-oil. The pH of aqueous phase obtained at 475 °C was 7.37 which is the highest reported for any lignocellulosic biomass pyrolysis oils. PMID:25064334

  15. UVC emitting phosphors obtained by spray pyrolysis

    International Nuclear Information System (INIS)

    The broadband inter-configurational (4f15d1?4f2) emission of Pr3+ doped in lanthanum orthophosphate (LaPO4) and in calcium pyrophosphate (Ca2P2O7) has been investigated under plasma excitation. The synthesis by spray pyrolysis at moderate temperature followed by a controlled annealing proves to be a very efficient way to produce good quality UVC emitting phosphor Ca1.92Pr0.04Na0.04P2O7 (? phase). The emission of this phosphor in the wavelength range 200-350 nm has been measured with a prototype device, which can be employed for anti-microbial testing. - Research Highlights: ? The Pr3+ doped orthophosphate and pyrophosphate were synthesized by spray pyrolysis. ? The dense particles present good quality UVC emitting (200-350 nm). ? The prototype device can be employed for anti-microbial testing.

  16. Validation Results for Core-Scale Oil Shale Pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Staten, Josh; Tiwari, Pankaj

    2015-03-01

    This report summarizes a study of oil shale pyrolysis at various scales and the subsequent development a model for in situ production of oil from oil shale. Oil shale from the Mahogany zone of the Green River formation was used in all experiments. Pyrolysis experiments were conducted at four scales, powdered samples (100 mesh) and core samples of 0.75”, 1” and 2.5” diameters. The batch, semibatch and continuous flow pyrolysis experiments were designed to study the effect of temperature (300°C to 500°C), heating rate (1°C/min to 10°C/min), pressure (ambient and 500 psig) and size of the sample on product formation. Comprehensive analyses were performed on reactants and products - liquid, gas and spent shale. These experimental studies were designed to understand the relevant coupled phenomena (reaction kinetics, heat transfer, mass transfer, thermodynamics) at multiple scales. A model for oil shale pyrolysis was developed in the COMSOL multiphysics platform. A general kinetic model was integrated with important physical and chemical phenomena that occur during pyrolysis. The secondary reactions of coking and cracking in the product phase were addressed. The multiscale experimental data generated and the models developed provide an understanding of the simultaneous effects of chemical kinetics, and heat and mass transfer on oil quality and yield. The comprehensive data collected in this study will help advance the move to large-scale in situ oil production from the pyrolysis of oil shale.

  17. Kinetics of scrap tyre pyrolysis under vacuum conditions

    International Nuclear Information System (INIS)

    Scrap tyre pyrolysis under vacuum is attractive because it allows easier product condensation and control of composition (gas, liquid and solid). With the aim of determining the effect of vacuum on the pyrolysis kinetics, a study has been carried out in thermobalance. Two data analysis methods have been used in the kinetic study: (i) the treatment of experimental data of weight loss and (ii) the deconvolution of DTG (differential thermogravimetry) curve. The former allows for distinguishing the pyrolysis of the three main components (volatile components, natural rubber and styrene-butadiene rubber) according to three successive steps. The latter method identifies the kinetics for the pyrolysis of individual components by means of DTG curve deconvolution. The effect of vacuum in the process is significant. The values of activation energy for the pyrolysis of individual components of easier devolatilization (volatiles and NR) are lower for pyrolysis under vacuum with a reduction of 12 K in the reaction starting temperature. The kinetic constant at 503 K for devolatilization of volatile additives at 0.25 atm is 1.7 times higher than that at 1 atm, and that corresponding to styrene-butadiene rubber at 723 K is 2.8 times higher. Vacuum enhances the volatilization and internal diffusion of products in the pyrolysis process, which contributes to attenuating the secondary reactions of the repolymerization and carbonization of these products on the surface of the char (carbon oducts on the surface of the char (carbon black). The higher quality of carbon black is interesting for process viability. The large-scale implementation of this process in continuous mode requires a comparison to be made between the economic advantages of using a vacuum and the energy costs, which will be lower when the technologies used for pyrolysis require a lower ratio between reactor volume and scrap tyre flow rate.

  18. Kinetics of scrap tyre pyrolysis under vacuum conditions.

    Science.gov (United States)

    Lopez, Gartzen; Aguado, Roberto; Olazar, Martín; Arabiourrutia, Miriam; Bilbao, Javier

    2009-10-01

    Scrap tyre pyrolysis under vacuum is attractive because it allows easier product condensation and control of composition (gas, liquid and solid). With the aim of determining the effect of vacuum on the pyrolysis kinetics, a study has been carried out in thermobalance. Two data analysis methods have been used in the kinetic study: (i) the treatment of experimental data of weight loss and (ii) the deconvolution of DTG (differential thermogravimetry) curve. The former allows for distinguishing the pyrolysis of the three main components (volatile components, natural rubber and styrene-butadiene rubber) according to three successive steps. The latter method identifies the kinetics for the pyrolysis of individual components by means of DTG curve deconvolution. The effect of vacuum in the process is significant. The values of activation energy for the pyrolysis of individual components of easier devolatilization (volatiles and NR) are lower for pyrolysis under vacuum with a reduction of 12K in the reaction starting temperature. The kinetic constant at 503K for devolatilization of volatile additives at 0.25atm is 1.7 times higher than that at 1atm, and that corresponding to styrene-butadiene rubber at 723K is 2.8 times higher. Vacuum enhances the volatilization and internal diffusion of products in the pyrolysis process, which contributes to attenuating the secondary reactions of the repolymerization and carbonization of these products on the surface of the char (carbon black). The higher quality of carbon black is interesting for process viability. The large-scale implementation of this process in continuous mode requires a comparison to be made between the economic advantages of using a vacuum and the energy costs, which will be lower when the technologies used for pyrolysis require a lower ratio between reactor volume and scrap tyre flow rate. PMID:19589669

  19. Pyrolysis of Softwood Carbohydrates in a Fluidized Bed Reactor

    Science.gov (United States)

    Aho, Atte; Kumar, Narendra; Eränen, Kari; Holmbom, Bjarne; Hupa, Mikko; Salmi, Tapio; Murzin, Dmitry Yu.

    2008-01-01

    In the present work pyrolysis of pure pine wood and softwood carbohydrates, namely cellulose and galactoglucomannan (the major hemicellulose in coniferous wood), was conducted in a batch mode operated fluidized bed reactor. Temperature ramping (5 °C/min) was applied to the heating until a reactor temperature of 460 °C was reached. Thereafter the temperature was kept until the release of non-condensable gases stopped. The different raw materials gave significantly different bio-oils. Levoglucosan was the dominant product in the cellulose pyrolysis oil. Acetic acid was found in the highest concentrations in both the galactoglucomannan and in the pine wood pyrolysis oils. Acetic acid is most likely formed by removal of O-acetyl groups from mannose units present in GGM structure. PMID:19325824

  20. Thermal response of heat-resistant layer with pyrolysis

    Directory of Open Access Journals (Sweden)

    Huang Haiming

    2012-01-01

    Full Text Available A model is developed for analyzing the thermal response of the heat-resistant layer composed of high silica fiber reinforced phenolic matrix composites(SiO2/P and aluminum, in which pyrolysis and phase transitions are exsited, such as melt, vaporization and sublimation. Based on this model, the thermal response of the heat-resistant layer with different SiO2/P thickness is calculated under a heat flux by using FORTRAN codes. As indicated in the results, the slope of temperature gets a sudden decline at the pyrolysis interface, which is due to the latent heat of pyrolysis; the thickness of heat-resistant layer has little influence on the heating-surface temperature, however, the back temperature may increase with the decreasing thickness; and the thermal conductivity of carbonized layer is very important to thermal response.

  1. Pyrolysis of Softwood Carbohydrates in a Fluidized Bed Reactor

    Directory of Open Access Journals (Sweden)

    Dmitry Yu. Murzin

    2008-09-01

    Full Text Available In the present work pyrolysis of pure pine wood and softwood carbohydrates, namely cellulose and galactoglucomannan (the major hemicellulose in coniferous wood, was conducted in a batch mode operated fluidized bed reactor. Temperature ramping (5°C/min was applied to the heating until a reactor temperature of 460 °C was reached. Thereafter the temperature was kept until the release of non-condensable gases stopped. The different raw materials gave significantly different bio-oils. Levoglucosan was the dominant product in the cellulose pyrolysis oil. Acetic acid was found in the highest concentrations in both the galactoglucomannan and in the pine wood pyrolysis oils. Acetic acid is most likely formed by removal of O-acetyl groups from mannose units present in GGM structure.

  2. RATES AND EQUILIBRIA OF DEVOLATILIZATION AND TRACE ELEMENT EVOLUTION IN COAL PYROLYSIS

    Science.gov (United States)

    The report gives results of using a laminar-flow furnace to study the kinetics of devolatilization and evolution of S, As, Pb, and Hg in the pyrolysis of pulverized coal in nitrogen. Variables included pyrolysis time, reactor temperature, and coal type. Devolatilization rates and...

  3. Preparation of YBCO superconducting films by spray pyrolysis method

    International Nuclear Information System (INIS)

    The methodology for the preparation of YBCO superconducting films on Zr2O(Y) substrates by spray pyrolysis method is reported. The transition temperature of these films is superior than the boiling temperature of liquid 2N. Other critical parameters are similar to those reported by other authors using the same technique

  4. Pyrolysis oil as diesel fuel

    Energy Technology Data Exchange (ETDEWEB)

    Gros, S. [Wartsila Diesel International Ltd., Vaasa (Finland). Diesel Technology

    1996-12-31

    Wood waste pyrolysis oil is an attractive fuel alternative for diesel engine operation. The main benefit is the sustainability of the fuel. No fossil reserves are consumed. The fact that wood waste pyrolysis oil does not contribute to CO{sub 2} emissions is of utmost importance. This means that power plants utilising pyrolysis oil do not cause additional global warming. Equally important is the reduced sulphur emissions that this fuel alternative implies. The sulphur content of pyrolysis oil is extremely low. The high water content and low heating value are also expected to result in very low NO{sub x} emissions. Utilisation of wood waste pyrolysis oil in diesel engines, however, involves a lot of challenges and problems to be solved. The low heating value requires a new injection system with high capacity. The corrosive characteristics of the fluid also underline the need for new injection equipment materials. Wood waste pyrolysis oil contains solid particles which can clog filters and cause abrasive wear. Wood waste pyrolysis oil has proven to have extremely bad ignition properties. The development of a reliable injection system which is able to cope with such a fuel involves a lot of optimisation tests, redesign and innovative solutions. Successful single-cylinder tests have already been performed and they have verified that diesel operation on wood pyrolysis oil is technically possible. (orig.)

  5. Microwave Heating Applied to Pyrolysis

    OpenAIRE

    Fernández, Yolanda; Arenillas, Ana; Menéndez, J. Ángel

    2011-01-01

    the MW pyrolysis as an original thermochemical process of materials is presented. This chapter comprises a general overview of the thermochemical and quantifying aspects of the pyrolysis process, including current application togethe with a compilation of the most frequently used materials

  6. Laboratory evaluation of a Pd-based catalyst for deoxygenation of stator cooling water

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Shelton; Rudolph, Andreas [Kinectrics Inc., Toronto, ON (Canada)

    2010-02-15

    The water-cooled stator windings in turbine generators suffer from various forms of corrosion induced by the presence of dissolved oxygen. In the current study, various laboratory experiments were conducted to identify a suitable catalyst for the deoxygenation of stator cooling water (SCW) systems and to qualify the material to be used in a field trial in order to confirm its deoxygenation performance. The work focused on evaluating the Lanxess (formerly Bayer) Lewatit K 7333 catalyst with respect to its physical, chemical, and oxidation stability through accelerated ageing tests as well as its performance under extreme dissolved oxygen and hydrogen concentrations. Potential effects of any water extractable leachables from the catalyst on the materials of construction of the SCW system were also studied. The catalyst was effective in removing dissolved oxygen in the presence of dissolved hydrogen and should be able to meet or exceed the dissolved oxygen specifications ({<=} 20 {mu}g . kg{sup -1}) for SCW stations that operate under low-oxygen mode. (orig.)

  7. Constraining the Extent and Intensity of Ocean De-oxygenation During Global Carbon Cycle Perturbations

    Science.gov (United States)

    Ridgwell, A. J.

    2014-12-01

    The extent and intensity of oxygen minimum zones have a first order relationship with the efficiency of nutrient and trace metal recycling in the oceans, global burial rates of organic carbon, and the availability of aerobe habitat. Reconstructing how the extent and intensity of oxygen depletion has varied with past changes in climate and global carbon cycle perturbation would enable something of the sensitivity of de-oxyenation (and its attendant impacts) to CO2 release to be quantified. However, even the extent of past de-oxygenation is notoriously difficult to constrain from the scattered and generally ocean margin and interior seaway dominated availability of observations. Spatially resolved global biogeochemical models can help, as by placing the distribution of records of any particular proxy into a global, mechanistic framework, one can make a more quantitative assessment of the observations. Moreover, multiple proxies with differing controls and sensitivities to redox state can be assessed simultaneously to help further constrain the interpretation. In this talk I will illustrate this (model-data) approach, taking examples from OAE2 and OAE1a, proxy records of seafloor anoxia and photic zone euxinia, and using the 'GENIE' Earth system model (http://mycgenie.seao2.org). I will also discuss what records and model-data approaches might be used to help better understand much subtler de-oxygenation events such as the PETM.

  8. Pyrolysis and hydrolysis of mixed polymer waste comprising polyethylene-terephthalate and polyethylene to sequentially recover [monomers

    Science.gov (United States)

    Evans, R.J.; Chum, H.L.

    1998-10-13

    A process is described for using fast pyrolysis in a carrier gas to convert a plastic waste feed stream having a mixed polymeric composition in a manner such that pyrolysis of a given polymer to its high value monomeric constituent occurs prior to pyrolysis of other plastic components therein comprising: selecting a first temperature program range to cause pyrolysis of said given polymer to its high value monomeric constituent prior to a temperature range that causes pyrolysis of other plastic components; selecting a catalyst and support for treating said feed streams with said catalyst to effect acid or base catalyzed reaction pathways to maximize yield or enhance separation of said high value monomeric constituent in said temperature program range; differentially heating said feed stream at a heat rate within the first temperature program range to provide differential pyrolysis for selective recovery of optimum quantities of the high value monomeric constituent prior to pyrolysis of other plastic components; separating the high value monomeric constituents; selecting a second higher temperature range to cause pyrolysis of a different high value monomeric constituent of said plastic waste and differentially heating the feed stream at the higher temperature program range to cause pyrolysis of the different high value monomeric constituent; and separating the different high value monomeric constituent. 83 figs.

  9. Enhancing biochar yield by co-pyrolysis of bio-oil with biomass: impacts of potassium hydroxide addition and air pretreatment prior to co-pyrolysis.

    Science.gov (United States)

    Veksha, Andrei; Zaman, Waheed; Layzell, David B; Hill, Josephine M

    2014-11-01

    The influence of KOH addition and air pretreatment on co-pyrolysis (600 °C) of a mixture of bio-oil and biomass (aspen wood) was investigated with the goal of increasing biochar yield. The bio-oil was produced as a byproduct of the pyrolysis of biomass and recycled in subsequent runs. Co-pyrolysis of the biomass with the recycled bio-oil resulted in a 16% mass increase in produced biochar. The yields were further increased by either air pretreatment or KOH addition prior to co-pyrolysis. Air pretreatment at 220 °C for 3 h resulted in the highest mass increase (32%) compared to the base case of pyrolysis of biomass only. No synergistic benefit was observed by combining KOH addition with air pretreatment. In fact, KOH catalyzed reactions that increased the bed temperature resulting in carbon loss via formation of CO and CO2. PMID:25189513

  10. Pyrolysis and dehalogenation of plastics from waste electrical and electronic equipment (WEEE): a review.

    Science.gov (United States)

    Yang, Xiaoning; Sun, Lushi; Xiang, Jun; Hu, Song; Su, Sheng

    2013-02-01

    Plastics from waste electrical and electronic equipment (WEEE) have been an important environmental problem because these plastics commonly contain toxic halogenated flame retardants which may cause serious environmental pollution, especially the formation of carcinogenic substances polybrominated dibenzo dioxins/furans (PBDD/Fs), during treat process of these plastics. Pyrolysis has been proposed as a viable processing route for recycling the organic compounds in WEEE plastics into fuels and chemical feedstock. However, dehalogenation procedures are also necessary during treat process, because the oils collected in single pyrolysis process may contain numerous halogenated organic compounds, which would detrimentally impact the reuse of these pyrolysis oils. Currently, dehalogenation has become a significant topic in recycling of WEEE plastics by pyrolysis. In order to fulfill the better resource utilization of the WEEE plastics, the compositions, characteristics and dehalogenation methods during the pyrolysis recycling process of WEEE plastics were reviewed in this paper. Dehalogenation and the decomposition or pyrolysis of WEEE plastics can be carried out simultaneously or successively. It could be 'dehalogenating prior to pyrolysing plastics', 'performing dehalogenation and pyrolysis at the same time' or 'pyrolysing plastics first then upgrading pyrolysis oils'. The first strategy essentially is the two-stage pyrolysis with the release of halogen hydrides at low pyrolysis temperature region which is separate from the decomposition of polymer matrixes, thus obtaining halogenated free oil products. The second strategy is the most common method. Zeolite or other type of catalyst can be used in the pyrolysis process for removing organohalogens. The third strategy separate pyrolysis and dehalogenation of WEEE plastics, which can, to some degree, avoid the problem of oil value decline due to the use of catalyst, but obviously, this strategy may increase the cost of whole recycling process. PMID:22951495

  11. Slow Pyrolysis of Cassava Wastes for Biochar Production and Characterization

    Directory of Open Access Journals (Sweden)

    Nurhidayah Mohamed Noor

    2012-01-01

    Full Text Available Production of biochar from slow pyrolysis of biomass is a promising carbon negative procedure since it removes the net carbon dioxide in the atmosphere and produce recalcitrant carbon suitable for sequestration in soil. Biochar production can vary significantly with the pyrolysis parameter. This study investigated the impact of temperature and heating rate on the yield and properties of biochar derived from cassava plantations residues which are cassava stem (CS and cassava rhizome (CR. The pyrolysis temperatures ranged from 400°C to 600°C while the heating rate parameter was varied from 5°C/min to 25°C/min. The experiment was conducted using the lab scale slow pyrolysis system. The increment of temperature and heating rate of slow pyrolysis for both cassava wastes had raised the fixed carbon content of the biochar but decreased the biochar yield. More biochar was produced at lower temperature and lower heating rate. Temperature gave more influence on the biochar yield as compared to the heating rate parameter. The highest biochar yield of more than 35 mf wt. % can be obtained from both CS and CR at 400°C and heating rate of 5°C/min. From the proximate analysis, the results showed that cassava wastes contain high percentage of volatile matter which is more than 80 mf wt. %. Meanwhile, the biochar produced from cassava wastes contain high percentage of fixed carbon which is about 5?8 times higher than their raw samples. This suggested that, it is a good step to convert CS and CR into high carbon biochar via slow pyrolysis process that can substantially yield more biochar, up to 37 mf wt. % in this study. Since the fixed carbon content for both CS and CR biochar produced in any studied parameter were found to be more than 75 mf wt. %, it is suggested that biochar from cassava wastes is suitable for carbon sequestration.

  12. Flash pyrolysis fuel oil: BIO-POK

    Energy Technology Data Exchange (ETDEWEB)

    Gust, S. [Neste Oy, Porvoo (Finland)

    1995-12-31

    Flash pyrolysis oil from Ensyn Tech., Canada and Union Fenosa, Spain was combusted with simple pressure atomisation equipment commonly used with light fuel oils in intermediate size (0.1-1 MW) boilers. With a number of modifications to the combustion system, carbon monoxide (CO) and nitrous oxide (NO{sub x}) could be reduced to acceptable levels: CO < 30 ppm and NO{sub x} < 140 ppm. Particulate emissions which were initially very high (Bacharach 4-5) were reduced (Bach. 2-3) by system changes but are still higher than from light fuel oil (Bach. <1). The modifications to the combustion system were: acid resistant progressive cavity pump, higher oil preheat temperature and higher oil pressure than for light fuel oils, refractory section between burner and boiler warmed up to at least 800 deg C. In addition, it was necessary to store pyrolysis oil samples under inert conditions to prevent oxidation and to rinse nozzles with alcohol after shutdown to prevent coking. The complexity and cost of these system modifications are considered to be too great for current grades of flash pyrolysis oil to be sold as a light fuel oil replacement. Improvements to fuel quality will be necessary. The main improvements are lowering of viscosity and improving of stability

  13. Thermal Pyrolysis of Polyethylene: Kinetic Study

    Directory of Open Access Journals (Sweden)

    Elham Khaghanikavkani

    2011-09-01

    Full Text Available

    Thermogravimetric analysis (TGA was used to measure the kinetic parameters of high density polyethylene in different operating conditions i.e. heating rate and nitrogen flow rate in a non isothermal condition. The Coats-Redfern method was used to calculate the kinetic parameters. An effort was made to investigate the effect of metal particles on plastic during pyrolysis. The results suggested that aluminum powder accelerates the pyrolysis reaction by enhancing the heat transfer. In addition, the kinetic reaction of pyrolysis was studied using a semi-batch reactor in a nitrogen atmosphere under isothermal and non-isothermal conditions. A first-order decomposition reaction was assumed and the rate constant was determined using an integral method. The rate constant was measured at different temperatures and was used to calculate the apparent activation energy and the pre-exponential factor of the reaction in an isothermal condition. Kinetic parameters were measured for individual compounds with carbon numbers ranging from C9 to C50 using the semi batch reactor under isothermal condition.

    Key words: Kinetic; High density polyethylene; Isothermal; Non isothermal; TGA; Semi batch reactor

  14. Oil production by entrained pyrolysis of biomass and processing of oil and char

    Science.gov (United States)

    Knight, James A. (Atlanta, GA); Gorton, Charles W. (Atlanta, GA)

    1990-01-02

    Entrained pyrolysis of lignocellulosic material proceeds from a controlled pyrolysis-initiating temperature to completion of an oxygen free environment at atmospheric pressure and controlled residence time to provide a high yield recovery of pyrolysis oil together with char and non-condensable, combustible gases. The residence time is a function of gas flow rate and the initiating temperature is likewise a function of the gas flow rate, varying therewith. A controlled initiating temperature range of about 400.degree. C. to 550.degree. C. with corresponding gas flow rates to maximize oil yield is disclosed.

  15. Impact of thermal pretreatment on the fast pyrolysis conversion of Southern Pine

    Energy Technology Data Exchange (ETDEWEB)

    Tyler L. Westover; Manunya Phanphanich; Micael L. Clark; Sharna R. Rowe; Steven E. Egan; Christopher T Wright; Richard D. Boardman; Alan H. Zacher

    2013-01-01

    Background: Thermal pretreatment of biomass ranges from simple (nondestructive) drying to more severe treatments that cause devolatization, depolymerization and carbonization. These pretreatments have demonstrated promise for transforming raw biomass into feedstock material that has improved milling, handling, storage and conversion properties. In this work, southern pine material was pretreated at 120, 180, 230 and 270 degrees C, and then subjected to pyrolysis tests in a continuous-feed bubbling-fluid bed pyrolysis system. Results: High pretreatment temperatures were associated with lower specific grinding energies, higher grinding rates and lower hydrogen and oxygen contents. Higher pretreatment temperatures were also correlated with increased char production, decreased total acid number and slight decrease in the oxygen content of the pyrolysis liquid fraction. Conclusion: Thermal pretreatment has both beneficial and detrimental impacts on fast pyrolysis conversion of pine material to bio-oil, and the effect of thermal pretreatment on upgrading of pyrolysis bio-oil requires further attention.

  16. Characterization of bio-oil obtained from fruit pulp pyrolysis

    International Nuclear Information System (INIS)

    Apricot pulps was pyrolyzed in a fixed-bed reactor under different pyrolysis conditions to determine the role of final temperature, sweeping gas flow rate and steam velocity on the product yields and liquid product composition with a heating rate of 5 deg. C/min. Final temperature range studied was between 300 and 700 deg. C and the highest liquid product yield was obtained at 550 deg. C. Liquid product yield increased significantly under nitrogen and steam atmospheres. For the optimum conditions, pyrolysis of peach pulp was furthermore studied. Liquid products obtained under the most suitable conditions were characterized by FTIR and 1H-NMR. In addition, gas chromatography/mass spectrophotometer was achieved on all pyrolysis oils. Characterization showed that bio-oil could be a potential source for synthetic fuels and chemical feedstock

  17. Studies on Catalytic Pyrolysis of Mustard Press Cake with NaCl

    OpenAIRE

    Aparna Sarkar1; Ranjana Chowdhury

    2014-01-01

    Under this present investigation, non-catalytic and catalytic pyrolysis of mustard press cake (MPC) was conducted in a 50 mm diameter and 640 mm long semi-batch pyrolyser in the temperature range of 673K to 1173K in a nitrogen atmosphere. Effects of temperature on yields of products, namely, char, pyro-oil and gas obtained from primary pyrolysis of MPC have been investigated. The kinetic rate constants of volatiles and char formations were determined in the temperature range u...

  18. A comprehensive study of methyl decanoate pyrolysis

    International Nuclear Information System (INIS)

    The thermal decomposition of methyl decanoate (MD) was studied in a bench-scale pyrolysis set-up equipped with a dedicated on-line analysis section including a GC × GC-FID/(TOF-MS). This analysis section enables quantitative and qualitative on-line analyses of the entire reactor effluent with high level of detail including measurement of formaldehyde and water. The reactor temperature was varied from 873 K to 1123 K at a fixed pressure of 1.7 bar and a fixed residence time of 0.5 s, for both high (10molN2/molMD) and low (0.6molN2/molMD) nitrogen dilution. Thus covering a wide conversion range in both dilution regimes. In these experiments, significant amounts of large linear olefins and unsaturated esters were observed at lower temperatures, the amounts of which decreased at higher temperatures in favor of permanent gasses (CO, CO2, CH4) and light olefins. At the highest temperatures more than 5 wt% of mono-aromatic and poly-aromatic components were observed. The acquired dataset was used to validate 3 recently published microkinetic models which were developed to model oxidation and/or pyrolysis of methyl decanoate. The results showed that these models accurately predict the product distribution, although important discrepancies were observed for some major products such as certain unsaturated esters, CO2 and H2O. Reaction path analyses and CBS-QB3 quantum-chemical calculations are presented and discussed in order to explain the observed differences. -- Highlights: ? New extensive experimental dataset for the pyrolysis of methyl decanoate in a tubular reactor. ? A dedicated separation section including on-line GC × GC allows to obtain quantitative data for over 150 components. ? High level ab-initio calculations for important reactions of the methyl decanoate decomposition. ? Identification of missing reactions/reaction families/inaccurate kinetics in the presently available kinetic models.

  19. Radicals from the gas-phase pyrolysis of catechol. 2. Comparison of the pyrolysis of catechol and hydroquinone.

    Science.gov (United States)

    Khachatryan, Lavrent; Asatryan, Rubik; McFerrin, Cheri; Adounkpe, Julien; Dellinger, Barry

    2010-09-23

    Formation of radicals from the pyrolysis of catechol (CT) and hydroquinone (HQ) over a temperature range of 350-900 °C was studied using low-temperature matrix isolation electron paramagnetic resonance (LTMI EPR) spectroscopy. Comparative analysis of the pyrolysis mechanisms of these isomeric compounds was performed, and the role of semiquinone-type carrier radicals was studied. Pathways of unimolecular decomposition of intermediate radicals and molecular products were identified from the examination of the potential energy surface of catechol calculated at B3LYP hybrid density functional theory and composite CBS-QB3 levels. The results were compared with the experimental observations and mechanistic pathways previously developed for the pyrolysis of hydroquinone. PMID:20731470

  20. Preconversion catalytic deoxygenation of phenolic functional groups. Quarterly technical progress report, April 1, 1991--June 30, 1991

    Energy Technology Data Exchange (ETDEWEB)

    Kubiak, C.P.

    1991-12-31

    The deoxygenation of phenols is a conceptually simple, but unusually difficult chemical transformation to achieve. Aryl carbon-oxygen bond cleavage is a chemical transformation of importance in coal liquefaction and the upgrading of coal liquids as well as in the synthesis of natural products. This proposed research offers the possibility of effecting the selective catalytic deoxygenation of phenolic functional groups using CO. A program of research for the catalytic deoxygenation of phenols, via a low energy mechanistic pathway that is based on the use of the CO/CO{sub 2} couple to remove phenolic oxygen atoms, is underway. We are focusing on systems which have significant promise as catalysts: Ir(triphos)OPh, [Pt(triphos)OPh]{sup +} and Rh(triphos)OPh. Our studies of phenol deoxygenation focus on monitoring the reactions for the elementary processes upon which catalytic activity will depend: CO insertion into M-OPh bonds, CO{sub 2} elimination from aryloxy carbonyls {l_brace}M-C(O)-O-Ph{r_brace}, followed by formation of a coordinated benzyne intermediate.

  1. Effect of support-active phase interactions on the catalyst activity and selectivity in deoxygenation of triglycerides.

    Czech Academy of Sciences Publication Activity Database

    Kubi?ka, D.; Horá?ek, J.; Setni?ka, M.; Bulánek, R.; Zukal, Arnošt; Kubi?ková, I.

    2014-01-01

    Ro?. 145, FEB 2014 (2014), s. 101-107. ISSN 0926-3373 R&D Projects: GA ?R GBP106/12/G015 Institutional support: RVO:61388955 Keywords : Deoxygenation * Vegetable oils * Effect of support Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 7.435, year: 2014

  2. The role of Ni species in the deoxygenation of rapeseed oil over NiMo-alumina catalysts.

    Czech Academy of Sciences Publication Activity Database

    Priecel, P.; Kubi?ka, D.; ?apek, L.; Bastl, Zden?k; Ryšánek, P.

    2011-01-01

    Ro?. 397, 1-2 (2011), s. 127-137. ISSN 0926-860X Institutional research plan: CEZ:AV0Z40400503 Keywords : deoxygenation * NiMo-alumina * UV-vis Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.903, year: 2011

  3. A Comparative study of microwave-induced pyrolysis of lignocellulosic and algal biomass.

    Science.gov (United States)

    Wang, Nan; Tahmasebi, Arash; Yu, Jianglong; Xu, Jing; Huang, Feng; Mamaeva, Alisa

    2015-08-01

    Microwave (MW) pyrolysis of algal and lignocellulosic biomass samples were studied using a modified domestic oven. The pyrolysis temperature was recorded continuously by inserting a thermocouple into the samples. Temperatures as high as 1170 and 1015°C were achieved for peanut shell and Chlorella vulgaris. The activation energy for MW pyrolysis was calculated by Coats-Redfern method and the values were 221.96 and 214.27kJ/mol for peanut shell and C. vulgaris, respectively. Bio-oil yields reached to 27.7wt.% and 11.0wt.% during pyrolysis of C. vulgaris and peanut shell, respectively. The bio-oil samples from pyrolysis were analyzed by a gas chromatography-mass spectrometry (GC-MS). Bio-oil from lignocellulosic biomass pyrolysis contained more phenolic compounds while that from microalgae pyrolysis contained more nitrogen-containing species. Fourier transform infrared spectroscopy (FTIR) analysis results showed that concentration of OH, CH, CO, OCH3, and CO functional groups in char samples decreased significantly after pyrolysis. PMID:25935388

  4. Environmental fatigue behaviors of wrought and cast stainless steels in 310degC deoxygenated water

    International Nuclear Information System (INIS)

    Environmental fatigue behaviors of wrought type 316LN stainless steel and cast CF8M stainless steel were investigated. Low cycle fatigue tests were performed in a 310degC deoxygenated water environment at a strain rate of 0.04%/s with various strain amplitudes. It was shown that the low cycle fatigue life of CF8M was slightly longer than that of 316LN. To understand the causes of the difference, fracture surface was observed and material factors like microstructure, mechanical properties, and chemical compositions of both materials were analyzed. In a duplex microstructure of CF8M, the fatigue crack growth was affected by barrier role of ferrite phase and acceleration role of microvoids in ferrite phase. Test results indicate that the former is greater than the latter, resulting in slower fatigue crack growth rate, or longer LCF lives in CF8M than in 316LN. (author)

  5. Characterization of fiber/matrix bonding strenth during the pyrolysis of CFRP to C/C composites

    OpenAIRE

    Sha, J; Wu, G.; Dai, J.; Zhang, Y.; Hausherr, J.-M.; Konschak, A.; Krenkel, W.

    2011-01-01

    The fiber/matrix bonding strength during the pyrolysis of CFRP to C/C composite was measured by single fiber push-out test with a microindentation method. The composites in their polymeric state show a high fiber/matrix bonding strength. After pyrolysis at elevated temperatures the fiber/matrix bonding strength decreases. Such result would be beneficial to the understanding of microstructure evolution mechanism during the pyrolysis of CFRP to C/C composites.

  6. Pyrolysis of furan in a microreactor

    Science.gov (United States)

    Urness, Kimberly N.; Guan, Qi; Golan, Amir; Daily, John W.; Nimlos, Mark R.; Stanton, John F.; Ahmed, Musahid; Ellison, G. Barney

    2013-09-01

    A silicon carbide microtubular reactor has been used to measure branching ratios in the thermal decomposition of furan, C4H4O. The pyrolysis experiments are carried out by passing a dilute mixture of furan (approximately 0.01%) entrained in a stream of helium through the heated reactor. The SiC reactor (0.66 mm i.d., 2 mm o.d., 2.5 cm long) operates with continuous flow. Experiments were performed with a reactor inlet pressure of 100-300 Torr and a wall temperature between 1200 and 1600 K; characteristic residence times in the reactor are 60-150 ?s. The unimolecular decomposition pathway of furan is confirmed to be: furan (+ M) rightleftharpoons ?-carbene or ?-carbene. The ?-carbene fragments to CH2=C=O + HC?CH while the ?-carbene isomerizes to CH2=C=CHCHO. The formyl allene can isomerize to CO + CH3C?CH or it can fragment to H + CO + HCCCH2. Tunable synchrotron radiation photoionization mass spectrometry is used to monitor the products and to measure the branching ratio of the two carbenes as well as the ratio of [HCCCH2]/[CH3C?CH]. The results of these pyrolysis experiments demonstrate a preference for 80%-90% of furan decomposition to occur via the ?-carbene. For reactor temperatures of 1200-1400 K, no propargyl radicals are formed. As the temperature rises to 1500-1600 K, at most 10% of the decomposition of CH2=C=CHCHO produces H + CO + HCCCH2 radicals. Thermodynamic conditions in the reactor have been modeled by computational fluid dynamics and the experimental results are compared to the predictions of three furan pyrolysis mechanisms. Uncertainty in the pressure-dependency of the initiation reaction rates is a possible a source of discrepancy between experimental results and theoretical predictions.

  7. Catalytic Fast Pyrolysis: A Review

    OpenAIRE

    Theodore Dickerson; Juan Soria

    2013-01-01

    Catalytic pyrolysis is a promising thermochemical conversion route for lignocellulosic biomass that produces chemicals and fuels compatible with current, petrochemical infrastructure. Catalytic modifications to pyrolysis bio-oils are geared towards the elimination and substitution of oxygen and oxygen-containing functionalities in addition to increasing the hydrogen to carbon ratio of the final products. Recent progress has focused on both hydrodeoxygenation and hydrogenation of bio-oil using...

  8. Pyrolysis and volatilization of cocaine

    International Nuclear Information System (INIS)

    The increasing popularity of inhaling cocaine vapor prompted the present study, to determine cocaine's fate during this process. The free base of [3H]cocaine (1 microCi/50 mg) was added to a glass pipe, which was then heated in a furnace to simulate freebasing. Negative pressure was used to draw the vapor through a series of glass wool, ethanol, acidic, and basic traps. Air flow rate and temperature were found to have profound effects on the volatilization and pyrolysis of cocaine. At a temperature of 260 degrees C and a flow rate of 400 mL/min, 37% of the radioactivity remained in the pipe, 39% was found in the glass wool trap, and less than 1% in the remainder of the volatilization apparatus after a 10-min volatilization. Reducing the air flow rate to 100 mL/min reduced the amount of radioactivity collected in the glass wool trap to less than 10% of the starting material and increased the amount that remained in the pipe to 58%. GC/MS analysis of the contents of the glass wool trap after volatilization at 260 degrees C and a flow rate of 400 mL/min revealed that 60% of the cocaine remained intact, while approximately 6 and 2% of the starting material was recovered as benzoic acid and methylecgonidine, respectively. As the temperature was increased to 650 degrees C, benzoic acid and methylecgonidine accounted for 83 and 89% of the starting material, respectively, whereas only 2% of the cocaine remained intact. Quantitation of cocaine in the vapor during the course of cocaine in the vapor during the course of volatilization revealed high concentrations during the first two min and low concentrations for the remaining time

  9. Pyrolysis and co-pyrolysis of Laminaria japonica and polypropylene over mesoporous Al-SBA-15 catalyst

    Science.gov (United States)

    Lee, Hyung Won; Choi, Suek Joo; Park, Sung Hoon; Jeon, Jong-Ki; Jung, Sang-Chul; Kim, Sang Chai; Park, Young-Kwon

    2014-08-01

    The catalytic co-pyrolysis of a seaweed biomass, Laminaria japonica, and a typical polymer material, polypropylene, was studied for the first time. A mesoporous material Al-SBA-15 was used as a catalyst. Pyrolysis experiments were conducted using a fixed-bed reactor and pyrolysis gas chromatography/mass spectrometry (Py-GC/MS). BET surface area, N2 adsorption-desorption isotherms, and NH3 temperature programmed desorption were measured to examine the catalyst characteristics. When only L. japonica was pyrolyzed, catalytic reforming slightly increased the gas yield and decreased the oil yield. The H2O content in bio-oil was increased by catalytic reforming from 42.03 to 50.32 wt% due to the dehydration reaction occurring on the acid sites inside the large pores of Al-SBA-15. Acids, oxygenates, mono-aromatics, poly aromatic hydrocarbons, and phenolics were the main components of the bio-oil obtained from the pyrolysis of L. japonica. Upon catalytic reforming over Al-SBA-15, the main oxygenate species 1,4-anhydro- d-galactitol and 1,5-anhydro- d-manitol were completely removed. When L. japonica was co-pyrolyzed with polypropylene, the H2O content in bio-oil was decreased dramatically (8.93 wt% in the case of catalytic co-pyrolysis), contributing to the improvement of the oil quality. A huge increase in the content of gasoline-range and diesel-range hydrocarbons in bio-oil was the most remarkable change that resulted from the co-pyrolysis with polypropylene, suggesting its potential as a transport fuel. The content of mono-aromatics with high economic value was also increased significantly by catalytic co-pyrolysis.

  10. Pyrolysis of coal with nitric acid treatment

    Energy Technology Data Exchange (ETDEWEB)

    Soneda, Y.; Makino, M.; Kaiho, M. [National Institute of Resources and Environment, Tsukuba (Japan)

    1994-12-31

    Four coal samples, Wandoan, Datong, Taiheiyo and Mequinenza, were treated with nitric acid and the inorganic sulfur compounds in coal were removed. The amount of hydrogen sulfide liberated from the coal by the nitric acid treatment during pyrolysis in hydrogen increased in comparison with raw coals and its liberation curves plotted against temperature also changed. It is suggested from {sup 13}C-NMR and FT-IR measurement of raw and treated coal samples that the oxidation of coals by nitric acid treatment was not remarkable, while the amounts of aliphatic carbons in treated coals were slightly decreased. 3 figs.

  11. Gas phase temperature measurements in the liquid and particle regime of a flame spray pyrolysis process using O2-based pure rotational coherent anti-Stokes Raman scattering.

    Science.gov (United States)

    Engel, Sascha R; Koegler, Andreas F; Gao, Yi; Kilian, Daniel; Voigt, Michael; Seeger, Thomas; Peukert, Wolfgang; Leipertz, Alfred

    2012-09-01

    For the production of oxide nanoparticles at a commercial scale, flame spray processes are frequently used where mostly oxygen is fed to the flame if high combustion temperatures and thus small primary particle sizes are desired. To improve the understanding of these complex processes in situ, noninvasive optical measurement techniques were applied to characterize the extremely turbulent and unsteady combustion field at those positions where the particles are formed from precursor containing organic solvent droplets. This particle-forming regime was identified by laser-induced breakdown detection. The gas phase temperatures in the surrounding of droplets and particles were measured with O(2)-based pure rotational coherent anti-Stokes Raman scattering (CARS). Pure rotational CARS measurements benefit from a polarization filtering technique that is essential in particle and droplet environments for acquiring CARS spectra suitable for temperature fitting. Due to different signal disturbing processes only the minority of the collected signals could be used for temperature evaluation. The selection of these suitable signals is one of the major problems to be solved for a reliable evaluation process. Applying these filtering and signal selection steps temperature measurements have successfully been conducted. Time-resolved, single-pulse measurements exhibit temperatures between near-room and combustion temperatures due to the strongly fluctuating and flickering behavior of the particle-generating flame. The mean flame temperatures determined from the single-pulse data are decreasing with increasing particle concentrations. They indicate the dissipation of large amounts of energy from the surrounding gas phase in the presence of particles. PMID:22945152

  12. ANALYSIS OF VOLATILE PRODUCTS FROM THE SLOW PYROLYSIS OF COAL

    Science.gov (United States)

    The report gives results of a study of the evolution of volatile matter from coals of various rank during fixed-and fluid-bed pyrolysis. The pyrolyses were performed at temperatures ranging from 400 to 1000 C and with heating rates ranging from 1.5 to 6.0 C/s. Effects of equilibr...

  13. Pyrolysis of activated sludge: energy analysis and its technical feasibility.

    Science.gov (United States)

    Agarwal, Manu; Tardio, James; Venkata Mohan, S

    2015-02-01

    A comprehensive study on the potential of pyrolysis of activated sludge to generate substances that can be used to produce energy was evaluated for its technical and environmental viability. The products of the process viz., pyrolysis gas, pyrolysis oil and char can readily be used by the major energy consumers viz., electricity and transportation. Based on the results obtained it is estimated that a 1 ton capacity process for pyrolysis of activated sludge can serve the electrical needs of a maximum of 239, 95 and 47 Indian houses per day, considering lower middle class, middle class and upper middle class, respectively. In addition the process would also produce the daily methane (CNG) requirement of 128 public transport buses. The process was determined to be technically feasible at low and medium temperatures for both, pyrolysis gas and electrical energy. The gas generated could be utilized as fuel directly while the oil generated would require pretreatment before its potential application. The process is potentially sustainable when commercialized and can self-sustain in continuous mode of operation in biorefinery context. PMID:25451771

  14. Co-pyrolysis of lignite and sugar beet pulp

    International Nuclear Information System (INIS)

    Today, worldwide studies have been undertaken on the biomass usage and co-conversion of biomass and coal to seek out alternative fuels for supplying energy in an environmental friendly way. The objective of this work is to study co-pyrolysis of lignite and sugar beet pulp in 50/50 (wt./wt.) ratio of blend pellets, to elucidate their thermal behaviour under pyrolysis conditions and to assess major decomposition products in terms of their yields. A special chamber, which has enabled very fast heating rates, was used in the pyrolysis experiments carried at 600 deg. C. The results were interpreted in the light of liquid, solid and gaseous yields, resulting from thermal decomposition, and kinetics of thermogravimetric analysis. Proximate volatile matter and ash contents of the blends were different compared to those found by using individual values. Sugar beet pulp decomposed faster within a relatively narrow temperature range than lignite and underwent a significant shrinkage during pyrolysis. It was found that the chars left behind after the flash pyrolysis of these pellets at 600 deg. C have substantial amounts of volatile matter that would evolve upon further heating.

  15. Pyrolysis of Softwood Carbohydrates in a Fluidized Bed Reactor

    OpenAIRE

    Dmitry Yu. Murzin; Tapio Salmi; Mikko Hupa; Bjarne Holmbom; Kari Eränen; Narendra Kumar; Atte Aho

    2008-01-01

    In the present work pyrolysis of pure pine wood and softwood carbohydrates, namely cellulose and galactoglucomannan (the major hemicellulose in coniferous wood), was conducted in a batch mode operated fluidized bed reactor. Temperature ramping (5°C/min) was applied to the heating until a reactor temperature of 460 °C was reached. Thereafter the temperature was kept until the release of non-condensable gases stopped. The different raw materials gave significantly different bio-oils. Levo...

  16. STEPWISE ISOTHERMAL FAST PYROLYSIS (SIFP. PART II. SIFP OF PEANUT SHELLS - ANTIFUNGAL PROPERTIES OF PHENOLIC FRACTIONS

    Directory of Open Access Journals (Sweden)

    Jorge Daniel Pérez

    2011-11-01

    Full Text Available Pyrolysis of peanut shells was carried out using stepwise isothermal fast pyrolysis (SIFP. SIFP consists of successive isothermal fast pyrolysis reactions, where solid products obtained in the previous isothermal fast pyrolysis become the substrate of the subsequent reaction at a higher temperature. This article reports results obtained from SIFP of peanut shells between 200 and 300°C using 100°C intervals under vacuum (0.2 mm. The maximum yield of liquid products was obtained at 300°C, giving around 30% of bio-oil, which contained mainly phenols and furan derivatives. On the other hand, since previous papers have reported fungicidal activity of phenols derivatives from lingo-cellulosic biomass pyrolysis, we carried out antifungal activity tests of bio oil obtained from peanut shells SIFT at 300 °C. Results seem promising, at least on Sclerotium rolfsii.

  17. Thermogravimetric study and kinetic analysis of dried industrial sludge pyrolysis.

    Science.gov (United States)

    Liu, Guangrui; Song, Huijuan; Wu, Jinhu

    2015-07-01

    Thermogravimetric experiments of two different industrial sludge samples were carried out with non-isothermal temperature programs. The results indicated that the pyrolysis process contains three obvious stages and the main decomposition reaction occurred in the range of 200-600°C. The distributed activation energy model (DAEM) was also proposed describing equally well the pyrolysis behavior of the samples. The calculated activation energy was ranged from 170 to 593kJ/mol and 125 to 756kJ/mol for SLYG (sludge sample from chemical fiber factory) and SQD (sludge sample from woody industry), respectively. The reliability of this model not only provided good fit for all experiments, but also allowed accurate extrapolations to relative higher heating rates. Besides, the FTIR measurement was also used to further understand the relationship between pyrolysis behavior and chemical structures for industrial sludge. PMID:25892437

  18. Experimental investigation of flash pyrolysis oil droplet combustion

    DEFF Research Database (Denmark)

    Ibrahim, Norazana; Jensen, Peter A.

    2013-01-01

    The aim of this work is to investigate and compare the combustion behaviour of a single droplet of pyrolysis oil derived from wheat straw and heavy fossil oil in a single droplet combustion chamber. The initial oil droplet diameters were in between 500 ?m to 2500 ?m. The experiments were performed at a temperature ranging between 1000 and 1400°C with an initial gas velocity of 1.6 m/s and oxygen concentration of 3%. The evolution of combustion of bio-oil droplets was recorded by a digital video camera. It was observed that the combustion behaviour of pyrolysis oil droplet differ from the heavy oil in terms both of ignition, devolatilisation and char oxidation. The pyrolysis oil is more difficult to ignite and has a shorter devolatilisation time and a longer char oxidation time. Copyright © 2013, AIDIC Servizi S.r.l.

  19. Specialists' workshop on fast pyrolysis of biomass

    Energy Technology Data Exchange (ETDEWEB)

    1980-01-01

    This workshop brought together most of those who are currently working in or have published significant findings in the area of fast pyrolysis of biomass or biomass-derived materials, with the goal of attaining a better understanding of the dominant mechanisms which produce olefins, oxygenated liquids, char, and tars. In addition, background papers were given in hydrocarbon pyrolysis, slow pyrolysis of biomass, and techniques for powdered-feedstock preparation in order that the other papers did not need to introduce in depth these concepts in their presentations for continuity. In general, the authors were requested to present summaries of experimental data with as much interpretation of that data as possible with regard to mechanisms and process variables such as heat flux, temperatures, partial pressure, feedstock, particle size, heating rates, residence time, etc. Separate abstracts have been prepared of each presentation for inclusion in the Energy Data Base. (DMC)

  20. Vacuum Pyrolysis and Related ISRU Techniques

    Science.gov (United States)

    Cardiff, Eric H.; Pomeroy, Brian R.; Banks, Ian S.; Benz, Alexis

    2007-01-01

    A number of ISRU-related techniques have been developed at NASA Goddard Space Flight Center. The focus of the team has been on development of the vacuum pyrolysis technique for the production of oxygen from the lunar regolith. However, a number of related techniques have also been developed, including solar concentration, solar heating of regolith, resistive heating of regolith, sintering, regolith boiling, process modeling, parts manufacturing, and instrumentation development. An initial prototype system was developed to vaporize regolith simulants using a approx. l square meter Fresnel lens. This system was successfully used to vaporize quantities of approx. lg, and both mass spectroscopy of the gasses produced and Scanning Electron Microscopy (SEM) of the slag were done to show that oxygen was produced. Subsequent tests have demonstrated the use of a larger system With a 3.8m diameter reflective mirror to vaporize the regolith. These results and modeling of the vacuum pyrolysis reaction have indicated that the vaporization of the oxides in the regolith will occur at lower temperature for stronger vacuums. The chemical modeling was validated by testing of a resistive heating system that vaporized quantities of approx. 10g of MLS-1A. This system was also used to demonstrate the sintering of regolith simulants at reduced temperatures in high vacuum. This reduction in the required temperature prompted the development of a small-scale resistive heating system for application as a scientific instrument as well as a proof-of principle experiment for oxygen production.

  1. Organic emissions from coal pyrolysis: mutagenic effects.

    Science.gov (United States)

    Braun, A G; Wornat, M J; Mitra, A; Sarofim, A F

    1987-08-01

    Four different types of coal have been pyrolyzed in a laminar flow, drop tube furnace in order to establish a relationship between polycyclic aromatic compound (PAC) evolution and mutagenicity. Temperatures of 900K to 1700K and particle residence times up to 0.3 sec were chosen to best simulate conditions of rapid rate pyrolysis in pulverized (44-53 microns) coal combustion. The specific mutagenic activity (i.e., the activity per unit sample weight) of extracts from particulates and volatiles captured on XAD-2 resin varied with coal type according to the order: subbituminous greater than high volatile bituminous greater than lignite greater than anthracite. Total mutagenic activity (the activity per gram of coal pyrolyzed), however, varied with coal type according to the order: high volatile bituminous much greater than subbituminous = lignite much greater than anthracite, due primarily to high organic yield during high volatile bituminous coal pyrolysis. Specific mutagenic activity peaked in a temperature range of 1300K to 1500K and generally appeared at higher temperatures and longer residence times than peak PAC production. PMID:3311724

  2. Fast pyrolysis of sugarcane and cassava residues in a free-fall reactor

    International Nuclear Information System (INIS)

    Fast pyrolysis of agricultural residues from sugarcane and cassava plantations was carried out in a laboratory-scale free-fall reactor unit. The objectives of this work were to investigate the effects of biomass types and pyroysis conditions, such as reactor temperature, condensation temperature, nitrogen flow rate and run duration, on pyrolysis product distribution, as well as to study the basic properties of the products. The results showed that all of the parameters affected the product distribution. The optimum reactor temperatures for maximising bio-oil yield were in the range of 350–450 °C. About 70 wt% of bio-oil yield could be obtained by pyrolysis of cassava stalk at a reactor temperature of 450 °C and a primary condensation temperature of 10 °C. It was also found that the minimum flow rate of nitrogen for obtaining high bio-oil yield was 1.5 l/min. The product characterisation showed that the bio-oil and char produced from the agricultural residues with the free-fall reactor unit were to a certain extent similar to those produced from different types of biomass with different types of pyrolysis reactor configurations. -- Highlights: ? Fast pyrolysis of sugarcane and cassava agricultural residues was carried out in a laboratory-scale free-fall reactor unit. ? The effects of process parameters on product yields were investigated. ? The process parameters included reactor temperature, condensation temperature, nitrogen flow rate and run duration. Basic properties of pyrolysis products were examined.

  3. Characterization of the different fractions obtained from the pyrolysis of rope industry waste

    OpenAIRE

    Andrade, Marta; Parra Soto, José Bernardo; Haro Remón, Marta; Mestre, Ana S.; Carvalho, A. P.; Ovín Ania, María Concepción

    2012-01-01

    A study of the possibilities of pyrolysis for recovering wastes of the rope's industry has been carried out. The pyrolysis of this lignocellulosic residue started at 250 °C, with the main region of decomposition occurring at temperatures between 300 and 350 °C. As the reaction temperature increased, the yields of pyrolyzed gas and oil increased, yielding 22 wt.% of a carbonaceous residue, 50 wt.% tars and a gas fraction at 800 °C. The chemical composition and textural characterization of the ...

  4. Microwave pyrolysis for conversion of materials to energy : A review

    International Nuclear Information System (INIS)

    Full text: The disposal of wastes in Malaysia is becoming a serious problem in many industrialized and public sectors. This is due to the high production of waste such as municipal solid waste, sludge from waste water treatment plants, agricultural waste and other used non-biodegradable products such as plastics and tyres. These wastes although are reused as compost, fuel, recycled and so on, there are still abundant left. These leftovers pose problems such as heavy metal leaching, leachates, green house gas emissions and mosquito breeding grounds. The disposal cost of these wastes sometimes can be costly at up to RM 2,200/ ton such as petroleum sludge by Kualiti Alam. Several methods have been used to convert these residues to energy via thermal treatment such as combustion, incineration and gasification. However, pyrolysis becomes one of the popular methods as the alternative to the wastes disposal recently. Not only energy (as gas) is produced, by-products such as chemical feedstock and solid absorbent can be produced. The use of microwave for pyrolysis, although relatively new for waste treatment, has several advantages compared to conventional heating. This includes easy control of the heating process, time saving, higher heating efficiency, etc. Tyre microwave pyrolysis plant in UK is known as the earliest plant using microwave technology to breakdown polymer in used tyres. Since 1990s, there are many patents for microwave pyrolysis. The processes are based on mve pyrolysis. The processes are based on microwave pyrolysis of waste include coffee hulls, wood, coal, sewage sludge, hospital waste, plastic wastes, corn cobs and rice straw. The most important factors influencing the yield of product during the pyrolysis is temperature in range from 500 to 1000 degree Celsius according to product preference. High temperature favors gas products; whereas lower temperature favors liquid products. Comparatively, microwave pyrolysis produced gas with higher hydrogen and carbon monoxide (syngas) content compared to conventional heating. Liquid product also showed considerable decrease in polycyclic aromatic hydrocarbons (PAH) production which is of known carcinogenic. Vitrification of heavy metals in solid product has also been proven. (author)

  5. Co-pyrolysis of coal with organic solids

    Energy Technology Data Exchange (ETDEWEB)

    Straka, P.; Buchtele, J. [Inst. of Rock Structure and Mechanics, Prague (Czechoslovakia)

    1995-12-01

    The co-pyrolysis of high volatile A bituminous coal with solid organic materials (proteins, cellulose, polyisoprene, polystyrene, polyethylene-glycolterephtalate-PEGT) at a high temperature conditions was investigated. Aim of the work was to evaluate, firstly, the changes of the texture and of the porous system of solid phase after high temperature treatment in presence of different types of macromolecular solids, secondly, properties and composition of the tar and gas. Considered organic solids are important waste components. During their co-pyrolysis the high volatile bituminous coal acts as a hydrogen donor in the temperature rank 220-480{degrees}C. In the rank 500- 1000{degrees}C the solid phase is formed. The co-pyrolysis was carried out at heating rate 3 K/min. It was found that an amount of organic solid (5-10%) affects important changes in the optical texture forms of solid phase, in the pore distribution and in the internal surface area. Transport large pores volume decreases in presence of PEGT, polystyrene and cellulose and increases in presence of proteins and polyisoprene. (image analysis measurements show that the tendency of coal to create coarse pores during co-pyrolysis is very strong and increases with increasing amount of organic solid in blend). An addition of considered materials changes the sorption ability (methylene blue test, iodine adsorption test), moreover, the reactivity of the solid phase.

  6. Bio-Fuel Production Assisted with High Temperature Steam Electrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Grant Hawkes; James O' Brien; Michael McKellar

    2012-06-01

    Two hybrid energy processes that enable production of synthetic liquid fuels that are compatible with the existing conventional liquid transportation fuels infrastructure are presented. Using biomass as a renewable carbon source, and supplemental hydrogen from high-temperature steam electrolysis (HTSE), these two hybrid energy processes have the potential to provide a significant alternative petroleum source that could reduce dependence on imported oil. The first process discusses a hydropyrolysis unit with hydrogen addition from HTSE. Non-food biomass is pyrolyzed and converted to pyrolysis oil. The pyrolysis oil is upgraded with hydrogen addition from HTSE. This addition of hydrogen deoxygenates the pyrolysis oil and increases the pH to a tolerable level for transportation. The final product is synthetic crude that could then be transported to a refinery and input into the already used transportation fuel infrastructure. The second process discusses a process named Bio-Syntrolysis. The Bio-Syntrolysis process combines hydrogen from HTSE with CO from an oxygen-blown biomass gasifier that yields syngas to be used as a feedstock for synthesis of liquid synthetic crude. Conversion of syngas to liquid synthetic crude, using a biomass-based carbon source, expands the application of renewable energy beyond the grid to include transportation fuels. It can also contribute to grid stability associated with non-dispatchable power generation. The use of supplemental hydrogen from HTSE enables greater than 90% utilization of the biomass carbon content which is about 2.5 times higher than carbon utilization associated with traditional cellulosic ethanol production. If the electrical power source needed for HTSE is based on nuclear or renewable energy, the process is carbon neutral. INL has demonstrated improved biomass processing prior to gasification. Recyclable biomass in the form of crop residue or energy crops would serve as the feedstock for this process. A process model of syngas production using high temperature electrolysis and biomass gasification is presented. Process heat from the biomass gasifier is used to heat steam for the hydrogen production via the high temperature steam electrolysis process. Oxygen produced form the electrolysis process is used to control the oxidation rate in the oxygen-blown biomass gasifier.

  7. Fast pyrolysis of lignin, macroalgae and sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Trinh, N.T.

    2013-04-15

    Non-conventional biomass feedstock may also be applicable for fast pyrolysis processes. Among the forms of non-conventional biomasses, macroalgae, lignin (industrial residue) and sewage sludge may be attractive materials due to their low price, non-competitiveness with food crops and the possible utilization of solid wastes. Besides, a fast pyrolysis process can be used as a process to densify the biomass and produce bioslurry, a mixture of bio-oil and pyrolytic char. The bioslurry is found to be a possible feedstock for pressurized gasification plants. Thus, the aims of this project are to investigate fast pyrolysis properties of lignin, sewage sludge and macroalgae on a lab scale PCR and characterize their bio-oil properties. Bioslurry properties with respect to use as a feedstock for pressurized gasification is also investigated. Lignin and sewage sludge PCR pyrolysis provided bio-oil yields of 47 and 54 wt% daf, and oil energy recovery of 45 and 50 %, respectively. While the macroalgae PCR pyrolysis showed promising results with an organic oil yield of 65 wt% daf and an oil energy recovery of 76 %. The HHV of the lignin, sewage sludge and macroalgae oils were 29.7, 25.7 and 25.5 MJ/kg db respectively, and that are higher than that of typical bioiv oil from conventional biomasses (23-24 MJ/kg db). Almost all metals feedstock contents were contained in the chars at temperatures of 550 - 575 deg. C for lignin, sewage sludge and macroalgae PCR pyrolysis. Due to high feedstock nitrogen and sulfur contents, also a high level of nitrogen and sulfur of macroalgae and sewage sludge oils were observed compared to conventional bio-oil and this may limit their further industrial applications. The lignin char had a high proportion of small size particles, a HHV of 21 MJ/kg db and were almost free of chloride and sulfur, thus it is considered as a promising fuel for gasification or combustion; whereas macroalgae and sewage sludge chars containing high amounts of macronutrients as N, P, K, S, Mg and Ca and this could make the chars most valuable as raw materials for fertilizer production. The sewage sludge waste bulk volume (the char compared to the sludge) was reduced with 52 % by pyrolysis at 575 deg. C. It is seen that the fast pyrolysis process provides a promising method to reduce cost for landfilling and produce a bio-oil that can be used as a fuel. The pyrolysis temperature has a considerable effect on the product distributions of the lignin and sewage sludge PCR pyrolysis, as well as their bio-oil properties with respect to molecular mass distribution, identified GC-MS component compositions, water-insoluble fraction, viscosity, and HHV. A maximum of organic oil yields of lignin and sewage sludge PCR pyrolysis were obtained at optimal temperatures of 550 - 575 deg. C. In this work, the behaviors of slurry samples of wood, char and grinded char with respect to phase transitions, rheological properties, elemental composition, and energy density were investigated. Also pumping properties were investigated at temperatures of 25, 40 and 60 deg. C and the solids loading of 0 - 20 wt%. The bioslurries obtained a volume energy density of 21-23 GJ/m{sup 3} and an energy densification factor of 4.5 - 5 (when compared to beech wood). Their apparent viscosities were significantly influenced by the solid loading levels (0 - 20 wt %) and temperatures (25 - 60 deg. C). The slurry samples with 10 wt% char (having d80 of 276 {mu}m) and 20 wt% grinded char (having d80 of 118 {mu}m) were successfully pumped into a pressurized chamber (0 - 6 bar). (LN)

  8. Development of advanced technologies for biomass pyrolysis

    Science.gov (United States)

    Xu, Ran

    The utilization of biomass resources as a renewable energy resource is of great importance in responding to concerns over the protection of the environment and the security of energy supply. This PhD research focuses on the investigation of the conversion of negative value biomass residues into value-added fuels through flash pyrolysis. Pyrolysis Process Study. A pilot plant bubbling fluidized bed pyrolyzer has been set up and extensively used to thermally crack various low or negative value agricultural, food and biofuel processing residues to investigate the yields and quality of the liquid [bio-oil] and solid (bio-char] products. Another novel aspect of this study is the establishment of an energy balance from which the thermal self-sustainability of the pyrolysis process can be assessed. Residues such as grape skins and mixture of grape skins and seeds, dried distiller's grains from bio-ethanol plants, sugarcane field residues (internal bagasse, external and whole plant) have been tested. The pyrolysis of each residue has been carried out at temperatures ranging from 300 to 600°C and at different vapor residence times, to determine its pyrolysis behavior including yields and the overall energy balance. The thermal sustainability of the pyrolysis process has been estimated by considering the energy contribution of the product gases and liquid bio-oll in relation to the pyrolysis heat requirements. The optimum pyrolysis conditions have been identified in terms of maximizing the liquid blo-oil yield, energy density and content of the product blo-oil, after ensuring a self-sustainable process by utilizing the product gases and part of char or bio-oil as heat sources. Adownflow pyrolyzer has also been set up. Preliminary tests have been conducted using much shorter residence times. Bio-oil Recovery. Bio-oil recovery from the pyrolysis unit includes condensation followed by demisting. A blo-oil cyclonic condensing system is designed A nearly tangential entry forces the entering vapors and gases to spin, providing good heat transfer and driving the condensed droplets to the wall through cyclonic action. This condenser design has been successfully demonstrated for the application on the pilot fluidized bed pyrolysis unit. After condensation, a stable aerosol is also typically formed which is difficult to be efficiently captured with conventional technologies. A pilot scale helicoidal rotary demister, a novel technology for removing persistent fine bio-oil droplets from gases using dynamic centrifugal forces, has been developed. The demister uses a helicoidal element, which consists of a metal sheet wound as a spiral, designed to rotate at high speeds within a cyclone body. Larger droplets are separated as they enter the cyclone housing, while the smaller droplets are carried by the gas into the helicoidal path of the rotating element, where they are centrifuged towards the outer collecting walls and, as a result of a specially designed baffle, may flow counter-currently to the gas and are drained out from the bottom of the rotating element. The mist-free gas leaves through a channel located at the center of the spiral. This unique demister design has demonstrated a high separation efficiency when tested offline with artificial submicron mist and tested online for demisting bio-oil aerosol on the pyrolysis unit. Bio-oil Upgrading: Very often, phase separation of bio-oil occurs naturally upon condensation of the bio-oil vapors, typically through the use of cyclonic condensers. The bio-oil is separated into an organic phase and an aqueous phase. Research has been conducted on the possibility to enhance the fuel properties and energy performance of the organic phase by reducing its water content, enhancing its heating value and improving its stability. Through the use of drying agents, a remarkable reduction of water content and an increase of heating value can be achieved. Moreover, the volumetric energy density can be greatly enhanced. Besides, the energy yield of the process has also been investigated. (Abstract shortened by

  9. A Novel Energy-Efficient Pyrolysis Process: Self-pyrolysis of Oil Shale Triggered by Topochemical Heat in a Horizontal Fixed Bed

    Science.gov (United States)

    Sun, You-Hong; Bai, Feng-Tian; Lü, Xiao-Shu; Li, Qiang; Liu, Yu-Min; Guo, Ming-Yi; Guo, Wei; Liu, Bao-Chang

    2015-02-01

    This paper proposes a novel energy-efficient oil shale pyrolysis process triggered by a topochemical reaction that can be applied in horizontal oil shale formations. The process starts by feeding preheated air to oil shale to initiate a topochemical reaction and the onset of self-pyrolysis. As the temperature in the virgin oil shale increases (to 250-300°C), the hot air can be replaced by ambient-temperature air, allowing heat to be released by internal topochemical reactions to complete the pyrolysis. The propagation of fronts formed in this process, the temperature evolution, and the reaction mechanism of oil shale pyrolysis in porous media are discussed and compared with those in a traditional oxygen-free process. The results show that the self-pyrolysis of oil shale can be achieved with the proposed method without any need for external heat. The results also verify that fractured oil shale may be more suitable for underground retorting. Moreover, the gas and liquid products from this method were characterised, and a highly instrumented experimental device designed specifically for this process is described. This study can serve as a reference for new ideas on oil shale in situ pyrolysis processes.

  10. A novel energy-efficient pyrolysis process: self-pyrolysis of oil shale triggered by topochemical heat in a horizontal fixed bed.

    Science.gov (United States)

    Sun, You-Hong; Bai, Feng-Tian; Lü, Xiao-Shu; Li, Qiang; Liu, Yu-Min; Guo, Ming-Yi; Guo, Wei; Liu, Bao-Chang

    2015-01-01

    This paper proposes a novel energy-efficient oil shale pyrolysis process triggered by a topochemical reaction that can be applied in horizontal oil shale formations. The process starts by feeding preheated air to oil shale to initiate a topochemical reaction and the onset of self-pyrolysis. As the temperature in the virgin oil shale increases (to 250-300°C), the hot air can be replaced by ambient-temperature air, allowing heat to be released by internal topochemical reactions to complete the pyrolysis. The propagation of fronts formed in this process, the temperature evolution, and the reaction mechanism of oil shale pyrolysis in porous media are discussed and compared with those in a traditional oxygen-free process. The results show that the self-pyrolysis of oil shale can be achieved with the proposed method without any need for external heat. The results also verify that fractured oil shale may be more suitable for underground retorting. Moreover, the gas and liquid products from this method were characterised, and a highly instrumented experimental device designed specifically for this process is described. This study can serve as a reference for new ideas on oil shale in situ pyrolysis processes. PMID:25656294

  11. Bio-oil from Flash Pyrolysis of Agricultural Residues

    DEFF Research Database (Denmark)

    Ibrahim, Norazana

    2012-01-01

    This thesis describes the production of bio-oils from flash pyrolysis of agricultural residues, using a pyrolysis centrifugal reactor (PCR). By thermal degradation of agricultural residues in the PCR, a liquid oil, char and non-condensable gases are produced. The yield of each fraction is influenced by the reaction temperature and by feedstock ash composition. It have been the objective of the present work to investigate the influence of changed operation conditions on the yield of bio-oil, char and gas; as well as to investigate the composition and storage properties of some of the produced bio-oils. Mainly the influence of feedstock type (wheat straw, rice husk and pine wood), feedstock water content and reactor temperature on the yield of char, bio-oil and gas were investigated. The storage stability of bio-oils with respect to changes in viscosity, water content and pH were investigated for straw and pine wood oil at different temperature and residence times. Temperature plays a major role in the pyrolysis process and it determines to a high degree the fate of the final product yields and also product composition. Higher temperature favors the formation of pyrolysis gas while lower temperatures increase the yield of char. Liquid oil, however increases with temperature up to certain point and thereafter it decreases at still higher temperature due to secondary cracking of the primary products. The presence of moisture in the feed stock may also influences the pyrolysis process. The influence of reaction temperature and the moisture content on the flash pyrolysis product yield has been reported in Paper I (Chapter 2). It was observed that the presence of moisture in the wheat straw with different moisture levels of 1.5 wt. %, 6.2 wt. % and 15.0 wt. % have shown no significant effect on the pyrolysis product distribution. The fraction of bio-oil, char and gases produced from pyrolysis of straw were in the range of 40-60 wt. %, 18-50 wt. % and 5-22 wt. %, respectively, regardless of the straw moisture levels. The optimal reaction temperature for the production of bio-oil was around 525 °C to 550 °C for all straw moisture contents. It was investigated how differences in biomass composition influence pyrolysis products yields and the composition of char and bio-oils. Details about this investigation are explained in Paper II (Chapter 3). The used pine wood had a low ash content (0.5 wt. %), the wheat straw an intermediate ash level (6.0 wt. %) and the rice husk a high ash level (13.6 wt. %). The highest alkali content, potassium (1.53 wt. %) are present in straw and the lowest potassium content level is observed in pine wood (0.04 wt. %). The feedstocks were pyrolyzed at reactor temperatures ranging from 475 to 575 oC. It was observed that the formation of char and gas is affected by the biomass alkali content. Increasing biomass alkali content caused an increased feedstock conversion at low temperature, a lower maximum liquid organic yield temperature and a lower maximum liquid organics yield. In addition, the chemical compositions of the bio-oils and the chars of the investigated feedstocks were also analyzed. The utilization of the pyrolysis oil in static combustion equipments such as boilers and turbine have shown that the suitability of the pyrolysis oil to substitute fossil fuel. However, several limitations still arise due to the instability of the pyrolysis oil that may cause problems with transport and storage. Pyrolysis oil contains more than hundred of chemical compounds and has a wide range of volatility (different boiling points). The stability and aging of bio-oils generated by bench scale pyrolysis of wheat straw and pine wood are discussed in Paper III (Chapter 4). It was found that the bio-oil from wheat straw shows better stability compared to the bio-oil from pine wood. In addition, both bio-oils are fairly stable stored in a closed container at room temperature for up to 130 days, with no phase separation and only small changes in physical properties were observed. The combustion behavior of pyrolysis

  12. A Direct, Biomass-Based Synthesis of Benzoic Acid: Formic Acid-Mediated Deoxygenation of the Glucose-Derived Materials Quinic Acid and Shikimic Acid

    Energy Technology Data Exchange (ETDEWEB)

    Arceo, Elena; Ellman, Jonathan; Bergman, Robert

    2010-05-03

    An alternative biomass-based route to benzoic acid from the renewable starting materials quinic acid and shikimic acid is described. Benzoic acid is obtained selectively using a highly efficient, one-step formic acid-mediated deoxygenation method.

  13. Pyrolysis oil from carbonaceous solid wastes in Malaysia

    International Nuclear Information System (INIS)

    The agro-industrial sector of Malaysia produces a huge amount of oil palm and paddy rice. These generate a significant amount of renewable biomass solid wastes in the forms of oil palm shell and rice husk. Apart from this a huge quantity of scrap tyre is generated from the country's faster increasing usage of transportation vehicles like motorcycle, car, bus and lorries. These wastes are producing pollution and disposal problems affecting the environment. Besides energy is not recovered efficiently from these waste resources. From the elemental composition and thermogravimetric analysis (TGA) studies of the wastes, it appeared that the wastes could be used for pyrolysis liquid oil production. Pyrolysis at present is deemed to be a potential method for the conversion of carbonaceous solid wastes into upgraded liquid products which can either be tried for liquid fuel or value-added chemical. A fluidized bed bench scale fast pyrolysis system was employed for this thermochemical conversion process of solid wastes. Silica sand was used as fluidized bed material and nitrogen gas as the fluidising medium. The products obtained were liquid oil, solid char and gas. The liquid oil and solid char were collected separately while the gas was flared. The maximum liquid product yield was found to vary with feedstock material fluidized bed temperature. The maximum liquid product yield was found to be 58, 53 and 40 wt. % of biomass fed at fluidized bed temperature at 500, 525 and 4500C respectively for oil palm shell, scrap tyre and rice husk. The solid char yield was 25, 36 and 53 wt. % of biomass fed at the condition of maximum liquid product yield for oil palm shell, scrap tyre and rice husk respectively. The oil products were subjected to FTIR, GC and GC/MS analysis for their group composition and detailed chemical compositions. The pyrolysis oil from scrap tyre was found to contain highest percentage of pure hydrocarbons (25 wt. % of total feed) with esters and oxygenated hydrocarbons containing silicone. The phenols were found to be maximum in case of oil palm shell pyrolysis oil (35 wt. % of total feed) with organic acids, alcohol, ketones and hydrocarbons. The pyrolysis oil from rice husk contained a maximum. percentage of ketones (28 wt. % of total feed) with acids, aldehydes, alcohol, phenols and hydrocarbons. Thus, the compounds were found to be prospectful for fuel and chemicals. The physical properties of the pyrolysis oils were presented and compared with typical wood pyrolysis oil. (Author)

  14. Chemistry of decomposition of freshwater wetland sedimentary organic material during ramped pyrolysis

    Science.gov (United States)

    Williams, E. K.; Rosenheim, B. E.

    2011-12-01

    Ramped pyrolysis methodology, such as that used in the programmed-temperature pyrolysis/combustion system (PTP/CS), improves radiocarbon analysis of geologic materials devoid of authigenic carbonate compounds and with low concentrations of extractable authochthonous organic molecules. The approach has improved sediment chronology in organic-rich sediments proximal to Antarctic ice shelves (Rosenheim et al., 2008) and constrained the carbon sequestration potential of suspended sediments in the lower Mississippi River (Roe et al., in review). Although ramped pyrolysis allows for separation of sedimentary organic material based upon relative reactivity, chemical information (i.e. chemical composition of pyrolysis products) is lost during the in-line combustion of pyrolysis products. A first order approximation of ramped pyrolysis/combustion system CO2 evolution, employing a simple Gaussian decomposition routine, has been useful (Rosenheim et al., 2008), but improvements may be possible. First, without prior compound-specific extractions, the molecular composition of sedimentary organic matter is unknown and/or unidentifiable. Second, even if determined as constituents of sedimentary organic material, many organic compounds have unknown or variable decomposition temperatures. Third, mixtures of organic compounds may result in significant chemistry within the pyrolysis reactor, prior to introduction of oxygen along the flow path. Gaussian decomposition of the reaction rate may be too simple to fully explain the combination of these factors. To relate both the radiocarbon age over different temperature intervals and the pyrolysis reaction thermograph (temperature (°C) vs. CO2 evolved (?mol)) obtained from PTP/CS to chemical composition of sedimentary organic material, we present a modeling framework developed based upon the ramped pyrolysis decomposition of simple mixtures of organic compounds (i.e. cellulose, lignin, plant fatty acids, etc.) often found in sedimentary organic material to account for changes in thermograph shape. The decompositions will be compositionally verified by 13C NMR analysis of pyrolysis residues from interrupted reactions. This will allow for constraint of decomposition temperatures of individual compounds as well as chemical reactions between volatilized moieties in mixtures of these compounds. We will apply this framework with 13C NMR analysis of interrupted pyrolysis residues and radiocarbon data from PTP/CS analysis of sedimentary organic material from a freshwater marsh wetland in Barataria Bay, Louisiana. We expect to characterize the bulk chemical composition during pyrolysis and as well as diagenetic changes with depth. Most importantly, we expect to constrain the potential and the limitations of this modeling framework for application to other depositional environments.

  15. Pyrolysis characteristic of tobacco stem studied by Py-GC/MS, TG-FTIR, and TG-MS

    Directory of Open Access Journals (Sweden)

    Bei Liu

    2013-02-01

    Full Text Available Pyrolysis characteristics and mechanism of tobacco stem were studied by pyrolysis coupled with gas chromatography/mass spectrometry (Py-GC/MS, thermogravimetric analyzer coupled with Fourier transform infrared spectrometry, and mass spectrometry (TG-FTIR and TG-MS techniques. The composition of evolved volatiles from fast pyrolysis of tobacco stem was determined by Py-GC/MS analysis, and the evolution patterns of the major products were investigated by TG-FTIR and TG-MS. Py-GC/MS data indicated that furfural and phenol were the major products in low temperature pyrolysis, and these were generated from depolymerization of cellulose. Indene and naphthalene were the major products in high temperature pyrolysis. TG-FTIR and TG-MS results showed that CO, CO2, phenols, aldehydes, and ketones were released between 167ºC and 500ºC; at temperatures >500ºC, CO and CO2 were the main gaseous products.

  16. Influence of Pyrolysis Parameters on the Performance of CMSM

    Directory of Open Access Journals (Sweden)

    Marta C. Campo

    2009-01-01

    Full Text Available Carbon hollow fiber membranes have been prepared by pyrolysis of a P84/S-PEEK blend. Proximate analysis of the precursor was performed using thermogravimetry (TGA, and a carbon yield of approximately 40% can be obtained. This study aimed at understanding the influence of pyrolysis parameters—end temperature, quenching effect, and soaking time—on the membrane properties. Permeation experiments were performed with N2, He, and CO2. Scanning electron microscopy (SEM has been done for all carbon hollow fibers. The highest permeances were obtained for the membrane submitted to an end temperature of 750°C and the highest ideal selectivities for an end temperature of 700°C. In both cases, the membranes were quenched to room temperature.

  17. Mild pyrolysis of P3HB/Switchgrass blends for the production of bio-oil enriched with crotonic acid

    Science.gov (United States)

    The mild pyrolysis of switchgrass/poly-3-hydroxybutyrate (P3HB) blends that mimic P3HB-producing switchgrass lines was studied in a pilot scale fluidized bed reactor with the goal of simultaneously producing crotonic acid and switchgrass-based bio-oil. Factors such as pyrolysis temperature, residenc...

  18. Homocoupling versus reduction of radicals: an experimental and theoretical study of Ti(III)-mediated deoxygenation of activated alcohols.

    Science.gov (United States)

    Prieto, Consuelo; González Delgado, José A; Arteaga, Jesús F; Jaraíz, Martín; López-Pérez, José L; Barrero, Alejandro F

    2015-03-21

    A detailed experimental and theoretical study corroborates that the reductive deoxygenation of activated (allylic or benzylic) alcohols with excess Ti(III) proceeds via an allyl(benzyl)-radical and allyl(benzyl)-Ti, which is protonated, regioselectively in the case of allylic derivatives. The H atom of the newly formed C-H bond in the product originates from the -OH group of the starting material. The deoxygenation of lithium alkoxides or alcohols by using 1.0 mol of Ti(III) leads to the corresponding dimerization products in good yields. An excellent agreement with the experimental data was obtained by using a reaction kinetics simulator to discriminate between competing reactions. PMID:25665946

  19. Co-pyrolysis of low rank coals and biomass: Product distributions

    Energy Technology Data Exchange (ETDEWEB)

    Soncini, Ryan M; Means, Nicholas C; Weiland, Nathan T

    2013-10-01

    Pyrolysis and gasification of combined low rank coal and biomass feeds are the subject of much study in an effort to mitigate the production of green house gases from integrated gasification combined cycle (IGCC) systems. While co-feeding has the potential to reduce the net carbon footprint of commercial gasification operations, the effects of co-feeding on kinetics and product distributions requires study to ensure the success of this strategy. Southern yellow pine was pyrolyzed in a semi-batch type drop tube reactor with either Powder River Basin sub-bituminous coal or Mississippi lignite at several temperatures and feed ratios. Product gas composition of expected primary constituents (CO, CO{sub 2}, CH{sub 4}, H{sub 2}, H{sub 2}O, and C{sub 2}H{sub 4}) was determined by in-situ mass spectrometry while minor gaseous constituents were determined using a GC-MS. Product distributions are fit to linear functions of temperature, and quadratic functions of biomass fraction, for use in computational co-pyrolysis simulations. The results are shown to yield significant nonlinearities, particularly at higher temperatures and for lower ranked coals. The co-pyrolysis product distributions evolve more tar, and less char, CH{sub 4}, and C{sub 2}H{sub 4}, than an additive pyrolysis process would suggest. For lignite co-pyrolysis, CO and H{sub 2} production are also reduced. The data suggests that evolution of hydrogen from rapid pyrolysis of biomass prevents the crosslinking of fragmented aromatic structures during coal pyrolysis to produce tar, rather than secondary char and light gases. Finally, it is shown that, for the two coal types tested, co-pyrolysis synergies are more significant as coal rank decreases, likely because the initial structure in these coals contains larger pores and smaller clusters of aromatic structures which are more readily retained as tar in rapid co-pyrolysis.

  20. Catalytic oxidative pyrolysis of spent organic ion exchange resins from nuclear power plants

    International Nuclear Information System (INIS)

    The spent IX resins from nuclear power reactors are highly active solid wastes generated during operations of nuclear reactors. Catalytic oxidative pyrolysis of these resins can lead to high volume reduction of these wastes. Low temperature pyrolysis of transition metal ion loaded IX resins in presence of nitrogen was carried out in order to optimize catalyst composition to achieve maximum weight reduction. Thermo gravimetric analysis of the pyrolysis residues was carried out in presence of air in order to compare the oxidative characteristics of transition metal oxide catalysts. Copper along with iron, chromium and nickel present in the spent IX resins gave the most efficient catalyst combination for catalytic and oxidative pyrolysis of the residues. During low temperature catalytic pyrolysis, 137Cesium volatility was estimated to be around 0.01% from cationic resins and around 0.1% from anionic resins. During oxidative pyrolysis at 700 degC, nearly 10 to 40% of 137Cesium was found to be released to off gases depending upon type of resin and catalyst loaded on to it. The oxidation of pyrolytic residues at 700 degC gave weight reduction of 15% for cationic resins and 93% for anionic resins. Catalytic oxidative pyrolysis is attractive for reducing weight and volume of spent cationic resins from PHWRs and VVERs. (author)

  1. Pyrolysis of polyolefins for increasing the yield of monomers' recovery.

    Science.gov (United States)

    Donaj, Pawel J; Kaminsky, W; Buzeto, F; Yang, W

    2012-05-01

    Pyrolysis of plastic waste is an alternative way of plastic recovery and could be a potential solution for the increasing stream of solid waste. The objective of this work was to increase the yield the gaseous olefins (monomers) as feedstock for polymerization process and to test the applicability of a commercial Ziegler-Natta (Z-N): TiCl(4)/MgCl(2) for cracking a mixture of polyolefins consisted of 46%wt. of low density polyethylene (LDPE), 30%wt. of high density polyethylene (HDPE) and 24%wt. of polypropylene (PP). Two sets of experiments have been carried out at 500 and 650°C via catalytic pyrolysis (1% of Z-N catalyst) and at 650 and 730°C via only-thermal pyrolysis. These experiments have been conducted in a lab-scale, fluidized quartz-bed reactor of a capacity of 1-3kg/h at Hamburg University. The results revealed a strong influence of temperature and presence of catalyst on the product distribution. The ratios of gas/liquid/solid mass fractions via thermal pyrolysis were: 36.9/48.4/15.7%wt. and 42.4/44.7/13.9%wt. at 650 and 730°C while via catalytic pyrolysis were: 6.5/89.0/4.5%wt. and 54.3/41.9/3.8%wt. at 500 and 650°C, respectively. At 650°C the monomer generation increased by 55% up to 23.6%wt. of total pyrolysis products distribution while the catalyst was added. Obtained yields of olefins were compared with the naphtha steam cracking process and other potentially attractive processes for feedstock generation. The concept of closed cycle material flow for polyolefins has been discussed, showing the potential benefits of feedstock recycling in a plastic waste management. PMID:22093704

  2. The effect of coal type and pyrolysis temperature on the electrochemical activity of coal at a solid carbon anode in molten carbonate media

    Science.gov (United States)

    Allen, J. A.; Glenn, M.; Donne, S. W.

    2015-04-01

    A systematic assessment of the electrochemical activity of two different parent coal types, pyrolysed at temperatures between 500 and 900 °C higher heating temperature (HHT), is presented in this work. Analysis shows that certain coal chars are catalytically activated in molten carbonate media at 600 °C, however activity does not appear to follow trends established for ashless carbon sources. It is seen here that it is not possible to predict activity based solely on electrical resistance, surface functionalization, or the BET surface area of pyrolysed coals. Instead, it is suggested that coal ash type, abundance and distribution plays a pivotal role in activating the coal char to allow fast electrochemical oxidation through a catalytically enhanced pathway. Activation from ash influence is discussed to result from wetting of the molten carbonate media with the carbon surface (change in polarity of electrode surface), through ash mediated oxide adsorption and transfer to carbon particles, or possibly through another catalytic pathway not yet able to be predicted from current results.

  3. Probing the Thermal Deoxygenation of Graphene Oxide using High Resolution In Situ X-Ray based Spectroscopies

    OpenAIRE

    Ganguly, Abhijit; Sharma, Surbhi; Papakonstantinou, Pagona; Hamilton, Jeremy

    2011-01-01

    Despite the recent developments in Graphene Oxide due to its importance as a host precursor of Graphene, the detailed electronic structure and its evolution during the thermal reduction remain largely unknown, hindering its potential applications. We show that a combination of high resolution in situ X-ray photoemission and X-ray absorption spectroscopies offer a powerful approach to monitor the deoxygenation process and comprehensively evaluate the electronic structure of G...

  4. Tuning the Selectivity in Deoxygenation of Triglycerides Aimed at the production of Renewable Feedstocks for Ethylene Production.

    Czech Academy of Sciences Publication Activity Database

    Kubi?ka, D.; Horá?ek, J.; Kaluža, Lud?k

    Jerusalem : -, 2009, s. 424. ISBN N. [EuropaCat IX: "Catalysis for Sustainable World". Salamanca (ES), 30.08.2009-04.09.2009] R&D Projects: GA MPO FT-TA3/074 Institutional research plan: CEZ:AV0Z40720504 Keywords : deoxygenation * NiMo catalysts * biofuel Subject RIV: CC - Organic Chemistry http://www.certh.gr/577CC7CC.en.aspx

  5. Pyrolysis of a waste from the grinding of scrap tyres

    International Nuclear Information System (INIS)

    Highlights: ? The pyrolysis of reinforcing fibres obtained from scrap tyres has been studied. ? The results have been compared to scrap tyre granules. ? A higher temperature is needed for the total decomposition of the fibres. ? More compounds with heteroatoms (O, N) were found in the oil from the fibres. ? Chars from the fibres exhibit lower BET surface and mesopore volume. - Abstract: The fibres that are used to reinforce tyres can be recovered as a waste in the process of grinding of scrap tyres. In this paper beneficiation through pyrolysis is studied since the fibres are made up of polymers with a small amount of rubber because the latter is difficult to separate. The experiments were performed at three temperatures (400, 550 and 900 °C) in a horizontal oven. The three products – gas, oil and char – obtained from the pyrolysis were investigated. The composition of the gas was analyzed by means of gas chromatography. The oil was studied by gas chromatography and infrared spectroscopy. The char porous structure was determined by N2 adsorption. In addition, the topography of the chars was studied by means of scanning electron microscopy (SEM). The products resulting from the pyrolysis of the fibres were compared with those obtained from scrap rubber.

  6. The release of nitrogen in coal combustion and pyrolysis

    International Nuclear Information System (INIS)

    Environmental aspects of coal utilization are a major concern. Recent advances in the development of low NOx burners and the emerging technologies of fluidized bed combustion have led to the identification of coal char nitrogen as the major contributor to the nitrogen oxides released during combustion. The temperature programmed combustion and pyrolysis of a series of coals covering a wide range of rank have been investigated. In addition, maceral concentrates have been investigated to assess the variation in the combustion behavior and the release of nitrogen in the pyrolysis and combustion of macerals. This investigation has involved the use of thermogravimetric analysis - mass spectrometry (TG-MS) with two sampling options: (1) ?1cm from the sample and (2) at the exit of the TG. The former allows reactive species to be identified in the combustion of the coals. These temperature programmed combustion results have been compared with similar measurements carried out at the exit of the TG where the products are at equilibrium. In addition, pyrolysis studies have been carried out under similar conditions. The results show that reactive intermediate species such as HCN, (CN)2, COS etc. can be detected in the combustion products. The evolution of these species during combustion are compared with the pyrolysis products of the coal. The results are discussed in relation to the structure of the coals and the conversion of volatile species and char ninversion of volatile species and char nitrogen to nitrogen oxides

  7. Deactivation in Continuous Deoxygenation of C18-Fatty Feedstock over Pd/Sibunit

    DEFF Research Database (Denmark)

    Madsen, Anders Theilgaard; Rozmys?owicz, Bartosz

    2013-01-01

    Catalytic continuous deoxygenation of stearic acid, ethyl stearate and tristearin without any solvents was investigated using Pd/Sibunit as a catalyst in a trickle bed reactor at 300 °C. The main emphasis was to investigate the effect of gas atmosphere and catalyst deactivation. In addition to liquid-phase analysis made offline by GC, also online gas-phase analysis with IR were performed. The main liquid-phase product coming from all reactants was n-heptadecane. In addition to deoxygenation, which was observed for all substrates, also C18 and C16 alkanes were formed from tristearin. The relative ratios between stearic acid, ethyl stearate and tristearin conversions to alkanes after 3 days time-on-stream were 2.8/2.3/1.0, respectively using 5 % H2/Ar as a gas atmosphere, whereas rapid catalyst deactivation occurred with all substrates under H2-lacking atmosphere. The spent catalyst’s specific surface area profile along the downward reactor was maximum in the middle of the catalyst beds with the highest pore shrinking in the beginning and at the end of the reactor catalyst segments in the case of stearic acid and tristearin deoxygenation whereas that decreased consecutively as ethyl stearate passed through the reactor.

  8. Studies on steam pyrolysis of amides as a waste solvent management method

    International Nuclear Information System (INIS)

    A laboratory scale pyrolysis reactor set-up was designed and constructed. The steam pyrolysis of dimethyl formamide (DMF) was studied in a tubular flow reactor at atmospheric pressure. The experimental data were obtained at a temperature range of 500-1100 deg C for different flow rates and steam to amide mass ratio. The reaction products were analyzed by gas chromatography and high pressure liquid chromatography. The experimental data was analyzed using a power law model to estimate apparent rate constant and corresponding activation energy. A reaction network model is being developed to include reaction mechanism of steam pyrolysis. (author)

  9. Methods and apparatuses for preparing upgraded pyrolysis oil

    Science.gov (United States)

    Brandvold, Timothy A; Baird, Lance Awender; Frey, Stanley Joseph

    2013-10-01

    Methods and apparatuses for preparing upgraded pyrolysis oil are provided herein. In an embodiment, a method of preparing upgraded pyrolysis oil includes providing a biomass-derived pyrolysis oil stream having an original oxygen content. The biomass-derived pyrolysis oil stream is hydrodeoxygenated under catalysis in the presence of hydrogen to form a hydrodeoxygenated pyrolysis oil stream comprising a cyclic paraffin component. At least a portion of the hydrodeoxygenated pyrolysis oil stream is dehydrogenated under catalysis to form the upgraded pyrolysis oil.

  10. Study on the combined sewage sludge pyrolysis and gasification process: mass and energy balance.

    Science.gov (United States)

    Wang, Zhonghui; Chen, Dezhen; Song, Xueding; Zhao, Lei

    2012-12-01

    A combined pyrolysis and gasification process for sewage sludge was studied in this paper for the purpose of its safe disposal with energy self-balance. Three sewage sludge samples with different dry basis lower heat values (LHV(db)) were used to evaluate the constraints on this combined process. Those samples were pre-dried and then pyrolysed within the temperature range of 400-550 degrees C. Afterwards, the char obtained from pyrolysis was gasified to produce fuel gas. The experimental results showed that the char yield ranged between 37.28 and 53.75 wt% of the dry sludge and it changed with ash content, pyrolysis temperature and LHV(db) of the sewage sludge. The gas from char gasification had a LHV around 5.31-5.65 MJ/Nm3, suggesting it can be utilized to supply energy in the sewage sludge drying and pyrolysis process. It was also found that energy balance in the combined process was affected by the LHV(db) of sewage sludge, moisture content and pyrolysis temperature. Higher LHV(db), lower moisture content and higher pyrolysis temperature benefit energy self-balance. For sewage sludge with a moisture content of 80 wt%, LHV(db) of sewage sludge should be higher than 18 MJ/kg and the pyrolysis temperature should be higher than 450 degrees C to maintain energy self-sufficiency when volatile from the pyrolysis process is the only energy supplier; when the LHV(db) was in the range of 14.65-18 MJ/kg, energy self-balance could be maintained in this combined process with fuel gas from char gasification as a supplementary fuel; auxiliary fuel was always needed if the LHV(db) was lower than 14.65 MJ/kg. PMID:23437644

  11. Quantification of ischemic muscle deoxygenation by near infrared time-resolved spectroscopy

    Science.gov (United States)

    Hamaoka, Takatumi; Katsumura, Toshihito; Murase, Norio; Nishio, Shinya; Osada, Takuya; Sako, Takayuki; Higuchi, Hiroyuki; Kurosawa, Yuko; Shimomitsu, Teruichi; Miwa, Mitsuharu; Chance, Britton

    2000-01-01

    The purpose of this study was to quantify muscle deoxygenation in human skeletal muscles using near infrared time-resolved spectroscopy (NIRTRS) and compare NIRTRS indicators and blood saturation. The forearm muscles of five healthy males (aged 27 - 32 yrs.) were monitored for changes in hemoglobin saturation (SO2) during 12 min of arterial occlusion and recovery. SO2 was determined by measuring the temporal profile of photon diffusion at 780 and 830 nm using NIRTRS, and was defined as SO2-TRS. Venous blood samples were also obtained for measurements of SvO2, and PvO2. Interstitial PO2(PintO2) was monitored by placing an O2 electrode directly into the muscle tissue. Upon the initiation of occlusion, all parameters fell progressively until reaching a plateau in the latter half of occlusion. It was observed at the end of occlusion that SO2-TRS (24.1 +/- 5.6%) agreed with SvO2 (26.2 +/- 6.4) and that PintO2 (14.7 +/- 1.0 Torr) agreed with PvO2 (17.3 +/- 2.2 Torr). The resting O2 store (oxygenated hemoglobin) and O2 consumption rate were 290 (mu) M and 0.82 (mu) Ms-1, respectively, values which reasonably agree with the reported results. These results indicate that there was no O2 gradient between vessels and interstisium at the end of occlusion.

  12. Exploratory studies on fast pyrolysis oil upgrading

    OpenAIRE

    Mahfud, Farchad Husein,

    2007-01-01

    Pyrolysis oil is a dark brown liquid which can be produced in high yield from different kind of biomass sources by means of fast pyrolysis. Pyrolysis oil is considered as a promising second generation energy carrier and may play an important role in the future of "biobased economies". The energy content of pyrolysis oil is approximately half of fossil crude. Just like for crude oil, further reprocessing is necessary to arranged pyrolysis oil as fuel in e.g. combustion engines. This thesis des...

  13. Development of a high-performance, coal-fired power generating system with a pyrolysis gas and char-fired high-temperature furnace

    Energy Technology Data Exchange (ETDEWEB)

    Shenker, J.

    1995-11-01

    A high-performance power system (HIPPS) is being developed. This system is a coal-fired, combined-cycle plant that will have an efficiency of at least 47 percent, based on the higher heating value of the fuel. The original emissions goal of the project was for NOx and SOx to each be below 0.15 lb/MMBtu. In the Phase 2 RFP this emissions goal was reduced to 0.06 lb/MMBtu. The ultimate goal of HIPPS is to have an all-coal-fueled system, but initial versions of the system are allowed up to 35 percent heat input from natural gas. Foster Wheeler Development Corporation is currently leading a team effort with AlliedSignal, Bechtel, Foster Wheeler Energy Corporation, Research-Cottrell, TRW and Westinghouse. Previous work on the project was also done by General Electric. The HIPPS plant will use a high-Temperature Advanced Furnace (HITAF) to achieve combined-cycle operation with coal as the primary fuel. The HITAF is an atmospheric-pressure, pulverized-fuel-fired boiler/air heater. The HITAF is used to heat air for the gas turbine and also to transfer heat to the steam cycle. its design and functions are very similar to conventional PC boilers. Some important differences, however, arise from the requirements of the combined cycle operation.

  14. Characteristics of SnO2:F Thin Films Deposited by Ultrasonic Spray Pyrolysis: Effect of Water Content in Solution and Substrate Temperature

    Directory of Open Access Journals (Sweden)

    Mario A. Sánchez-García

    2012-10-01

    Full Text Available Fluorine doped tin oxide, SnO2:F, thin films were deposited by ultrasonic chemical spray starting from tin chloride and hydrofluoric acid. The physical characteristics of the films as a function of both water content in the starting solution and substrate temperature were studied. The film structure was polycrystalline in all cases, showing that the intensity of (200 peak increased with the water content in the starting solution. The electrical resistivity decreased with the water content, reaching a minimum value, in the order of 8 ? 10-4 ?cm, for films deposited at 450? from a starting solution with a water content of 10 ml per 100 ml of solution; further increase in water content increased the corresponding resistivity. Optical transmittances of SnO2:F films were high, in the order of 75%, and the band gap values oscillated around 3.9 eV. SEM analysis showed uniform surface morphologies with different geometries depending on the deposition conditions. Composition analysis showed a stoichiometric compound with a [Sn/O] ratio around 1:2 in all samples. The presence of F into the SnO2 lattice was detected, within 2 at % respect to Sn.

  15. Multicomponent ceramic powder generation by spray pyrolysis

    International Nuclear Information System (INIS)

    This paper reports that the authors examined methods for controlling the morphology and microstructure of ceramic particles produced by spray pyrolysis. A variety of materials were examined including SrTiO3 and BaTiO3 and the oxides of Al, Mg, Zn, Pd, V, Mo, and Bi. The morphology of the particles was influenced by using colloidal precursors in combination with molecular precursors for particle generation. Slow drying rates obtained by using high relative humidities and controlled axial temperature gradients did not influence particle morphology for the systems and conditions studied. The microstructure of Al2O3, Bi2O3, V2O5, and PdO particles was controlled by varying the temperature to provide nanocrystalline or single-crystal particles. Evaporation and condensation of volatile species such as MoO3 and V2O5 dramatically modified particle microstructure and morphology

  16. Bio-oil production through pyrolysis of blue-green algae blooms (BGAB): Product distribution and bio-oil characterization

    International Nuclear Information System (INIS)

    Pyrolysis experiments of blue-green algae blooms (BGAB) were carried out in a fixed-bed reactor to determine the effects of pyrolysis temperature, particle size and sweep gas flow rate on pyrolysis product yields and bio-oil properties. The pyrolysis temperature, particle size and sweep gas flow rate were varied in the ranges of 300–700 °C, below 0.25–2.5 mm and 50–400 mL min?1, respectively. The maximum oil yield of 54.97% was obtained at a pyrolysis temperature of 500 °C, particle size below 0.25 mm and sweep gas flow rate of 100 mL min?1. The elemental analysis and calorific value of the oil were determined, and the chemical composition of the oil was investigated using gas chromatography–mass spectroscopy (GC–MS) technique. The analysis of bio-oil composition showed that bio-oil from BGAB could be a potential source of renewable fuel with a heating value of 31.9 MJ kg?1. - Highlights: ? Bio-oil production from pyrolysis of blue-green algae blooms in fixed bed reactor. ? Effects of pyrolysis conditions on product distribution were investigated. ? The maximum bio-oil yield reached 54.97 wt %. ? The bio-oil has high heating value and may be suitable as renewable fuel. ? Pyrolysis of algal biomass beneficial for energy recovery, eutrophication control

  17. Pyrolysis of hydrocarbons in hydrogen and deuterium plasma jets Pt. 1

    International Nuclear Information System (INIS)

    The pyrolysis of methane in high temperature atmospheric pressure hydrogen and deuterium plasma jets has been studied. Product distributions at different temperatures and conversion levels have been determined. The highest value for acetylene formation selectivity found was around 90%, the rest being converted practically to ethylene. All the pyrolysis product components obtained in experiments carried out in deuterium plasma contained deuterium; this finding provided for the first time the experimental proof that pyrolysis reactions of methane in a hydrogen plasma jet are of the radical type and, additionally it proved that the components of the hydrogen plasma - hydrogen atoms and molecules - play a role also as reactants in hydrocarbon plasma pyrolysis. Reaction path schemes have been developed based on the deuterium distribution found in the reaction products. (author)

  18. The production and evaluation of bio-oils from the pyrolysis of sunflower-oil cake

    Energy Technology Data Exchange (ETDEWEB)

    Gercel, Hasan Ferdi [Anadolu Univ., Dept. of Chemical Engineering, Eskisehir (Turkey)

    2002-10-01

    Sunflower (Helianthus annus L.)-oil cake pyrolysis experiments were achieved in a fixed-bed tubular reactor. The effects of nitrogen flow rate and final pyrolysis temperature on the pyrolysis product yields and chemical compositions have been investigated. The maximum bio-oil yield of 48.69 wt% was obtained in nitrogen atmosphere with nitrogen flow rate of 100 cm{sup 3} min{sup -1} and at a pyrolysis temperature of 550 deg C with a heating rate of 5 deg Cs{sup -1}. Chromatographic and spectroscopic studies on the pyrolytic oil showed that the oil obtained from sunflower-oil cake can be used as a renewable fuel and chemical feedstocks. (Author)

  19. Making Activated Carbon by Wet Pressurized Pyrolysis

    Science.gov (United States)

    Fisher, John W.; Pisharody, Suresh; Wignarajah, K.; Moran, Mark

    2006-01-01

    A wet pressurized pyrolysis (wet carbonization) process has been invented as a means of producing activated carbon from a wide variety of inedible biomass consisting principally of plant wastes. The principal intended use of this activated carbon is room-temperature adsorption of pollutant gases from cooled incinerator exhaust streams. Activated carbon is highly porous and has a large surface area. The surface area depends strongly on the raw material and the production process. Coconut shells and bituminous coal are the primary raw materials that, until now, were converted into activated carbon of commercially acceptable quality by use of traditional production processes that involve activation by use of steam or carbon dioxide. In the wet pressurized pyrolysis process, the plant material is subjected to high pressure and temperature in an aqueous medium in the absence of oxygen for a specified amount of time to break carbon-oxygen bonds in the organic material and modify the structure of the material to obtain large surface area. Plant materials that have been used in demonstrations of the process include inedible parts of wheat, rice, potato, soybean, and tomato plants. The raw plant material is ground and mixed with a specified proportion of water. The mixture is placed in a stirred autoclave, wherein it is pyrolized at a temperature between 450 and 590 F (approximately between 230 and 310 C) and a pressure between 1 and 1.4 kpsi (approximately between 7 and 10 MPa) for a time between 5 minutes and 1 hour. The solid fraction remaining after wet carbonization is dried, then activated at a temperature of 500 F (260 C) in nitrogen gas. The activated carbon thus produced is comparable to commercial activated carbon. It can be used to adsorb oxides of sulfur, oxides of nitrogen, and trace amounts of hydrocarbons, any or all of which can be present in flue gas. Alternatively, the dried solid fraction can be used, even without the activation treatment, to absorb oxides of nitrogen.

  20. Study of the experimental conditions of the co-pyrolysis of rice husk and plastic wastes

    OpenAIRE

    Costa, Paula; Pinto, Filomena; Miranda, Miguel; André, Rui Neto

    2014-01-01

    The main objective of this study is to access the technical and economical viability of using pyrolysis technology applied to the rice production main wastes to produce bio-fuels to substitute fossil fuels and electricity consumption during rice milling processes. Therefore, it was studied the effect of operating conditions (reaction temperature, initial pressure and reaction time) on products yields and quality, as well as the possible synergetic effects that may occur during the pyrolysis o...

  1. Spray pyrolysis of CZTS nanoplatelets.

    Science.gov (United States)

    Exarhos, S; Bozhilov, K N; Mangolini, L

    2014-10-01

    We demonstrate that copper-zinc-tin-sulphide nanoplatelets can be directly grown onto a molybdenum-coated substrate using spray pyrolysis starting from a mixture of metal thiocarbamates precursors. The structure and phase purity of the nanoplatelets is discussed in detail. PMID:25119262

  2. Research into fine powder and large particle tyre pyrolysis.

    Science.gov (United States)

    Gao, Ningbo; Li, Aimin; Li, Wanjing

    2009-05-01

    This paper investigates the kinetics of the pyrolysis of scrap tyre using thermogravimetry and a small batch laboratory-scale externally heated fixed-bed. Five particle sizes (20-40, 40-60, 60-80, 80-100, 100-200 mesh) and five heating rates (5, 10, 15, 20, 40 K min(-1)) were investigated. The results show that there is no obvious distinction on weight loss for different sizes. With increasing heating rate the weight loss regions shift to a higher temperature range and the weight loss rate increases. The activation energy (E) and pre-exponential factor constant (A) were calculated using the Arrhenius type kinetic model. The heat value of pyrolysis gases is in the range of 12 to 22 MJ Nm(-3). The yields of solid, liquid and gas of pyrolysis scrap tyre and tyre cube at 800 degrees C were investigated, the ratio of pyrolysis production composition of scrap tyre and tyre cube for gas, oil and char is found to be 35 : 23 : 42 and 10 : 31 : 59, respectively. PMID:19423576

  3. Fixed bed pyrolysis of Euphorbia rigida with different catalysts

    International Nuclear Information System (INIS)

    Since Euphorbia rigida is a celluloid plant with low fat content, the oil yields of previous fixed bed pyrolysis studies were low. In order to increase the oil yield, biomass pyrolysis experiments were performed in a fixed bed reactor with two selected commercial catalysts, namely Criterion-534 and activated alumina, and natural zeolite (klinoptilolite). Experiments were conducted in a static atmosphere with a heating rate of 7 deg. C min-1, pyrolysis temperature of 550 deg. C and mean particle size of 0.55 mm. In the experiments, all the catalysts were used with various percentages, and the effects of the variable catalysts on the yields and chemical composition of the oils obtained were investigated. Oil yield reached 27.5% with the use of natural zeolite, 31% with Criterion-534 and 28.1% with activated alumina, while it was only 21.6% without a catalyst. The pyrolysis oils were examined by using spectroscopic and chromatographic analysis techniques, and the obtained results were compared with the results of similar experiments achieved without a catalyst

  4. Applied thermal pyrolysis of cogongrass in twin screw reactor

    Science.gov (United States)

    Promdee, K.; Vitidsant, T.

    2014-08-01

    Thermal pyrolysis by heat transfer model can be solved the control temperature in twin screw feeder for produce bio-oil from Cogongrass by novel continuous pyrolysis reactor. In this study, all yield were expressed on a dry and their values were taken as the average of the thermal controlled. Thermal of pyrolysis were carried out at 400-500°C. The products yield calculation showed that the liquid yield of Cogongrass by pyrolysis was higher than that solid and gas yield, as highest of 52.62%, at 500°C, and the other of liquid yield obtained from Cogongrass were 40.56, and 46.45%, at 400, and 450°C, respectively. When separate liquid phase be composed of the bio-oil was highest 37.39%, at 500°C. Indicated that biomass from Cogongrass had good received yields because of low solid yield average and gas yield and high liquid yield average. The compounds detected in bio-oil from Cogongrass showed the functional group, especially; Phenol, Phenol 2,5-dimethyl, Benzene 1-ethyl-4-methoxy, 2-Cyclopenten-1-one, 2,3-dimethyl, Benzene 1-ethyl-3-methyl.

  5. Pyrolysis of thermally thick wood particles - experiments and mathematical modelling

    Energy Technology Data Exchange (ETDEWEB)

    Moeller Andersen, S.; Thaaning Pedersen, S.; Goebel, B.; Houbak, N.; Henriksen, Ulrik [MEK - DTU, Kgs. Lyngby (Denmark); Dall Bentzen, J. [COWI a/s, Kgs. Lyngby (Denmark)

    2005-07-01

    A simple, dynamic, l-dimensional model describing heating, drying and pyrolysis of thermally thick wood particles with a l-dimensional geometry has been developed and implemented. The model output is the dynamic evolution of both the char yield and the amount of volatiles. The model is developed in such a simple and accessible way, that it easily can be implemented in a larger model for dimensioning and optimisation of applications where pyrolysis is a part of the overall process as for instance gasification. Experiments using a Thermo Gravimetric Analyser (TGA), built so pieces of wood can be fed into a hot atmosphere instantaneously, have been used to observe the influence of various parameters like temperature and size and wood types on the pyrolysis process. Results from the model have been compared with results from the experiments. The comparison showed good accordance when both wood particles with a well-defined geometry (a cylinder) and when beds of wood chips and wood pellets, respectively, were pyrolyzed. The model has proven that transport of heat to the wood; internal transport and accumulation of heat inside the wood and kinetics of pyrolysis are all important parameters. (au)

  6. Supercritical pyrolysis of the endothermic fuels methylcyclohexane, decalin, and tetralin

    Science.gov (United States)

    Stewart, John Francis

    The pyrolysis of the potential endothermic fuels methylcyclohexane, decahydronaphthalene (decalin), and tetrahydronaphthalene (tetralin) under supercritical conditions can be of great import and is the focus of this dissertation. Supercritical fluids, essentially gases with a liquid-like density, are a unique environment for chemical kinetic studies. Because the solvent properties of a supercritical fluid vary strongly with pressure (unlike liquids or gases), elementary reactions in a supercritical environment can have strong pressure dependence. The influence of these solute/solvent interactions on kinetic rates can have important implications in the context of the fuel-fouling problem. Supercritical methylcyclohexane pyrolysis was investigated in a specially constructed silica-lined flow reactor. Experiments in which the temperature and pressure were varied independently revealed a product distribution substantially different from numerous higher temperature gas-phase pyrolysis studies. Major products identified at 820 K and 45 atm included methane, ethane, propene, ethene, dimethylcyclopentane, propane, 1-methyl-1-cyclohexene, and ethylcyclopentane. As pressure was increased at 782 K, the selectivity of dimethylcyclopentane increased and was consistent with a mechanism that incorporated caging effects. Some observations related to polycyclic aromatic hydrocarbons (PAH) and solid formation were a natural extension of this research effort. PAH products observed included indene, methylnaphthalenes, dimethylnaphthalenes, fluorene, pyrene, methylanthracene, and benzo[ghi]perylene. A gas-phase model of methylcyclohexane pyrolysis was constructed and compared with experimental data from a sister effort in this laboratory. This model, along with two others currently being developed at Princeton, is the first elementary-reaction-based cycloalkane decomposition model ever created. Excellent agreement was found between the gas-phase model and experimental data for the major products observed. Preliminary steps were taken to extend this model to supercritical conditions through detailed consideration of the solute/solvent interactions present in the supercritical fluid and modifications made to the ideal gas model. Supercritical pyrolysis mechanisms of decalin and tetralin were also investigated. Major products of supercritical decalin pyrolysis included light alkanes and alkenes, methylhexahydroindane, indene, methylcyclohexenes, and indane. Major products of supercritical tetralin pyrolysis included: naphthalene, methylindane, ethane, methane, ethene, and phenylbutane. Quantification of the major products indicated that C6 to C5 ring contraction was found to occur preferentially with increasing pressure, consistent with the caging hypothesis.

  7. Catalytic partial oxidation of pyrolysis oils

    Science.gov (United States)

    Rennard, David Carl

    2009-12-01

    This thesis explores the catalytic partial oxidation (CPO) of pyrolysis oils to syngas and chemicals. First, an exploration of model compounds and their chemistries under CPO conditions is considered. Then CPO experiments of raw pyrolysis oils are detailed. Finally, plans for future development in this field are discussed. In Chapter 2, organic acids such as propionic acid and lactic acid are oxidized to syngas over Pt catalysts. Equilibrium production of syngas can be achieved over Rh-Ce catalysts; alternatively mechanistic evidence is derived using Pt catalysts in a fuel rich mixture. These experiments show that organic acids, present in pyrolysis oils up to 25%, can undergo CPO to syngas or for the production of chemicals. As the fossil fuels industry also provides organic chemicals such as monomers for plastics, the possibility of deriving such species from pyrolysis oils allows for a greater application of the CPO of biomass. However, chemical production is highly dependent on the originating molecular species. As bio oil comprises up to 400 chemicals, it is essential to understand how difficult it would be to develop a pure product stream. Chapter 3 continues the experimentation from Chapter 2, exploring the CPO of another organic functionality: the ester group. These experiments demonstrate that equilibrium syngas production is possible for esters as well as acids in autothermal operation with contact times as low as tau = 10 ms over Rh-based catalysts. Conversion for these experiments and those with organic acids is >98%, demonstrating the high reactivity of oxygenated compounds on noble metal catalysts. Under CPO conditions, esters decompose in a predictable manner: over Pt and with high fuel to oxygen, non-equilibrium products show a similarity to those from related acids. A mechanism is proposed in which ethyl esters thermally decompose to ethylene and an acid, which decarbonylates homogeneously, driven by heat produced at the catalyst surface. Chapter 4 details the catalytic partial oxidation of glycerol without preheat: droplets of glycerol are sprayed directly onto the top of the catalyst bed, where they react autothermally with contact times on the order of tau ? 30 ms. The reactive flash volatilization of glycerol results in equilibrium syngas production over Rh-Ce catalysts. In addition, water can be added to the liquid glycerol, resulting in true autothermal reforming. This highly efficient process can increase H2 yields and alter the H2 to CO ratio, allowing for flexibility in syngas quality depending on the purpose. Chapter 5 details the results of a time on stream experiment, in which optimal syngas conditions are chosen. Although conversion is 100% for 450 hours, these experiments demonstrate the deactivation of the catalyst over time. Deactivation is exhibited by decreases in H2 and CO 2 production accompanied by a steady increase in CO and temperature. These results are explained as a loss of water-gas shift equilibration. SEM images suggest catalyst sintering may play a role; EDS indicates the presence of impurities on the catalyst. In addition, the instability of quartz in the reactor is demonstrated by etching, resulting in a hole in the reactor tube at the end of the experiment. These results suggest prevaporization may be desirable in this application, and that quartz is not a suitable material for the reactive flash volatilization of oxygenated fuels. In Chapter 6, pyrolysis oil samples from three sources - poplar, pine, and hardwoods - are explored in the context of catalytic partial oxidation. Lessons derived from the tests with model compounds are applied to reactor design, resulting in the reactive flash vaporization of bio oils. Syngas is successfully produced, though deactivation due to coke and ash deposition keeps H2 below equlibrium. Coke formation is observed on the reactor walls, but is avoided between the fuel injection site and catalyst by increasing the proximity of these in the reactor design. Low temperatures are maintained in the fuel delivery system utilizing a water-

  8. Evaluation of pyrolysis curves for volatile elements in aqueous standards and carbon-containing matrices in electrothermal vaporization inductively coupled plasma mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Silva, A.F. [Delft University of Technology, Faculty of Applied Sciences, DelftChemTech, Julianalaan 136, 2628 BL Delft (Netherlands); Universidade Federal de Santa Catarina, Departamento de Quimica, 88040-900 Florianopolis, SC (Brazil); Welz, B. [Universidade Federal de Santa Catarina, Departamento de Quimica, 88040-900 Florianopolis, SC (Brazil); Loos-Vollebregt, M.T.C. de [Delft University of Technology, Faculty of Applied Sciences, DelftChemTech, Julianalaan 136, 2628 BL Delft (Netherlands)], E-mail: m.t.c.deloos-vollebregt@tudelft.nl

    2008-07-15

    Pyrolysis curves in electrothermal atomic absorption spectrometry (ET AAS) and electrothermal vaporization inductively coupled plasma mass spectrometry (ETV-ICP-MS) have been compared for As, Se and Pb in lobster hepatopancreas certified reference material using Pd/Mg as the modifier. The ET AAS pyrolysis curves confirm that the analytes are not lost from the graphite furnace up to a pyrolysis temperature of 800 deg. C. Nevertheless, a downward slope of the pyrolysis curve was observed for these elements in the biological material using ETV-ICP-MS. This could be related to a gain of sensitivity at low pyrolysis temperatures due to the matrix, which can act as carrier and/or promote changes in the plasma ionization equilibrium. Experiments with the addition of ascorbic acid to the aqueous standards confirmed that the higher intensities obtained in ETV-ICP-MS are related to the presence of organic compounds in the slurry. Pyrolysis curves for As, Se and Pb in coal and coal fly ash were also investigated using the same Pd/Mg modifier. Carbon intensities were measured in all samples using different pyrolysis temperatures. It was observed that pyrolysis curves for the three analytes in all slurry samples were similar to the corresponding graphs that show the carbon intensity for the same slurries for pyrolysis temperatures from 200 deg. C up to 1000 deg. C.

  9. An ill-posed parabolic evolution system for dispersive deoxygenation–reaeration in water

    International Nuclear Information System (INIS)

    We consider an inverse problem that arises in the management of water resources and pertains to the analysis of surface water pollution by organic matter. Most physically relevant models used by engineers derive from various additions and corrections to enhance the earlier deoxygenation–reaeration model proposed by Streeter and Phelps in 1925, the unknowns being the biochemical oxygen demand (BOD) and the dissolved oxygen (DO) concentrations. The one we deal with includes Taylor’s dispersion to account for the heterogeneity of the contamination in all space directions. The system we obtain is then composed of two reaction-dispersion equations. The particularity is that both Neumann and Dirichlet boundary conditions are available on the DO tracer while the BOD density is free of any conditions. In fact, for real-life concerns, measurements on the DO are easy to obtain and to save. On the contrary, collecting data on the BOD is a sensitive task and turns out to be a lengthy process. The global model pursues the reconstruction of the BOD density, and especially of its flux along the boundary. Not only is this problem plainly worth studying for its own interest but it could also be a mandatory step in other applications such as the identification of the location of pollution sources. The non-standard boundary conditions generate two difficulties in mathematical and computational grounds. They set up a severe coupling between both equations and they are the cause of the ill-posed data reconstruction problem. Existence and stability fail. Identifiability is therefore the only positive result one can search for; it is the central purpose of the paper. Finally, we have performed some computational experiments to assess the capability of the mixed finite element in missing data recovery. (paper)

  10. Moringa oleifera Lam. (Moringaceae) grown in Nigeria: In vitro antisickling activity on deoxygenated erythrocyte cells

    Science.gov (United States)

    Adejumo, Olufunmilayo E.; Kolapo, Adelodun L.; Folarin, Akintomiwa O.

    2012-01-01

    Context: Traditional medicine, which is more available and affordable for the poor uses medicinal plants for the treatment and management of various ailments, including the sickle cell disease (SCD). About 24 million Nigerians are carriers of this sickled cell gene, while approximately 2.4 million are SCD patients. Moringa oleifera Lam. (Moringaceae) possesses high nutritional value and has been used in folklore medicine to treat various ailments related to pain and inflammation. Chemical, pharmacological and pharmacognostical applications of Moringa oleifera have been reported. Objective: This study investigated the antisickling potential of polar and non-polar extracts of the seed, flower and leaf of Moringa oleifera for the first time. Materials and Methods: Using crude methanol extract, aqueous extract, ethyl acetate and butanol, the in vitro antisickling activities of Moringa oleifera fractions, were evaluated using erythrocyte cells deoxygenated with 2% sodium metabisulphite. p-Hydroxybenzoic acid and normal saline were employed as positive and negative controls. Results: Phytochemical screening revealed the presence of saponins, free anthraquinones, and alkaloids. Extracts of the seed and flower demonstrated a higher (P<0.05) antisickling activity in comparison to the leaf extract. The leaf extract, as well as those of the seed and flower, equally demonstrated a (P<0.05) reversal of sickled erythrocytes. Discussions and Conclusions: These findings suggest that Moringa oleifera may play a role in the management of SCD, by incorporation of its fractions into recipes. More extensive biological evaluations and further studies will be necessary for the chemical characterization of the antisickling principles. PMID:22557922

  11. Effect of combination of irradiation and zeolite on pyrolysis of polymer materials

    International Nuclear Information System (INIS)

    Fo0r recycling of waste polymers, degradation behavior of polypropylene (PP) and polyoxymethylene (POM) was studied by a combination of radiolysis and thermolysis methods. The results revealed that thermal degradation temperature of PP was significantly reduced when PP was irradiated in the presence of zeolite. Irradiation induced temperature reduction depended on zeolite structure and composition as well as on the morphology of the mixture. In the presence of zeolite, a series of oxidized products were formed. Initial temperature for the pyrolysis of POM was depressed by irradiation and the irradiated POM had lower final temperature of pyrolysis in the presence of zeolite

  12. Thermochemical behavior of tris(2-butoxyethyl) phosphate (TBEP) during co-pyrolysis with biomass.

    Science.gov (United States)

    Qian, Ting-Ting; Li, De-Chang; Jiang, Hong

    2014-09-16

    Co-pyrolysis of plastic waste and wood biomass to recover valuable chemicals is a cost-effective waste-recycling technology. However, widely used organophosphate ester additives in plastic, such as tris(2-butoxyethyl) phosphate (TBEP), can form diverse phosphorus (P)-containing species. These P-containing compounds can pose new environmental challenges when the biochar is reused. In this study, a mixture of TBEP and lignin was used to simulate the feedstock of plastic waste and wood biomass, and the thermochemical behavior of TBEP in slow pyrolysis (20 K min(-1)) and fast pyrolysis at 400-600 °C was investigated. The results show that low temperature in fast pyrolysis favors the enrichment of P in char. Up to 76.6% of initial P in the feedstock is retained in the char resulting from 400 °C, while only 51% is retained in the char from 600 °C. Slow pyrolysis favors the formation of stable P species regardless of the temperature; only 7% of the P retained in the char is extractable from char from slow pyrolysis, while 20-40% of P can be extracted from char resulting from fast pyrolysis. The addition of CaCl2 and MgCl2 can significantly increase the fraction of P retained in the char by the formation of Ca, Mg-P compounds. Online TG-FTIR-MS analysis suggests that TBEP undergoes decomposition through different temperature-dependent pathways. The P-containing radicals react with the aromatic rings produced by the pyrolysis of lignin to form Ar-P species, which is an important factor influencing the distribution and stabilization of P in char. PMID:25154038

  13. Co-pyrolysis and Catalytic Co-pyrolysis of Waste Tyres with Oil Palm Empty Fruit Bunches

    Directory of Open Access Journals (Sweden)

    K.N. Ismail

    2011-01-01

    Full Text Available Shredded Waste Tyres (SWT and Shredded Oil Palm Empty Fruit Bunches (SOPEFB were pyrolysed in a fixed bed reactor at 500C with a ratio of 1:1. SWT and impregnated SOPEFB with 10% w/w of cobalt catalyst solution were then pyrolysed in the same reactor at 500oC. The pyrolysed oils were collected in an ice/water condenser. The aim of this work is to study the effects of the addition of cobalt catalyst with direct impregnation into the SOPEFB fibers with respect to the liquid yields. The reactor was externally heated by means of electrical resistance, the heating rate being approximately 30C min-1. Once the required temperature obtained, it was maintained for 2 h. Three phases were obtained after pyrolysis : solid, liquid and gas. Highest yield of liquid product obtained with catalytic co-pyrolysis of SWT and SOPEFB as compared to co-pyrolysis of SWT and SOPEFB. It can be concluded that the catalytic co-pyrolysis using cobalt as catalyst resulted in higher of liquid yield.

  14. Study of mobilization and speciation of trace elements in coal pyrolysis

    International Nuclear Information System (INIS)

    Various types of coal contain high levels of a number of trace elements. Little is known of the fates of these trace elements during the conversion of coal to liquid and gaseous products. Studies were undertaken of mobilization and speciation of trace elements in coal pyrolysis, one of the major coal conversion processes. The bituminous coal was pyrolyzed to produce liquid and gaseous products. The pyrolysis products were collected in traps in an inert gas stream. In addition mildly hydrogenated coal was prepared by mixing with tetralin, a hydrogen donor solvent, at boiling temperature. In order to characterize each element specifically during pyrolysis, base samples of coal and mildly hydrogenated coal (H-coal) were spiked with heavy metal sulfides, trace metals bound to partially oxidized coal (coal humates), and halide salts prior to carrying out pyrolysis. Eight elements were investigated in this research. They are As, Br, Cl, Co, Cr, Mn, Se, and V. Pre-spiked hydrogenated coal, i.e., pulverized coal spiked with halide salts and heavy metal sulfides then hydrogenated with tetralin, was prepared and studied for the fates of these elements during pyrolysis. Chlorinated and brominated coals were also prepared to compare the volatility differences between organically and inorganically bound halogens during the pyrolysis reaction. These products and the coal char residues were analyzed for the spiked elements mainly by neutron activation analysis for the spiked elementactivation analysis for the spiked elements to determine their degree of volatility. Volatility and recovery (mass balance) will be discussed for those elements that appeared highly volatile during pyrolysis. In order to understand the halogenated compounds in the pyrolysis products, gas chromatograms were taken to the collected pyrolysis products of coal, hydrogenated coal, NaCl spiked coal, NaBr spiked coal, chlorinated coal, and brominated coal

  15. Modelling of pyrolysis of peat and biomass under combustion and gasification; Pyrolyysimalli turpeen ja biomassan poltolle ja kaasutukselle

    Energy Technology Data Exchange (ETDEWEB)

    Raiko, R.; Haukka, P.; Vehmaan-Kreula, M. [Tampere Univ. of Technology (Finland). Energy and Process Technology

    1997-10-01

    In the model developed during the research the chemical kinetics of pyrolysis is described with `the two competing reactions model`. Heat transfer in particle consists of convection and conduction. With the help of the model all the kinetic parameters of the two pyrolysis reactions are fitted with measured values. Also simple correlations for pyrolysis of peat under fluidized bed and pulverised flame conditions are given. The effect of the heating rate can be taken into account by using two competing Arrhenius-type reactions. In this model pyrolysis is modelled by using two reactions; one for the low temperature level and the other for the high temperature level. Both of these reactions consume the same unreacted fuel and this model is able to describe the pyrolysis at different temperature levels. Pyrolysis takes place in the heating stage of the particle before heterogeneous combustion and therefore temperature and density profiles inside the particle have to be solved simultaneously. The energy and mass balance equations of the particle form a set of partial differential equations (PDE), which is solved numerically by using so called method of lines, by converting PDE into a set of ordinary differential equations (ODE). The final solution of ODEs is received by using LSODE algorithm of Hindmash. An user friendly interface for the pyrolysis model is programmed by using Visual Basic enabling convenient variation of the conditions and observation of the results

  16. PYROLYSIS KINETICS OF WASHED PRECIPITATED LIGNIN

    Directory of Open Access Journals (Sweden)

    Christina Gustafsson

    2009-02-01

    Full Text Available This article describes the pyrolysis behavior of precipitated washed lignin in a Laminar Entrained Flow Reactor between 700 and 1000°C and at different residence times. Lignin was precipitated by acidification of softwood black liquor using CO2. After acid washing, the solid material was dried and sieved (80-100 ?m. This material was then fed into the reactor at a rate of about 0.1 g/min. The formed gases were analyzed with respect to CO, CO2, and CH4, and char was collected and weighed. A traditional first order Arrhenius kinetic expression, based on the temperature of the particles with respect to residence time, was adapted to the experimental results. The activation energy was found to be 32.1 kJ/mol. The low ash content in the washed lignin gave a very low solid material residue after the reactor.

  17. CO-PYROLYSIS OF POLYPROPYLENE WITH PETROLEUM OF BACIA DE CAMPOS

    Directory of Open Access Journals (Sweden)

    DE ASSUMPÇÃO, Luiz Carlos Fonte Nova; MARQUES, Mônica Regina da Costa; CARBONELL, Montserrat Motas

    2009-01-01

    Full Text Available In this study, the process of co-pyrolysis of polypropylene (PP residues with gas-oil was evaluated, varying thetemperature and the amount of polypropylene fed to the reactor. The polypropylene samples and gas-oil weresubmitted to the thermal co-pyrolysis in an inert atmosphere, varying the temperature and the amount of PP.The influence of the gas-oil was evaluated carrying the co-pyrolysis in the absence of PP. The pyrolysed liquidsproduced by this thermal treatment were characterized by modified gaseous chromatography in order toevaluate the yield in the range of distillation of diesel. As a result, the increase of PP amount lead to a reductionin the yield of the pyrolytic liquid and to an increase of the amount of solid generated. The effect of temperatureincrease showed an inverse result. The results show that plastic residue co-pyrolysys is a potential method forchemical recycling of plastic products.

  18. Fixed-bed hydrogen pyrolysis of rapeseed: product yields and compositions

    International Nuclear Information System (INIS)

    The fixed-bed hydro pyrolysis tests have been conducted on a sample of rapeseed to investigate the effect of hydro pyrolysis on the yields and chemical structures of bio-oils, with a view to improving overall product quality. A ammonium dioxydithiomolybdenate catalyst has been used in some tests to further increase conversion. The maximum bio-oil yield of 84% was obtained in hydrogen atmosphere (with catalyst) at hydrogen pressure of 15 MPa, hydrogen flow rate of 10 dm3min-1, hydro pyrolysis temperature of 520 degree C, and heating rate of 5 oCmin-1. Then this bio-oil was characterized by elemental analysis and some spectroscopic and chromatographic techniques. And finally, this bio-oil yield and chemical composition compared with oil obtained from fast pyrolysis condition

  19. Improved lignin pyrolysis for phenolics production in a bubbling bed reactor - Effect of bed materials.

    Science.gov (United States)

    Li, Dongbing; Briens, Cedric; Berruti, Franco

    2015-08-01

    Lignin pyrolysis was studied in a bubbling fluidized bed reactor equipped with a fractional condensation train, using nitrogen as the fluidization gas. The effect of different bed materials (silica sand, lignin char, activated lignin char, birch bark char, and foamed glass beads) on bio-oil yield and quality was investigated for a pyrolysis temperature of 550°C. Results how that a bed of activated lignin char is preferable to the commonly used silica sand: pyrolysis of Kraft lignin with a bed of activated lignin char not only provides a pure char product, but also a higher dry bio-oil yield (with a relative increase of 43%), lower pyrolytic water production, and better bio-oil quality. The bio-oil obtained from Kraft lignin pyrolysis with a bed of activated lignin char has a lower average molecular weight, less tar, more phenolics, and less acidity than when sand is used as bed material. PMID:25863324

  20. Fast pyrolysis of lignin, macroalgae and sewage sludge

    DEFF Research Database (Denmark)

    Trinh, Ngoc Trung

    2013-01-01

    In the last twenty years, the fast pyrolysis process has been explored to produce bio-oil from biomass. Fast pyrolysis is a thermal conversion technology that is performed at a temperatures of 450 - 600 ºC, high biomass heating ratess (100 - 2000 K/s), a short gas residence time (less than 2 s) with no presence of oxygen. Fast pyrolysis can convert a large fraction of the biomass to bio-oil, and smaller fractions of char and gas. The pyrolysis centrifuge reactor (PCR) has been developed at the CHEC center at DTU Department of Chemical Engineering. The reactor is a compact design that uses a low flow rate of carrier gas, pyrolyse biomass without a heat carrier and obtain a biomass particle heating rate of 1000 - 1500 K/s by a high centrifugal force. The reactor can be constructed at a size that could be applicable locally at waste water treatment plants or pulp and paper plants, bio-ethanol plants or can constructed as a mobile unit of a tractor-propelled vehicle that is used on straw fields. A lot of work on PCR straw and wood pyrolysis with respect to pyrolysis conditions, moisture feedstock content, bio-oil properties, and PCR modelling is done before this PhD project. The bio-oil yields of approximately 68 and 60 wt% daf are obtained for wood and straw PCR pyrolysis, respectively and the bio-oils properties are similar to those of wood and straw pyrolysis from fluidized-bed reactors. Wood and straw, conventional biomasses, are extensively investigated and knowledge of wood and straw fast pyrolysis is available in the literature. Nonconventional biomass feedstock may also be applicable for fast pyrolysis processes. Among the forms of nonconventional biomasses: macroalgae, lignin (industrial residue) and sewage sludge may be attractive materials due to their low price, non-competitiveness with food crops and the possible utilization of solid wastes. Besides, a fast pyrolysis process can be used as a process to densify the biomass and produce bioslurry, a mixture of bio-oil and pyrolytic char. The bioslurry is found to be a possible feedstock for pressurized gasification plants. Thus, the aims of this project are to investigate fast pyrolysis properties of lignin, sewage sludge and macroalgae on a lab scale PCR and characterize their bio-oil properties. Bioslurry properties with respect to use as a feedstock for pressurized gasification is also investigated. Lignin and sewage sludge PCR pyrolysis provided bio-oil yields of 47 and 54 wt% daf, and oil energy recovery of 45 and 50 %, respectively. While the macroalgae PCR pyrolysis showed promising results with an organic oil yield of 65 wt% daf and an oil energy recovery of 76 %. The lignin, macroalgae and sewage sludge bio-oil properties were relatively different to those of the straw or wood bio-oils with respect to oxygen content, viscosity, HHV and mean molecular mass. The HHV of the lignin, sewage sludge and macroalgae oils were 29.7, 25.7 and 25.5 MJ/kg db respectively, and that are higher than that of typical bioiv oil from conventional biomasses (23-24 MJ/kg db). Almost all metals feedstock contents were contained in the chars at temperatures of 550 - 575 °C for lignin, sewage sludge and macroalgae PCR pyrolysis. Therefore the bio-oils obtained low metal concentrations (especially alkali contents less than 0.09 wt%). Due to high feedstock nitrogen and sulfur contents, also a high level of nitrogen and sulfur of macroalgae and sewage sludge oils were observed compared to conventional bio-oil and this may limit their further industrial applications. The lignin char had a high proportion of small size particles, a HHV of 21 MJ/kg db and were almost free of chloride and sulfur, thus it is considered as a promising fuel for gasification or combustion; whereas macroalgae and sewage sludge chars containing high amounts of macronutrients as N, P, K, S, Mg and Ca and this could make the chars most valuable as raw materials for fertilizer production. The sewage sludge waste bulk volume (the char compared to the sludge) was reduced with 52 % by pyrolysis at 575 °C. It is s

  1. Advances in Modeling and Simulation of Biomass Pyrolysis

    Directory of Open Access Journals (Sweden)

    N. Prakash

    2009-01-01

    Full Text Available The various aspects of modeling and simulation work carried out so far in biomass pyrolysis since 1946 have been extensively reviewed in the present study. Biomass pyrolysis, one of the few non conventional energy routes, is highly promising and capable of handling the current energy crisis successfully for the present and in the near future. Pyrolysis as a stand alone or as the core of biomass gasification process is complex in nature, the understanding and knowledge of this multifaceted phenomenon can heavily influence the efficiency and effectiveness of the whole gasification process. Even though, the modeling of biomass pyrolysis process was initiated during 1940`s gradual changes, improvements and alternates have been carried out throughout these years. All these years, various modeling approaches were adopted, different kinetic schemes were proposed, diverse numerical schemes were followed and range of parameters were implemented, all these have developed a baffling picture over the subject. The complexity of the process, as such the large number of components involved in the intermediates and end products; the dependency of the process over numerous parameters namely the temperature, space and time dependent physical, thermodynamic and transport properties, the particle shape, size, shrinkage factors and moisture content all these justify even today the necessity and requirement of research for further improvement and enrichment in the modeling and simulation fronts of this process. This study sums up the work carried out in literature on modeling and simulation of wood pyrolysis and suggests new research directions and approaches necessarily to be made up in future.

  2. Fast pyrolysis of microalgae to produce renewable fuels

    Energy Technology Data Exchange (ETDEWEB)

    Miao, Xiaoling; Wu, Qingyu [Department of Biological Sciences and Biotechnology, Tsinghua University, Beijing 100084 (China); Yang, Changyan [Institute of Process Engineering, Chinese Academy of Science, Beijing 100080 (China)

    2004-06-01

    In the present study, fast pyrolysis tests of microalgae were performed in the fluid bed reactor. The experiments were completed at temperature of 500C with a heating rate of 600Cs{sup -1} and a sweep gas (N{sub 2}) flow rate of 0.4m{sup 3}h{sup -1} and a vapour residence time of 2-3s. In comparison with the previous studies on slow pyrolysis from microalgae in an autoclave, a greater amount of high quality bio-oil can be directly produced from continuously processing microalgae feeds at a rate of 4gmin{sup -1} in the present work, which has a potential for commercial application of large-scale production of liquid fuels. The liquid product yields of 18 and 24% from fast pyrolysis of Chllorella protothecoides and Microcystis aeruginosa were obtained. The saturated and polar fractions account for 1.14 and 31.17% of the bio-oils of microalgae on average, which are higher than those of bio-oil from wood. The H/C and O/C molar ratios of microalgae bio-oil are 1.7 and 0.3, respectively. The gas chromatograph analyses showed that the distribution of straight-chain alkanes of the saturated fractions from microalgae bio-oils were similar to diesel fuel. Bio-oil product from fast pyrolysis microalgae is characterized by low oxygen content with a higher heating value of 29MJ/kg, a density of 1.16kgl{sup -1} and a viscosity of 0.10Pas. These properties of bio-oil of microalgae make it more suitable for fuel oil use than fast pyrolysis oils from lignocellulosic materials.

  3. Kinetics of muscle deoxygenation and microvascular PO(2) during contractions in rat: comparison of optical spectroscopy and phosphorescence-quenching techniques.

    Science.gov (United States)

    Koga, Shunsaku; Kano, Yutaka; Barstow, Thomas J; Ferreira, Leonardo F; Ohmae, Etsuko; Sudo, Mizuki; Poole, David C

    2012-01-01

    The overarching presumption with near-infrared spectroscopy measurement of muscle deoxygenation is that the signal reflects predominantly the intramuscular microcirculatory compartment rather than intramyocyte myoglobin (Mb). To test this hypothesis, we compared the kinetics profile of muscle deoxygenation using visible light spectroscopy (suitable for the superficial fiber layers) with that for microvascular O(2) partial pressure (i.e., Pmv(O(2)), phosphorescence quenching) within the same muscle region (0.5?1 mm depth) during transitions from rest to electrically stimulated contractions in the gastrocnemius of male Wistar rats (n = 14). Both responses could be modeled by a time delay (TD), followed by a close-to-exponential change to the new steady level. However, the TD for the muscle deoxygenation profile was significantly longer compared with that for the phosphorescence-quenching Pmv(O(2)) [8.6 ± 1.4 and 2.7 ± 0.6 s (means ± SE) for the deoxygenation and Pmv(O(2)), respectively; P superficial muscle measured using visible light spectroscopy or Pmv(O(2)) and can be explained on the basis of known fiber-type differences in Pmv(O(2)) kinetics. These data suggest that, within the superficial and also deeper muscle regions, the ? of the deoxygenation signal may represent a useful index of local O(2) extraction kinetics during exercise transients. PMID:21979807

  4. Pyrolysis of polyolefins for increasing the yield of monomers’ recovery

    International Nuclear Information System (INIS)

    Highlights: ? Thermal and catalytic pyrolysis of mixed polyolefins in fluidized bed has been studied. ? We tested applicability of a commercial Ziegler–Natta catalyst (Z–N: TiCl4/MgCl2). ? The catalyst has a strong influence on product distribution, increasing gas fraction. ? At 650 °C the monomer generation increased by 55% when the catalyst was used. ? We showed the concept of treatment of mixed polyolefins without a need of separation. - Abstract: Pyrolysis of plastic waste is an alternative way of plastic recovery and could be a potential solution for the increasing stream of solid waste. The objective of this work was to increase the yield the gaseous olefins (monomers) as feedstock for polymerization process and to test the applicability of a commercial Ziegler–Natta (Z–N): TiCl4/MgCl2 for cracking a mixture of polyolefins consisted of 46% wt. of low density polyethylene (LDPE), 30% wt. of high density polyethylene (HDPE) and 24% wt. of polypropylene (PP). Two sets of experiments have been carried out at 500 and 650 °C via catalytic pyrolysis (1% of Z–N catalyst) and at 650 and 730 °C via only-thermal pyrolysis. These experiments have been conducted in a lab-scale, fluidized quartz-bed reactor of a capacity of 1–3 kg/h at Hamburg University. The results revealed a strong influence of temperature and presence of catalyst on the product distribution. The ratios of gas/liquid/solid mass fractions d mass fractions via thermal pyrolysis were: 36.9/48.4/15.7% wt. and 42.4/44.7/13.9% wt. at 650 and 730 °C while via catalytic pyrolysis were: 6.5/89.0/4.5% wt. and 54.3/41.9/3.8% wt. at 500 and 650 °C, respectively. At 650 °C the monomer generation increased by 55% up to 23.6% wt. of total pyrolysis products distribution while the catalyst was added. Obtained yields of olefins were compared with the naphtha steam cracking process and other potentially attractive processes for feedstock generation. The concept of closed cycle material flow for polyolefins has been discussed, showing the potential benefits of feedstock recycling in a plastic waste management.

  5. Construction of a Labview controlled pyrolysis unit for coupling to a Pyrola 85 pyrolysis chamber

    OpenAIRE

    Östman, Marcus; Näsström, Elin

    2012-01-01

    Pyrolysis is the process of molecular decomposition in an inert environment using heat. It is possible to fragment large molecules, such as polymers, by pyrolysis and separate the fragments directly in a GC. This makes it possible to form complex sample fingerprints that can be used in various applications, for example in forensic science. In this project, a malfunctioning Pyrola 85 pyrolysis unit was fixed by measuring the voltage signals from the photo diode during pyrolysis in a Labview pr...

  6. Fast microwave-assisted catalytic pyrolysis of sewage sludge for bio-oil production.

    Science.gov (United States)

    Xie, Qinglong; Peng, Peng; Liu, Shiyu; Min, Min; Cheng, Yanling; Wan, Yiqin; Li, Yun; Lin, Xiangyang; Liu, Yuhuan; Chen, Paul; Ruan, Roger

    2014-11-01

    In this study, fast microwave-assisted catalytic pyrolysis of sewage sludge was investigated for bio-oil production, with HZSM-5 as the catalyst. Pyrolysis temperature and catalyst to feed ratio were examined for their effects on bio-oil yield and composition. Experimental results showed that microwave is an effective heating method for sewage sludge pyrolysis. Temperature has great influence on the pyrolysis process. The maximum bio-oil yield and the lowest proportions of oxygen- and nitrogen-containing compounds in the bio-oil were obtained at 550°C. The oil yield decreased when catalyst was used, but the proportions of oxygen- and nitrogen-containing compounds were significantly reduced when the catalyst to feed ratio increased from 1:1 to 2:1. Essential mineral elements were concentrated in the bio-char after pyrolysis, which could be used as a soil amendment in place of fertilizer. Results of XRD analyses demonstrated that HZSM-5 catalyst exhibited good stability during the microwave-assisted pyrolysis of sewage sludge. PMID:25260179

  7. Catalytic pyrolysis of microalgae to high-quality liquid bio-fuels

    International Nuclear Information System (INIS)

    The pyrolytic conversion of chlorella algae to liquid fuel precursor in presence of a catalyst (Na2CO3) has been studied. Thermal decomposition studies of the algae samples were performed using TGA coupled with MS. Liquid oil samples were collected from pyrolysis experiments in a fixed-bed reactor and characterized for water content and heating value. The oil composition was analyzed by GC-MS. Pretreatment of chlorella with Na2CO3 influences the primary conversion of chlorella by shifting the decomposition temperature to a lower value. In the presence of Na2CO3, gas yield increased and liquid yield decreased when compared with non-catalytic pyrolysis at the same temperatures. However, pyrolysis oil from catalytic runs carries higher heating value and lower acidity. Lower content of acids in the bio-oil, higher aromatics, combined with higher heating value show promise for production of high-quality bio-oil from algae via catalytic pyrolysis, resulting in energy recovery in bio-oil of 40%. -- Highlights: ? The pyrolytic catalytic conversion of chlorella algae to liquid fuel precursor. ? Na2CO3 as a catalyst for the primary conversion of chlorella. ? Pyrolysis oil from catalytic runs carries higher heating value and lower acidity. ? High-quality bio-oil from algae via catalytic pyrolysis with energy recovery in bio-oil of 40%.

  8. Effects of heating rate on slow pyrolysis behavior, kinetic parameters and products properties of moso bamboo.

    Science.gov (United States)

    Chen, Dengyu; Zhou, Jianbin; Zhang, Qisheng

    2014-10-01

    Effects of heating rate on slow pyrolysis behaviors, kinetic parameters, and products properties of moso bamboo were investigated in this study. Pyrolysis experiments were performed up to 700 °C at heating rates of 5, 10, 20, and 30 °C/min using thermogravimetric analysis (TGA) and a lab-scale fixed bed pyrolysis reactor. The results show that the onset and offset temperatures of the main devolatilization stage of thermogravimetry/derivative thermogravimetry (TG/DTG) curves obviously shift toward the high-temperature range, and the activation energy values increase with increasing heating rate. The heating rate has different effects on the pyrolysis products properties, including biochar (element content, proximate analysis, specific surface area, heating value), bio-oil (water content, chemical composition), and non-condensable gas. The solid yields from the fixed bed pyrolysis reactor are noticeably different from those of TGA mainly because the thermal hysteresis of the sample in the fixed bed pyrolysis reactor is more thorough. PMID:25063973

  9. Characteristics and mechanism study of analytical fast pyrolysis of poplar wood

    International Nuclear Information System (INIS)

    Highlights: ? Analytical Py–GC/MS technique is employed for fast pyrolysis of poplar wood. ? The products include anhydrosugars, furans, phenols, linear carbonyls, etc. ? The formation characteristics of the individual pyrolytic products are revealed. ? We propose and discuss the possible pathways for the formation of major products. - Abstract: Analytical pyrolysis–gas chromatography/mass spectrometry (Py–GC/MS) was applied to achieve fast pyrolysis of poplar wood and on-line analysis of the pyrolysis vapors. Experiments were conducted to reveal the distribution of pyrolytic products under different pyrolysis temperatures (300–1000 °C) and times (5–30 s). During the fast pyrolysis process, the poplar wood started decomposition to form organic volatile products at the set temperature of 300 °C, and reached the maximum volatile product yield at around 550 °C. The products included various anhydrosugars, furans, phenolic compounds, linear carbonyls, linear acids, hydrocarbons, and so on. They exhibited different formation characteristics. Based on the experimental results, we discussed the possible pyrolytic pathways for the generation of the major products.

  10. Investigation on thermochemical behavior of co-pyrolysis between oil-palm solid wastes and paper sludge.

    Science.gov (United States)

    Lin, Yousheng; Ma, Xiaoqian; Yu, Zhaosheng; Cao, Yawen

    2014-08-01

    The pyrolysis characteristics of oil-palm solid wastes, paper sludge and their blends were studied via thermogravimetric analysis. Blends ranging from 10 wt.% to 90 wt.% on dosage ratio were prepared to investigate their co-pyrolysis behavior and kinetics. There was a synergistic interaction at low temperature during co-pyrolysis between oil-palm solid wastes and paper sludge. The synergistic interaction would improve thermochemical pyrolysis reactivity of the blends, which could be attributed to the hydrogenation role and the potential mineral catalytic effects on paper sludge pyrolysis. The value of average activation energy obtained by Starink and Friedmen methods did not gradually decline with the increasing proportion of oil-palm solid wastes in the blends. The lowest average activation energy was achieved when the percentage of oil-palm solid wastes was 70%, which was 152 kJ/mol by Starink and 149 kJ/mol by Friedmen, respectively. PMID:24935005

  11. Multisteps Global Kinetic Analysis of MSW Slow Pyrolysis

    Directory of Open Access Journals (Sweden)

    Dwi Aries Himawanto

    2013-12-01

    Full Text Available The goal of this research is to find relationships between single components slow pyrolysis characteristics and mixed component slow pyrolysis characteristics of segregated municipal solid wastes (MSW. The material of this research consists of organic wastes (bamboo wastes and banana leaves wastes and inorganic wastes (styrofoam wastes and snack wrapping wastes. The materials which used to study were the unprosessing waste. The samples were collected, dried and crushed until passing 20 mesh shieves then characterized in self manufactured macro balance. The thermogravimetry analyses were done to find the MSW slow pyrolysis characteristics. The 20 gram sample was placed in the furnace whose temperature is increased with 10 0C/min heating rate until reached 400 0 final temperature and held for 30 minutes before the sample is cooled into room temperature. One hundred ml/min nitrogen introduced from the bottom of furnace as a swept gas. The results of the research show that the global kinetic method could be used to predict the MSW single component activation energy but it should be modified to calculate the mixed sample activation energy . The predictive activation energy values which calculated based on weighed sum of single component have 18.5 % deviations if compared with experimental result.

  12. Synthesis of the methyl alpha-glycosides of some isomalto-oligosaccharides specifically deoxygenated at position C-3.

    Science.gov (United States)

    Petráková, E; Glaudemans, C P

    1996-04-30

    Methyl alpha-isomaltoside and methyl alpha-isomaltotrioside specifically deoxygenated at position C-3 of various glucopyranosyl units were synthesized by condensation of either 1,6-di-O-acetyl-2,4-di-O-benzyl-3-deoxy-alpha,beta-D-ribo-hexopyranos e (7) or 1,6-di-O-acetyl-2,3,4-tri-O-benzyl-alpha,beta-D-glucopyranose [mediated by silver perchlorate and tin(IV) chloride] with suitably blocked derivatives of methyl alpha-D-glucopyranoside, its 3-deoxy analog (6), or methyl 3'-deoxy alpha-isomaltoside (10), respectively. PMID:8653719

  13. Synthesis of the methyl alpha-glycosides of some isomalto-oligosaccharides specifically deoxygenated at position C-4.

    Science.gov (United States)

    Petráková, E; Glaudemans, C P

    1995-12-27

    Methyl alpha-isomaltoside and methyl alpha-isomaltotrioside specifically deoxygenated at position C-4 of various glucopyranosyl units were synthesized by condensation of either 1,6-di-O-acetyl-2,3-di-O-benzyl-4-deoxy-alpha,beta-D-xylo-hexopyranos e (7) or 1,6-di-O-acetyl-2,3,4-tri-O-benzyl-alpha,beta-D-glucopyranose (10) [mediated by silver perchlorate and tin(IV) chloride] with suitably blocked derivatives of methyl alpha-D-glucopyranoside, its 4-deoxy analog 6, or methyl 4'-deoxy alpha-isomaltoside (13), respectively. PMID:8593619

  14. Production and Characterization of Bio-Char from the Pyrolysis of Empty Fruit Bunches

    Directory of Open Access Journals (Sweden)

    Mohamad A. Sukiran

    2011-01-01

    Full Text Available Problem statement: The palm oil industry generates an abundance of oil palm biomass such as the Empty Fruit Bunch (EFB, shell, frond, trunk and Palm Oil Mill Effluent (POME. For 88 million tones of Fresh Fruit Bunch (FFB processed in 2008, the amount of oil palm biomass was more than 26 million tones. Studies about production of bio-char from oil palm biomass are still lacking in Malaysia. So, this study was aimed to: (i determine the effect of pyrolysis temperatures on bio-char yield (ii characterize the bio-char obtained under different pyrolysed temperatures. Approach: In this study, pyrolysis of EFB was conducted using a fluidized fixed bed reactor. The effect of pyrolysis temperatures on bio-char yield was investigated. The pyrolysis temperature used ranged from 300-700°C. The elemental analysis, calorific value, surface area and total pore volume of the bio-char were determined. Results: The highest bio char yield of 41.56% was obtained at an optimum pyrolysis temperature of 300°C with particle size of 91-106 μm and the heating rate of 30°C min-1. The calorific values of bio-char ranged from 23-26 MJ kg-1. Conclusion: It was found that the bio-char products can be characterized as carbon rich, high calorific value and potential solid biofuels.

  15. Catalytic Fast Pyrolysis: A Review

    Directory of Open Access Journals (Sweden)

    Theodore Dickerson

    2013-01-01

    Full Text Available Catalytic pyrolysis is a promising thermochemical conversion route for lignocellulosic biomass that produces chemicals and fuels compatible with current, petrochemical infrastructure. Catalytic modifications to pyrolysis bio-oils are geared towards the elimination and substitution of oxygen and oxygen-containing functionalities in addition to increasing the hydrogen to carbon ratio of the final products. Recent progress has focused on both hydrodeoxygenation and hydrogenation of bio-oil using a variety of metal catalysts and the production of aromatics from bio-oil using cracking zeolites. Research is currently focused on developing multi-functional catalysts used in situ that benefit from the advantages of both hydrodeoxygenation and zeolite cracking. Development of robust, highly selective catalysts will help achieve the goal of producing drop-in fuels and petrochemical commodities from wood and other lignocellulosic biomass streams. The current paper will examine these developments by means of a review of existing literature.

  16. A pyrolysis study for the thermal and kinetic characteristics of an agricultural waste with two different plastic wastes.

    Science.gov (United States)

    Çepelio?ullar, Özge; Pütün, Ay?e E

    2014-10-01

    In this study, thermochemical conversion of plastic wastes (PET and PVC) together with an agricultural waste (hazelnut shell) was investigated. In order to determine the thermal and kinetic behaviours, pyrolysis experiments were carried out from room temperature to 800 °C, with a heating rate of 10 °C min(-1) in the presence of a N2 atmosphere in a thermogravimetric analyzer. With the obtained thermogravimetric data, an appropriate temperature was specified for the pyrolysis of biomass-plastic wastes in a fixed-bed reactor. At the second step, pyrolysis experiments were carried out at the same conditions with the thermogravimetric analyzer, except the final temperature which was up to 500 °C in this case. After pyrolysis experiments, pyrolysis yields were calculated and characterization studies for bio-oil were investigated. Experimental results showed that co-pyrolysis has an important role in the determination of the pyrolysis mechanism and the process conditions while designing/implementing a thermochemical conversion method where biomass-plastic materials were preferred as raw materials. PMID:25062939

  17. Studies on Catalytic Pyrolysis of Mustard Press Cake with NaCl

    Directory of Open Access Journals (Sweden)

    Aparna Sarkar1

    2014-06-01

    Full Text Available Under this present investigation, non-catalytic and catalytic pyrolysis of mustard press cake (MPC was conducted in a 50 mm diameter and 640 mm long semi-batch pyrolyser in the temperature range of 673K to 1173K in a nitrogen atmosphere. Effects of temperature on yields of products, namely, char, pyro-oil and gas obtained from primary pyrolysis of MPC have been investigated. The kinetic rate constants of volatiles and char formations were determined in the temperature range under the study. The activation energies and pre-exponential factors were determined. The catalytic effects of NaCl on the pyrolysis of MPC have also been investigated at three different temperatures namely, 673K, 773K and 873K. Catalyst loading was varied from 5-15% (w/w biomass. The product yields of catalytic and non-catalytic pyrolysis of MPC was compared. The activation energies of catalytic pyrolysis have been observed to be low in comparison to non-catalytic ones.

  18. Syngas production by two-stage method of biomass catalytic pyrolysis and gasification.

    Science.gov (United States)

    Xie, Qinglong; Kong, Sifang; Liu, Yangsheng; Zeng, Hui

    2012-04-01

    A two-stage technology integrated with biomass catalytic pyrolysis and gasification processes was utilized to produce syngas (H(2)+CO). In the presence of different nickel based catalysts, effects of pyrolysis temperature and gasification temperature on gas production were investigated. Experimental results showed that more syngas and char of high quality could be obtained at a temperature of 750°C in the stage of pyrolysis, and in the stage of gasification, pyrolysis char (produced at 750°C) reacted with steam and the maximum yield of syngas was obtained at 850°C. Syngas yield in this study was greatly increased compared with previous studies, up to 3.29Nm(3)/kg biomass. The pyrolysis process could be well explained by Arrhenius kinetic first-order rate equation. XRD analyses suggested that formation of Mg(0.4)Ni(0.6)O and increase of Ni(0) crystallite size were two main reasons for the deactivation of nickel based catalysts at higher temperature. PMID:22342084

  19. Functional Near Infrared Spectroscopy (NIRS) signal improvement based on negative correlation between oxygenated and deoxygenated hemoglobin dynamics

    Science.gov (United States)

    Cui, Xu; Bray, Signe; Reiss, Allan L.

    2009-01-01

    Near infrared spectroscopy (NIRS) is a promising technology for functional brain imaging which measures hemodynamic signals from the cortex, similar to functional magnetic resonance imaging (fMRI), but does not require the participant to lie motionless in a confined space. NIRS can therefore be used for more naturalistic experiments, including face to face communication, or natural body movements, and is well suited for real-time applications that may require lengthy training. However, improving signal quality and reducing noise, especially noise induced by head motion, is challenging, particularly for real time applications. Here we study the properties of head motion induced noise, and find that motion noise causes the measured oxygenated and deoxygenated hemoglobin signals, which are typically strongly negatively correlated, to become more positively correlated. Next, we develop a method to reduce noise based on the principle that the concentration changes of oxygenated and deoxygenated hemoglobin should be negatively correlated. We show that despite its simplicity, this method is effective in reducing noise and improving signal quality, for both online and offline noise reduction. PMID:19945536

  20. Pyrolysis characteristics and kinetic analysis of different dewatered sludge.

    Science.gov (United States)

    Zhang, Qiang; Liu, Huan; Liu, Peng; Hu, Hongyun; Yao, Hong

    2014-10-01

    Pyrolysis behavior and kinetic properties of four different sludge, including raw sludge and three sludge respectively dewatered with FeCl3/CaO, FeCl3/CaO/coal and Fenton's reagent (Fe(2+)+H2O2)/CaO, were analyzed by using thermogravimetry coupled with Fourier transform infrared spectrometry (TG-FTIR). The results show that organics of raw sludge mainly decomposed at 378-676K, and the decomposition temperature of conditioned sludge was prolonged to 823K. Addition of coal and catalysis of CaO/ferric salt both promoted sludge pyrolysis, leading to more NH3, CH4 and CO productions. Compared with dry sludge, wet sludge pyrolysis was hard to finish completely, and the first peak of organics' decomposition appeared at higher temperature (about 573K). Additionally, the global reaction model was suited to determine kinetic parameters, which showed that dry sludge conditioned with more CaO addition had higher E values than those of dry raw sludge. Opposite results were obtained when sludge samples were wet. PMID:25151077

  1. Preparation of brightness stabilization agent for lignin containing pulp from biomass pyrolysis oils

    Science.gov (United States)

    Agblevor, Foster A. (Blacksburg, VA); Besler-Guran, Serpil (Flemington, NJ)

    2001-01-01

    A process for producing a brightness stabilization mixture of water-soluble organic compounds from biomass pyrolysis oils comprising: a) size-reducing biomass material and pyrolyzing the size-reduced biomass material in a fluidized bed reactor; b) separating a char/ash component while maintaining char-pot temperatures to avoid condensation of pyrolysis vapors; c) condensing pyrolysis gases and vapors, and recovering pyrolysis oils by mixing the oils with acetone to obtain an oil-acetone mixture; d) evaporating acetone and recovering pyrolysis oils; e) extracting the pyrolysis oils with water to obtain a water extract; f) slurrying the water extract with carbon while stirring, and filtering the slurry to obtain a colorless filtrate; g) cooling the solution and stabilizing the solution against thermally-induced gelling and solidification by extraction with ethyl acetate to form an aqueous phase lower layer and an organic phase upper layer; h) discarding the upper organic layer and extracting the aqueous layer with ethyl acetate, and discarding the ethyl acetate fraction to obtain a brown-colored solution not susceptible to gelling or solidification upon heating; i) heating the solution to distill off water and other light components and concentrating a bottoms fraction comprising hydroxyacetaldehyde and other non-volatile components having high boiling points; and j) decolorizing the stabilized brown solution with activated carbon to obtain a colorless solution.

  2. STEPWISE ISOTHERMAL FAST PYROLYSIS (SIFP OF BIOMASS PART I. SIFP OF PINE SAWDUST

    Directory of Open Access Journals (Sweden)

    Patricia López Rivilli

    2011-05-01

    Full Text Available Pyrolysis of pine wood sawdust was carried out using stepwise isothermal fast pyrolysis (SIFP, focusing on the search of reaction conditions to obtain chemicals in good yields from biomass. SIFP consists of successive isothermal fast pyrolysis reactions, where solid products obtained in the previous isothermal fast pyrolysis become the substrate of the subsequent reaction at a higher temperature. This article reports results obtained by SIFP of pine sawdust between 200 and 600°C using 100°C intervals under vacuum (0.2 mm, using nitrogen as carrier gas. Both sets of reactions made it possible to obtain most of the compounds that have been previously described in conventional fast pyrolysis experiments; however this system produces a smaller number of chemical compounds in each isothermal FP, making it easier to obtain determined chemicals with industrial or research value. Maximum yield of liquid products occurred at 300°C, giving around 30% of bio-oil, which contained mainly phenols and furan derivatives. Liquid-Liquid extraction led to a rich mixture of phenol derivatives. Results showed that SIFP is an interesting technique to obtain enriched fractions of products derived from biomass pyrolysis.

  3. Synthesis of nanosized Co3O4 particles by spray pyrolysis

    International Nuclear Information System (INIS)

    Nanosized Co3O4 particles were firstly prepared by spray pyrolysis without milling process. The as-prepared particles obtained by spray pyrolysis turned to nanosized Co3O4 particles with narrow size distribution and non-aggregation characteristics after post-treatment between post-treatment temperature of 500 and 800 deg. C. Ethylene glycol used as organic additive into spray solution enabled the formation of the nanosized Co3O4 particles in the spray pyrolysis. The mean size of the Co3O4 particles changed from several tens nanometer to micron size according to the post-treatment temperatures. The mean sizes of the particles measured from the scanning electron microscopy (SEM) photograph were 200 and 400 nm at post-treatment temperature of 700 and 800 deg. C

  4. FAST PYROLYSIS – EFFECT OF WOOD DRYING ON THE YIELD AND PROPERTIES OF BIO-OIL

    Directory of Open Access Journals (Sweden)

    Eriks Samulis

    2007-11-01

    Full Text Available The composition and properties of the products of fast pyrolysis of hardwood, obtained in a two-chamber (drying and pyrolytic ablation type reactor in the temperature range 450-600º?, were investigated. It has been found that, upon the additional drying of wood at 200º? and subsequent pyrolysis, the quality of bio-oil is improved owing to the decrease in the amount of water and acids. It has been shown that the increase of the drying temperature to 240º? decreases the yield of the main product. Optimum parameters of the drying conditions and the temperature of the pyrolysis of wood, at which the bio-oil yield exceeds 60% and its calorific value makes up 17-20 ?J/kg, have been determined.

  5. Liquid-phase processing of fast pyrolysis bio-oil using platinum/HZSM-5 catalyst

    Science.gov (United States)

    Santos, Bjorn Sanchez

    Recent developments in converting biomass to bio-chemicals and liquid fuels provide a promising sight to an emerging biofuels industry. Biomass can be converted to energy via thermochemical and biochemical pathways. Thermal degradation processes include liquefaction, gasification, and pyrolysis. Among these biomass technologies, pyrolysis (i.e. a thermochemical conversion process of any organic material in the absence of oxygen) has gained more attention because of its simplicity in design, construction and operation. This research study focuses on comparative assessment of two types of pyrolysis processes and catalytic upgrading of bio-oil for production of transportation fuel intermediates. Slow and fast pyrolysis processes were compared for their respective product yields and properties. Slow pyrolysis bio-oil displayed fossil fuel-like properties, although low yields limit the process making it uneconomically feasible. Fast pyrolysis, on the other hand, show high yields but produces relatively less quality bio-oil. Catalytic transformation of the high-boiling fraction (HBF) of the crude bio-oil from fast pyrolysis was therefore evaluated by performing liquid-phase reactions at moderate temperatures using Pt/HZSM-5 catalyst. High yields of upgraded bio-oils along with improved heating values and reduced oxygen contents were obtained at a reaction temperature of 200°C and ethanol/HBF ratio of 3:1. Better quality, however, was observed at 240 °C even though reaction temperature has no significant effect on coke deposition. The addition of ethanol in the feed has greatly attenuated coke deposition in the catalyst. Major reactions observed are esterification, catalytic cracking, and reforming. Overall mass and energy balances in the conversion of energy sorghum biomass to produce a liquid fuel intermediate obtained sixteen percent (16 wt.%) of the biomass ending up as liquid fuel intermediate, while containing 26% of its initial energy.

  6. SPHERICAL CALCIA STABILIZED ZIRCONIA POWDERS OBTAINED BY SPRAY PYROLYSIS

    Scientific Electronic Library Online (English)

    H. E, Esparza-Ponce; A, Reyes-Rojas; M, Miki Yoshida.

    2001-12-01

    Full Text Available Las propiedades físicas y químicas de los polvos cerámicos dependen grandemente de la morfología y de la composición química de las soluciones precursoras. Por lo tanto, las propiedades de los polvos cerámicos están esperando ser mejoradas controlando los parámetros que más influyen en la morfología [...] como son la composición de las soluciones precursoras, temperatura y flujo de aire. Algunas de las técnicas que ofrecen producir polvos cerámicos con morfología controlada son: sol gel, coprecipitación y pirólisis. Dentro de estas técnicas la aspersión pirolítica es una de las más adecuadas para el control de la morfología y la composición química de las partículas, ya que la aspersión pirolítica integra la evaporación, precipitación, descomposición y estado de sinterización para la síntesis de polvos en un sólo proceso continuo. En este trabajo, los polvos obtenidos son esféricos y han sido preparados a partir de acetilacetonato de circonio y acetato de calcio en solución; mediante la técnica de aspersión pirolítica utilizando un aspersor neumático. La morfología y el tamaño de partícula cambian con las variaciones del flujo de aire, temperatura y la concentración molar de la solución. Abstract in english Physical and chemical properties of ceramic powders are highly dependent on the morphology and chemical composition of the precursor powders. Therefore, properties of ceramic powders are expecting to be improved by controlling the most important parameters of morphology such as composition of precur [...] sors, temperature and airflow. Promising techniques to produce ceramic powders with controlled morphology are sol-gel, coprecipitation, and pyrolysis. Among these techniques, spray pyrolysis is one of the most suitable to control the morphology and the chemical composition of the particles, because the spray pyrolysis technique integrates the evaporation, precipitation, decomposition and sintering stage of powder synthesis into a single continuos process. Spherical powders were prepared from acetylacetonate of zirconium and acetate calcium hydrated solutions by pneumatic spray pyrolysis. The morphology and size of the powders change with variation of airflow, temperature, and solution concentration.

  7. SPHERICAL CALCIA STABILIZED ZIRCONIA POWDERS OBTAINED BY SPRAY PYROLYSIS

    Directory of Open Access Journals (Sweden)

    H. E Esparza-Ponce

    2001-12-01

    Full Text Available Physical and chemical properties of ceramic powders are highly dependent on the morphology and chemical composition of the precursor powders. Therefore, properties of ceramic powders are expecting to be improved by controlling the most important parameters of morphology such as composition of precursors, temperature and airflow. Promising techniques to produce ceramic powders with controlled morphology are sol-gel, coprecipitation, and pyrolysis. Among these techniques, spray pyrolysis is one of the most suitable to control the morphology and the chemical composition of the particles, because the spray pyrolysis technique integrates the evaporation, precipitation, decomposition and sintering stage of powder synthesis into a single continuos process. Spherical powders were prepared from acetylacetonate of zirconium and acetate calcium hydrated solutions by pneumatic spray pyrolysis. The morphology and size of the powders change with variation of airflow, temperature, and solution concentration.Las propiedades físicas y químicas de los polvos cerámicos dependen grandemente de la morfología y de la composición química de las soluciones precursoras. Por lo tanto, las propiedades de los polvos cerámicos están esperando ser mejoradas controlando los parámetros que más influyen en la morfología como son la composición de las soluciones precursoras, temperatura y flujo de aire. Algunas de las técnicas que ofrecen producir polvos cerámicos con morfología controlada son: sol gel, coprecipitación y pirólisis. Dentro de estas técnicas la aspersión pirolítica es una de las más adecuadas para el control de la morfología y la composición química de las partículas, ya que la aspersión pirolítica integra la evaporación, precipitación, descomposición y estado de sinterización para la síntesis de polvos en un sólo proceso continuo. En este trabajo, los polvos obtenidos son esféricos y han sido preparados a partir de acetilacetonato de circonio y acetato de calcio en solución; mediante la técnica de aspersión pirolítica utilizando un aspersor neumático. La morfología y el tamaño de partícula cambian con las variaciones del flujo de aire, temperatura y la concentración molar de la solución.

  8. Pyrolysis of humic and fulvic acids

    Science.gov (United States)

    Wershaw, R.L.; Bohner, G.E., Jr.

    1969-01-01

    Pyrolysis of humic and fulvic acids isolated from a North Carolina soil yields a variety of aromatic, heterocyclic and straight chain organ compounds. The pyrolysis products identified by gas chromatography and mass spectrometry indicate that humic and fulvic acids have aromatic and polysaccharide structures in their molecules. ?? 1969.

  9. Toxicity of pyrolysis gases from polyoxymethylene

    Science.gov (United States)

    Hilado, C. J.; Schneider, J. E.; Brauer, D. P.

    1979-01-01

    A sample of polyoxymethylene was evaluated for toxicity of pyrolysis gases, using the toxicity screening test method developed at the University of San Francisco. Under several test conditions, this material gave shorter times to death than many other synthetic polymers. Carbon monoxide appeared to be the principal toxicant in the pyrolysis gases.

  10. Application of pyrolysis process to remove and recover liquid crystal and films from waste liquid crystal display glass

    International Nuclear Information System (INIS)

    Highlights: ? Pyrolysis process can recycle the liquid crystal and films from liquid crystal display glass successfully. ? The removal of organic parts from the liquid crystal glass reached 87.87 wt%. ? The mechanism analysis of pyrolysis process explains the whole pyrolysis process perfect. ? All pyrolysis products can be tilized by a reasonable way. - Abstract: Liquid crystal display (LCD) glass mainly consists of polarizing film, liquid crystal and glass substrate. Removing and recovering the liquid crystal and films from the LCD glass effectively has important significance for recovering the other parts. This study proposed a pyrolysis process to recover the organic parts from LCD glass. Through thermal gravimetric analysis, the pyrolysis temperature of the LCD glass could be chosen at 850 K. The removal rate of organic parts from LCD glass reached 87.87 wt%. Pyrolysis products consisted of 66.82 wt% oils, 21.01 wt% gaseous and 12.13 wt% residues. In addition, the oils contained 46.27 wt% acetic acid and 32.94 wt% triphenyl phosphate. Then, the pyrolysis mechanisms and products sources of the liquid crystal glass have been analyzed based on the information of bonds energy. The pyrolysis mechanism analysis proved that the products mainly consisted of acetic acid, triphenyl phosphate and C, which is consistent to the results of GC–MS analysis. A reasonable way has been put forward to recycle the pyrolysis products: acetic acid and triphenyl phosphate can bid and triphenyl phosphate can be collected by distillation, the rest oils and gases can be used as fuel and the remained glass can be used to extract indium and to produce building materials.

  11. Flash pyrolysis of sunflower oil cake for production of liquid fuels

    Energy Technology Data Exchange (ETDEWEB)

    Yorgun, S.; Sensoez, S. [Department of Chemical Engineering, Faculty of Engineering, Osmangazi University, 26480 Eskisehir (Turkey); Kockar, O.M. [Department of Chemical Engineering, Faculty of Engineering, Anadolu University, 26470 Eskisehir (Turkey)

    2001-06-01

    Flash pyrolysis experiments of sunflower (Helianthus annuus L.) press oil cake were performed in a tubular transport reactor at atmospheric pressure under nitrogen atmosphere. The effects of pyrolysis temperature, particle size and sweep gas flow rate on the yields of products were investigated. The temperature of pyrolysis, particle size and sweep gas flow rate were varied in the ranges 450-700C, D{sub p}<0.224, 0.224-0.425, 0.425-0.850 mm and 25-600 cm{sup 3} min{sup -1}, respectively. The maximum oil yield of ca. 45% was obtained at a pyrolysis temperature of 550C, with the sweep gas flow rate of 300 cm{sup 3} min{sup -1} and particle size of 0.425-0.850 mm. The elemental analysis and calorific value of the pyrolysis oil were determined, and then the chemical composition of the oil was investigated using chromatographic and spectroscopic techniques (1H NMR, IR, column chromatography and GC). The chemical characterization has shown that the oil obtained from sunflower oil cake can be used as a renewable fuel and chemical feedstock.

  12. High-speed pyrolysis with circulating heat carriers; Schnell-Pyrolyse mit zirkulierenden Waermetraegern

    Energy Technology Data Exchange (ETDEWEB)

    Schmalfeld, J.; Albrecht, J.; Solmaz, S.; Zentner, U. [Lurgi Energie und Umwelt GmbH, Frankfurt am Main (Germany)

    1998-09-01

    Yields and product compositions of pyrolysis reactions depend on the mode of heat supply, the temperature level, and the time of residue at reaction temperature. Using hot circulating granular materials mixed with solid or liquid materials (e.g. biogenic or hydrocarbon-rich residues and waste materials or refinery residues), the following important processes can be investigated: Separation of pyrolysis reaction and heat supply - accurate, optimal temperature levels for pyrolysis, e.g. between 5000 and 850 degrees centigrade - undiluted, unmixed pyrolysis gas - short times of residue of the pyrolysis gas for suppression of secondary reactions. (orig.) [Deutsch] Ausbeuten und Produktzusammensetzung von Pyrolyse-Reaktionen werden weitestgehend durch die Art und Weise der Waermezufuhr, das Temperaturniveau und die Verweilzeit bei Reaktionstemperatur bestimmt. Mit Hilfe des Prinzips heisser, umlaufender, koerniger Waermetraeger in Vermischung - fuer die Pyrolyse-Reaktion - mit festen oder fluessigen Einsatzstoffen (z.B. biogene oder kohlenwasserstoffreiche Rest-/Abfallstoffe, Raffinerie-Rueckstaende) lassen sich folgende wichtige, haeufig gewuenschte Vorgaenge realisieren: - Trennung von Pyrolyse-Reaktion und Waermeversorgung - Temperaturgenaue Pyrolyse-Reaktion auf gewuenschtem, optimalem Niveau waehlbar zwischen z.B. 5000 C und 850 C - Erhalt eines unverduennten, unvermischten Pyrolysegases - Kurze Verweilzeiten des Pyrolysegases zur Unterdrueckung von Sekundaerreaktionen. (orig.)

  13. Photoluminescence of spray pyrolysis deposited ZnO nanorods

    OpenAIRE

    Mikli Valdek; Kärber Erki; Raadik Taavi; Dedova Tatjana; Krustok Jüri; Mere Arvo; Krunks Malle

    2011-01-01

    Abstract Photoluminescence of highly structured ZnO layers comprising well-shaped hexagonal rods is presented. The ZnO rods (length 500-1,000 nm, diameter 100-300 nm) were grown in air onto a preheated soda-lime glass (SGL) or ITO/SGL substrate by low-cost chemical spray pyrolysis method using zinc chloride precursor solutions and growth temperatures in the range of 450-550°C. We report the effect of the variation in deposition parameters (substrate type, growth temperature, spray rate, ...

  14. Recycling of polymers by pyrolysis

    OpenAIRE

    Kaminsky, W

    1993-01-01

    The pyrolysis of plastic waste, scrap tires and other polymeric materials in a fluidized bed has been carried out based on a scale up program (laboratory plants 70 g/h, 500 g/h, 3000 g/h, and pilot plant 20-50 kg/h). The fluidized bed shows short residence times and high heat and mass transfers, and is heated indirectly up to 600 - 800°C. In the case of poly(methylmethacrylate) (PMMA) or polystyrene as feedstock up to 97 wt.% of the monomer can be recovered. Other polymers give a more unspeci...

  15. Kinetics of coal pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Seery, D.J.; Freihaut, J.D.; Proscia, W.M. (United Technologies Research Center, East Hartford, CT (USA)); Howard, J.B.; Peters, W.; Hsu, J.; Hajaligol, M.; Sarofim, A. (Massachusetts Inst. of Tech., Cambridge, MA (USA)); Jenkins, R.; Mallin, J.; Espindola-Merin, B. (Pennsylvania State Univ., University Park, PA (USA)); Essenhigh, R.; Misra, M.K. (Ohio State Univ., Columbus, OH (USA))

    1989-07-01

    This report contains results of a coordinated, multi-laboratory investigation of coal devolatilization. Data is reported pertaining to the devolatilization for bituminous coals over three orders of magnitude in apparent heating rate (100 to 100,000 + {degree}C/sec), over two orders of magnitude in particle size (20 to 700 microns), final particle temperatures from 400 to 1600{degree}C, heat transfer modes ranging from convection to radiative, ambient pressure ranging from near vacuum to one atmosphere pressure. The heat transfer characteristics of the reactors are reported in detail. It is assumed the experimental results are to form the basis of a devolatilization data base. Empirical rate expressions are developed for each phase of devolatilization which, when coupled to an awareness of the heat transfer rate potential of a particular devolatilization reactor, indicate the kinetics emphasized by a particular system reactor plus coal sample. The analysis indicates the particular phase of devolatilization that will be emphasized by a particular reactor type and, thereby, the kinetic expressions appropriate to that devolatilization system. Engineering rate expressions are developed from the empirical rate expressions in the context of a fundamental understanding of coal devolatilization developed in the course of the investigation. 164 refs., 223 figs., 44 tabs.

  16. FAST PYROLYSIS – EFFECT OF WOOD DRYING ON THE YIELD AND PROPERTIES OF BIO-OIL

    OpenAIRE

    Eriks Samulis; Valdis Kampars; Aleksandr Volpert; Igors Urbanovich; Galina Dobele

    2007-01-01

    The composition and properties of the products of fast pyrolysis of hardwood, obtained in a two-chamber (drying and pyrolytic) ablation type reactor in the temperature range 450-600º?, were investigated. It has been found that, upon the additional drying of wood at 200º? and subsequent pyrolysis, the quality of bio-oil is improved owing to the decrease in the amount of water and acids. It has been shown that the increase of the drying temperature to 240º? decreases the yield of the main produ...

  17. Analytical pyrolysis of humic substances: pitfalls, limitations, and possible solutions

    OpenAIRE

    Sáiz-Jiménez, Cesáreo

    1994-01-01

    Analytical pyrolysis is a technique currently used for investigating structural features of complex macromolecular materials. However, pitfalls appear to be widespread in pyrolysis studies ofhumic substances, and serious limitations can be experienced during the analytical procedure due to thermal reactions and configuration of the pyrolysis units and chromatographic systems. Pyrolysis presents inconsistencies for chemical studies, and the interpretation of the chemica...

  18. Co-pyrolysis characteristics and kinetics of coal and plastic blends

    International Nuclear Information System (INIS)

    Co-pyrolysis behaviors of different plastics (high density polyethylene, low density polyethylene and polypropylene), low volatile coal (LVC) and their mixtures were investigated by TGA. Experiments were conducted under N2 atmosphere at heating rate of 20 deg. C/min from room temperature to 750 deg. C. The results showed that the thermal degradation temperature range of plastic was 438-521 deg. C, while that of coal (LVC) was 174-710 deg. C. Plastics showed similar pyrolysis characteristics due to similar chemical bonds in their molecular structures. The overlapping degradation temperature interval between coal and plastic provide an opportunity for free radicals from coal pyrolysis to participate in the reactions of plastic decomposition. The difference of weight loss percent (?W) between experimental and theoretical ones, calculated as an algebraic sum of those from each separated component, ?W is 2.0-2.7% at the pyrolysis temperature higher than 530 deg. C, which indicates that the synergistic effect during pyrolysis occurs mainly in the high temperature region. The kinetic studies were performed according to Coats and Redfern method for first-order reaction. It was found that for plastics (HDPE, LDPE and PP), the pyrolysis process can be described by one first-order reaction. However, for LVC and LVC/plastic blends, this process can be described by three and four consecutive first-order reactions, respectively. The estimated kinetic parameters viz., aThe estimated kinetic parameters viz., activation energies and pre-exponential factors for coal, plastic and their blends, were found to be in the range of 35.7-572.8 kJ/mol and 27-1.7 x 1038 min-1, respectively

  19. Deoxygenation and the blood volume signals in the flexor carpi ulnaris and radialis muscles obtained during the execution of the Mirallas's test of judo athletes

    Science.gov (United States)

    Verdaguer-Codina, Joan; Mirallas, Jaume A.

    1996-12-01

    The technique of execution of any movement in Judo is extremely important. The coaches want tests and tools easy to use and cheaper, to evaluate the progress of a judoist in the tatame. In this paper we present a test developed by Mirallas, which has his name 'Test of Mirallas' to evaluate the maximal power capacity of the judoist. The near infrared spectroscopy (NIRS) signals were obtained to have a measurement of the metabolic work of the flexor carpi ulnaris and radialis muscles, during the execution of the ippon-seoi-nage movement, allowing this measurement to assess by NIRS the maximal oxygen uptake. Also obtained were tympanic, skin forehead, and biceps brachii temperatures during the test time and recovery phase to study the effects of ambient conditions and the post-exercise oxygen consumption. The deoxygenation and blood volume signals obtained gave different results, demonstrating the hypothesis of the coaches that some judoist do the execution of the ippon-seoi-nage movement correctly and the rest didn't. The heart rate frequency obtained in the group of judoist was between 190-207 bpm, and in the minute five of post-exercise was 114-137 bpm; the time employed in the MIrallas's test were from 7 feet 14 inches to 13 feet 49 inches, and the total of movements were from 199 to 409. The data obtained in the skin forehead, and skin biceps brachii confirms previous works that the oxygen consumption remains after exercise in the muscle studied. According to the results, the test developed by Mirallas is a good tool to evaluate the performance of judoist any time, giving better results compared with standard tests.

  20. Scaling heat and mass flow through porous media during pyrolysis

    Science.gov (United States)

    Maes, Julien; Muggeridge, Ann H.; Jackson, Matthew D.; Quintard, Michel; Lapene, Alexandre

    2015-03-01

    The modelling of heat and mass flow through porous media in the presence of pyrolysis is complex because various physical and chemical phenomena need to be represented. In addition to the transport of heat by conduction and convection, and the change of properties with varying pressure and temperature, these processes involve transport of mass by convection, evaporation, condensation and pyrolysis chemical reactions. Examples of such processes include pyrolysis of wood, thermal decomposition of polymer composite and in situ upgrading of heavy oil and oil shale. The behaviours of these systems are difficult to predict as relatively small changes in the material composition can significantly change the thermophysical properties. Scaling reduces the number of parameters in the problem statement and quantifies the relative importance of the various dimensional parameters such as permeability, thermal conduction and reaction constants. This paper uses inspectional analysis to determine the minimum number of dimensionless scaling groups that describe the decomposition of a solid porous material into a gas in one dimension. Experimental design is then used to rank these scaling groups in terms of their importance in describing the outcome of two example processes: the thermal decomposition of heat shields formed from polymer composites and the in situ upgrading of heavy oils and oil shales. A sensitivity analysis is used to divide these groups into three sets (primary, secondary and insignificant), thus identifying the combinations of solid and fluid properties that have the most impact on the performance of the different processes.

  1. Pore Scale Analysis of Oil Shale/Sands Pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Chen-Luh; Miller, Jan

    2011-03-01

    There are important questions concerning the quality and volume of pore space that is created when oil shale is pyrolyzed for the purpose of producing shale oil. In this report, 1.9 cm diameter cores of Mahogany oil shale were pyrolyzed at different temperatures and heating rates. Detailed 3D imaging of core samples was done using multiscale X-ray computed tomography (CT) before and after pyrolysis to establish the pore structure. The pore structure of the unreacted material was not clear. Selected images of a core pyrolyzed at 400oC were obtained at voxel resolutions from 39 microns (?m) to 60 nanometers (nm). Some of the pore space created during pyrolysis was clearly visible at these resolutions and it was possible to distinguish between the reaction products and the host shale rock. The pore structure deduced from the images was used in Lattice Boltzmann simulations to calculate the permeability in the pore space. The permeabilities of the pyrolyzed samples of the silicate-rich zone were on the order of millidarcies, while the permeabilities of the kerogen-rich zone after pyrolysis were very anisotropic and about four orders of magnitude higher.

  2. Pyrolysis of petroleum fractions on an indium oxide catalyst

    International Nuclear Information System (INIS)

    Results are presented for the pyrolysis of individual hydrocarbons (hexane and cyclohexane), a mixture of n-paraffins boiling in the 100 to 3000 range, and straight-run gasoline fractions with indium oxide as a catalyst. It was found that optimum dilution of the petroleum fraction with steam occurred at a molar ratio of 1:1. The presence of the indium catalyst was found to increase the yield of low molecular weight olefins under the selected experimental conditions by about 20% when compared with the pyrolysis without an active component catalyst. Kinetic studies of the catalytic reaction indicated that under conditions of pyrolysis, indium oxide takes part in a redox type reaction; also, oxidation which requires the higher temperature is the limiting stage of redox conversions. X-ray studies confirmed the possibility of redox transformation of indium oxide under pyrolytic conditions and the consequent variations in catalytic behavior. Further, an isotope tracer method was used to study the reaction mechanism in the interaction of RH type hydrocarbons and water

  3. Investigation of a process for the pyrolysis of plutonium contaminated combustible solid waste

    International Nuclear Information System (INIS)

    Pyrolysis offers an attractive first-stage alternative to incineration as a means of weight and volume reduction of solide combustible waste P.C.M, if it is required to recover plutonium from the final product. The avoidance of turbulent conditions associated with incineration should lead to less carry-over of particulates, and the lower operating temperature approximately 7000C should be most advantageous to the choice of constructional materials and to plant life. The char product from pyrolysis may be oxidised to a final ash at similarly acceptable low temperatures by passing air over a stirred bed of materials. The recently received draft designs for a cyclone after-burner (plus associated scrubbers and filters etc) offer an attractive method of dispensing of the volatile products of pyrolysis

  4. Hydrous pyrolysis of crude oil in gold-plated reactors

    Science.gov (United States)

    Curiale, J.A.; Lundegard, P.D.; Kharaka, Y.K.

    1992-01-01

    Crude oils from Iraq and California have been pyrolyzed under hydrous conditions at 200 and 300??C for time periods up to 210 days, in gold-plated reactors. Elemental (vanadium, nickel), stable isotopic (carbon), and molecular (n-alkanes, acyclic isoprenoids, steranes, terpanes and aromatic steroid hydrocarbons) analyses were made on the original and pyrolyzed oils. Various conventional crude oil maturity parameters, including 20S/(20S + 20R)-24-ethylcholestane ratios and the side-chain-length distribution of aliphatic and aromatic steroidal hydrocarbons, were measured in an effort to assess the modification of molecular maturity parameters in clay-free settings, similar to those encountered in "clean" reservoirs. Concentrations of vanadium and nickel in the Iraq oil decrease significantly and the V/(V + Ni) ratio decreases slightly, with increasing pyrolysis time/temperature. Whole oil carbon isotope ratios remain fairly constant during pyrolysis, as do hopane/sterane ratios and carbon number distribution of 5??(H),14??(H),17??(H),20R steranes. These latter three parameters are considered maturity-invariant. The ratios of short side-chain components to long side-chain components of the regular steranes [C21/(C21 + C29R)] and the triaromatic steroid hydrocarbons [C21/(C21 + C28)] vary systematically with increasing pyrolysis time, indicating that these parameters may be useful as molecular maturity parameters for crude oils in clay-free reservoir rocks. In addition, decreases in bisnorhopane/hopane ratio with increasing pyrolysis time, in a clay-free and kerogen-free environment, suggest that the distribution of these compounds is controlled by either differential thermal stabilities or preferential release from a higher-molecular weight portion of the oil. ?? 1992.

  5. Pyrolysis study of 2,4-dibromophenol reflecting reactions with PP in a post-treatment decontamination process

    OpenAIRE

    LUDA DI CORTEMIGLIA, Maria Paola

    2005-01-01

    Halogen-containing aromatics, mainly bromine-containing phenols are harmful compounds contaminating pyrolysis oil from electronic boards containing halogenated flame retardants. In addition, their formation increases the potential for evolution of polybrominated dibenzo-p-dioxins (PBDDs) and dibenzofurans (PBDFs) at relatively low temperature (up to 500 °C). As a model compound, 2,4-dibromophenol (DBP), was pyrolyzed at 290 – 450 °C. While its pyrolysis in a nitrogen flow reactor or in encaps...

  6. Thermal and kinetic behaviors of biomass and plastic wastes in co-pyrolysis

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • Co-pyrolysis of biomass together with the plastic wastes in thermogravimetric analyzer. • Investigations into thermal and kinetic behaviors at high temperature regions. • Determination of the kinetic parameters. - Abstract: In this study, co-pyrolysis characteristics and kinetics of biomass-plastic blends were investigated. Cotton stalk, hazelnut shell, sunflower residue, and arid land plant Euphorbia rigida, were blended in definite ratio (1:1, w/w) with polyvinyl chloride (PVC) and polyethylene terephthalate (PET). Experiments were conducted with a heating rate of 10 °C min?1 from room temperature to 800 °C in the presence of N2 atmosphere with a flow rate of 100 cm3 min?1. After thermal decomposition in TGA, a kinetic analysis was performed to fit thermogravimetric data and a detailed discussion of co-pyrolysis mechanism was achieved. Experimental results demonstrated that the structural differences between biomass and plastics directly affect their thermal decomposition behaviors. Biomass pyrolysis generally based on three main steps while plastic material’s pyrolysis mechanism resulted in two steps for PET and three steps for PVC. Also, the required activation energies needed to achieve the thermal degradation for plastic were found higher than the biomass materials. In addition, it can be concluded that the evaluation of plastic materials together with biomass created significant changes not only for the thermal behaviors but also for the kinetic behaviors

  7. Catalytic action of CuAlS2 microparticles and nanoparticles in cellulose pyrolysis

    Science.gov (United States)

    Chaki, Sunil H.; Mahato, Kanchan S.; Deshpande, M. P.

    2015-04-01

    This paper explores the catalytic action of as-synthesized CuAlS2 microparticles and nanoparticles on cellulose pyrolysis. The CuAlS2 microparticles were synthesized by heating precursor elements at high temperatures in an evacuated quartz ampoule. CuAlS2 nanoparticles were synthesized at ambient temperature by using a simple wet chemical technique. Before using the microparticles and nanoparticles for catalytic study, they were comprehensively characterized. The thermal analysis, including catalytic study of both the CuAlS2 microparticles and nanoparticles on cellulose pyrolysis, was carried out by thermogravimetric (TG), differential thermogravimetric (DTG) and differential thermal analysis (DTA) techniques. Prior to studying their role as catalysts in cellulose pyrolysis, the CuAlS2 microparticles and nanoparticles were characterized by thermal analysis in an inert N2 atmosphere. The TG analysis of as-synthesized CuAlS2 microparticles and nanoparticles showed three and five steps of decomposition, with total weight losses of 6.89% and 53.37%, respectively. The TG analysis of pure cellulose and cellulose mixed with 10%, 5% and 2.5% CuAlS2 microparticles and nanoparticles demonstrated that the nanoparticles are better catalysts in cellulose pyrolysis than the microparticles. The TG analysis results of cellulose pyrolysis have been supported by the DTA and DTG curves recorded simultaneously. The obtained results are explored in detail.

  8. In-line deoxygenation for organic carbon detections in seawater using a marine microbial fuel cell-biosensor.

    Science.gov (United States)

    Quek, Soon Bee; Cheng, Liang; Cord-Ruwisch, Ralf

    2015-04-01

    Assimilable organic carbon (AOC) is a key predictor for membrane biofouling in seawater desalination reverse osmosis (SWRO). Microbial fuel cells have been considered as biosensors for the detection of biodegradable organics. However, the presence of dissolved oxygen (DO) is known to completely suppress the signal production (i.e., current) of a typical MFC. This study describes AOC detection in normal oxygenated seawater by coupling an electrochemical cell for DO removal with a MFC-biosensor for AOC detection. The electrochemical deoxygenation for oxygen removal caused no interference in the AOC detection. A linear relationship (R(2)=0.991) between the AOC concentration and current production from the MFC biosensor was achieved. The coupling of an electrochemical cell with a MFC-biosensor can be effectively used as an online, rapid and inexpensive measure of AOC concentrations and hence as an indicator for biofouling potential of seawater. PMID:25679497

  9. Analysis of cherat coal by pyrolysis gas chromatography

    International Nuclear Information System (INIS)

    Flash pyrolysis of four representative coal samples from Cherat coal mines was studied in flowing nitrogen using quartz tubular reactor coupled to gas chromatograph with flame ionization detector. This techniques allows the on line monitoring of volatile organics released from coal during pyrolysis. The major products detected are CH/sub 4/, C/sub 2/H/sub 4/ + C/sub 2/H/sub 6/, C/sub 3/H sub 6/ + C/sub 3/H/sub 8, C/sub 4/H/sub 10 and C/sub 5/H/sub 12/. Ratios of total hydrocarbons obtained are at 700 degree C from A-5, A-4, B1 and B-6 coal samples are 3.25:2.49:3.53:1 respectively, and are characteristic of each coal. The effect of temperature on the total amount of hydrocarbons was studied over temperature range 500-800 degree C,. For all the coal samples the total amount of hydrocarbons increased with an increase in temperature and passed through a maximum. For B-6 coal samples the temperature of the maximum is 650 degree C, while for A-5, A-4 and B-1 coals, it has raised to 750 degree C. To measure the effect of inherent mineral matters on the production of hydrocarbons, pyrolysis experiments were performed at 700 degree C using raw and de-mineralized coal. Removal of inherent mineral matter showed variable effect on the total amount of observed hydrocarbon products. For coal samples A-5, A-4 and B-1 the removal of inherent mineral decrease the products yield by 15 %, 23.5% and 21.5% respectively, while for B-6 samples the acid treatment of raw coal has no effect oacid treatment of raw coal has no effect on the products yield. (author)

  10. Kinetics of pyrolysis and combustion of spherical wood particles in a fluidized bed

    International Nuclear Information System (INIS)

    Highlights: • H2, CO2, CO and CH4 released during wood pyrolysis were experimentally monitored. • CO2 formed by burning the residual tar/char mixture was experimentally determined. • The kinetics of species production was reproduced with two simplified models. • The increase of the bed reactor temperature statistically enhanced the gas yield. • The pyrolysis time is statistically reduced by decreasing the particle size. - Abstract: The kinetics of wood pyrolysis and combustion of residual fuel at different particle diameters and temperatures was investigated. A known mass of wooden spheres was fed at the top of a fluidized bed reactor filled with olivine particles and fluidized with nitrogen. The concentration of H2, CO2, CO and CH4 was on-line monitored with gas analyzers. An irreversible first order reaction was applied to describe the biomass pyrolysis. The rate constant was dependent on the average temperature of wood particle, obtained by solving the transient one-dimensional problem of heat conduction in a sphere. The rate for an irreversible second order reaction between the residual fuel and oxygen at the fluid–solid interface, which takes a finite resistance to mass transfer into account, was adopted to describe the combustion. The semi-empirical kinetic models for pyrolysis and combustion were able to describe, with certain limitations inherent to model simplifications, the experimental transient results of molar flow rates of major released species. A statistical model based on the results of the factorial design of experiments (32) confirmed a statistical significant effect of temperature and wood particle diameter on the gas yield and time of pyrolysis, respectively

  11. Bio-oil production from pyrolysis of corncob (Zea mays L.)

    International Nuclear Information System (INIS)

    Pyrolysis experiments have been conducted on a sample of corncob to determine the effects of pyrolysis temperature, heating rate and sweep gas flow rate on the pyrolysis product yields and their chemical compositions. The temperature of pyrolysis, heating rate and sweep gas flow rate were varied in the ranges of 400–550 °C, 7–40 °C min?1 and 50–200 cm3 min?1, respectively. The maximum oil yield of 26.44 wt.% was obtained at a pyrolysis temperature of 500 °C, heating rate of 40 °C min?1 and sweeping gas flow rate of 100 cm3 min?1. The elemental analysis and calorific value of the oil were determined, and the chemical composition of the oil was investigated using chromatographic and spectroscopic techniques (column chromatography, FTIR, 1H-NMR). Chromatographic and spectroscopic studies on the bio-oil showed that the bio-oil obtained from corncob could be used as a renewable fuel and chemical feedstock with a calorific value of 26.22 MJ kg?1 and empirical formula of CH1.34O0.28N0.01. -- Highlights: ? Pyrolysis of corncob was performed in a fixed-bed reactor under different conditions. ? The yield of 26.44% was obtained at a temperature of 500 °C, a heating rate of 40 °C/min and gas flow rate of 100 cm3/min. ? The oil is a mixture of aliphatic and aromatic hydrocarbons having an empirical formula of CH1.34O0.28N0.01. ? The higher calorific value of the oil is 26.22 MJ/kg, which is very close to those of petroleum fractions. ? FTIR analysis showed that the oil composition was dominated by oxygenated species.

  12. An economic analysis of mobile pyrolysis for northern New Mexico forests.

    Energy Technology Data Exchange (ETDEWEB)

    Brady, Patrick D.; Brown, Alexander L.; Mowry, Curtis Dale; Borek, Theodore Thaddeus, III

    2011-12-01

    In the interest of providing an economically sensible use for the copious small-diameter wood in Northern New Mexico, an economic study is performed focused on mobile pyrolysis. Mobile pyrolysis was selected for the study because transportation costs limit the viability of a dedicated pyrolysis plant, and the relative simplicity of pyrolysis compared to other technology solutions lends itself to mobile reactor design. A bench-scale pyrolysis system was used to study the wood pyrolysis process and to obtain performance data that was otherwise unavailable under conditions theorized to be optimal given the regional problem. Pyrolysis can convert wood to three main products: fixed gases, liquid pyrolysis oil and char. The fixed gases are useful as low-quality fuel, and may have sufficient chemical energy to power a mobile system, eliminating the need for an external power source. The majority of the energy content of the pyrolysis gas is associated with carbon monoxide, followed by light hydrocarbons. The liquids are well characterized in the historical literature, and have slightly lower heating values comparable to the feedstock. They consist of water and a mix of hundreds of hydrocarbons, and are acidic. They are also unstable, increasing in viscosity with time stored. Up to 60% of the biomass in bench-scale testing was converted to liquids. Lower ({approx}550 C) furnace temperatures are preferred because of the decreased propensity for deposits and the high liquid yields. A mobile pyrolysis system would be designed with low maintenance requirements, should be able to access wilderness areas, and should not require more than one or two people to operate the system. The techno-economic analysis assesses fixed and variable costs. It suggests that the economy of scale is an important factor, as higher throughput directly leads to improved system economic viability. Labor and capital equipment are the driving factors in the viability of the system. The break-even selling price for the baseline assumption is about $11/GJ, however it may be possible to reduce this value by 20-30% depending on other factors evaluated in the non-baseline scenarios. Assuming a value for the char co-product improves the analysis. Significantly lower break-even costs are possible in an international setting, as labor is the dominant production cost.

  13. Biomass pyrolysis in a fixed-bed reactor: Effects of pyrolysis parameters on product yields and characterization of products

    International Nuclear Information System (INIS)

    Slow pyrolysis of eastern giant fennel (Ferula orientalis L.) stalks has been performed in a fixed-bed tubular reactor with (ZnO, Al2O3) and without catalyst at six different temperatures ranging from 350 °C to 600 °C with heating rates of 15, 30, 50 °C/min. The amounts of bio-char, bio-oil and gas produced, as well as the compositions of the resulting bio-oils were determined by FT-IR and GC–MS. The effects of pyrolysis parameters such as temperature, catalyst and ratio of catalyst, particle size (Dp) and sweeping gas flow rate on product yields were investigated. According to results, temperature and catalyst seem to be the main factors effecting the conversion of F. orientalis L. into solid, liquid and gaseous products. The highest liquid yield (45.22%) including water was obtained with 15% zinc oxide catalyst at 500 °C temperature at a heating rate of 50 °C/min when 0.224 > Dp > 0.150 mm particle size raw material and 100 cm3/min of sweeping gas flow rate were used. - Highlights: • Ferula orientalis L. stalks were converted to solid, liquid and gaseous products. • Effects of various parameters on product yields were investigated. • 500 °C of temperature, heating rate of 50 °C/min and zinc oxide provide the optimum conditions for bio-oil formation. • 81 different compounds were identified by GC–MS in the bio-oils obtained at 500 °C

  14. Characterization of sedimentary organic matter by preparative pyrolysis: Comparison with rock-eval pyrolysis and pyrolysis-gas chromatography techniques

    Energy Technology Data Exchange (ETDEWEB)

    Vandenbroucke, M.; Behar, F.; Espitalie, J. (Institute Francais du Petrole, Rueil Malmaison (France))

    Estimation of petroleum potential (amount and quality) of sedimentary organic matter is now often done by pyrolyzing the organic matter and analyzing effluents. A new technique, preparative pyrolysis followed by separation and detailed analysis of saturates and unsaturates, is compared with Rock-Eval pyrolysis and pyrolysis-gas chromatography. Examples are given for the three main types of organic matter, through samples taken at the beginning of the diagenesis zone and at the beginning of the catagenesis zone. They show that preparative pyrolysis is more time-consuming than Rock-Eval or Py-GC techniques but gives a very clear differentiation between types of organic matter, even when mixtures of organic inputs or alteration problems occur, and this occurs as early as the diagenesis stage.

  15. Exploratory study on the pyrolysis and PAH emissions of polylactic acid

    Science.gov (United States)

    Chien, Yi-Chi; Liang, Chenju; Yang, Shu-hua

    2011-01-01

    The emission factors for 16 U.S. EPA priority polycyclic aromatic hydrocarbons (PAHs) from the polylactic acid (PLA) pyrolysis and the decomposition mechanism were investigated in this study. The fragments and gas compositions using on-line thermogravimetry-mass spectrometry (TG-MS) were determined. A temperature series of 7 fragments was analyzed in helium, and was found to include: m/z = 16, which may represent methane; 28, which may be carbon monoxide; 44, which may be acetaldehyde; 56, which may be methylketene, 144, which may be oligomers of lactide. In addition, there are little amount of 100, and 200 which are oligomers of lactides observed in the pyrolysis of PLA. The pyrolysis of PLA is a non-radical, backbiting ester interchange reaction involving the OH chain ends. Depending on the size of the cyclic transition state, the product can be a lactide molecule, an oligomeric ring with more than two repeat units, methylketene, or acetaldehyde. Carbon monoxide and methane are contributions from the decomposition of acetaldehyde. Experimentally, not detected (n.d.)-40.47 ?g of 16 PAH emissions were determined from per gram of PLA pyrolysis. The PAH profiles showed a predominance of naphthalene (58.9%), phenanthrene (12.5%), and fluoranthene (5.9%). The total PAH emissions for PLA pyrolysis is significantly lower than the values associated with PLA combustion. From the viewpoint of air pollution control, this result suggests that pyrolysis seems a better alternative than combustion for the disposal of waste PLA. Also, since pyrolysis is the first step for an incineration process, these results can provide important information on the control of PAHs formation for a commercialized incinerator.

  16. Fast pyrolysis of microalgae in a falling solids reactor: Effects of process variables and zeolite catalysts

    International Nuclear Information System (INIS)

    Non-catalytic and catalytic pyrolysis of microalgae were carried out to generate an organic liquid fuel precursor. The impacts of several process variables on the fast pyrolysis in a falling solids reactor are reported, including temperature, particle size, flow rate, and atmosphere (N2, H2O and CO2). Experiments were carried out with duckweed as the biomass to provide some comparison. The speciated organic phase product data were classified according to the different compound types including hydrocarbons, alcohols, oxygenates, and nitrogenates. In-situ catalytic pyrolysis produced an organic phase with an increased fraction of hydrocarbons and decreased fraction of oxygenates, evidence for carbon removal chemistries such as decarboxylation and decarbonylation. The noncatalytic pyrolysis gave the highest total liquid yield while catalytic pyrolysis resulted in the highest yield of the desired hydrocarbon fraction. A comparison of four exchanged ZSM-5 catalysts (H-, Fe-, Cu-, and Ni-) indicates that the protonated zeolite provided the largest enhancement among the catalysts of the liquid product yield and composition: H-ZSM-5 increased the yield of the hydrocarbon fraction in the organic phase from 21% to 43%, a 100% relative increase, and exhibited the least coking. The effects of biomass weight hourly space velocity, and comparisons between H-ZSM5 powder and monolithic catalysts are also reported. The implications of the findings for the conversion of microalgae to liquid fuels are discussed. -- Graphical abstract: Display Omitted Highlights: ? Pyrolysis of microalgae and duckweed in falling solids reactor. ? Effect of process variables on product yields and compositions determined. ? Catalytic pyrolysis enhances bio-oil composition. ? Shape selective ZSM-5 catalysts enhance hydrocarbon yield.

  17. Influence of reaction conditions on fast pyrolysis of macroalge

    International Nuclear Information System (INIS)

    Full text: The importance of renewable energy sources has increased rapidly due to the high international crude oil prices and environmental concerns over fossil fuel use. Recently, there has been a growing interest in aquatic biomass, especially marine macro algae, and a number of studies have been initiated to evaluate its potential for bio-energy. This paper reports a fast pyrolysis of macro algae under different reaction conditions such as pyrolysis temperature, particle size and sample quantity. Various macro algae such as Undaria pinnatifida, Laminaria japonica and Porphyra tenera were fast pyro lysed at temperatures between 300-600 degree Celsius in a batch reactor and the main product of bio-oil was obtained. The optimal reaction temperature for the production of bio-oil was 500 degree Celsius. At this temperature, the maximum bio-oil yields were 40.4 wt % ( by Undaria pinnatifida), 37.6 wt % (by Laminaria japonica) and 47.4 wt % (by Porphyra tenera), respectively. In particular, after pre-treatment with 2.0M HCl solution, the product yield of bio-oil was increased in macro algae, Undaria pinnatifida. The pyroylsis gases were analyzed by using GC-TCD and GC-FID and qualitative analyses of bio-oil were performed using GC-MS. The maximum yield of bio-oil, Undaria pinnatifida, Laminaria japonica and Porphyra tenera, was obtained at 500 degree Celsius (40.4 wt %, 37.6 wt % and 47.4 wt %, respectively). (author)

  18. Surface Pyrolysis of High Energy Materials

    Directory of Open Access Journals (Sweden)

    Luigi Deluca

    1998-10-01

    Full Text Available The Arrhenius zero-order phenomenological pyrolysis law, commonly used in conjunction with the Vieille ballistic law to study pressure-driven burning of energetic materials, is revisited. Motivated by experimental and theoretical work performed in 1984 in this Laboratory , a relationship among several interplaying parameters is found under steady-state conditions. This relationship corresponds to the Jacobian of the pyrolysis sensitivity parameters used in the Zeldovich-Novozhilov approach. The Arrhenius pyrolysis is still expressed in terms of a global surface activation energy, but consistency with the experimental ballistic law may require an explicit pressure dependence as well. This conclusion is supported by a variety of arguments drawn from different areas. The linear dependence of the pre-exponential factor on surface activation energy (known as kinetic compensation is proved and extended to the pressure exponent, for any given experimental data set under steady burning. Experimental results are reported for about a dozen solid propellants of different nature. The effects of surface pyrolysis explicit pressure dependence, although modest on steady-state burning, are potentially far-reaching for unsteady regime and/or unstable burning. The paper is mainly focussed on pressure-driven burning and Arrhenius pyrolysis, but the implemented method is believed to apply in general. Thus, enforcing KTSS zero-order phenomenological pyrolysis with the Vieille ballistic law yields similar results and requires an explicit pressure dependence. In case, the Zeldovich ballistic law is enforced instead of the classical Vieille law, no explicit pressure dependence is required. The unifying concept for these different trends is the pyrolysis Jacobian as a consistency requirement between the implemented steady pyrolysis and ballistic laws."

  19. Photocatalytic Desulfurization of Waste Tire Pyrolysis Oil

    OpenAIRE

    Napida Hinchiranan; Prasert Reubroycharoen; Phakakrong Trongkaew; Thanes Utistham

    2011-01-01

    Waste tire pyrolysis oil has high potential to replace conventional fossil liquid fuels due to its high calorific heating value. However, the large amounts of sulfurous compounds in this oil hinders its application. Thus, the aim of this research was to investigate the possibility to apply the photo-assisted oxidation catalyzed by titanium dioxide (TiO2, Degussa P-25) to partially remove sulfurous compounds in the waste tire pyrolysis oil under milder reaction conditions without hydrogen cons...

  20. Pyrolysis of D-Glucose to Acrolein

    Science.gov (United States)

    Shen, Chong; Zhang, Igor Ying; Fu, Gang; Xu, Xin

    2011-06-01

    Despite of its great importance, the detailed molecular mechanism for carbohydrate pyrolysis remains poorly understood. We perform a density functional study with a newly developed XYG3 functional on the processes for D-glucose pyrolysis to acrolein. The most feasible reaction pathway starts from an isomerization from D-glucose to D-fructose, which then undergoes a cyclic Grob fragmentation, followed by a concerted electrocyclic dehydration to yield acrolein. This mechanism can account for the known experimental results.

  1. Barium strontium titanate powders prepared by spray pyrolysis

    International Nuclear Information System (INIS)

    Ultasonic spray pyrolysis (SP) has been investigated for the production of the barium strontium titanate (BST) powders from the polymeric precursors. The processing parameters, such as flux of aerosol and temperature profile inside the furnace, were optimized to obtain single phase BST. The powders were characterized by the methods of X-ray diffraction analysis, SEM, EDS and TEM. The obtained powders were submicronic, consisting of spherical, polycrystalline particles, with internal nanocrystalline structure. Crystallite size of 10 nm, calculated using Rietveld refinement, is in a good agreement with results of HRTEM

  2. Characterization of some Jordanian oil shales by pyrolysis gas chromatography

    International Nuclear Information System (INIS)

    Gas chromatography with flame ionization detector (GC-FID) was used to study pyrolysis of some Jordanian oil shale samples. Three sampls of different altitudes from El-Lajjun were studied. Pyrograms of solid sampls were studied at different temperature profiles. Solid-liquid extraction with water, methanol, or hexane allowed extraction of organics of different polarity. Hexane showed the highest extraction efficiency. Reproducibility of the pyrograms of the solid sample was evalualted. Relative standard deviation was 7.56%. (author). 7 refs., 8 figs

  3. Characterization of Pakistani coal by pyrolysis gas chromatography

    International Nuclear Information System (INIS)

    Flash pyrolysis were carried out for two samples of Shariagh Top Seam and Middle Seam coal in flowing NItrogen. The influence of temperature on the hydrocarbon yields was explored from 500-800 C with vapour product residence time of 0.46 sec. The principal products observed were methane, ethane hydrocarbon/3, hydrocarbon/4, cyclo pentane, benzene and toluene. The effect of changing particle size (30-50 mesh) and sample size (2-8 mg) on the yield of observed products was studied at 700 C. (author)

  4. Test plan for ISV laboratory-pyrolysis testing

    Energy Technology Data Exchange (ETDEWEB)

    McAtee, R.E.

    1991-09-01

    The objective of the laboratory-pyrolysis studies is to obtain information on the high temperature (< 1200{degree}C) degradation and alteration of organic chemicals and materials similar to those found in the Radioactive Waste Management Complex, Pit 9. This test plan describes experimental procedures, sampling and analysis strategy, sampling procedures, sample control, and document management. It addresses safety issues in the experimental apparatus and procedures, personal training, and hazardous waste disposal. Finally, it describes the data quality objectives using the EPA tiered approach to treatability studies to define where research/scoping tests fit into these studies and the EPA analytical levels required for the tests.

  5. Thermal History Of PMRs Via Pyrolysis-Gas Chromatography

    Science.gov (United States)

    Gluyas, Richard E.; Alston, William B.; Snyder, William J.

    1994-01-01

    Pyrolysis-gas chromatography (PY-GC) useful as analytical technique to determine extents of cure or postcure of PMR-15 polyimides and to lesser extent, cumulative thermal histories of PMR-15 polyimides exposed to high temperatures. Also applicable for same purposes to other PMR polyimides and to composite materials containing PMR polyimides. Valuable in reducing costs and promoting safety in aircraft industry by helping to identify improperly cured or postcured PMR-15 composite engine and airframe components and helping to identify composite parts nearing ends of their useful lives.

  6. Pyrolysis of Sawdust, Rice Husk and Sugarcane Bagasse: Kinetic Modeling and Estimation of Kinetic Parameters using Different Optimization Tools

    Science.gov (United States)

    Khonde, Ruta Dhanram; Chaurasia, Ashish Subhash

    2015-04-01

    The present study provides the kinetic model to describe the pyrolysis of sawdust, rice-husk and sugarcane bagasse as biomass. The kinetic scheme used for modelling of primary pyrolysis consisting of the two parallel reactions giving gaseous volatiles and solid char. Estimation of kinetic parameters for pyrolysis process has been carried out for temperature range of 773-1,173 K. As there are serious issues regarding non-convergence of some of the methods or solutions converging to local-optima, the proposed kinetic model is optimized to predict the best values of kinetic parameters for the system using three approaches—Two-dimensional surface fitting non-linear regression technique, MS-Excel Solver Tool and COMSOL software. The model predictions are in agreement with experimental data over a wide range of pyrolysis conditions. The estimated value of kinetic parameters are compared with earlier researchers and found to be matching well.

  7. Pyrolysis of Sawdust, Rice Husk and Sugarcane Bagasse: Kinetic Modeling and Estimation of Kinetic Parameters using Different Optimization Tools

    Science.gov (United States)

    Khonde, Ruta Dhanram; Chaurasia, Ashish Subhash

    2015-01-01

    The present study provides the kinetic model to describe the pyrolysis of sawdust, rice-husk and sugarcane bagasse as biomass. The kinetic scheme used for modelling of primary pyrolysis consisting of the two parallel reactions giving gaseous volatiles and solid char. Estimation of kinetic parameters for pyrolysis process has been carried out for temperature range of 773-1,173 K. As there are serious issues regarding non-convergence of some of the methods or solutions converging to local-optima, the proposed kinetic model is optimized to predict the best values of kinetic parameters for the system using three approaches—Two-dimensional surface fitting non-linear regression technique, MS-Excel Solver Tool and COMSOL software. The model predictions are in agreement with experimental data over a wide range of pyrolysis conditions. The estimated value of kinetic parameters are compared with earlier researchers and found to be matching well.

  8. Spray pyrolysis deposition of lanthanum telluride thin films and their characterizations

    International Nuclear Information System (INIS)

    Spray pyrolysis method is used to deposit lanthanum telluride (La2Te3) thin films on glass substrates. The films are deposited by pyrolysis of sprayed solutions of LaCl3 and Te metal dissolved in concentrated HCl and HNO3 along with hydrazine hydrate as a reducing agent. X-ray diffraction analyses show that the films are polycrystalline with La2Te3 phase. The films have a direct optical band gap of 2.2 eV. The films are p-type semiconductors with an electrical resistivity of the order of 104 ? cm at ambient temperature (27 deg. C)

  9. Release of chlorine from biomass at pyrolysis and gasification conditions, part 2

    International Nuclear Information System (INIS)

    Results from pyrolysis experiment with some biomass materials and pure cellulose shows that the chlorine evaporates from different fuels in two steps. The second of these steps can be explained as evaporation of KCl or other volatile chlorides. The first step starts at temperature levels 300-400 deg C which is too low for salt volatilization. Anyhow, the materials releases up to 50% of the total fuel chlorine in this first step. To explain this first step a mechanism has been suggested in which the chlorine during pyrolysis can be transferred to hydrogen chloride 4 refs, 9 figs

  10. Site-Specific Pyrolysis Induced Cleavage at Aspartic Acid Residue in Peptides and Proteins

    OpenAIRE

    Zhang, Shaofeng; Basile, Franco

    2007-01-01

    A simple and site-specific non-enzymatic method based on pyrolysis has been developed to cleave peptides and proteins. Pyrolytic cleavage was found to be specific and rapid as it induced a cleavage at the C-terminal side of aspartic acid in the temperature range of 220–250 °C in 10 seconds. Electrospray Ionization (ESI) mass spectrometry (MS) and tandem-MS (MS/MS) were used to characterize and identify pyrolysis cleavage products, confirming that sequence information is conserved after the py...

  11. Experimental Flash Pyrolysis of High Density PolyEthylene under Hybrid Propulsion Conditions

    OpenAIRE

    Gascoin, Nicolas; Fau, Guillaume; Gillard, Philippe; Mangeot, Alexandre

    2013-01-01

    The inert and oxidative flash pyrolysis of High Density Poly-Ethylene (HDPE) is studied up to 20 000 K.s-1, under pressure up to 3.0 MPa and at temperature ranging from 1000 K to 1500 K. These conditions are considered to represent those waited onboard a hybrid rocket engine using HDPE as solid fuel. Recycling applications may also find some interest. The pyrolysis products are quantified by Gas Chromatograph, Flame Ionisation Detector and Mass Spectrometer to determine the effects of each ph...

  12. Recovery of hydrocarbon liquid from waste high density polyethylene by thermal pyrolysis

    OpenAIRE

    Sachin Kumar; R.K. Singh

    2011-01-01

    Thermal degradation of waste plastics in an inert atmosphere has been regarded as a productive method, because this process can convert waste plastics into hydrocarbons that can be used either as fuels or as a source of chemicals. In this work, waste high-density polyethylene (HDPE) plastic was chosen as the material for pyrolysis. A simple pyrolysis reactor system has been used to pyrolyse waste HDPE with the objective of optimizing the liquid product yield at a temperature range of 400ºC to...

  13. Mn-Doped Zn2SiO4 Phosphors Synthesis Using Flame Spray Pyrolysis

    Science.gov (United States)

    Lee, Jae Seok; Oh, Myoung Hwan; Kumar, Purushottam; Khanna, Aniruddh; Singh, Rajiv K.; Ranade, Madhav B.

    2011-09-01

    Zn2SiO4:Mn2+ particles are used as green phosphors in plasma display panels and cathode ray tubes. In this study, we report the synthesis of zinc silicate phosphors by flame spray pyrolysis using different Zn-sources and under different process conditions. The XRD and luminescence measurement showed the phosphors prepared from Zn-nitrate source to have better crystallinity and emission characteristics. The luminescence properties of the phosphor particles were found to improve both at higher methane flow rates during pyrolysis and at higher annealing temperatures.

  14. Linking ramped pyrolysis isotope data to oil content through PAH analysis

    Science.gov (United States)

    Pendergraft, Matthew A.; Dincer, Zeynep; Sericano, José L.; Wade, Terry L.; Kolasinski, Joanna; Rosenheim, Brad E.

    2013-12-01

    Ramped pyrolysis isotope (13C and 14C) analysis coupled with polycyclic aromatic hydrocarbon (PAH) analysis demonstrates the utility of ramped pyrolysis in screening for oil content in sediments. Here, sediments from Barataria Bay, Louisiana, USA that were contaminated by oil from the 2010 BP Deepwater Horizon spill display relationships between oil contamination, pyrolysis profiles, and isotopic composition. Sediment samples with low PAH concentrations are thermochemically stable until higher temperatures, while samples containing high concentrations of PAHs pyrolyze at low temperatures. High PAH samples are also depleted in radiocarbon (14C), especially in the fractions that pyrolyze at low temperatures. This lack of radiocarbon in low temperature pyrolyzates is indicative of thermochemically unstable, 14C-free oil content. This study presents a proof of concept that oil contamination can be identified by changes in thermochemical stability in organic material and corroborated by isotope analysis of individual pyrolyzates, thereby providing a basis for application of ramped pyrolysis isotope analysis to samples deposited in different environments for different lengths of time.

  15. Change of physical and chemical properties of the solid phase during biomass pyrolysis; Aenderung der physikalisch-chemischen Eigenschaften des Feststoffs waehrend der Biomassepyrolyse

    Energy Technology Data Exchange (ETDEWEB)

    Klose, Wolfgang [Kassel Univ. (Germany). Inst. fuer Thermische Energietechnik; Rincon, Sonia; Gomez, Alexander [Universidad Nacional de Colombia, Bogota (Colombia). Dept. de Ingenieria Mecanica y Mecatronica

    2009-01-15

    The effects of the final pyrolysis temperature on the development of the chemical composition and on the porosity of biomass undergoing pyrolysis are investigated through experiments in a thermobalance at laboratory scale of grams. Changes in the grain size of individual particles of biomass during pyrolysis are also investigated as a function of temperature in a microscope equipped with heating and camera. Oil palm shells are selected as raw materials due to their availability as biomass residue and their physical and chemical characteristics. These experiments are important for reactor design purposes in the field of thermochemical conversion, offering important information for the mathematical modelling of the processes. (orig.)

  16. Kinetic Study of the Pyrolysis of Waste Printed Circuit Boards Subject to Conventional and Microwave Heating

    Directory of Open Access Journals (Sweden)

    Chunyuan Ma

    2012-08-01

    Full Text Available This paper describes a kinetic study of the decomposition of waste printed circuit boards (WPCB under conventional and microwave-induced pyrolysis conditions. We discuss the heating rates and the influence of the pyrolysis on the thermal decomposition kinetics of WPCB. We find that the thermal degradation of WPCB in a controlled conventional thermogravimetric analyzer (TGA occurred in the temperature range of 300 °C–600 °C, where the main pyrolysis of organic matter takes place along with an expulsion of volumetric volatiles. The corresponding activation energy is decreased from 267 kJ/mol to 168 kJ/mol with increased heating rates from 20 °C/min to 50 °C/min. Similarly, the process of microwave-induced pyrolysis of WPCB material manifests in only one stage, judging by experiments with a microwave power of 700 W. Here, the activation energy is determined to be only 49 kJ/mol, much lower than that found in a conventional TGA subject to a similar heating rate. The low activation energy found in microwave-induced pyrolysis suggests that the adoption of microwave technology for the disposal of WPCB material and even for waste electronic and electrical equipment (WEEE could be an attractive option.

  17. Application of Gamma Radiation on Bio-oil Produced from Pyrolysis of Soybean Cake

    International Nuclear Information System (INIS)

    Soybean cake residue from soy milk making can be pyrolysed to produce pyrolysis liquid or bio-oil which has potency to be used as liquid fuel. Pyrolysis of soybean cake residue with the application of gamma irradiation was investigated in a batch reactor at 450°C for 1.5 hr under nitrogen flow 250 cc/min. Feed of soybean cake residue was exposed to gamma radiation at the doses of 200 to 1,000 kGy before pyrolysing. It was found that pyrolysis liquid yield increased significantly by 12.9 to 19.3 % at the irradiation doses of 400 kGy and higher. The increment was mainly due to the increasing of aqueous phase in the pyrolysis liquid. The heating value of organic phase in the pyrolysis liquid was 7,890 kcal/kg. The organic phase from the unexposed feed was also irradiated at 20-100 kGy. The viscosity of irradiated organic phase was found to increase with the increasing irradiation dose. Irradiated organic phase was distilled at temperatures 200 and 250°C. It was found that the first distilled fraction (<200°C) corresponding to gasoline fraction increased with the increasing irradiation dose while the second distilled fraction (200-250°C) corresponding to kerosene fraction seems to decrease. The composition of organic phase was also determined by GC-MS.

  18. Pyrolysis treatment of oil sludge and model-free kinetics analysis

    International Nuclear Information System (INIS)

    Pyrolysis of tank bottom oil sludge was investigated to summarize the pyrolysis characteristics through analyzing the change of mass loss, pyrolysis gas compositions in heating process. For this propose, various approaches including thermogravimetric analysis (TGA), CNHS/O elemental analysis, electrically heated fixed bed quartz reactor coupled with Vario Plus emission monitoring system, and oil-gas evaluation workstation (OGE-II) equipped with a flame ionization detector (FID) were used. The pyrolysis reaction is significant in the range of 473-773 K where multi-peak DTG curves can be gained. Higher heating rate increases the carbon (C) and sulfur (S) contents but decreases hydrogen (H) content in solid residues. The major gaseous products excluding N2 are CHs (Hydrocarbons), CO2, H2, CO. The yield of CHs is significant in the range of 600-723 K. Higher heating rate causes the peak intensity of CHs evolution to increase and the CHs evolution to move towards a high-temperature region. Around 80% of total organic carbon content (TOC) in oil sludge can be converted into CHs in pyrolysis process. The CHs data were used for kinetic analysis by Vyazovkin model-free iso-conversion approach. Dependences of the activation energy on the degree of conversion obtained from different methods were compared

  19. Synthesis of advanced materials for bio-oil production from rice straw by pyrolysis

    International Nuclear Information System (INIS)

    Bio-oil from rice straw is produced by pyrolysis with and without solid acid catalysts. Solid acid catalysts used in rice straw pyrolysis synthesis were the diatomite acidified by an 'atomic implantation method' and nano-sized porous Al-SBA1 -15. Catalysts were characterized by a field emission-scanning electron microscope (FE-SEM), transmission electron microscopy (TEM), x-ray diffraction (XRD), infrared spectroscopy (IR), N2 adsorption/desorption, differential thermal analysis/thermogravimetric analysis (DTA/TGA) and NH3 temperature programmed desorption (NH3-TPD). The obtained results revealed that a similar bio-oil yield (liquid product) of 44–48% can be reached by pyrolysis in the presence of solid acid catalysts at 450?°C compared to that of pyrolysis without catalyst at 550?°C. Moreover, a low yield of gas product was observed. These results show significant potential applications of solid acid catalysts for the improvement of bio-oil yield in the pyrolysis of rice straw

  20. Role of mineral matrix in kerogen pyrolysis: influence on petroleum generation and migration

    Energy Technology Data Exchange (ETDEWEB)

    Espitalie, J.; Madec, M.; Tissot, B.

    1980-01-01

    Comparable pyrolysis experimentals have been performed on rocks containing organic matter and on related kerogens which were separated from the rock by acid treatment. In some examples, hydrocarbon yields from the rocks are lower. The experimental procedure separates the lighter hydrocarbons (lower than C/sub 15/) from total hydrocarbons, thus showing that the decreased hydrocarbon yield from rocks as compared to kerogen is principally due to retention of the heaviest hydrocarbons. The light hydrocarbons do not seem to be reduced in quantity. By studying mixtures of kerogens with various minerals, we infer that retention of heavy hydrocarbon products issued from the kerogen pyrolysis occurs on the mineral surfaces. With increasing temperature and time, the trapped hydrocarbons may be cracked: light hydrocarbons are released, whereas a carbon residue remains on minerals. Some of the argillaceous minerals used (illite from Le Puy, France) are particularly active whereas other minerals such as carbonates show weak activity. Pyrolysis performed on many samples of rocks confirms these experimental assays and shows that hydrocarbon retention during pyrolysis increases with the clay content of rocks. In rocks with a low organic carbon content, these phenomena can affect the quantity of heavy hydrocarbons liberated during pyrolysis whereas the lightest hydrocarbons are little affected. Thus, under comparable geologic conditions, certain types of source rocks would release light oil and gas. 12 figures, 2 tables.

  1. A ceramic matrix composite based on polymerization and pyrolysis of ethynylated aromatics

    Science.gov (United States)

    Hurwitz, F. I.

    1985-01-01

    A number of ethynylated aromatic monomers recently have been synthesized which thermally homopolymerize and copolymerize to produce rigid, highly cross-linked polymers with high thermal stability (Tg of about 450 C). On pyrolysis, these polymers lose few volatiles (more than 85 percent char yield) to yield carbon bodies of relatively low porosity. These properties render the ethynylated aromatics of significant interest as matrices for high temperature composites. Incorporation of a SiC particle filler in the matrix improves the rheology of the system and minimizes shrinkage during pyrolysis. Several unidirectional composites have been fabricated combining a graphite or boria-alumina-silica continuous reinforcement with an ethynylated aromatic polymer matrix and SiC filler. Thermogravimetric analysis of composite pyrolysis behavior was used to determine reaction kinetics and to establish a composite fabrication cycle. Composites retained 95 percent of their green weight on pyrolysis. Microstructure of the green and pyrolyzed composites is characterized for materials pyrolyzed at 600 C in vacuum and argon as well as for laminates heated at 1200 C in argon following pyrolysis.

  2. Valorization of cotton stalks by fast pyrolysis and fixed bed air gasification for syngas production as precursor of second generation biofuels and sustainable agriculture.

    Science.gov (United States)

    Kantarelis, E; Zabaniotou, A

    2009-01-01

    In the present study, the potential of cotton stalks utilization for H(2) and syngas production with respect to CO(2) mitigation, by means of thermochemical conversion (pyrolysis and gasification) was investigated. Pyrolysis was conducted at temperature range of 400-760 degrees C and the main parametric study concerned the effect of temperature on pyrolysis product distribution. Atmospheric pressure, air gasification at 750-950 degrees C for various lambda (0.02-0.07) was also studied. Experimental results showed that high temperature favors gas production in both processes; while low lambda gasification gave high gas yield. Syngas (CO and H(2)) was increased with temperature, while CO(2) followed an opposite trend. By pyrolysis, higher H(2) concentration in the produced gas (approximately 39% v/v) was achieved and at the same time lower amounts of CO(2) produced, compared to air gasification. PMID:18783941

  3. Characterisation and Evaluation of Wastes for Treatment in the Batch Pyrolysis Plant in Studsvik, Sweden - 13586

    Energy Technology Data Exchange (ETDEWEB)

    Lindberg, Maria; Oesterberg, Carl; Vernersson, Thomas [Studsvik Nuclear AB, Studsvik Nuclear AB, 611 82 Nykoeping (Sweden)

    2013-07-01

    The new batch pyrolysis plant in Studsvik is built primarily for treatment of uranium containing dry active waste, 'DAW'. Several other waste types have been identified that are considered or assumed suitable for treatment in the pyrolysis plant because of the possibility to carefully control the atmosphere and temperature of the thermal treatment. These waste types must be characterised and an evaluation must be made with a BAT perspective. Studsvik have performed or plan to perform lab scale pyrolysis tests on a number of different waste types. These include: - Pyrophoric materials (uranium shavings), - Uranium chemicals that must be oxidised prior to being deposited in repository, - Sludges and oil soaks (this category includes NORM-materials), - Ion exchange resins (both 'free' and solidified/stabilised), - Bitumen solidified waste. Methodology and assessment criteria for various waste types, together with results obtained for the lab scale tests that have been performed, are described. (authors)

  4. Pyrolysis of biomass and refuse-derived fuel performance in laboratory scale batch reactor

    Directory of Open Access Journals (Sweden)

    Kluska Jacek

    2014-03-01

    Full Text Available The results of pyrolysis of pine chips and refuse derived fuel fractions are presented. The experiments were carried out in a pilot pyrolysis reactor. The feedstock was analyzed by an elemental analyzer and the X-ray fluorescence spectrometer to determine the elemental composition. To find out optimum conditions for pyrolysis and mass loss as a function of temperature the thermogravimetric analysis was applied. Gases from the thermogravimetric analysis were directed to the infrared spectrometer using gas-flow cuvette to online analysis of gas composition. Chemical composition of the produced gas was measured using gas chromatography with a thermal conductivity detector and a flame ionization detector. The product analysis also took into account the mass balance of individual products.

  5. Pyrolysis behaviors of four lignin polymers isolated from the same pine wood.

    Science.gov (United States)

    Wang, Shurong; Ru, Bin; Lin, Haizhou; Sun, Wuxing; Luo, Zhongyang

    2015-04-01

    Four lignin polymers, alkali lignin (AL), klason lignin (KL), organosolv lignin (OL), and milled wood lignin (MWL), were isolated from the same pine wood. Structural characterization by FTIR and (13)C NMR indicated that the four lignins have different structural features. Their pyrolysis behaviors were analyzed by TG-FTIR and Py-GC/MS. Thermally unstable ether bonds and side branches were well-preserved in AL and MWL, but were broken in OL and KL. Pyrolysis of AL and KL produce more phenols at low temperature by the breakage of ether bonds. AL and KL show lower activation energies in the main degradation stage, quantified by a distribution activation energy model with two linearly combined Gaussian functions. The evolution behaviors of typical gaseous products, CH4, CO2, and CO, were analyzed, and insights about the correlation between chemical structure and pyrolysis behavior were obtained. PMID:25686545

  6. Modelling solid-convective flash pyrolysis of straw and wood in the Pyrolysis Centrifuge Reactor

    DEFF Research Database (Denmark)

    Bech, Niels; Larsen, Morten Boberg

    2009-01-01

    Less than a handful of solid-convective pyrolysis reactors for the production of liquid fuel from biomass have been presented and for only a single reactor a detailed mathematical model has been presented. In this article we present a predictive mathematical model of the pyrolysis process in the Pyrolysis Centrifuge Reactor, a novel solid-convective flash pyrolysis reactor. The model relies on the original concept for ablative pyrolysis of particles being pyrolysed through the formation of an intermediate liquid compound which is further degraded to form liquid organics, char, and gas. To describe the kinetics of the pyrolysis reactions the Broido-Shafizadeh scheme is employed with cellulose parameters for wood and modified parameters for straw to include the catalytic effect of its alkali-containing ash content. The model describes the presented experimental results adequately for engineering purposes for both wood and straw feedstock even though conditions for ablative pyrolysis from a reaction engineering point of view are not satisfied. Accordingly, even though the concept of an ablatively melting particle may constitute a limiting case, it can still be used to model flash pyrolysis provided that the reacting particle continuously shed the formed char layer.

  7. Pyrolysis characteristics and kinetics of Arundo donax using thermogravimetric analysis.

    Science.gov (United States)

    Jeguirim, Mejdi; Trouvé, Gwenaelle

    2009-09-01

    The increase of the price of fossil means, as well as their programmed disappearing, contributed to increase among appliances based on biomass and energy crops. The thermal behavior of Arundo donax by thermogravimetric analysis was studied under inert atmosphere at heating rates ranging from 5 to 20 degrees C min(-1) from room temperature to 750 degrees C. Gaseous emissions as CO(2), CO and volatile organic compounds (VOC) were measured and global kinetic parameters were determined during pyrolysis with the study of the influence of the heating rate. The thermal process describes two main phases. The first phase named active zone, characterizes the degradation of hemicellulose and cellulose polymers. It started at low temperature (200 degrees C) comparatively to wood samples and was finished at 350 degrees C. The pyrolysis of the lignin polymer occurred during the second phase from 350 to 750 degrees C, named passive zone. Carbon oxides are emitted during the active zone whereas VOC are mainly formed during the passive zone. Mass losses, mass loss rates and emission factors were strongly affected by the variation of the heating rate in the active zone. It was found that the global pyrolysis of A. donax can be satisfactorily described using global independent reactions model for hemicellulose and cellulose in the active zone. The activation energy for hemicellulose was not affected by a variation of the heating rate with a value close to 110 kJ mol(-1) and presented a reaction order close to 0.5. An increase of the heating rate decreased the activation energy of the cellulose. However, a first reaction order was observed for cellulose decomposition. The experimental results and kinetic parameters may provide useful data for the design of pyrolytic processing system using A. donax as feedstock. PMID:19362825

  8. Rates and Mechanisms of Oil Shale Pyrolysis: A Chemical Structure Approach

    Energy Technology Data Exchange (ETDEWEB)

    Fletcher, Thomas; Pugmire, Ronald

    2015-01-01

    Three pristine Utah Green River oil shale samples were obtained and used for analysis by the combined research groups at the University of Utah and Brigham Young University. Oil shale samples were first demineralized and the separated kerogen and extracted bitumen samples were then studied by a host of techniques including high resolution liquid-state carbon-13 NMR, solid-state magic angle sample spinning 13C NMR, GC/MS, FTIR, and pyrolysis. Bitumen was extracted from the shale using methanol/dichloromethane and analyzed using high resolution 13C NMR liquid state spectroscopy, showing carbon aromaticities of 7 to 11%. The three parent shales and the demineralized kerogens were each analyzed with solid-state 13C NMR spectroscopy. Carbon aromaticity of the kerogen was 23-24%, with 10-12 aromatic carbons per cluster. Crushed samples of Green River oil shale and its kerogen extract were pyrolyzed at heating rates from 1 to 10 K/min at pressures of 1 and 40 bar and temperatures up to 1000?C. The transient pyrolysis data were fit with a first-order model and a Distributed Activation Energy Model (DAEM). The demineralized kerogen was pyrolyzed at 10 K/min in nitrogen at atmospheric pressure at temperatures up to 525?C, and the pyrolysis products (light gas, tar, and char) were analyzed using 13C NMR, GC/MS, and FTIR. Details of the kerogen pyrolysis have been modeled by a modified version of the chemical percolation devolatilization (CPD) model that has been widely used to model coal combustion/pyrolysis. This refined CPD model has been successful in predicting the char, tar, and gas yields of the three shale samples during pyrolysis. This set of experiments and associated modeling represents the most sophisticated and complete analysis available for a given set of oil shale samples.

  9. The Building and Commissioning of the Batch Pyrolysis Plant in Studsvik, Sweden - 12447

    International Nuclear Information System (INIS)

    After a sequence of lab scale and bench scale trials the building of a pyrolysis plant could begin at the Studsvik site in Sweden. The facility is primarily aimed at treatment of uranium contaminated organic waste originating at fuel manufacturing plants and other facilities where the main contamination is uranium. The plant is an extension/addition to the already operating incinerator. In order to further widen the waste acceptance criteria the design of the off-gas treatment system does not have the same design as that of the incinerator. The building of the facility began in April 2011, and the first heating of the facility took place in late December, 2011. The site acceptance tests are planned for January, as are the first inactive trials aimed at optimisation of process control. The facility is planned to be operating with radioactive materials from February 2012. The pyrolysis unit is primarily aimed at treatment of uranium contaminated waste, under conditions that facilitate leaching and recovery of the uranium from the ashes. However, a number of other uses are conceivable. The batch fed pyrolysis unit, with its chosen design of the off-gas treatment system, enables treatment of some waste fractions that are difficult to treat in the incinerator. For instance small campaigns, i.e. smaller quantities of waste (typically <5 tonnes), or waste containing high levels of chlorine and sulphur are possible to treat in the pyrolysis unit. The pyrolysis unit is also expected to perform well in the treatment of other 'difficult' waste fractions, for instance waste containing pyrophoric materials, or other types of waste that benefit from the high level of process control, i.e. control of temperature and atmosphere throughout the process, that can be obtained in the pyrolysis unit compared to the incinerator. Furthermore, treatment in the pyrolysis unit minimises the risk of cross contamination between different waste treatment campaigns. This feature is obtained thanks to the low gas flow rates in the vessel, which means that a higher retention of nuclides in the ashes is obtained, but also through a design that facilitates cleaning of the pyrolysis vessel and the system beyond this, or even exchanging the most critical components, such as the pyrolysis vessel itself, if need be. (authors)

  10. Recovery of hydrocarbon liquid from waste high density polyethylene by thermal pyrolysis

    Scientific Electronic Library Online (English)

    Sachin, Kumar; R. K., Singh.

    2011-12-01

    Full Text Available Thermal degradation of waste plastics in an inert atmosphere has been regarded as a productive method, because this process can convert waste plastics into hydrocarbons that can be used either as fuels or as a source of chemicals. In this work, waste high-density polyethylene (HDPE) plastic was chos [...] en as the material for pyrolysis. A simple pyrolysis reactor system has been used to pyrolyse waste HDPE with the objective of optimizing the liquid product yield at a temperature range of 400ºC to 550ºC. Results of pyrolysis experiments showed that, at a temperature of 450ºC and below, the major product of the pyrolysis was oily liquid which became a viscous liquid or waxy solid at temperatures above 475ºC. The yield of the liquid fraction obtained increased with the residence time for waste HDPE. The liquid fractions obtained were analyzed for composition using FTIR and GC-MS. The physical properties of the pyrolytic oil show the presence of a mixture of different fuel fractions such as gasoline, kerosene and diesel in the oil.

  11. Recovery of hydrocarbon liquid from waste high density polyethylene by thermal pyrolysis

    Directory of Open Access Journals (Sweden)

    Sachin Kumar

    2011-12-01

    Full Text Available Thermal degradation of waste plastics in an inert atmosphere has been regarded as a productive method, because this process can convert waste plastics into hydrocarbons that can be used either as fuels or as a source of chemicals. In this work, waste high-density polyethylene (HDPE plastic was chosen as the material for pyrolysis. A simple pyrolysis reactor system has been used to pyrolyse waste HDPE with the objective of optimizing the liquid product yield at a temperature range of 400ºC to 550ºC. Results of pyrolysis experiments showed that, at a temperature of 450ºC and below, the major product of the pyrolysis was oily liquid which became a viscous liquid or waxy solid at temperatures above 475ºC. The yield of the liquid fraction obtained increased with the residence time for waste HDPE. The liquid fractions obtained were analyzed for composition using FTIR and GC-MS. The physical properties of the pyrolytic oil show the presence of a mixture of different fuel fractions such as gasoline, kerosene and diesel in the oil.

  12. Catalytic fast pyrolysis of lignocellulosic biomass

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Changjun; Wang, Huamin; Karim, Ayman M.; Sun, Junming; Wang, Yong

    2014-11-21

    Increasing energy demand, especially in the transportation sector, and soaring CO2 emissions necessitate the exploitation of renewable sources of energy. Despite the large variety of new energy Q3 carriers, liquid hydrocarbon still appears to be the most attractive and feasible form of transportation fuel taking into account the energy density, stability and existing infrastructure. Biomass is an abundant, renewable source of energy; however, utilizing it in a cost-effective way is still a substantial challenge. Lignocellulose is composed of three major biopolymers, namely cellulose, hemicellulose and lignin. Fast pyrolysis of biomass is recognized as an efficient and feasible process to selectively convert lignocellulose into a liquid fuel—bio-oil. However bio-oil from fast pyrolysis contains a large amount of oxygen, distributed in hundreds of oxygenates. These oxygenates are the cause of many negative properties, such as low heating values, high corrosiveness, high viscosity, and instability; they also greatly Q4 limit the application of bio-oil particularly as transportation fuel. Hydrocarbons derived from biomass are most attractive because of their high energy density and compatibility with the existing infrastructure. Thus, converting lignocellulose into transportation fuels via catalytic fast pyrolysis has attracted much attention. Many studies related to catalytic fast pyrolysis of biomass have been published. The main challenge of this process is the development of active and stable catalysts that can deal with a large variety of decomposition intermediates from lignocellulose. This review starts with the current understanding of the chemistry in fast pyrolysis of lignocellulose and focuses on the development of catalysts in catalytic fast pyrolysis. Recent progress in the experimental studies on catalytic fast pyrolysis of biomass is also summarized with the emphasis on bio-oil yields and quality.

  13. Catalytic fast pyrolysis of lignocellulosic biomass.

    Science.gov (United States)

    Liu, Changjun; Wang, Huamin; Karim, Ayman M; Sun, Junming; Wang, Yong

    2014-11-21

    Increasing energy demand, especially in the transportation sector, and soaring CO2 emissions necessitate the exploitation of renewable sources of energy. Despite the large variety of new energy carriers, liquid hydrocarbon still appears to be the most attractive and feasible form of transportation fuel taking into account the energy density, stability and existing infrastructure. Biomass is an abundant, renewable source of energy; however, utilizing it in a cost-effective way is still a substantial challenge. Lignocellulose is composed of three major biopolymers, namely cellulose, hemicellulose and lignin. Fast pyrolysis of biomass is recognized as an efficient and feasible process to selectively convert lignocellulose into a liquid fuel-bio-oil. However bio-oil from fast pyrolysis contains a large amount of oxygen, distributed in hundreds of oxygenates. These oxygenates are the cause of many negative properties, such as low heating value, high corrosiveness, high viscosity, and instability; they also greatly limit the application of bio-oil particularly as transportation fuel. Hydrocarbons derived from biomass are most attractive because of their high energy density and compatibility with the existing infrastructure. Thus, converting lignocellulose into transportation fuels via catalytic fast pyrolysis has attracted much attention. Many studies related to catalytic fast pyrolysis of biomass have been published. The main challenge of this process is the development of active and stable catalysts that can deal with a large variety of decomposition intermediates from lignocellulose. This review starts with the current understanding of the chemistry in fast pyrolysis of lignocellulose and focuses on the development of catalysts in catalytic fast pyrolysis. Recent progress in the experimental studies on catalytic fast pyrolysis of biomass is also summarized with the emphasis on bio-oil yields and quality. PMID:24801125

  14. Selective and Efficient Deoxygenation of Amine-N-Oxides with CeCl3·7H2O/Zinc System

    International Nuclear Information System (INIS)

    A number of methods have been developed for the deoxygenation of amine-N-oxides, including agents such as low-valent titanium, Zn/HCOONH4, InCl3, tributyltin hydride, Pd/C, tetrathiomolybdate, SmI2, indium/NH4Cl, and Mo(CO)6, Cu(I)-Zn or Cu(I)-Al,11 RuCl3·xH2O, Zn/Cu-triflates. In conclusion, we have discovered that CeCl3·7H2O/Zn system mediates a selective and efficient deoxygenation of amine-N-oxides to the corresponding amines. Although the scope and limitations have not been fully established, the present procedure offers an attractive alternative to the conventional methods with its mildness and chemoselectivity as well as high yields. Further investigations of more useful applications with this system are currently in progress

  15. Pyrolysis/oxidation of low- and medium-level radioactive wastes as pre-treatment for glass-making

    International Nuclear Information System (INIS)

    Pyrolysis, oxidation and glass-making test (cold test) were carried out to examine the possibility of vitrification of low- and medium-level radioactive wastes such as combustible DAW (protection clothes and vinyl sheet) and ion exchange resins, which were pyrolyzed at the temperature of 400?1100 degree C. Pyrolysis/oxidation ash and glass formers were fed into the melting cavity, converted to molten glassy mixture, and poured into a canister. Compressive strength tests were conducted to simply examine the mechanical property of the vitrified product. The optimal pyrolysis temperature ranged from 400 degree C to 600 degree C. At higher temperature, the remaining material after pyrolysis/oxidation was coarse and partially solidified like graphite. Partial solidification of pyrolysis/oxidation ash resulted in heterogeneous glass matrix which could cause mechanical weakness of the glassy waste form. At lower temperature, the remaining material was a very fine material and showed good miscibility with glass formers, which resulted in good mechanical property of the vitrified waste form. In case of protection clothes, vinyl sheet, and spent resin the compressive strength was rapidly decreased up to 5 or 6 times lower than that of neat glass at the 25% of waste content in the vitrified form

  16. The effect of deoxygenation on whole-cell conductance of red blood cells from healthy individuals and patients with sickle cell disease

    OpenAIRE

    Browning, Joseph A.; Staines, Henry M.; Robinson, Hannah C.; Powell, Trevor; Ellory, J Clive; Gibson, John S.

    2007-01-01

    Red blood cells from patients with sickle cell disease (SCD) exhibit increased electrogenic cation permeability, particularly following deoxygenation and hemoglobin (Hb) polymerisation. This cation permeability, termed Psickle, contributes to cellular dehydration and sickling, and its inhibition remains a major goal for SCD treatment. Nevertheless, its characteristics remain poorly defined, its molecular identity is unknown, and effective inhibitors have not been established. Here, patch-clam...

  17. Plasma Pyrolysis Assembly Regeneration Evaluation

    Science.gov (United States)

    Medlen, Amber; Abney, Morgan B.; Miller, Lee A.

    2011-01-01

    In April 2010 the Carbon Dioxide Reduction Assembly (CRA) was delivered to the International Space Station (ISS). This technology requires hydrogen to recover oxygen from carbon dioxide. This results in the production of water and methane. Water is electrolyzed to provide oxygen to the crew. Methane is vented to space resulting in a loss of valuable hydrogen and unreduced carbon dioxide. This is not critical for ISS because of the water resupply from Earth. However, in order to have enough oxygen for long-term missions, it will be necessary to recover the hydrogen to maximize oxygen recovery. Thus, the Plasma Pyrolysis Assembly (PPA) was designed to recover hydrogen from methane. During operation, the PPA produces small amounts of carbon that can ultimately reduce performance by forming on the walls and windows of the reactor chamber. The carbon must be removed, although mechanical methods are highly inefficient, thus chemical methods are of greater interest. The purpose of this effort was to determine the feasibility of chemically removing the carbon from the walls and windows of a PPA reactor using a pure carbon dioxide stream.

  18. Characterization of pyrolytic oil obtained from pyrolysis of TDF (Tire Derived Fuel)

    International Nuclear Information System (INIS)

    Highlights: ? We pyrolyzed Tire Derived Fuel (TDF) at different heating rates and temperatures. ? We determine convenient pyrolysis temperature for pyrolytic oil. ? The product can be used as fuel for combustion system in industry. ? TDF pyrolysis is advisable recycling system because of low hazardous constituents. - Abstract: In recent years, waste utilization before disposing to the land is the most important point about waste management. Due to the increasing emphasis on recycling, related to the two European Commission Directives (EC End of Life Vehicle Directive, EC Waste Landfill Directive) affecting the management of waste tires, there is interest in the development of alternative technologies for recycling waste tires. One of them is pyrolysis. For this purpose, a fixed bed reactor was used to pyrolysis of Tire Derived Fuel (TDF) at the temperatures of 350, 400, 450, 500, 550 and 600 °C with the heating rates of 5 and 35 °C/min. The maximum pyrolytic oil yield (38.8 wt.%) was obtained at 400 °C with 5 °C/min heating rate. The yield of pyrolytic oil decreased with increasing pyrolysis temperatures whereas the yield of gases increased. The fuel properties of the pyrolytic oil including higher heating value (HHV), elemental composition, flash point, viscosity, distillation and density were determined. Pyrolytic oil was characterized by fourier transform infrared spectroscopy (FT-IR), hydrogen nuclear magnetic resonance spectroscopy (1H NMR)ectroscopy (1H NMR) and gas chromatography–mass spectroscopy (GC–MS) techniques and also, the amount of polychlorinated dibenzodioxins/polychlorinated dibenzofurans (PCDDs/PCDFs) and congener distribution characteristics were studied for determination of environmental effects. It was seen that the pyrolytic oils have similar fuel properties with the diesel. It was also found that pyrolytic oil contained 0.00118 I-TEQs/g at very low level. Finally, the pyrolytic oil can be evaluated for energy recovery according to Regulation on Control of Waste Oils in Turkey.

  19. Exhaust constituent emission factors of printed circuit board pyrolysis processes and its exhaust control

    Energy Technology Data Exchange (ETDEWEB)

    Chiang, Hung-Lung, E-mail: hlchiang@mail.cmu.edu.tw [Department of Health Risk Management, China Medical University, Taichung, Taiwan (China); Lin, Kuo-Hsiung [Department of Environmental Engineering and Science, Fooyin University, Kaohsiung, Taiwan (China)

    2014-01-15

    Highlights: • Recycling of waste printed circuit boards is an important issue. • Pyrolysis is an emerging technology for PCB treatment. • Emission factors of VOCs are determined for PCB pyrolysis exhaust. • Iron-Al{sub 2}O{sub 3} catalyst was employed for the exhaust control. -- Abstract: The printed circuit board (PCB) is an important part of electrical and electronic equipment, and its disposal and the recovery of useful materials from waste PCBs (WPCBs) are key issues for waste electrical and electronic equipment. Waste PCB compositions and their pyrolysis characteristics were analyzed in this study. In addition, the volatile organic compound (VOC) exhaust was controlled by an iron-impregnated alumina oxide catalyst. Results indicated that carbon and oxygen were the dominant components (hundreds mg/g) of the raw materials, and other elements such as nitrogen, bromine, and copper were several decades mg/g. Exhaust constituents of CO, H{sub 2}, CH{sub 4}, CO{sub 2}, and NOx, were 60–115, 0.4–4.0, 1.1–10, 30–95, and 0–0.7 mg/g, corresponding to temperatures ranging from 200 to 500 °C. When the pyrolysis temperature was lower than 300 °C, aromatics and paraffins were the major species, contributing 90% of ozone precursor VOCs, and an increase in the pyrolysis temperature corresponded to a decrease in the fraction of aromatic emission factors. Methanol, ethylacetate, acetone, dichloromethane, tetrachloromethane and acrylonitrile were the main species of oxygenated and chlorinated VOCs. The emission factors of some brominated compounds, i.e., bromoform, bromophenol, and dibromophenol, were higher at temperatures over 400 °C. When VOC exhaust was flowed through the bed of Fe-impregnated Al{sub 2}O{sub 3}, the emission of ozone precursor VOCs could be reduced by 70–80%.

  20. Photocatalytic Desulfurization of Waste Tire Pyrolysis Oil

    Directory of Open Access Journals (Sweden)

    Napida Hinchiranan

    2011-11-01

    Full Text Available Waste tire pyrolysis oil has high potential to replace conventional fossil liquid fuels due to its high calorific heating value. However, the large amounts of sulfurous compounds in this oil hinders its application. Thus, the aim of this research was to investigate the possibility to apply the photo-assisted oxidation catalyzed by titanium dioxide (TiO2, Degussa P-25 to partially remove sulfurous compounds in the waste tire pyrolysis oil under milder reaction conditions without hydrogen consumption. A waste tire pyrolysis oil with 0.84% (w/w of sulfurous content containing suspended TiO2 was irradiated by using a high-pressure mercury lamp for 7 h. The oxidized sulfur compounds were then migrated into the solvent-extraction phase. A maximum % sulfur removal of 43.6% was achieved when 7 g/L of TiO2 was loaded into a 1/4 (v/v mixture of pyrolysis waste tire oil/acetonitrile at 50 °C in the presence of air. Chromatographic analysis confirmed that the photo-oxidized sulfurous compounds presented in the waste tire pyrolysis oil had higher polarity, which were readily dissolved and separated in distilled water. The properties of the photoxidized product were also reported and compared to those of crude oil.

  1. Synthesis of Ruthenium Carbonyl Complexes with Phosphine or Substituted Cp Ligands, and Their Activity in the Catalytic Deoxygenation of 1,2-Propanediol

    International Nuclear Information System (INIS)

    A ruthenium hydride with a bulky tetra-substituted Cp ligand, (CpiPr4)Ru(CO)2H (CpiPr4 = C5(i-C3H7)4H) was prepared from the reaction of Ru3(CO)12 with 1,2,3,4-tetraisopropylcyclopentadiene. The molecular structure of (CpiPr4)Ru(CO)2H was determined by X-ray crystallography. The ruthenium hydride complex (C5Bz5)Ru(CO)2H (Bz = CH2Ph) was similarly prepared. The Ru-Ru bonded dimer, ((1,2,3-trimethylindenyl)Ru(CO)2)2, was produced from the reaction of 1,2,3-trimethylindene with Ru3(CO)12, and protonation of this dimer with HOTf gives {((1,2,3-trimethylindenyl)Ru(CO)2)2-(?-H)}+OTf-. A series of ruthenium hydride complexes CpRu(CO)(L)H (L = P(OPh)3, PCy3, PMe3, P(p-C6H4F)3) were prepared by reaction of Cp(CO)2RuH with added L. Protonation of (CpiPr4)Ru(CO)2H, Cp*Ru(CO)2H, or CpRu(CO)(P-(OPh)3)H by HOTf at -80 C led to equilibria with the cationic dihydrogen complexes, but H2 was released at higher temperatures. Protonation of CpRu(P(OPh)3)2H with HOTf gave an observable dihydrogen complex, {CpRu(P-(OPh)3)2( {CpRu(P-(OPh)3)2(?2-H2)}+OTf- that was converted at -20 C to the dihydride complex {CpRu(P(OPh)3)2(H)2}+OTf-. These Ru complexes serve as catalyst precursors for the catalytic deoxygenation of 1,2-propanediol to give n-propanol. The catalytic reactions were carried out in sulfolane solvent with added HOTf under H2 (750 psi) at 110 C.

  2. Modeling Initial Stage of Ablation Material Pyrolysis: Graphitic Precursor Formation and Interfacial Effects

    Science.gov (United States)

    Desai, Tapan G.; Lawson, John W.; Keblinski, Pawel

    2010-01-01

    Reactive molecular dynamics simulations are used to study initial stage of pyrolysis of ablation materials and their composites with carbon nanotubes and carbon fibers. The products formed during pyrolysis are characterized and water is found as the primary product in all cases. The water formation mechanisms are analyzed and the value of the activation energy for water formation is estimated. A detailed study on graphitic precursor formation reveals the presence of two temperature zones. In the lower temperature zone (less than 2000 K) polymerization occurs resulting in formation of large, stable graphitic precursors, and in the high temperature zone (greater than 2000 K) polymer scission results in formation of short polymer chains/molecules. Simulations performed in the high temperature zone on the phenolic resin composites (with carbon nanotubes and carbon fibers) shows that the presence of interfaces had no substantial effect on the chain scission rate or the activation energy value for water formation.

  3. Passivation of carbon steel alloy in de-oxygenated alkaline pH media. The effect of various additives

    International Nuclear Information System (INIS)

    The ability of certain additives to influence the oxide film formation characteristics on carbon steel alloy under de-oxygenated alkaline pH conditions at 473 K has been investigated. The additives used in the study are: boric acid, glucose, hydrazine, morpholine and cyclohexylamine. Their relative impacts on the passivation processes are evaluated by using the data on base metal loss, soluble and insoluble iron released to the medium and scanning electron microscopic studies of the topography of the coating and electrochemical investigations on the protectivity of the oxide coating. These results have been compared with the passivation behaviour of this alloy obtained under simple alkaline pH treatment with LiOH without any additive. The effectiveness of the passivation treatment is found to be greatly enhanced in the presence of boric acid and hydrazine. Based on the effectiveness in inducing passivity to a carbon steel surface, the additives can be arranged in the following order: boric acid ? hydrazine > cyclohexylamine > morpholine > LiOH(blank) > glucose. (author)

  4. Paradoxical correlation between signal in functional magnetic resonance imaging and deoxygenated haemoglobin content in capillaries: a new theoretical explanation

    International Nuclear Information System (INIS)

    Signal increases in functional magnetic resonance imaging (fMRI) are believed to be a result of decreased paramagnetic deoxygenated haemoglobin (deoxyHb) content in the neural activation area. However, discrepancies in this canonical blood oxygenation level dependent (BOLD) theory have been pointed out in studies using optical techniques, which directly measure haemoglobin changes. To explain the discrepancies, we developed a new theory bridging magnetic resonance (MR) signal and haemoglobin changes. We focused on capillary influences, which have been neglected in most previous fMRI studies and performed a combined fMRI and near-infrared spectroscopy (NIRS) study using a language task. Paradoxically, both the MR signal and deoxyHb content increased in Broca's area. On the other hand, fMRI activation in the auditory area near large veins correlated with a mirror-image decrease in deoxyHb and increase in oxygenated haemoglobin (oxyHb), in agreement with canonical BOLD theory. All fMRI signal changes correlated consistently with changes in oxyHb, the diamagnetism of which is insensitive to MR. We concluded that the discrepancy with the canonical BOLD theory is caused by the fact that the BOLD theory ignores the effect of the capillaries. Our theory explains the paradoxical phenomena of the oxyHb and deoxyHb contributions to the MR signal and gives a new insight into the precise haemodynamics of activation by analysing fMRI and NIRS data. (author)RS data. (author)

  5. Changes in whole tissue heme concentration dissociates muscle deoxygenation from muscle oxygen extraction during passive head-up tilt.

    Science.gov (United States)

    Adami, Alessandra; Koga, Shunsaku; Kondo, Narihiko; Cannon, Daniel T; Kowalchuk, John M; Amano, Tatsuro; Rossiter, Harry B

    2015-05-01

    Skeletal muscle deoxygenated hemoglobin and myoglobin concentration ([HHb]), assessed by near-infrared spectroscopy (NIRS), is commonly used as a surrogate of regional O2 extraction (reflecting the O2 delivery-to-consumption ratio, Q?/V?o2). However, [HHb] change (?[HHb]) is also influenced by capillary-venous heme concentration, and/or small blood vessel volume (reflected in total heme; [THb]). We tested the hypotheses that ?[HHb] is associated with O2 extraction, and insensitive to [THb], over a wide range of Q?/V?o2 elicited by passive head-up tilt (HUT; 10-min, 15° increments, between -10° and 75°). Steady-state common femoral artery blood flow (FBF) was measured by echo-Doppler, and time-resolved NIRS measured [HHb] and [THb] of vastus lateralis (VL) and gastrocnemius (GS) in 13 men. EMG confirmed muscles were inactive. During HUT in VL [HHb] increased linearly (57 ± 10 to 101 ± 16 ?M; P knowledge of tissue O2 saturation nor vascular compliance could appropriately account for the ?[HHb]-?FBF dissociation. Thus, under passive tilt, [HHb] is influenced by Q?/V?o2, as well as microvascular hematocrit and/or tissue blood vessel volume, complicating its use as a noninvasive surrogate for muscle microvascular O2 extraction. PMID:25678700

  6. Nanocrystalline SnO2 by liquid pyrolysis

    Directory of Open Access Journals (Sweden)

    Morante, J. R.

    2000-08-01

    Full Text Available Liquid pyrolysis is presented as a new production method of SnO2 nanocrystalline powders suitable for gas sensor devices. The method is based on a pyrolytic reaction of high tensioned stressed drops of an organic solution of SnCl4•5(H2O. The main advantages of the method are its capability to produce SnO2 nanopowders with high stability, its accurate control over the grain size and other structural characteristics, its high level of repeatability and its low industrialization implementation cost. The characterization of samples of SnO2 nanoparticles obtained by liquid pyrolysis in the range between 200ºC and 900ºC processing temperature is carried out by X-ray diffraction, transmission electron microscopy, Raman and X-ray photoelectron spectroscopy. Results are analyzed and discussed so as to validate the advantages of the liquid pyrolysis method.La pirólisis líquida se presenta como un nuevo método para producir SnO2 nanocristalino en polvo ideal para sensores de gas. El método se basa en una reacción pirolítica de gotas altamente tensionadas procedentes de una solución orgánica de SnCl4•5(H2O. Las principales ventajas del método son la capacidad para producir nanopartículas de SnO2 con una gran estabilidad, el preciso control sobre el tamaño de grano y sobre otras características estructurales, el alto nivel de repetibilidad y el bajo coste en su implementación industrial.La caracterización de las muestras de las nanopartículas de SnO2 obtenidas por pirólisis líquida en un rango de temperatura de procesado que va de 200ºC a 900ºC se ha realizado mediante difracción de rayos X, microscopía electrónica de transmisión, espectroscopía Raman y espectroscopía fotoelectrónica de rayos X. Los resultados se han analizado y discutido. Éstos validan las ventajas del método de la pirólisis líquida.

  7. Characterization of Sr?-alumina prepared by sol-gel and spray pyrolysis methods

    International Nuclear Information System (INIS)

    Eu2+ doped ?-alumina, Sr1-xMgAl10O17 Eux2+ (x=0.01-0.07) were successfully prepared by sol-gel and spray pyrolysis techniques with the same precursor materials. Sr?-alumina doped with Eu2+ (SrMgAl10O17:Eu2+) prepared from sol-gel method showed three photoluminescence (PL) peaks at 390, 418 and 459 nm after excitation wavelength at 254 nm and one PL peak at 461 nm when excitation was at 365 nm. The same powder was prepared from spray pyrolysis technique showed the six PL peaks at 323, 397, 415, 443, 480 and 508 nm after excitation at 254 nm. Also two PL peaks at 440 and 480 nm were observed after the excitation at 365 nm. These PL peaks were dependent on the excitation wavelength. The effect of different annealing temperatures of sol-gel powders, preparation conditions of spray pyrolysis powders and reduction atmospheres of both sol-gel and spray pyrolysis powders of various compositions of Eu2+ doped Sr?-alumina were also studied. Both the powders were characterized by scanning electron microscopy, X-ray diffraction and PL techniques and comparison between the two preparation methods. Sol-gel prepared powder had eight times higher PL intensity and brightness than the spray pyrolysis prepared powder. The suggested good composition of Sr?-alumina is Sr0.93MgAl10O17:Eu0.07 for both sol-gel and spay pyroly/sub> for both sol-gel and spay pyrolysis methods

  8. Liquid oil and residual characteristics of printed circuit board recycle by pyrolysis

    International Nuclear Information System (INIS)

    Highlights: • Pyrolysis is a technology for recycling of the non-metal fraction of PCBs. • Liquid product constituents were analyzed for PCB pyrolysis. • Water-soluble ionic species were determined for PCB pyrolysis exhaust. - Abstract: Non-metal fractions of waste printed circuit boards (PCBs) were thermally treated (200–500 °C) under nitrogen atmosphere. Carbon, hydrogen, and nitrogen were determined by elemental analyzer, bromine by instrumental neutron activation analysis (INAA), phosphorus by energy dispersive X-ray spectrometer (EDX), and 29 trace elements by inductively coupled plasma atomic emission spectrometer (ICP-AES) and mass spectrometry (ICP-MS) for raw material and pyrolysis residues. Organic compositions of liquid oil were identified by GC (gas chromatography)–MS, trace element composition by ICP system, and 12 water-soluble ions by IC (ionic chromatography). Elemental content of carbon was >450 mg/g, oxygen 300 mg/g, bromine and hydrogen 60 mg/g, nitrogen 30 mg/g, and phosphorus 28 mg/g. Sulfur was trace in PCBs. Copper content was 25–28 mg/g, iron 1.3–1.7 mg/g, tin 0.8–1.0 mg/g and magnesium 0.4–1.0 mg/g; those were the main metals in the raw materials and pyrolytic residues. In the liquid products, carbon content was 68–73%, hydrogen was 10–14%, nitrogen was 4–5%, and sulfur was less than 0.05% at pyrolysis temperatures from 300 to 500 °C. Phenol, 3-bromophenol, 2-methylphenol and 4-propan-2-ylphenol were major species in liquid products, accounting for >50% of analyzed organic species. Bromides, ammonium and phosphate were the main species in water sorption samples for PCB pyrolysis exhaust

  9. Liquid oil and residual characteristics of printed circuit board recycle by pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Kuo-Hsiung [Department of Environmental Engineering and Science, Fooyin University, Kaohsiung, Taiwan (China); Chiang, Hung-Lung, E-mail: hlchiang@mail.cmu.edu.tw [Department of Health Risk Management, China Medical University, Taichung, Taiwan (China)

    2014-04-01

    Highlights: • Pyrolysis is a technology for recycling of the non-metal fraction of PCBs. • Liquid product constituents were analyzed for PCB pyrolysis. • Water-soluble ionic species were determined for PCB pyrolysis exhaust. - Abstract: Non-metal fractions of waste printed circuit boards (PCBs) were thermally treated (200–500 °C) under nitrogen atmosphere. Carbon, hydrogen, and nitrogen were determined by elemental analyzer, bromine by instrumental neutron activation analysis (INAA), phosphorus by energy dispersive X-ray spectrometer (EDX), and 29 trace elements by inductively coupled plasma atomic emission spectrometer (ICP-AES) and mass spectrometry (ICP-MS) for raw material and pyrolysis residues. Organic compositions of liquid oil were identified by GC (gas chromatography)–MS, trace element composition by ICP system, and 12 water-soluble ions by IC (ionic chromatography). Elemental content of carbon was >450 mg/g, oxygen 300 mg/g, bromine and hydrogen 60 mg/g, nitrogen 30 mg/g, and phosphorus 28 mg/g. Sulfur was trace in PCBs. Copper content was 25–28 mg/g, iron 1.3–1.7 mg/g, tin 0.8–1.0 mg/g and magnesium 0.4–1.0 mg/g; those were the main metals in the raw materials and pyrolytic residues. In the liquid products, carbon content was 68–73%, hydrogen was 10–14%, nitrogen was 4–5%, and sulfur was less than 0.05% at pyrolysis temperatures from 300 to 500 °C. Phenol, 3-bromophenol, 2-methylphenol and 4-propan-2-ylphenol were major species in liquid products, accounting for >50% of analyzed organic species. Bromides, ammonium and phosphate were the main species in water sorption samples for PCB pyrolysis exhaust.

  10. Structural Properties of Magnesium Oxide Thin Films Deposited by Spray Pyrolysis Technique

    Directory of Open Access Journals (Sweden)

    Dyachenko A.

    2014-08-01

    Full Text Available In this work, structural properties of magnesium oxide films have studied by X-ray diffraction methods. MgO obtained by spray pyrolysis technique at the different substrate temperatures on the glass substrates. The 0.2 M magnesium chloride hexahydrate aqueous solution was selected as a precursor in the solution. The influence of substrate temperature on the phase composition, texture quality, coherent scattering domain size and lattice constant of the material was investigated.

  11. Structural Properties of Magnesium Oxide Thin Films Deposited by Spray Pyrolysis Technique

    OpenAIRE

    Dyachenko A.; Opanasuyk A.; Kurbatov D.; Bolshanina S.; Kuznetsov V

    2014-01-01

    In this work, structural properties of magnesium oxide films have studied by X-ray diffraction methods. MgO obtained by spray pyrolysis technique at the different substrate temperatures on the glass substrates. The 0.2 M magnesium chloride hexahydrate aqueous solution was selected as a precursor in the solution. The influence of substrate temperature on the phase composition, texture quality, coherent scattering domain size and lattice constant of the material was investigated.

  12. Pyrolysis Mechanisms of Aromatic Carboxylic Acids

    Energy Technology Data Exchange (ETDEWEB)

    Britt, P.F.; Eskay, T.P.; Buchanan, A.C. III

    1997-12-31

    Although decarboxylation of carboxylic acids is widely used in organic synthesis, there is limited mechanistic information on the uncatalyzed reaction pathways of aromatic carboxylic acids at 300-400 {degrees} C. The pyrolysis mechanisms of 1,2-(3,3-dicarboxyphenyl)ethane, 1,2-(4,4-dicarboxylphenyl)ethane, 1-(3-carboxyphenyl)-2-(4- biphenyl)ethane, and substituted benzoic acids have been investigated at 325-425 {degrees} C neat and diluted in an inert solvent. Decarboxylation is the dominant pyrolysis path. Arrhenius parameters, substituent effects, and deuterium isotope effects are consistent with decarboxylation by an electrophilic aromatic substitution reaction. Pyrolysis of benzoic acid in naphthalene, as a solvent, produces significant amounts of 1- and 2-phenylnaphthalenes. The mechanistic pathways for decarboxylation and arylation with be presented.

  13. Co pyrolysis of biomass and PP

    International Nuclear Information System (INIS)

    Full text: While bio-oil has received considerable attention both as a source of energy and as an organic feedstock, its stability as fuel is very low due to high oxygen content. Therefore, there are many efforts to upgrade it. Among them, co pyrolysis with polyolefin can be a method to obtain stable bio-oil. Because polyolefins contain higher hydrogen and carbon content than biomass and no oxygen, plastic/ biomass co pyrolysis may upgrade the bio-oil properties by increasing the carbon and hydrogen contents while reducing oxygen content. In this study, wood biomass was mixed with PP and then co pyrolysis was carried out in a batch reactor. The produced oil and gas was analyzed using GC and GC-MS. Also elemental analysis was performed to know the hydrogen, carbon and oxygen content of bio-oil. The effect of various reaction conditions on bio-oil properties were presented in detail. (author)

  14. Characterization of the pyrolysis products of methiopropamine.

    Science.gov (United States)

    Bouso, Emily D; Gardner, Elizabeth A; O'Brien, John E; Talbot, Brian; Kavanagh, Pierce V

    2014-01-01

    1-(Thien-2-yl)-2-methylaminopropane (methiopropamine, MPA), appeared as a 'legal high' in late 2010. It is structurally similar to methamphetamine, with a thiophene ring replacing the benzene moiety. Methiopropamine reportedly retains the pharmacological properties of amphetamine stimulants, but it does not fall under existing drug laws in the USA and Ireland. The objective of this research was to identify the pyrolysis products formed under conditions that mimic those used by recreational drugs users. Thirteen pyrolysis products were identified and ten were confirmed by comparison to synthesized standards. Methods for synthesizing the standards as well as an alternative method for the synthesis of methiopropamine were developed. The MPA pyrolysis products are formed through N-dealkylation, N-alkylation, N-formylation, ?-carbon oxidation, ?-carbon oxidation/N-alkylation, amine elimination and carbon-carbon bond cleavage. Two pyrazine isomers also formed. Some of these products have the potential to be psychoactive while others are potentially toxic. PMID:24166818

  15. Characteristics of palm bark pyrolysis experiment oriented by central composite rotatable design

    International Nuclear Information System (INIS)

    The rotatable design was applied for directing pyrolysis experiment of palm bark with the variation of retention time and reaction temperature. Based on the regression equations, the optimal operating conditions were extrapolated at 13.2 min, 459 °C and 15.7 min, 475 °C. The gas product comprised mainly C1–C4 hydrocarbons with the content up to 58.2 wt% while the liquid product was a complex mixture composed of mostly oxygenated compounds. Owing to using the high pressure condition as in tubing reactor, the reaction characteristics were different from those at normal pressure, thus possibly resulting in the high selectivity for liquid product. The analysis result of solid residue after reaction showed that the oxygen content was decreased noticeably to 25.4 wt% as compared to that of raw biomass due to pyrolysis. - Highlights: • Pyrolysis of palm kernel cake in a tubing reactor. • Apply the central composite rotatable design. • Effect of namely retention time, reaction temperature and mass of sample on product yields. • Analysis of bio-oils from the pyrolysis of palm bark

  16. Characteristics of pyrobitumen and oil obtained from Green River oil shale pyrolysis

    International Nuclear Information System (INIS)

    Pyrobitumens and oils generated from the isothermal pyrolysis of Green River oil shale at 4000, 4250, and 4400C for different times were characterized. Elemental contents, average molecular weights, and hydrocarbon contents were determined for the pyrobitumens and oils. The pyrobitumens, a major initial pyrolysis product, had an average molecular weight exceeding 1200 and contained about 85% polars. The atomic hydrogen-to-carbon ratio, nitrogen content, and average molecular weight of the pyrobitumens changed with pyrolysis temperatures and times. The variable composition of the pyrobitumens suggests that pyrobitumen should not be considered as a single intermediate for kerogen decomposition. In contrast, oils contained 60% hydrocarbons and had a constant atomic hydrogen-to-carbon ratio and average molecular weight of about 250. However, the nitrogen content of the oils increased with increasing reaction time. The ratios of normal heptadecane/pristane and normal octadecane/phytane, and odd-even predominance of oils were sensitive to pyrolysis temperatures and times. The rate constants, frequency factors, and activation energies of the formations of the total hydrocarbons, aliphatic hydrocarbons, and aromatic hydrocarbons of the oils were calculated

  17. Study on delacquer used beverage cans by vacuum pyrolysis for recycle.

    Science.gov (United States)

    Li, Ning; Qiu, Keqiang

    2013-10-15

    So far, conventional processes that have been employed to delacquer the paints decorated on used beverage cans (UBCs) are less than satisfactory in economic and environmental effect. Therefore, a new method combining vacuum pyrolysis with dilute sulfuric acid leaching to delacquer the paints was investigated. The results of vacuum pyrolysis showed that the decoating rate increased with the increase of temperature and the paints were almost 100% removed from UBCs under the following conditions: temperature of 650 °C, holding time of 20 min, and residual gas pressure lower than 0.1 kPa. The pyrolysis oil was mainly composed of phenol and 2-methy-phenol analyzed by GC-MS. The delacquered UBCs were subsequently leached with 5% H2SO4 for 60 s and TiO2 was recovered by calcining the residuals in muffle furnace at 450 °C for 15 min. This innovative technology offers an effective method to delacquer paints from UBCs, which obtains excellent stripping effect and avoids the production of toxic substances generated in direct combustion process. Furthermore, the pyrolysis oil can be reused as chemical feedstock in other fields. PMID:24070094

  18. Comparative analysis of pinewood, peanut shell, and bamboo biomass derived biochars produced via hydrothermal conversion and pyrolysis.

    Science.gov (United States)

    Huff, Matthew D; Kumar, Sandeep; Lee, James W

    2014-12-15

    Biochars were produced from pinewood, peanut shell, and bamboo biomass through hydrothermal conversion (HTC) at 300 °C and comparatively by slow pyrolysis over a temperature range of 300, 400, and 500 °C. These biochars were characterized by FT-IR, cation exchange capacity (CEC) assay, methylene blue adsorption, as well as proximate and elemental analysis. The experimental results demonstrated higher retained oxygen content in biochars produced at lower pyrolysis temperatures and through HTC, which also correlated to the higher CEC of respective biochars. Furthermore, all types of biochar studied herein were capable of adsorption of methylene blue from solution and the adsorption did not appear to strongly correlate with CEC, indicating that the methylene blue adsorption appears to be dependent more upon the non-electrostatic molecular interactions such as the likely dispersive ?-? interactions between the graphene-like sheets of the biochar with the aromatic ring structure of the dye, than the electrostatic CEC. A direct comparison of hydrothermal and pyrolysis converted biochars reveals that biochars produced through HTC have much higher CEC than the biochars produced by slow pyrolysis. Analysis by FT-IR reveals a higher retention of oxygen functional groups in HTC biochars; additionally, there is an apparent trend of increasing aromaticity of the pyrolysis biochars when produced at higher temperatures. The CEC value of the HTC biochar appears correlated with its oxygen functional group content as indicated by the FT-IR measurements and its O:C ratio. PMID:25190598

  19. Pyrolysis of Pinus pinaster in a two-stage gasifier: Influence of processing parameters and thermal cracking of tar

    Energy Technology Data Exchange (ETDEWEB)

    Fassinou, Wanignon Ferdinand; Toure, Siaka [Laboratoire d' Energie Solaire-UFR-S.S.M.T. Universite de Cocody, 22BP582 Abidjan 22 (Ivory Coast); Van de Steene, Laurent; Volle, Ghislaine; Girard, Philippe [CIRAD-Foret, TA 10/16, 73, avenue J.-F. Breton, 34398 Montpellier, Cedex 5 (France)

    2009-01-15

    A new two-stage gasifier with fixed-bed has recently been installed on CIRAD facilities in Montpellier. The pyrolysis and the gasifier units are removable. In order to characterise the pyrolysis products before their gasification, experiments were carried out, for the first time only with the pyrolysis unit and this paper deals with the results obtained. The biomass used is Pinus pinaster. The parameters investigated are: temperature, residence time and biomass flow rate. It has been found that increasing temperature and residence time improve the cracking of tars, gas production and char quality (fixed carbon rate more than 90%, volatile matter rate less than 4%). The increase of biomass flow rate leads to a bad char quality. The efficiency of tar cracking, the quality and the heating value of the charcoal and the gases, indicate that: temperature between 650 C and 750 C, residence time of 30 min, biomass flow rate between 10 and 15 kg/h should be the most convenient experimental conditions to get better results from the experimental device and from the biomass pyrolysis process. The kinetic study of charcoal generation shows that the pyrolysis process, in experimental conditions, is a first-order reaction. The kinetic parameters calculated are comparable with those found by other researchers. (author)

  20. Pyrolysis Pathways of Sulfonated Polyethylene, an Alternative Carbon Fiber Precursor

    Energy Technology Data Exchange (ETDEWEB)

    Younker, Jarod M [ORNL; Saito, Tomonori [ORNL; Hunt, Marcus A [ORNL; Beste, Ariana [ORNL; Naskar, Amit K [ORNL

    2013-01-01

    Sulfonated polyethylene is an emerging precursor for the production of carbon fibers. Pyrolysis of sulfonated polyethylene was characterized by thermogravimetric analysis (TGA). n-heptane-4-sulfonic acid (H4S) was selected as a model compound for the study of sulfonated polyethylene. Density functional theory and conventional transition state theory were used to determine the rate constants of pyrolysis for H4S from 300-1000 K. Multiple reaction channels from two different mechanisms were explored: 1) internal five-centered elimination (Ei 5) and 2) radical chain reaction. The pyrolysis of H4S was simulated with kinetic Monte Carlo (kMC) to obtain TGA plots that compared favorably to experiment. We observed that at tem- peratures < 550 K, the radical mechanism was dominant and yielded the trans-alkene, whereas cis-alkene was formed at higher temperatures from the internal elimination. The maximum rates of % mass loss became independent of initial OH radical concentration at 440-480 K. Experimentally, the maximum % mass loss occurred from 440-460 K (heating rate dependent). Activation energies derived from the kMC-simulated TGAs of H4S (26-29 kcal/mol) agreed with experiment for sulfonated polyethylene ( 31 kcal/mol). The simulations revealed that in this region, decomposition of radical HOSO2 became competitive to H abstraction by HOSO2, making OH the carrying radical for the reaction chain. The maximum rate of % mass loss for internal elimination was observed at temperatures > 600 K. Low-scale carbonization utilizes temperatures < 620 K; thus, internal elimination will not be competitive. Ei5 elimination has been studied for sulfoxides and sulfones, but this represents the first study of internal elimination in sulfonic acids. Nonlinear Arrhenius plots were found for all bimolecular reactions. The most significant nonlinear behavior was observed for reactions where the barrier was small. For reactions with low activation barriers, nonlinearity was traced to conflicting trends between the exponential temperature dependence of the energetic term and the temperature dependence of the vibrational partition function of the transitional modes.

  1. Mixtures of rubber tyre and plastic wastes pyrolysis: A kinetic study

    International Nuclear Information System (INIS)

    The study performed aimed at analysing possible routes for pyrolysis reaction mechanisms of polymeric materials namely RT (rubber tyre) and plastic wastes (PE (polyethylene), PP (polypropylene) and PS (polystyrene)). Consequently, and seeking sustainable transformation of waste streams into valuable chemicals and renewable liquid fuels, mixture of 30% RT, 20% PE, 30% PP and 20% PS was subjected to pyrolysis. Different kinetic models were studied using experimental data. None of the mechanisms found in literature led to a numerical adjustment and different pathways were investigated. Kinetic studies were performed aiming to evaluate direct conversions into new solid, liquid and gaseous products and if parallel reactions and/or reversible elementary steps should be included. Experiments were performed in batch system at different temperatures and reaction times. Kinetic models were evaluated and reaction pathways were proposed. Models reasonably fit experimental data, allow explaining wastes thermal degradation. Kinetic parameters were estimated for all temperatures and dependence of Ea and pre-exponential factor on temperature was evaluated. The rate constant of some reactions exhibited nonlinear temperature dependence on the logarithmic form of Arrhenius law. This fact strongly suggests that temperature has a significant effect on reaction mechanism of pyrolysis of mixtures of rubber tyre and plastic wastes. - Highlights: • Kinetic study of rubber tyre (RT) and different plastic wastes (PE, PP and PS) was performed in batch reactor. • Definition of possible pathways taken into account for the formation of final products. • Kinetic parameters were estimated. • The effect of reaction temperature and reaction time on liquid composition was performed

  2. Toxicity of pyrolysis gases from polytetrafluoroethylene

    Science.gov (United States)

    Hilado, C. J.; Schneider, J. E.

    1979-01-01

    A sample of polytetrafluoroethylene was evaluated for toxicity of pyrolysis gases, using various test conditions of the toxicity screening test method developed at the University of San Francisco. Time to death appears to be affected by the material of which the pyrolysis tube is made, with Monel tending to give longer times to death than quartz. When quartz tubes are used, time to death seems to be related to carbon monoxide concentration. When Monel tubes are used, carbon monoxide does not appear to be the principal toxicant.

  3. Investigating the potential for energy, fuel, materials and chemicals production from corn residues (cobs and stalks) by non-catalytic and catalytic pyrolysis in two reactor configurations

    Energy Technology Data Exchange (ETDEWEB)

    Ioannidou, O.; Zabaniotou, A. [Chemical Engineering Department, Aristotle University of Thessaloniki, Thessaloniki (Greece); Antonakou, E.V.; Papazisi, K.M.; Lappas, A.A. [Chemical Process Engineering Research Institute (CPERI) (Greece); Athanassiou, C. [Department of Engineering and Management of Energy Resources, University of Western Macedonia (Greece)

    2009-05-15

    The results of thermogravimetric analysis (TGA), non-catalytic and catalytic pyrolysis of corn cobs and corn stalks are reported in this paper. Pyrolysis took place in two different reactor configurations for both feedstocks: (1) fast pyrolysis in a captive sample reactor; and (2) non-catalytic slow pyrolysis and catalytic pyrolysis in a fixed-bed reactor. Experiments were carried out in atmospheric pressure at three temperatures: low temperature (360-380 C), medium temperature (500-600 C) and at high temperature (600-700 C). The results of the experimental study were compared with data reported in the literature. Investigating the potential of corn residues for energy, fuel, materials and chemicals production according to their thermochemical treatment products yields and quality, it can be stated that: (a) corn stalks could be suitable raw material for energy production via gasification at high temperature, due to their medium low heating value (LHV) of pyrolysis gas (13-15 MJ/m{sup 3}); (b) corn cob could be a good solid biofuel, due to the high LHV (24-26 MJ/kg) of the produced char; (c) additionally, corn cobs could be a good material for activated carbon production after being activated or gasified with steam, due to its high fixed carbon content({proportional_to}74 wt%); (d) liquid was the major pyrolysis product from catalytic pyrolysis (about 40-44 wt% on biomass) for both feedstocks; further analysis of the organic phase of the liquid products were hydrocarbons and phenols, which make them interesting for chemicals production. (author)

  4. Novel sorbent materials for environmental remediation via Pyrolysis of biomass

    Science.gov (United States)

    Zabaniotou, Anastasia

    2013-04-01

    One of the major challenges facing society at this moment is the transition from a non-sustainable, fossil resources-based economy to a sustainable bio-based economy. By producing multiple products, a biorefinery can take advantage of the differences in biomass components and intermediates and maximize the value derived from the biomass feedstock. The high-value products enhance profitability, the high-volume fuel helps meet national energy needs, and the power production reduces costs and avoids greenhouse-gas emissions From pyrolysis, besides gas and liquid products a solid product - char, is derived as well. This char contains the non converted carbon and can be used for activated carbon production and/or as additive in composite material production. Commercially available activated carbons are still considered expensive due to the use of non-renewable and relatively expensive starting material such as coal. The present study describes pyrolysis as a method to produce high added value carbon materials such as activated carbons (AC) from agricultural residues pyrolysis. Olive kernel has been investigated as the precursor of the above materials. The produced activated carbon was characterized by proximate and ultimate analyses, BET method and porosity estimation. Furthermore, its adsorption of pesticide compound in aqueous solution by was studied. Pyrolysis of olive kernel was conducted at 800 oC for 45min in a fixed reactor. For the production of the activated carbon the pyrolytic char was physically activated under steam in the presence of CO2 at 970oC for 3 h in a bench scale reactor. The active carbons obtained from both scales were characterized by N2 adsorption at 77 K, methyl-blue adsorption (MB adsorption) at room temperature and SEM analysis. Surface area and MB adsorption were found to increase with the degree of burn-off. The surface area of the activated carbons was found to increase up to 1500 m2/g at a burn-off level of 60-65wt.%, while SEM analysis showed the appearance of micropores to mesopores in the produced tire active carbons. Activated carbon prepared from olive kernel is a super active carbon and used as an adsorbent for the removal of pesticide from aqueous solutions (Bromopropylate). The higher removal achieved was 100% in 60 min. The produced activated carbon from agricultural residue was proved to be very effective for gas and water stream purification. Biomass can give a wide spectrum of fuels and materials in the integrated concept of biorefinery

  5. Processes for converting lignocellulosics to reduced acid pyrolysis oil

    Energy Technology Data Exchange (ETDEWEB)

    Kocal, Joseph Anthony; Brandvold, Timothy A

    2015-01-06

    Processes for producing reduced acid lignocellulosic-derived pyrolysis oil are provided. In a process, lignocellulosic material is fed to a heating zone. A basic solid catalyst is delivered to the heating zone. The lignocellulosic material is pyrolyzed in the presence of the basic solid catalyst in the heating zone to create pyrolysis gases. The oxygen in the pyrolysis gases is catalytically converted to separable species in the heating zone. The pyrolysis gases are removed from the heating zone and are liquefied to form the reduced acid lignocellulosic-derived pyrolysis oil.

  6. Characterization of corncob-derived biochar and pyrolysis kinetics in comparison with corn stalk and sawdust.

    Science.gov (United States)

    Liu, Xuan; Zhang, Yang; Li, Zifu; Feng, Rui; Zhang, Yaozhong

    2014-10-01

    In this study, thermal and physicochemical characterization results of corncob (CC) and its derived biochars were analyzed and differentiated from sawdust (SD) and cornstalk (CS). The pyrolysis temperature shows the largest effect on the yield of biochar produced compare with residing time, heating rate, and feedstock particle size. The CC-derived biochars produced at temperatures ranging from 300 to 600°C were analyzed. The CC was thermochemically altered to a stable biochar when the pyrolysis temperature was set to over 500°C. To deduce the reaction mechanism of the CC during the major thermal decomposition stage, 16 mechanisms in solid-state reactions were applied. The reaction order and nucleation mechanisms described the thermal decomposition of the CC. By using the best-fitted mechanisms, the kinetic parameters were calculated. The weight active energy of the CC was 122.42kJ/mol, which was the lowest value compared to those of CS and SD. PMID:25125195

  7. Bio-methane via fast pyrolysis of biomass

    International Nuclear Information System (INIS)

    Highlights: ? Pyrolysis gases can efficiently be upgraded to bio-methane. ? The integration can increase energy efficiency and provide a renewable vehicle fuel. ? The biomass to bio-methane conversion efficiency is 83% (HHV). ? The efficiency is higher compared to bio-methane produced via gasification. ? Competitive alternative to other alternatives of bio-oil upgrading. - Abstract: Bio-methane, a renewable vehicle fuel, is today produced by anaerobic digestion and a 2nd generation production route via gasification is under development. This paper proposes a poly-generation plant that produces bio-methane, bio-char and heat via fast pyrolysis of biomass. The energy and material flows for the fuel synthesis are calculated by process simulation in Aspen Plus®. The production of bio-methane and bio-char amounts to 15.5 MW and 3.7 MW, when the total inputs are 23 MW raw biomass and 1.39 MW electricity respectively (HHV basis). The results indicate an overall efficiency of 84% including high-temperature heat and the biomass to bio-methane yield amounts to 83% after allocation of the biomass input to the final products (HHV basis). The overall energy efficiency is higher for the suggested plant than for the gasification production route and is therefore a competitive route for bio-methane production

  8. Pyrolysis of drugs of abuse: a comprehensive review.

    Science.gov (United States)

    Bell, Suzanne; Nida, Corey

    2015-06-01

    This review summarizes the literature to date relating to pyrolysis and heated vapour ingestion of drugs of abuse. In this context, heating is referred to as smoking or pyrolysis, but these are generic descriptors that encompass numerous methods of vapour generation and inhalation. Depending on the amount of drug used, diluents and contaminants present, heating conditions, and the oxidative/reductive environment, many thermal decomposition products can be formed. In addition to the recognized hazard of rapid onset of pharmacological effects of the parent drug, thermal decomposition products may be pharmacologically active as well as acutely/chronically toxic. For example, several published reports have linked heroin smoking to a form of brain encephalopathy and to the development of movement disorders. Early qualitative studies focusing on the thermal decomposition of drugs have evolved into more complex investigations employing mass spectral identification, confirmation, and elucidation of formation mechanism. In most cases, thermal decomposition begins with cleavage of the weakest bond (often C-N) to generate free radicals that then form the most stable sterically favoured products. Several reports of rearrangements at higher temperatures have been identified and hint at an underlying complexity that arises from the variety of smoking methods and conditions. Given that many designer drugs such as synthetic cannabinoids are ingested primarily through smoking, this issue has taken on new importance. Copyright © 2015 John Wiley & Sons, Ltd. PMID:25865019

  9. Influence of Partial Combustion on Rapid Pyrolysis of Wood Biomass

    Science.gov (United States)

    Yasuda, Hajime; Yamada, Osamu; Kaiho, Mamoru; Shinagawa, Takuya; Matsui, Satoshi; Iwasaki, Toshihiko; Shimada, Sohei

    A batch reactor was made and used in this work. In an actual rapid pyrolyzer/gasifier, each biomass is thrown into high temperature zone in the reactor. In order to simulate the reaction occurred in a fluidized bed rapid pyrolyzer/gasifier, the reactor was designed to inject samples into reaction zone directly and to control the reaction time optionally. Rapid pyrolysis of wood biomasses, such as Konara, bagasse, and EFB (Empty Fruit Bunch), was carried out at 1073K in nitrogen with the reaction time range of 2-20s. Difference in product distribution with varying reaction time was observed apparently among Konara, bagasse, and EFB. The difference in the reactivity among sorts of biomass should be considered even when their elemental composition and/or components ratio are similar. Rapid pyrolysis of wood biomass (Japanese cedar) with small amount of oxygen as gasification agent was also carried out. The amount of product gas was decreased through 1s to 2s and the decreasing rate was higher with increase in the amount of oxygen.

  10. Pyrolysis derivatization of humic substances.1. Pyrolysis of fulvic acids in the presence of tetramethylammonium hydroxide

    OpenAIRE

    Martín Martínez, Francisco; González-Vila, Francisco Javier; Río Andrade, José Carlos del; Verdejo Robles, Trinidad

    1994-01-01

    Pyrograms of three fulvic acids (FAs) of different origins and the corresponding pyrograms obtained by reactive pyrolysis with tetramethylammonium hydroxide (TMAH) are compared. This procedure introduces both striking qualitative and quantitative changes in the pyrolytic patterns of the FAs, which are discussed in terms of the usefulness of this approach to structural studies. Some non-pyrolysis compounds (probably retained in the macromolecular fulvic matrix) seem to be released when the FAs...

  11. Effect of wastewater treatment processes on the pyrolysis properties of the pyrolysis tars from sewage sludges

    Science.gov (United States)

    Wu, Xia; Xie, Li-Ping; Li, Xin-Yu; Dai, Xiao-Hong; Fei, Xue-Ning; Jiang, Yuan-Guang

    2011-06-01

    The pyrolysis properties of five different pyrolysis tars, which the tars from 1# to 5# are obtained by pyrolyzing the sewage sludges of anaerobic digestion and indigestion from the A2/O wastewater treatment process, those from the activated sludge process and the indigested sludge from the continuous SBR process respectively, were studied by thermal gravimetric analysis at a heating rate of 10 °C/min in the nitrogen atmosphere. The results show that the pyrolysis processes of the pyrolysis tars of 1#, 2#, 3# and 5# all can be divided into four stages: the stages of light organic compounds releasing, heavy polar organic compounds decomposition, heavy organic compounds decomposition and the residual organic compounds decomposition. However, the process of 4# pyrolysis tar is only divided into three stages: the stages of light organic compounds releasing, decomposition of heavy polar organic compounds and the residual heavy organic compounds respectively. Both the sludge anaerobic digestion and the "anaerobic" process in wastewater treatment processes make the content of light organic compounds in tars decrease, but make that of heavy organic compounds with complex structure increase. Besides, both make the pyrolysis properties of the tars become worse. The pyrolysis reaction mechanisms of the five pyrolysis tars have been studied with Coats-Redfern equation. It shows that there are the same mechanism functions in the first stage for the five tars and in the second and third stage for the tars of 1#, 2#, 3# and 5#, which is different with the function in the second stage for 4# tar. The five tars are easy to volatile.

  12. Pyrolysis of flax straw: Characterization of char, liquid, and gas as fuel

    Science.gov (United States)

    Tushar, Mohammad Shahed Hasan Khan

    The demand for energy continues to outstrip its supply and necessitates the development of renewable energy options. Biomass has been recognized as a major renewable energy source to supplement the declining fossil fuel source of energy. It is the most popular form of renewable energy and, currently, biofuel production is becoming more promising. Being carbon neutral, readily available, and low in sulphur content makes biomass a very promising source of renewable energy. In the present research, both the isothermal and non-isothermal pressurized pyrolysis of flax straw is studied for the first time. In case of isothermal pyrolysis, the influence of pyrolysis temperature and reaction time on char yield and morphology was investigated. The applied pyrolysis temperature was varied between 300 and 500°C. The reaction time was varied from 15 to 60 min. The char yield was found to decrease as pyrolysis temperature and reaction time increased. The char structure and surface morphology were thoroughly investigated by means of x-ray diffraction (XRD), temperature-programmed oxidation (TPO), and scanning electron microscopy (SEM). The degree of porosity and graphitization increased as pyrolysis temperature and time increased. In fact, the experiment performed at 500°C for 1h duration did not yield any char; only residual ash could be obtained. The TPO studies on the char samples corroborated the XRD findings and showed the presence of two types of carbon, namely, amorphous filamentous carbon and graphitic carbon. A thermogravimetric analysis (TGA) of the char was performed to gain an understanding of combustion kinetics and reactivity. It implied that the reactivity of the char decreases as temperature increases, and this finding is well supported by the TPO, TGA, SEM, and XRD characterization data. Furthermore, an empirical global model was devised based on the power law to estimate activation energy and other kinetic parameters. For the non-isothermal pressurized pyrolysis of flax straw, the experiments were carried out at different pressures, ranging from 10 to 40 psig. The three types of products thus obtained (gas, liquid, char) were thoroughly quantified and analyzed. The yields of the products were found to be dependent on the experimental conditions. It was observed that 10 psig of pressure gave the maximum yield of bio-oil, while 20 psig pressure lead to maximum char yield. The gaseous products were analyzed using an online GC, while the