Cobalt catalysts for the conversion of methanol and for Fischer-tropsch synthesis to produce hydrocarbons

International Nuclear Information System (INIS)

Mauldin, C.H.; Davis, S.M.; Arcuri, K.B.

1987-01-01

A regeneration stable catalyst is described for the conversion at reaction conditions of methanol or synthesis gas to liquid hydrocarbons which consists essentially of from about 2 percent to about 25 percent cobalt, based on the weight of the catalyst composition, composited with titania, or a titania-containing support, to which is added sufficient of a zirconium, hafnium, cerium, or uranium promoter to provide a weight ratio of the zirconium, hafnium, cerium, or uranium metal:cobalt greater than about 0.101:1

Process for preparing hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Krauch, C; Anther, E; Pier, M

1926-04-07

A process is described for the conversion of coal of all kinds, wood, oil, shale, as well as other carbonaceous materials into liquid hydrocarbons in two steps, characterized by treatment of the coal and so forth with a stream of hydrogen or hydrogen-containing gases at raised temperatures and raised pressures and producing a tarry product which, after separation of the ashlike residue, is converted by a further treatment, in the presence of catalysts, with hydrogen or hydrogen-containing gases at raised temperature and pressure, largely into low-boiling products.

Toward Singlet-Triplet Bistable Nonalternant Kekulé Hydrocarbons: Azulene-to-Naphthalene Rearrangement.

Science.gov (United States)

Das, Soumyajit; Wu, Jishan

2015-12-04

Recent developments of open-shell singlet diradicaloids motivated the search for stable singlet-triplet bistable nonalternant polycyclic hydrocarbons. During the synthesis of this type of molecule, such as the dibenzo-cyclohepta[def]fluorene 3, an unexpected azulene-to-naphthalene rearrangement was observed at room temperature, which resulted in new nonalternant hydrocarbons 8a/8b with a closed-shell singlet ground state. These studies provided insight into the unique chemistry of azulene and challenges for the synthesis of singlet-triplet bistable polycyclic hydrocarbons.

Polycyclic Aromatic Compounds as Anticancer Agents: Synthesis and Biological Evaluation of Methoxy Dibenzofluorene Derivatives

Directory of Open Access Journals (Sweden)

Bimal Krishna Banik

2014-08-01

Full Text Available Synthesis of a new methoxy dibenzofluorene through alkylation, cyclodehydration and aromatization in a one-pot operation is achieved for the first time. Using this hydrocarbon, a few derivatives are prepared through aromatic nitration, catalytic hydrogenation, coupling reaction with a side chain and reduction. The benzylic position of this hydrocarbon with the side chain is oxidized and reduced. Some of these derivatives have demonstrated excellent antitumor activities in vitro. This study confirms antitumor activity depends on the structures of the molecules.

Synthesis, characterization and reactivity of some lanthanide organometallics

International Nuclear Information System (INIS)

Marchal, N.

1991-12-01

Organo lanthanides with reactive metal-carbon bonds are obtained by direct synthesis of the metal (powder) and a hydrocarbon in ether medium, like with alkali metals. Two types of synthesis are envisaged: formation of covalent bonds by opening cycles, only biphenylene is reactive enough in regard to ytterbium and samarium, these organometallic compounds can also be prepared by the classical way, i.e. reaction of 2.2'-dilithio biphenyl on rare earth halogenides and coupling of 6.6-dimethylfulvene leading to dicyclopentadienyl compounds with Sm and Yb. The reactivity of these complexes is studied by catalysis of ethylene polymerization

Selective Synthesis of Gasoline-Ranged Hydrocarbons from Syngas over Hybrid Catalyst Consisting of Metal-Loaded ZSM-5 Coupled with Copper-Zinc Oxide

Directory of Open Access Journals (Sweden)

Ting Ma

2014-04-01

Full Text Available The conversion of syngas (CO + H2 to gasoline-ranged hydrocarbons was carried out using a hybrid catalyst consisting of metal-loaded ZSM-5 coupled with Cu-ZnO in a near-critical n-hexane solvent. Methanol was synthesized from syngas over Cu-ZnO; subsequently, was converted to hydrocarbons through the formation of dimethyl ether (DME over the metal-loaded ZSM-5. When 0.5 wt% Pd/ZSM-5 and 5 wt% Cu/ZSM-5 among the metal-loaded ZSM-5 catalysts with Pd, Co, Fe or Cu were employed as a portion of the hybrid catalyst, the gasoline-ranged hydrocarbons were selectively produced (the gasoline-ranged hydrocarbons in all hydrocarbons: 59% for the hybrid catalyst with Pd/ZSM-5 and 64% for that with Cu/ZSM-5 with a similar CO conversion during the reaction. An increase in the Cu loading on ZSM-5 resulted in increasing the yield of the gasoline-ranged hydrocarbons, and in decreasing the yield of DME. Furthermore, the hybrid catalyst with Cu/ZSM-5 exhibited no deactivation for 30 h of the reaction. It was revealed that a hybrid catalyst containing Cu/ZSM-5 was efficient in the selective synthesis of gasoline-ranged hydrocarbons from syngas via methanol in the near-critical n-hexane fluid.

Preparation of 18F-FDG by basic hydrolysis on '1-pot' FDG synthesis module

International Nuclear Information System (INIS)

Li Qiming; Jin Rongbing; Fan Xijiang

2007-01-01

'1-pot' equipment is an automatic synthesis module of producing 18 F-FDG by acid hydrolysis process. Simple changes in the chemistry, plumbing, and programming of CPCU enable two back-to-back '1-pot' systems in a unit. The preparation of precursor of 18 F-FDG is the same with origin. The results of experiments showed that by basic hydrolysis procedure, the synthesis time is shorten from 45-50 min to 30-35 min, uncorrected synthesis yield can be increased from 45%-50% to 60%-65%, and the preparing procedure is stable. The quality of 18 F-FDG meets the requirements under USP fludeoxyglucose 18 F injection, radiochemical purity is more than 99% especially by HPLC. With '1-pot' FDG synthesis module Chemical Processing Control Unit (CPCU), 18 F-FDG can be prepared by basic hydrolysis process. (authors)

Combustion synthesis: A new approach for preparation of thermoelectric zinc antimonide compounds

Energy Technology Data Exchange (ETDEWEB)

Rouessac, F., E-mail: Florence.Rouessac@univ-montp2.fr [Institut Charles Gerhardt Montpellier, UMR 5253 CNRS-UM2-ENSCM-UM1, C2M Universite Montpellier 2, CC 1504 Place Eugene Bataillon, 34095 Montpellier Cedex 5 (France); Ayral, R.-M. [Institut Charles Gerhardt Montpellier, UMR 5253 CNRS-UM2-ENSCM-UM1, C2M Universite Montpellier 2, CC 1504 Place Eugene Bataillon, 34095 Montpellier Cedex 5 (France)

2012-07-25

Highlights: Black-Right-Pointing-Pointer Reliable preparation method of thermoelectric materials. Black-Right-Pointing-Pointer Formation of zinc antimonide by the combustion synthesis method is investigated. Black-Right-Pointing-Pointer XRD and Raman spectroscopy as a function of temperature. Black-Right-Pointing-Pointer SHS: a new way for synthesizing thermoelectric materials. - Abstract: Due to the interesting properties of Zn{sub 4}Sb{sub 3} thermoelectric material, a reliable preparation method of this material is required. In this study, the formation of zinc antimonides by the combustion synthesis method is investigated and subjected to characterization using X-ray diffraction and Raman spectroscopy as a function of temperature. The results show that combustion synthesis can be a new way for synthesizing these thermoelectric materials.

The Synthesis, Characterization and Catalytic Reaction Studies of Monodisperse Platinum Nanoparticles in Mesoporous Oxide Materials

Energy Technology Data Exchange (ETDEWEB)

Rioux, Robert M. [Univ. of California, Berkeley, CA (United States)

2006-01-01

A catalyst design program was implemented in which Pt nanoparticles, either of monodisperse size and/or shape were synthesized, characterized and studied in a number of hydrocarbon conversion reactions. The novel preparation of these materials enables exquisite control over their physical and chemical properties that could be controlled (and therefore rationally tuned) during synthesis. The ability to synthesize rather than prepare catalysts followed by thorough characterization enable accurate structure-function relationships to be elucidated. This thesis emphasizes all three aspects of catalyst design: synthesis, characterization and reactivity studies. The precise control of metal nanoparticle size, surface structure and composition may enable the development of highly active and selective heterogeneous catalysts.

Preparation of 16α[18F] fluoro-17β-fluoroestradiol on domestic synthesis module

International Nuclear Information System (INIS)

Sun Chuanjin; Zhu Hong; Fang Keyuan

2012-01-01

To investigate the synthesis method of 16α-[ 18 F] fluoro-17β-fluoroestradiol on domestic synthesizing module, the automated synthesis was carried out through the reaction of 3-O-(methoxymethyl) -16,17-O-sulfuryl-16-epiestriol (MMSE, 1 mg) as precursor with 18 F- at 105 ℃ for 15 min in sealed system on domestic synthesizer, then 0.8 mL 1 mol/L HC1 dissolved in 7.2 mL acetonetrile was added in three parts to the reaction vessel for hydrolysis and hydrolysis reaction was performed at 105 ℃ for 6 min. The final reaction solution was purified by HPLC to give 18 F-FES. Preparation of 18 F-FES on domestic synthesis module was in the uncorrected synthesis yield of 8.2% (corrected synthesis yield 12.8%). Total synthesis time was about 70 min and radiochemical purity was higher than 98%. The product had good stability at room temperature. 18 F-FES injection can be prepared on domes- tic synthesis module and the quality can meet the requirements of radiopharmaceuticals for clinical use, (authors)

Detection of radiation-induced hydrocarbons in baked sponged cake prepared with irradiated liquid egg

Science.gov (United States)

Schulzki, G.; Spiegelberg, A.; Bögl, K. W.; Schreiber, G. A.

1995-02-01

For identification of irradiated food, radiation-induced volatile hydrocarbons (HC) are determined by gas chromatography in the non-polar fraction of fat. However, in complex food matrices the detection is often disturbed by fat-associated compounds. On-line coupling of high performance liquid chromatography (LC) and gas chromatography (GC) is very efficient to remove such compounds from the HC fraction. The high sensitivity of this fast and efficient technique is demonstrated by the example of detection of radiation-induced HC in fat isolated from baked sponge cake which had been prepared with irradiated liquid egg.

Study of barium bismuth titanate prepared by mechanochemical synthesis

Directory of Open Access Journals (Sweden)

Lazarević Z.Ž.

2009-01-01

Full Text Available Barium-bismuth titanate, BaBi4Ti4O15 (BBT, a member of Aurivillius bismuth-based layer-structure perovskites, was prepared from stoichiometric amounts of barium titanate and bismuth titanate obtained via mechanochemical synthesis. Mechanochemical synthesis was performed in air atmosphere in a planetary ball mill. The reaction mechanism of BaBi4Ti4O15 and the preparation and characteristics of BBT ceramic powders were studied using XRD, Raman spectroscopy, particle analysis and SEM. The Bi-layered perovskite structure of BaBi4Ti4O15 ceramic forms at 1100 °C for 4 h without a pre-calcination step. The microstructure of BaBi4Ti4O15 exhibits plate-like grains typical for the Bi-layered structured material and spherical and polygonal grains. The Ba2+ addition leads to changes in the microstructure development, particularly in the change of the average grain size.

Formation of hydrocarbons by bacteria and algae

Energy Technology Data Exchange (ETDEWEB)

Tornabene, T.G.

1980-12-01

A literature review has been performed summarizing studies on hydrocarbon synthesis by microorganisms. Certain algal and bacterial species produce hydrocarbons in large quantities, 70 to 80% of dry cell mass, when in a controlled environment. The nutritional requirements of these organisms are simple: CO/sub 2/ and mineral salts. The studies were initiated to determine whether or not microorganisms played a role in petroleum formation. 90 references. (DMC)

Synthesis of carbon nanotube using camphor with SS 316 as catalytic substrate via oxidative heat treatment preparation method

Science.gov (United States)

Wulan, Praswasti Pembangun Dyah Kencana; Angelina, Dian

2017-11-01

Carbon nanotube (CNT) is a material that now often become the topic in nanotechnology research. CNT is widely used in the electronics industry especially for TV and computer flat panel displays, devices, automotives for car components, and batteries. Also for defense industries as well as other industries such as sports equipment. Camphor (C10H16O), a botanical hydrocarbon, can be used as a renewable and low cost carbon source for CNT synthesis. Synthesis was performed with stainless steel-316 (SS 316) as substrate, argon as carrier gas, and hydrogen as co-reactant. Preparation of the SS 316 was through a pretreatment by oxidative heat treatment method at a temperature of 850oC for 30 minutes, to remove the layer of chrome and make a rough surface as a growth media for CNT. The operating temperature of the synthesis used was 800oC with a reaction time of 60 minutes. Reactor, which made from stainless steel 316 (SS 316), was used for synthesis CNTs with maximum camphor mass of 20 grams. This research was conducted by varying the number of camphor mass by 5, 7, 10, 12, and 15 grams. The results showed that camphor decomposed into three compounds which are 40% benzene, 8% toluene, and 52% xylene. CNT grows on the surface of the SS 316 plate for each variation. CNTs have grown by follow tips growth model with deformations like buckling growth model and continuous growth model were also founded. The results of XRD showed that CNT were found in every camphor mass variation with high intensity at 2θ angle of 26° and 43°. The best quality and yield of CNT was obtained at camphor mass of 15 grams with carbon percentage of 87,1% and diameter 33 - 44 nm.

Ethanol synthesis and water gas shift over bifunctional sulfide catalysts. Final technical progress report, September 12, 1991--December 11, 1994

Energy Technology Data Exchange (ETDEWEB)

Klier, K.; Herman, R.G.; Deemer, M.; Richards-Babb, M.; Carr, T.

1995-07-01

The objective of this research was to investigate sulfur-resistant catalysts for the conversion of synthesis gas having H{sub 2}/CO {le} 1 into C{sub 1}--C{sub 4} alcohols, especially ethanol, by a highly selective and efficient pathway, while also promoting the water gas shift reaction (WGSR). The catalysts chosen are bifunctional, base-hydrogenation, sulfur-tolerant transition metal sulfides with heavy alkali, e.g. Cs{sup +}, promoter dispersed on their surfaces. The modes of activation of H{sub 2} and CO on MoS{sub 2} and alkali-doped MoS{sub 2} were considered, and computational analyses of the thermodynamic stability of transition metal sulfides and of the electronic structure of these sulfide catalysts were carried out. In the preparation of the cesium-promoted MoS{sub 2} catalysts, a variety of preparation methods using CsOOCH were examined. In all cases, doping with CsOOCH led to a lost of surface area. The undoped molybdenum disulfide catalyst only produced hydrocarbons. Cs-doped MoS{sub 2} catalysts all produced linear alcohols, along with smaller amounts of hydrocarbons. With a 20 wt% CsOOCH/MoS{sub 2} catalyst, temperature, pressure, and flow rate dependences of the synthesis reactions were investigated in the presence and absence of H{sub 2}S in the H{sub 2}/CO = 1/1 synthesis gas during short term testing experiments. It was shown that with a carefully prepared 10 wt% CsOOCH/MoS{sub 2} catalyst, reproducible and high alcohol synthesis activity could be obtained. For example, at 295 C with H{sub 2}/CO = 1 synthesis gas at 8.3 MPa and with GHSV = 7,760 l/kg cat/hr, the total alcohol space time yield was ca 300 g/kg cat/hr (accompanied with a hydrocarbon space time yield of ca 60 g/kg cat/hr). Over a testing period of ca 130 hr, no net deactivation of the catalyst was observed. 90 refs., 82 figs., 14 tabs.

Sol gel synthesis for preparation of yttrium aluminium garnet

NARCIS (Netherlands)

Vrolijk, J.W.G.A.; Willems, J.W.M.M.; Metselaar, R.; With, de G.; Terpstra, R.A.; Metselaar, R.

1989-01-01

Sol-gel—synthesis for preparation of pure yttrium aluminium garnet powder with small grain size is subject of this ongoing study. Starting materials were sulfates and chlorides of yttrium and aluminium. To obtain pure YAG (Y3A1SO1Z) pH during hydrolysis as well as temperature during calcination and

Preparation of molybdenum borides by combustion synthesis involving solid-phase displacement reactions

International Nuclear Information System (INIS)

Yeh, C.L.; Hsu, W.S.

2008-01-01

Preparation of molybdenum borides of five different phases in the Mo-B binary system (including Mo 2 B, MoB, MoB 2 , Mo 2 B 5 , and MoB 4 ) was performed by self-propagating high-temperature synthesis (SHS) with two kinds of the reactant samples. When elemental powder compacts with an exact stoichiometry corresponding to the boride phase were employed, self-sustaining reaction was only achieved in the sample with Mo:B = 1:1 and nearly single-phase MoB was yielded. Therefore, the other four boride compounds were prepared from the reactant compacts composed of MoO 3 , Mo, and B powders, within which the displacement reaction of MoO 3 with boron was involved in combustion synthesis. Experimental evidence shows that the extent of displacement reaction in the overall reaction has a significant impact on sustainability of the synthesis reaction, combustion temperature, reaction front velocity, and composition of the end product. An increase in the solid-phase displacement reaction taking place during the SHS process contributes more heat flux to the synthesis reaction, thus resulting in the increase of combustion temperature and enhancement of the reaction front velocity. Based upon the XRD analysis, formation of Mo 2 B, MoB 2 , and Mo 2 B 5 as the dominant boride phase in the end product was successful through the SHS reaction with powder compacts under appropriate stoichiometries between MoO 3 , Mo, and B. However, a poor conversion was observed in the synthesis of MoB 4 . The powder compact prepared for the production of MoB 4 yielded mostly Mo 2 B 5

Detection of radiation-induced hydrocarbons in baked sponge cake prepared with irradiated liquid egg

International Nuclear Information System (INIS)

Schulzki, G.; Spiegelberg, A.; Boegl, K.W.; Schreiber, G.A.

1995-01-01

For identification of irradiated food, radiation-induced volatile hydrocarbons (HC) are determined by gas chromatography in the non-polar fraction of fat. However, in complex food matrices the detection is often disturbed by fat-associated compounds. On-line coupling of high performance liquid chromatography (LC) and gas chromatography (GC) is very efficient to remove such compounds from the HC fraction. The high sensitivity of this fast and efficient technique is demonstrated by the example of detection of radiation-induced HC in fat isolated from baked sponge cake which had been prepared with irradiated liquid egg. (Author)

Synthesis of carbon-14-labeled sodium palmoxirate and its coenzyme A ester

Energy Technology Data Exchange (ETDEWEB)

Weaner, L.E.; Hoerr, D.C.

1986-04-01

Synthetic procedures for the preparation of carbon-14-labeled sodium palmoxirate (TDGA), labeled either in the carboxyl position or in the tetradecyl hydrocarbon chain, are described. In addition, the synthesis of the coenzyme A ester of TDGA-14C with a specific activity of 51 mCi/mmol is reported. The coenzyme A ester was prepared by formation of the acyl chloride with oxalyl chloride followed by reaction with coenzyme A (CoA) in a borate-buffered tetrahydrofuran solution. Purification methods and analytical and stability data are reported for the compounds.

A reproducible and scalable procedure for preparing bacterial extracts for cell-free protein synthesis.

Science.gov (United States)

Katsura, Kazushige; Matsuda, Takayoshi; Tomabechi, Yuri; Yonemochi, Mayumi; Hanada, Kazuharu; Ohsawa, Noboru; Sakamoto, Kensaku; Takemoto, Chie; Shirouzu, Mikako

2017-11-01

Cell-free protein synthesis is a useful method for preparing proteins for functional or structural analyses. However, batch-to-batch variability with regard to protein synthesis activity remains a problem for large-scale production of cell extract in the laboratory. To address this issue, we have developed a novel procedure for large-scale preparation of bacterial cell extract with high protein synthesis activity. The developed procedure comprises cell cultivation using a fermentor, harvesting and washing of cells by tangential flow filtration, cell disruption with high-pressure homogenizer and continuous diafiltration. By optimizing and combining these methods, ∼100 ml of the cell extract was prepared from 150 g of Escherichia coli cells. The protein synthesis activities, defined as the yield of protein per unit of absorbance at 260 nm of the cell extract, were shown to be reproducible, and the average activity of several batches was twice that obtained using a previously reported method. In addition, combinatorial use of the high-pressure homogenizer and diafiltration increased the scalability, indicating that the cell concentration at disruption varies from 0.04 to 1 g/ml. Furthermore, addition of Gam protein and examinations of the N-terminal sequence rendered the extract prepared here useful for rapid screening with linear DNA templates. © The Authors 2017. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

Preparation of high exhaust chrome from leather shavings and hydrocarbons with its application in leather processing for green tanning technology

International Nuclear Information System (INIS)

Nawaz, H.R.; Solangi, B.A.; Nadeem, U.; Zehra, B.

2010-01-01

The use of chrome in tanning has made the remarkable advances to achieve the best quality and quantity of leather. But the chrome tanning process is associated with the generation of heavy metal containing solid wastes and toxic effluents. To solve the environmental issues we emphasized on the development of high exhaust chrome complex from chrome containing leather wastes that could minimize the toxic effluents up to negligible limit. Therefore in the synthetic process of chrome tanning material, the chrome shavings and the hydrocarbons have been utilized as a reductant as well as the potential masking intermediates. These chrome tanning materials have been prepared using leather shavings alone in product A, partial replacement of shavings by hydrocarbons for product B and then replacement of hydrocarbons by molasses for product C. The materials have been employed for the tanning of goat skins parallel to the commercial basic chromium sulfate (BCS). (author)

Synthesis, characterization, and Fischer–Tropsch performance of cobalt/zinc aluminate nanocomposites via a facile and corrosion-free coprecipitation route

International Nuclear Information System (INIS)

Liu, Zhenxin; Xing, Yu; Xue, Yingying; Wu, Depeng; Fang, Shaoming

2015-01-01

Literature about ZnAl 2 O 4 -supported cobalt Fischer–Tropsch synthesis (FTS) catalytic materials is sparse. A series of cobalt-containing nanocomposites, supported by nanosized ZnAl 2 O 4 spinel (i.e., a complex oxide of about 6.4 nm) or alumina (i.e., a simple oxide of about 6.2 nm), were prepared via urea-gelation, coprecipitation, or impregnation methods followed by stepwise reduction. These materials were examined by XRD, TGA, nitrogen sorption, FESEM, and EDS. Effects of corrosion and pore size distributions on materials preparation were also investigated. The “coprecipitation/stepwise reduction” route is facile and suitable to prepare nanosized ZnAl 2 O 4 -supported Co 0 nanocomposites. At similar CO conversions, the coprecipitated Co/ZnAl 2 O 4 exhibits significantly lower C 1 hydrocarbon distribution, slightly lower C 5+ hydrocarbon distribution, significantly higher C 2 –C 4 hydrocarbon distribution, and significantly higher olefin/paraffin ratio of C 2 –C 4 than Co/γ-Al 2 O 3

Novel magnetic nanoparticles coated by benzene- and β-cyclodextrin-bearing dextran, and the sorption of polycyclic aromatic hydrocarbon

DEFF Research Database (Denmark)

Cho, Eunae; Tahir, Muhammad Nazir; Min Choi, Jae

2015-01-01

We present the synthesis of novel magnetic nanoparticles functionalized by benzene- and β-cyclodextrin-derivatized dextran. The grafting strategy was based on the [alkynyl-iron] cluster in the modified dextrans, which were prepared by click reaction from alkyne-modified dextran and benzyl azide......, the potential for removing polycyclic aromatic hydrocarbons such as phenanthrene and pyrene by sorption onto the nanomaterials was assessed. In the sorption, pi-stacking interactions of the benzene-derivatized dextran and host–guest chemistry of the β-cyclodextrin-derivatized dextran were considered...

Performance estimation of ejector cycles using heavier hydrocarbon refrigerants

International Nuclear Information System (INIS)

Kasperski, Jacek; Gil, Bartosz

2014-01-01

Computer software basing on theoretical model of Huang et al. with thermodynamic properties of hydrocarbons was prepared. Investigation was focused on nine hydrocarbons: propane, butane, iso-butane, pentane, iso-pentane, hexane, heptane and octane. A series of calculations was carried out for the generator temperature between 70 and 200 °C, with assumed temperatures of evaporation 10 °C and condensation 40 °C. Calculation results show that none of the hydrocarbons enables high efficiency of a cycle in a wide range of temperature. Each hydrocarbon has its own maximal entrainment ratio at its individual temperature of optimum. Temperatures of entrainment ratios optimum increase according to the hydrocarbon heaviness with simultaneous increase of entrainment ratio peak values. Peak values of the COP do not increase according to the hydrocarbons heaviness. The highest COP = 0.32 is achieved for iso-butane at 102 °C and the COP = 0.28 for pentane at 165 °C. Heptane and octane can be ignored. - Highlights: • Advantages of use of higher hydrocarbons as ejector refrigerants were presumed. • Computer software basing on theoretical model of Huang et al. (1999) was prepared. • Optimal temperature range of vapor generation for each hydrocarbon was calculated

Synthesis of Hydrocarbons from H2-Deficient Syngas in Fischer-Tropsch Synthesis over Co-Based Catalyst Coupled with Fe-Based Catalyst as Water-Gas Shift Reaction

Directory of Open Access Journals (Sweden)

Ting Ma

2015-01-01

Full Text Available The effects of metal species in an Fe-based catalyst on structural properties were investigated through the synthesis of Fe-based catalysts containing various metal species such, as Mn, Zr, and Ce. The addition of the metal species to the Fe-based catalyst resulted in high dispersions of the Fe species and high surface areas due to the formation of mesoporous voids about 2–4 nm surrounded by the catalyst particles. The metal-added Fe-based catalysts were employed together with Co-loaded beta zeolite for the synthesis of hydrocarbons from syngas with a lower H2/CO ratio of 1 than the stoichiometric H2/CO ratio of 2 for the Fischer-Tropsch synthesis (FTS. Among the catalysts, the Mn-added Fe-based catalyst exhibited a high activity for the water-gas shift (WGS reaction with a comparative durability, leading to the enhancement of the CO hydrogenation in the FTS in comparison with Co-loaded beta zeolite alone. Furthermore, the loading of Pd on the Mn-added Fe-based catalyst enhanced the catalytic durability due to the hydrogenation of carbonaceous species by the hydrogen activated over Pd.

Organic synthesis

Energy Technology Data Exchange (ETDEWEB)

Thomas, S.E.

1991-01-01

This paper reports on reactions of organoboranes. Organoboron routes to unsaturated hydrocarbons. Boronic ester homologation. Properties of organosilicon compounds. Alkene synthesis (Peterson olefination). Allylsilanes and acylsilanes.

PETI-298 Prepared by Microwave Synthesis: Neat Resin and Composite Properties

Science.gov (United States)

Smith, Joseph G.; Connell, John W.; Li, Chao-Jun; Wu, Wei; Criss, Jim M., Jr.

2004-01-01

PETI-298 is a high temperature/high performance matrix resin that is processable into composites by resin transfer molding (RTM), resin infusion and vacuum assisted RTM techniques. It is typically synthesized in a polar aprotic solvent from the reaction of an aromatic anhydride and a combination of diamines and endcapped with phenylethynylphthalic anhydride. Microwave synthesis of PETI-298 was investigated as a means to eliminate solvent and decrease reaction time. The monomers were manually mixed and placed in a microwave oven for various times to determine optimum reaction conditions. The synthetic process was subsequently scaled-up to 330g. Three batches were synthesized and combined to give 1 kg of material that was characterized for thermal and rheological properties and compared to PETI-298 prepared by the classic solution based synthetic method. The microwave synthesized PETI-298 was subsequently used to fabricate flat laminates on T650 carbon fabric by RTM. The composite panels were analyzed and mechanical properties determined and compared with those fabricated from PETI-298 prepared by the classic solution method. The microwave synthesis process and characterization of neat resin and carbon fiber reinforced composites fabricated by RTM will be presented. KEY WORDS: Resin Transfer Molding, High Temperature Polymers, Phenylethynyl Terminated Imides, Microwave Synthesis

An automated synthesis module for preparation of L-3-[123I]iodo-alpha-methyl tyrosine

International Nuclear Information System (INIS)

Luurtsema, Gert; Jager, Pieter L.; Piers, Albertus; Hooge, Marjolijn N. de

2001-01-01

L-3-[ 123 I]iodo-alpha-methyl tyrosine (IMT) is an artificial amino acid suitable for SPECT imaging of various tumours. Manual synthesis of this radiopharmaceutical is reliable, but time-consuming and may require handling of large quantities of radioactivity. We developed an automated IMT synthesis module, which prepares a ready-to-inject product that meets radiopharmaceutical requirements and is identical to the manually synthesised equivalent. Current advantages include decreased operator assistance time and reduced radiation exposure. Application may be extended to other radiopharmaceuticals, including high-dose preparations for therapeutic use

[Pattern of growth and metabolism of thermotolerant microorganisms on media containing carbohydrates and hydrocarbons].

Science.gov (United States)

Kvasnikov, E I; Isakova, D M; Eliseeva, G S; Loiko, Z I

1977-01-01

Experiments were carried out to examine the growth and metabolism of thermotolerant yeast Candida tropicalis K-41 and bacteria Micrococcus freudenreichii that do not have a single temperature point but instead have an optimal temperature plateau at which the growth rate and biosynthetic activity remain unaltered or change insignificantly. Upon transition from the carbohydrate to the hydrocarbon pattern of nutrition these microorganisms show significant changes in metabolic processes: optimal concentration of biotin in the medium decreases significantly; the synthesis of riboflavin, nicotinic and pantothenic acids increases in yeast; the synthesis of nicotinic acid, biotin and vitamin B12 increases in bacteria. During microbial cultivation on hydrocarbons the content of cell lipids grows; yeast accumulate actively phospholipids and free fatty acids; bacteria build up intensively waxes and phospholipids. With the near-maximal growth rate the total synthesis of lipids decreases on carbohydrates and increases drastically on hydrocarbons, primarily at the expense of the above fractions.

Bioremediation of soils containing petroleum hydrocarbons, chlorinated phenols, and polycyclic aromatic hydrocarbons

International Nuclear Information System (INIS)

Seech, A.; Burwell, S.; Marvan, I.

1994-01-01

Bench-scale treatability investigations, pilot-scale and full-scale bioremediation projects were conducted to evaluate Daramend trademark bioremediation of soils containing petroleum hydrocarbons, heavy oils, paraffins, chlorinated phenols and polycyclic aromatic hydrocarbons (PAHs). Bench-scale investigations were conducted using glass microcosms. Pilot-scale and full-scale demonstrations were conducted at industrial sites and included treatment of excavated soils and sediments in on-site cells constructed using synthetic liners and covered by steel/polyethylene structures as well as in-situ treatment. A total of approximately 5,000 tons of soil was treated. The soil treatment included organic soil amendments, specialized tillage/aeration apparatus, and strict control of soil moisture. The amendments are composed of naturally-occurring organic materials prepared to soil-specific particle size distributions, nutrient profiles, and nutrient-release kinetics. Bench-scale work indicated that in refinery soil containing high concentrations of heavy oils, extractable hydrocarbon concentrations could be rapidly reduced to industrial clean-up criteria, and that the hydrocarbons were fully mineralized with release of CO 2

Method of preparing highly active and thermostable preparations of liver uridin-kinase usable for enzymic synthesis of radioactive nucleoside-5'-phosphates

International Nuclear Information System (INIS)

Cihak, A.; Vesely, J.

1975-01-01

A method is described of preparing a high-activity uridine kinase for the enzymic synthesis of radioactive nucleoside-5m-phosphates of the pyrimidine series. The preparation is separated from male rat liver after intraperitoneal application of 5'-azacytidine. Examples are given showing detailed procedures for the conversion of uridine and 6-azauridine to the corresponding 5'-phosphates. (L.K.)

Radiation-induced volatile hydrocarbon production in platelets

International Nuclear Information System (INIS)

Radha, E.; Vaishnav, Y.N.; Kumar, K.S.; Weiss, J.F.

1989-01-01

Generation of volatile hydrocarbons (ethane, pentane) as a measure of lipid peroxidation was followed in preparations from platelet-rich plasma irradiated in vitro. The hydrocarbons in the headspace of sealed vials containing irradiated and nonirradiated washed platelets, platelet-rich plasma, or platelet-poor plasma increased with time. The major hydrocarbon, pentane, increased linearly and significantly with increasing log radiation dose, suggesting that reactive oxygen species induced by ionizing radiation result in lipid peroxidation. Measurements of lipid peroxidation products may give an indication of suboptimal quality of stored and/or irradiated platelets

Syngas Conversion to Gasoline-Range Hydrocarbons over Pd/ZnO/Al2O3 and ZSM-5 Composite Catalyst System

Energy Technology Data Exchange (ETDEWEB)

Dagle, Robert A.; Lizarazo Adarme, Jair A.; Lebarbier, Vanessa MC; Gray, Michel J.; White, James F.; King, David L.; Palo, Daniel R.

2014-07-01

A composite Pd/ZnO/Al2O3-HZSM-5 (Si/Al=40) catalytic system was evaluated for the synthesis of gasoline-range hydrocarbons directly from synthesis gas. Bifunctional catalyst comprising PdZn metal and acid sites present the required catalytically active sites necessary for the methanol synthesis, methanol dehydration, and methanol-to-gasoline reactions. This system provides a unique catalytic pathway for the production of liquid hydrocarbons directly from syngas. However, selectivity control is difficult and poses many challenges. The composite catalytic system was evaluated under various process conditions. Investigated were the effects of temperature (310-375oC), pressure (300-1000 psig), time-on-stream (50 hrs), and gas-hour space velocity (740-2970 hr-1), using a H2/CO molar syngas ratio of 2.0. By operating at the lower end of the temperature range investigated, liquid hydrocarbon formation was favored, as was decreased amounts of undesirable light hydrocarbons. However, lower operating temperatures also facilitated undesirable CO2 formation via the water-gas shift reaction. Higher operating pressures slightly favored liquid synthesis. Operating at relatively low pressures (e.g. 300 psig) was made possible, whereas for methanol synthesis alone higher pressure are usually required to achieve similar conversion levels (e.g. 1000 psig). Thermodynamic constraints on methanol synthesis are eased by pushing the equilibrium through hydrocarbon formation. Catalytic performance was also evaluated by altering Pd and Zn composition of the Pd/ZnO/Al2O3 catalyst. Of the catalysts and conditions tested, selectivity toward liquid hydrocarbon was highest when using a 5% Pd metal loading and Pd/Zn molar ratio of 0.25 and mixed with HZMS-5, operating at 310oC and 300 psig, CO conversion was 43 % and selectivity (carbon weight basis) to hydrocarbons was 49 wt. %. Of the hydrocarbon fraction, 44wt. % was in the C5-C12 liquid product range and consisted primarily of aromatic

Synthesis and Characterization of Quaternary Metal Chalcogenide Aerogels for Gas Separation and Volatile Hydrocarbon Adsorption

KAUST Repository

Edhaim, Fatimah A.

2017-11-01

In this dissertation, the metathesis route of metal chalcogenide aerogel synthesis was expanded by conducting systematic studies between polysulfide building blocks and the 1st-row transition metal linkers. Resulting materials were screened as sorbents for selective gas separation and volatile organic compounds adsorption. They showed preferential adsorption of polarizable gases (CO2) and organic compounds (toluene). Ion exchange and heavy metal remediation properties have also been demonstrated. The effect of the presence of different counter-ion within chalcogel frameworks on the adsorption capacity of the chalcogels was studied on AFe3Zn3S17 (A= K, Na, and Rb) chalcogels. The highest adsorption capacity toward hydrocarbons and gases was observed on Rb based chalcogels. Adopting a new building block [BiTe3]3- with the 1st-row transition metal ions results in the formation of three high BET surface area chalcogels, KCrBiTe3, KZnBiTe3, and KFeBiTe3. The resulting chalcogels showed preferential adsorption of toluene vapor, and remarkable selectivity of CO2, indicating the potential future use of chalcogels in adsorption-based gas or hydrocarbon separation processes. The synthesis and characterization of the rare earth chalcogels NaYSnS4, NaGdSnS4, and NaTbSnS4 are also reported. Rare earth metal ions react with the thiostannate clusters in formamide solution forming extended polymeric networks by gelation. Obtained chalcogels have high BET surface areas, and showed notable adsorption capacity toward CO2 and toluene vapor. These chalcogels have also been engaged in the absorption of different organic molecules. The results reveal the ability of the chalcogels to distinguish among organic molecules on their electronic structures; hence, they could be used as sensors. Furthermore, the synthesis of metal chalcogenide aerogels Co0.5Sb0.33MoS4 and Co0.5Y0.33MoS4 by the sol-gel method is reported. In this system, the building blocks [MoS4]2- chelated with Co2+ and (Sb3

High-gravity combustion synthesis and in situ melt infiltration: A new method for preparing cemented carbides

International Nuclear Information System (INIS)

Liu, Guanghua; Li, Jiangtao; Yang, Zengchao; Guo, Shibin; Chen, Yixiang

2013-01-01

A new method of high-gravity combustion synthesis and in situ melt infiltration is reported for preparing cemented carbides, where hot nickel melt is in situ synthesized from a highly exothermic combustion reaction and then infiltrated into tungsten carbide powder compacts. The as-prepared sample showed a homogeneous microstructure, and its relative density, hardness and flexural strength were 94.4%, 84 HRA and 1.49 GPa, respectively. Compared with conventional powder metallurgy approaches, high-gravity combustion synthesis offers a fast and furnace-free way to produce cemented carbides

Sample preparation of environmental samples using benzene synthesis followed by high-performance LSC

International Nuclear Information System (INIS)

Filippis, S. De; Noakes, J.E.

1991-01-01

Liquid scintillation counting (LSC) techniques have been widely employed as the detection method for determining environmental levels of tritium and 14 C. Since anthropogenic and nonanthropogenic inputs to the environment are a concern, sampling the environment surrounding a nuclear power facility or fuel reprocessing operation requires the collection of many different sample types, including agriculture products, water, biota, aquatic life, soil, and vegetation. These sample types are not suitable for the direct detection of tritium of 14 C for liquid scintillation techniques. Each sample type must be initially prepared in order to obtain the carbon or hydrogen component of interest and present this in a chemical form that is compatible with common chemicals used in scintillation counting applications. Converting the sample of interest to chemically pure benzene as a sample preparation technique has been widely accepted for processing samples for radiocarbon age-dating applications. The synthesized benzene is composed of the carbon or hydrogen atoms from the original sample and is ideal as a solvent for LSC with excellent photo-optical properties. Benzene synthesis followed by low-background scintillation counting can be applied to the preparation and measurement of environmental samples yielding good detection sensitivities, high radionuclide counting efficiency, and shorter preparation time. The method of benzene synthesis provides a unique approach to the preparation of a wide variety of environmental sample types using similar chemistry for all samples

Solvothermal synthesis: a new route for preparing nitrides

CERN Document Server

Demazeau, G; Denis, A; Largeteau, A

2002-01-01

Solvothermal synthesis appears to be an interesting route for preparing nitrides such as gallium nitride and aluminium nitride, using ammonia as solvent. A nitriding additive is used to perform the reaction and, in the case of gallium nitride, is encapsulated by melt gallium. The syntheses are performed in the temperature range 400-800 deg. C and in the pressure range 100-200 MPa. The synthesized powders are characterized by x-ray diffraction and scanning electron microscopy. Finely divided gallium nitride GaN and aluminium nitride AlN, both with wurtzite-type structure, can be obtained by this route.

Nestmate recognition in social insects and the role of hydrocarbons

DEFF Research Database (Denmark)

van Zweden, Jelle Stijn; D'Ettorre, Patrizia

2010-01-01

A unique and critical analysis of the wealth of research conducted on the biology, biochemistry and chemical ecology of the rapidly growing field of insect cuticular hydrocarbons. Authored by leading experts in their respective fields, the twenty chapters show the complexity that has been...... discovered in the nature and role of hydrocarbons in entomology. Covers, in great depth, aspects of chemistry (structures, qualitative and quantitative analysis), biochemistry (biosynthesis, molecular biology, genetics, evolution), physiology, taxonomy, and ecology. Clearly presents to the reader the array...... of data, ideas, insights and historical disagreements that have been accumulated during the past half century. An emphasis is placed on the role of insect hydrocarbons in chemical communication, especially among the social insects. Includes the first review on the chemical synthesis of insect hydrocarbons...

The first preparative solution phase synthesis of melanotan II

Directory of Open Access Journals (Sweden)

2008-10-01

Full Text Available Melanotan II is a synthetic cyclic heptapeptide used to prevent a sunlight-induced skin cancer by stimulating the skin tanning process. In this paper we report the first solution phase synthesis of the title compound. The hexapeptide sequence has been assembled by [(2+2+1+1] scheme. After removing the orthogonal protection, a carbodiimide mediated lactamization, involving the ε-amino group of lysine and γ-carboxy group of aspartic acid, led to a cyclic intermediate. Appending N-acetylnorleucine concluded the assembly of melanotan II molecule. Protection of the lateral groups in arginine and tryptophan was omitted for atom and step economy reasons. The total synthesis of melanotan II was accomplished in 12 steps with 2.6% overall yield, affording >90% pure peptide without using preparative chromatography.

Enabling the synthesis of medium chain alkanes and 1-alkenes in yeast

DEFF Research Database (Denmark)

Zhu, Zhiwei; Zhou, Yongjin J.; Kang, Min Kyoung

2017-01-01

Microbial synthesis of medium chain aliphatic hydrocarbons, attractive drop-in molecules to gasoline and jet fuels, is a promising way to reduce our reliance on petroleum-based fuels. In this study, we enabled the synthesis of straight chain hydrocarbons (C7–C13) by yeast Saccharomyces cerevisiae...

Seawater-cultured Botryococcus braunii for efficient hydrocarbon extraction.

Directory of Open Access Journals (Sweden)

Kenichi Furuhashi

Full Text Available As a potential source of biofuel, the green colonial microalga Botryococcus braunii produces large amounts of hydrocarbons that are accumulated in the extracellular matrix. Generally, pretreatment such as drying or heating of wet algae is needed for sufficient recoveries of hydrocarbons from B. braunii using organic solvents. In this study, the Showa strain of B. braunii was cultured in media derived from the modified Chu13 medium by supplying artificial seawater, natural seawater, or NaCl. After a certain period of culture in the media with an osmotic pressure corresponding to 1/4-seawater, hydrocarbon recovery rates exceeding 90% were obtained by simply mixing intact wet algae with n-hexane without any pretreatments and the results using the present culture conditions indicate the potential for hydrocarbon milking.Seawater was used for efficient hydrocarbon extraction from Botryococcus braunii. The alga was cultured in media prepared with seawater or NaCl. Hydrocarbon recovery rate exceeding 90% was obtained without any pretreatment.

Tritium labelled steroids, preparation process and application to synthesis of tritium labelled estrane derivatives

International Nuclear Information System (INIS)

1978-01-01

Process for preparing new steroids labelled with tritium in 6.7 and comprising in 3 a blocked ketonic group as ketal, thioketal or derivatives. Application of these products to the synthesis of tritium labelled estrane derivatives [fr

Fischer-Tropsch synthesis : catalysts and chemistry

NARCIS (Netherlands)

Loosdrecht, van de J.; Botes, F.G.; Ciobica, I.M.; Ferreira, A.C.; Gibson, P.; Moodley, D.J.; Saib, A.M.; Visagie, J.L.; Weststrate, C.J.; Niemantsverdriet, J.W.; Reedijk, J.; Poeppelmeier, K.

2013-01-01

The Fischer–Tropsch synthesis represents a time-tested and fully proven technology for the conversion of synthesis gas (CO + H2) into paraffins, olefins, and oxygenated hydrocarbons. Depending on the origin of the syngas, one speaks of gas-to-liquids, coal-to-liquids, biomass-to-liquids, or

Characterization structural and morphology ZSM-5 zeolite by hydrothermal synthesis

International Nuclear Information System (INIS)

Silva, V.J.; Crispim, A.C.; Queiroz, M.B.; Laborde, H.M.; Rodrigues, M.G.F.; Menezes, R.R.

2009-01-01

Solid acids are catalytic materials commonly used in the chemical industry. Among these zeolites are the most important business processes including water treatment, gas separation, and cracking long hydrocarbon chains to produce high octane gasoline. Its synthesis, characterization and applications have been widely studied. The objective this study was to synthesize the ZSM-5 zeolite for future use in separation processes and catalysis. The zeolite ZSM-5 was prepared by hydrothermal synthesis at 170°C, using silica, deionized water and the director of structures (TPABr - tetrapropylammonium bromide). The materials were characterized by X ray diffraction (XRD), scanning electron microscopy (SEM) and semiquantitative chemical analysis by X ray fluorescence (XRF). According to the XRD was possible to observe the formation of ZSM-5 zeolite, with peaks intense and well defined. The SEM showed the formation of individual particles, clean, rounded shapes. (author)

Novel synthesis strategy for the preparation of individual phytosterol oxides.

Science.gov (United States)

Gao, Junlan; Yue, Qiulin; Ji, Yishun; Cheng, Beijiu; Zhang, Xin

2013-01-30

Sterols (cholesterol and phytosterols) are important structural components of cell membranes and major constituents of lipid metabolism. Research on their oxides, such as the factors affecting oxidation, oxides' structures, and qualitative and quantitative analysis, aroused more attention in this decade. However, the biological roles of individual phytosterol oxides are still unclear because no commercial individual phytosterol oxide standards are available. Different from the traditional chemical synthesis, in the present study, chemical synthesis from a starting phytosterol mixture followed with a semipreparative HPLC separation produced individual oxides. TLC and analytical HPLC were used here to not only monitor the reaction process but also specifically analyze the synthetic intermediates and oxides. The chromatographic results exhibited strict rules and similar characteristics. Finally, for the first time, four individual phytosterol oxides were successfully separated and collected by a semipreparative HPLC system, thus providing a novel strategy for the preparation of individual phytosterol oxides.

Enantioselective Synthesis of Various Cyanohydrins Using Covalently Immobilized Preparations of Hydroxynitrile Lyase from Prunus dulcis.

Science.gov (United States)

Alagöz, Dilek; Tükel, S Seyhan; Yildirim, Deniz

2015-11-01

The carrier-based and carrier-free (cross-linked enzyme aggregate) covalent immobilizations of Prunus dulcis hydroxynitrile lyase were investigated. The immobilized preparations were tested for enantioselective carbon-carbon bond formation activity in the biphasic medium. Of the tested preparations, only cross-linked enzyme aggregate of P. dulcis hydroxynitrile lyase (PdHNL-CLEA) achieved the synthesis of (R)-mandelonitrile with 93% yield and 99% enantiopurity. PdHNL-CLEA was also used in the synthesis of various (R)-cyanohydrins from corresponding aldehydes/ketones and hydrocyanic acid. When 4-methoxybenzaldehyde, 4-methyl benzaldehyde, and 4-hydroxybenzaldehyde were used as substrates, the yield-enantiomeric excess of corresponding (R)-cyanohydrins were obtained as 95-95, 85-79, and 2-25%, respectively, after 96 h at pH 4.0 and 5 °C. For acetophenone, 4-fluoroacetophenone, 4-chloroacetophenone, 4-bromoacetophenone, and 4-iodoacetophenone, the yield-enantiomeric excess of corresponding (R)-cyanohydrins were 1-99, 20-84, 11-95, 5-99, and 3-24%, respectively at the same conditions. The results demonstrate PdHNL-CLEA can be effectively used in the synthesis of (R)-mandelonitrile.

Mechanistic studies related to the metal catalyzed reduction of carbon monoxide to hydrocarbons. Final report, April 1, 1977-June 30, 1985

International Nuclear Information System (INIS)

Casey, C.P.

1985-02-01

Studies of compounds related to proposed intermediates in the hydrogenation of carbon monoxide over homogeneous and heterogeneous catalysts have been carried out. The synthesis, structure, and reactions of metal formyl compounds have been investigated. The synthesis and desproportionation reactions of hydroxymethyl metal compounds have been explored. Reactions involving interconversion of n 5 - and n'-C 5 H 5 organometallic compounds have been discovered. New synthetic routes to bimetallic compounds with bridging hydrocarbon ligands have been developed. The first bimetallic compound with a budging CH ligand has been prepared. The hydrocarbation reaction in which the CH bond of a bridging methylidyne complex adds across a carbon-carbon double bond has been discovered. New heterobimetallic compounds linked by a heterodifunctional ligand and heterobimetallic compounds with directly bonded early and late transition metals have been synthesized in a search for new CO hydrogenation catalysts. 36 refs

Progress of studies on preparation of TiO2 photocatalysts with sol-gel auto igniting synthesis

Science.gov (United States)

Wu, Di; Shi, Zaifeng; Zhang, Xiaopeng; Xinghui, Wu

2017-11-01

In this article, influencing factors on the kinetics of the process of Sol-gel Auto igniting Synthesis (SAS) which is an advanced technology for preparing nanometer particles of inorganic materials were reviewed. The studies on preparing of nanometer TiO2 photocatalysts with SAS were focused. It was concluded that SAS will play an important role in practical preparing of high-pure nanometer TiO2 powder, and as a technical support, preparation of titania TiO2 from titanic iron ore with SAS is feasible and practicable.

Synthesis and structural characteristics of polycyclic aromatic hydrocarbon-containing phenol formaldehyde resites

Energy Technology Data Exchange (ETDEWEB)

Sirkecioglu, O.; Andresen, J.M.; McRae, C.; Snape, C.E. [University of Strathclyde, Glasgow (United Kingdom). Dept. of Pure and Applied Chemistry

1997-10-24

Nonsoftening phenol-formaldehyde (PF) co-resites can be used to probe the formation of polycyclic aromatic hydrocarbons (PAHs) during the carbonization, gasification, and liquefaction of coals and other solids fuels as they facilitate the incorporation of individual PAHs into a highly crosslinked matrix. A series of PAH and diphenylalkane-containing phenolic co-resites were prepared using phenol, with, as the second component, 2-naphthol, 4-hydroxy 9-diphenylmethane, 4, 4`-dihydroxydiphenylethane, 1-4(4-hydroxybenzyl)naphthalene, 9-(4-hydroxybenzyl) anthracene, and 9-(4-hydroxybenzyl) phenanthrene. A mole ratio of 3:1 (phenol:second phenolic constituent) was used. The virtually complete elimination of ether and methyl functions from the resoles by curing at 200{degree}C was monitored by solid-state {sup 13}C-NMR. The resites were also characterized by Fourier transform infrared spectroscopy. The volatile-matter contents of the PAH-containing resites were all higher than that of the normal resite. The carbonization of the 9-(4-hydroxybenzyl) anthracene-containing resite in a fluidized-bed reactor is used to illustrate the potential applications of the PAH-containing resites in fuel science.

Electrochemical Study of Hydrocarbon-Derived Electrolytes for Supercapacitors

Science.gov (United States)

Noorden, Zulkarnain A.; Matsumoto, Satoshi

2013-10-01

In this paper, we evaluate the essential electrochemical properties - capacitive and resistive behaviors - of hydrocarbon-derived electrolytes for supercapacitor application using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The electrolytes were systematically prepared from three hydrocarbon-derived compounds, which have different molecular structures and functional groups, by treatment with high-concentration sulfuric acid (H2SO4) at room temperature. Two-electrode cells were assembled by sandwiching an electrolyte-containing glass wool separator with two active electrodes of activated carbon sheets. The dc electrical properties of the tested cells in terms of their capacitive behavior were investigated by CV, and in order to observe the frequency characteristics of the constructed cells, EIS was carried out. Compared with the tested cell with only high-concentration H2SO4 as the electrolyte, the cell with the derived electrolytes exhibit a capacitance as high as 135 F/g with an improved overall internal resistance of 2.5 Ω. Through the use of a simple preparation method and low-cost precursors, hydrocarbon-derived electrolytes could potentially find large-scale and higher-rating supercapacitor applications.

Biosyngas Fischer. Tropsch conversion by high Fe loaded supported catalysts prepared with ultrasound and microwave

Energy Technology Data Exchange (ETDEWEB)

Pirola, C.; Di Fronzo, A.; Boffito, D.C.; Bianchi, C. [Milano Univ. (Italy). Dipt. di Chimica; Di Michele, A. [Perugia Univ. (Italy). Dipt. di Fisica

2012-07-01

Catalysts with iron high loading of 30 wt%, promoted with K (2.0 wt%) and Cu (3.75 wt%), have been synthesized according to three different methods: (1) the traditional impregnation method (TR); (2) Ultrasound (US) assisted TR method; (3) Microwave (MW) assisted TR method. All the samples have been fully characterized by BET, ICP/OES, XRPD, TG-DTA, FT-IR, TPR, SEM and TEM and tested in a laboratory pilot plant for Fischer-Tropsch synthesis working at 220 C and 20 bar. The results of the catalysts characterization indicated that the morphology of the samples strongly depends on the method of preparation. The best FTS results in term of C{sub 2+} yield (41%) has been obtained using MW with a good value of the selectivity towards heavy hydrocarbons, while in term of CO conversion (58%), using US. The samples prepared with non-traditional methods show FTS better results, probably due to a more wide and uniform distribution of Fe in the medium during the synthesis phase. (orig.)

Fast synthesis of the polycrystalline materials on the base of Zn 3 V2 MoO11 and Zn 2.5 VMoO8

Directory of Open Access Journals (Sweden)

Maya Markova-Velichkova

2009-12-01

Full Text Available In our study we applied two different techniques for the preparation of Zn3V2MoO11 and Zn2.5VMoO8 polycrystalline materials - melt quenching method (up-bottom and mechanochemical synthesis (bottom- up. These compounds belong to the family of materials with general formula M2.5VMoO8 (M=Zn, Mg, Mn, Co. They are potential candidates as catalysts in processes of selective oxidation of hydrocarbons. Until now, these two compounds were obtained by conventional solid state reaction. Using infrared spectroscopy and X-ray diffraction we proved that the melt quenching technique is a quite appropriate method for the synthesis of bulk Zn3V2-MoO11 phase. Mechanochemical activation is more appropriated for the preparation of nonosized Zn2.5VMoO8 powder. It was established that the melt quenching technique and mechanochemical activation are faster in comparison with conventional ceramic methods for the given synthesis.

Mobile geophysics for searching and exploration of Domanic hydrocarbon deposits

Science.gov (United States)

Borovsky, M. Ya; Uspensky, B. V.; Valeeva, S. E.; Borisov, A. S.

2018-05-01

There are noted features of shale hydrocarbons occurrence. It is shown the role of geophysical prospecting in the geological prospecting process for non-traditional sources of hydrocarbon. There are considered the possibilities of non-seismic methods for forecasting, prospecting, exploration and preparation of Domanikovian hydrocarbons accumulations for exploration. It is emphasized the need for geophysical studies of tectonic disturbances. Modern aerogeophysical instrumentation and methodological support allows to combine high-precision magneto-prospecting with gravimetric and gamma spectrometry. This combination of geophysical methods contributes to the diagnosis of active and latent faults.

Wet milling versus co-precipitation in magnetite ferrofluid preparation

Directory of Open Access Journals (Sweden)

Almásy László

2015-01-01

Full Text Available Various uses of ferrofluids for technical applications continuously raise the interest in improvement and optimization of preparation methods. This paper deals with preparation of finely granulated magnetite particles coated with oleic acid in hydrocarbon suspensions following either chemical co-precipitation from iron salt precursors or wet milling of micron size magnetite powder with the goal to compare the benefits and disadvantages of each method. Microstructural measurements showed that both methods gave similar magnetite particle size of 10-15 nm. Higher saturation magnetization was achieved for the wet-milled magnetite suspension compared to relatively rapid co-precipitation synthesis. Different efficacies of ferrophase incorporation into kerosene could be related to the different mechanisms of oleic acid bonding to nanoparticle surface. The comparative data show that wet milling represents a practicable alternative to the traditional co-precipitation since despite of longer processing time, chemicals impact on environment can be avoided as well as the remnant water in the final product.

Production of hydrogen from hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Lohmueller, R

1984-03-01

Hydrocarbons are the preferred starting materials for the industrial production of hydrogen. Most hydrogen is produced by steam reforming of light hydrocarbons. Partial oxidation of heavy oil and residue is used for the production of H/sub 2/ and synthesis gas in large plants. In both cases gas purification was improved. Hydrogen-rich gases like coke oven gas, refinery-offgas, and offgases from the chemical and petrochemical industry have high potential for becoming a major source of hydrogen. Processes for recovering H/sub 2/ (and by-products) are condensation and rectification at low temperatures and, most attractive and versatile for the production of very pure H/sub 2/, adsorption (PSA). The environmental impact of H/sub 2/ production lies mainly in the emission of CO/sub 2/ and heat. Other forms of pollution can be considerably reduced by conventional methods. The economy of H/sub 2/ production depends essentially on price and availability of the raw materials.

Lobatamide C: total synthesis, stereochemical assignment, preparation of simplified analogues, and V-ATPase inhibition studies.

Science.gov (United States)

Shen, Ruichao; Lin, Cheng Ting; Bowman, Emma Jean; Bowman, Barry J; Porco, John A

2003-07-02

The total synthesis and stereochemical assignment of the potent antitumor macrolide lobatamide C, as well as synthesis of simplified lobatamide analogues, is reported. Cu(I)-mediated enamide formation methodology has been developed to prepare the highly unsaturated enamide side chain of the natural product and analogues. A key fragment coupling employs base-mediated esterification of a beta-hydroxy acid and a salicylate cyanomethyl ester. Three additional stereoisomers of lobatamide C have been prepared using related synthetic routes. The stereochemistry at C8, C11, and C15 of lobatamide C was assigned by comparison of stereoisomers and X-ray analysis of a crystalline derivative. Synthetic lobatamide C, stereoisomers, and simplified analogues have been evaluated for inhibition of bovine chromaffin granule membrane V-ATPase. The salicylate phenol, enamide NH, and ortho-substitution of the salicylate ester have been shown to be important for V-ATPase inhibitory activity.

Synthesis of g-C3N4/Fe3O4 nanocomposites and application as a new sorbent for solid phase extraction of polycyclic aromatic hydrocarbons in water samples.

Science.gov (United States)

Wang, Man; Cui, Shihai; Yang, Xiaodi; Bi, Wentao

2015-01-01

An easy preparation of g-C3N4/Fe3O4 nanocomposites by chemical co-precipitation has been demonstrated. The as-prepared materials were characterized by X-ray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy and thermogravimetric analysis. The high affinity of g-C3N4 toward polycyclic aromatic hydrocarbons and the magnetic behavior of Fe3O4 were combined to provide an efficient and simple magnetic solid phase extraction (MSPE). The adsorption and desorption of polycyclic aromatic hydrocarbons on g-C3N4/Fe3O4 were examined. Different factors affecting the magnetic solid phase extraction of polycyclic aromatic hydrocarbons were assessed in terms of adsorption, desorption, and recovery. Under the optimized conditions, the proposed method showed good limits of detection (LOD, S/N=3) in the range of 0.05-0.1 ng mL(-1) and precision in the range of 1.8-5.3% (RSDs, n=3). This method was also successfully applied to the analysis of real water samples; good spiked recoveries over the range of 80.0-99.8% were obtained. Copyright © 2014 Elsevier B.V. All rights reserved.

Method of Generating Hydrocarbon Reagents from Diesel, Natural Gas and Other Logistical Fuels

Science.gov (United States)

Herling, Darrell R [Richland, WA; Aardahl, Chris L [Richland, WA; Rozmiarek, Robert T [Middleton, WI; Rappe, Kenneth G [Richland, WA; Wang, Yong [Richland, WA; Holladay, Jamelyn D [Kennewick, WA

2008-10-14

The present invention provides a process for producing reagents for a chemical reaction by introducing a fuel containing hydrocarbons into a flash distillation process wherein the fuel is separated into a first component having a lower average molecular weight and a second component having a higher average molecular weight. The first component is then reformed to produce synthesis gas wherein the synthesis gas is reacted catalytically to produce the desire reagent.

A Simple and Rapid Method for Preparing a Cell-Free Bacterial Lysate for Protein Synthesis.

Directory of Open Access Journals (Sweden)

Nitzan Krinsky

Full Text Available Cell-free protein synthesis (CFPS systems are important laboratory tools that are used for various synthetic biology applications. Here, we present a simple and inexpensive laboratory-scale method for preparing a CFPS system from E. coli. The procedure uses basic lab equipment, a minimal set of reagents, and requires less than one hour to process the bacterial cell mass into a functional S30-T7 extract. BL21(DE3 and MRE600 E. coli strains were used to prepare the S30-T7 extract. The CFPS system was used to produce a set of fluorescent and therapeutic proteins of different molecular weights (up to 66 kDa. This system was able to produce 40-150 μg-protein/ml, with variations depending on the plasmid type, expressed protein and E. coli strain. Interestingly, the BL21-based CFPS exhibited stability and increased activity at 40 and 45°C. To the best of our knowledge, this is the most rapid and affordable lab-scale protocol for preparing a cell-free protein synthesis system, with high thermal stability and efficacy in producing therapeutic proteins.

A Simple and Rapid Method for Preparing a Cell-Free Bacterial Lysate for Protein Synthesis

Science.gov (United States)

Kaduri, Maya; Shainsky-Roitman, Janna; Goldfeder, Mor; Ivanir, Eran; Benhar, Itai; Shoham, Yuval; Schroeder, Avi

2016-01-01

Cell-free protein synthesis (CFPS) systems are important laboratory tools that are used for various synthetic biology applications. Here, we present a simple and inexpensive laboratory-scale method for preparing a CFPS system from E. coli. The procedure uses basic lab equipment, a minimal set of reagents, and requires less than one hour to process the bacterial cell mass into a functional S30-T7 extract. BL21(DE3) and MRE600 E. coli strains were used to prepare the S30-T7 extract. The CFPS system was used to produce a set of fluorescent and therapeutic proteins of different molecular weights (up to 66 kDa). This system was able to produce 40–150 μg-protein/ml, with variations depending on the plasmid type, expressed protein and E. coli strain. Interestingly, the BL21-based CFPS exhibited stability and increased activity at 40 and 45°C. To the best of our knowledge, this is the most rapid and affordable lab-scale protocol for preparing a cell-free protein synthesis system, with high thermal stability and efficacy in producing therapeutic proteins. PMID:27768741

HYDROCARBON FORMATION ON POLYMER-SUPPORTED COBALT

Energy Technology Data Exchange (ETDEWEB)

Benner, Linda S.; Perkins, Patrick; Vollhardt, K.Peter C.

1980-10-01

In this report we detail the synthesis catalytic chemistry of polystyrene supported {eta}{sup 5} ~cyclopentadienyl- dicarbonyl cobalt, CpCo(CO){sub 2}. This material is active in the hydrogenation of CO to saturated linear hydrocarbons and appears to retain its "homogeneous", mononuclear character during the course of its catalysis, During ·the course of our work 18% and 20% crosslinked analogs of polystyrene supported CpCo(CO){sub 2} were shown to exhibit limited catalytic activity and no CO activation.

Bismuth molybdate catalysts prepared by mild hydrothermal synthesis: Influence of pH on the selective oxidation of propylene

DEFF Research Database (Denmark)

Schuh, Kirsten; Kleist, Wolfgang; Høj, Martin

2015-01-01

A series of bismuth molybdate catalysts with relatively high surface area was prepared via mild hydrothermal synthesis. Variation of the pH value and Bi/Mo ratio during the synthesis allowed tuning of the crystalline Bi-Mo oxide phases, as determined by X-ray diffraction (XRD) and Raman...... spectroscopy. The pH value during synthesis had a strong influence on the catalytic performance. Synthesis using a Bi/Mo ratio of 1/1 at pH ≥ 6 resulted in γ-Bi2MoO6, which exhibited a better catalytic performance than phase mixtures obtained at lower pH values. However, a significantly lower catalytic...

Aspects of 6-[18F]fluoro-L-DOPA preparation: precursor synthesis, preparative HPLC purification and determination of radiochemical purity

International Nuclear Information System (INIS)

Fuechtner, F.; Angelberger, P.; Kvaternik, H.; Hammerschmidt, F.; Simovc, B. Peric; Steinbach, J.

2002-01-01

A modified method for the synthesis of the intermediate product N-Boc-3,4-di(Boc-O)-6-iodo-L-phenylalanine ethyl ester of the [ 18 F]FDOPA precursor preparation was developed. With the application of bis-(trifluoroacetoxy)-iodobenzene for the iodination step with elemental iodine the yield of the intermediate can be increased from 12% to 50-60%. By replacing silica-gel-based RP HPLC column by a polymer-based column for semi-preparative purification of [ 18 F]FDOPA from the reaction mixture the radiochemical purity of the final product can be increased up to >99%. For the determination of the radiochemical impurity [ 18 F]fluoride a HPLC method using a column with polymer-based RP material was introduced

Controlled soft-template synthesis of ultrathin C@FeS nanosheets with high-Li-storage performance.

Science.gov (United States)

Xu, Chen; Zeng, Yi; Rui, Xianhong; Xiao, Ni; Zhu, Jixin; Zhang, Wenyu; Chen, Jing; Liu, Weiling; Tan, Huiteng; Hng, Huey Hoon; Yan, Qingyu

2012-06-26

We report a facile approach to prepare carbon-coated troilite FeS (C@FeS) nanosheets via surfactant-assisted solution-based synthesis. 1-Dodecanethiol is used as both the sulfur source and the surfactant, which may form different-shaped micelles to direct the growth of nanostructures. Under appropriate growth conditions, the iron and sulfur atoms react to form thin layers of FeS while the hydrocarbon tails of 1-dodecanethiol separate the thin FeS layers, which turn to carbon after annealing in Ar. Such an approach can be extended to grow C@FeS nanospheres and nanoplates by modifying the synthesis parameters. The C@FeS nanosheets display excellent Li storage properties with high specific capacities and stable charge/discharge cyclability, especially at fast charge/discharge rates.

The ortho backbone amide linker (o-BAL) is an easily prepared and highly acid-labile handle for solid-phase synthesis

DEFF Research Database (Denmark)

Boas, Ulrik; Brask, Jesper; Christensen, J.B.

2002-01-01

The tris(alkoxy)benzyl backbone amide linker (BAL) has found widespread application in solid-phase synthesis. The key intermediate for preparation of para BAL (p-BAL) is 2,6-dimethoxy-4-hydroxybenzaldehyde; several reports on its synthesis have appeared. However, the ortho analogue of the handle (o...

Method and apparatus for producing synthesis gas

Science.gov (United States)

Hemmings, John William; Bonnell, Leo; Robinson, Earl T.

2010-03-03

A method and apparatus for reacting a hydrocarbon containing feed stream by steam methane reforming reactions to form a synthesis gas. The hydrocarbon containing feed is reacted within a reactor having stages in which the final stage from which a synthesis gas is discharged incorporates expensive high temperature materials such as oxide dispersed strengthened metals while upstream stages operate at a lower temperature allowing the use of more conventional high temperature alloys. Each of the reactor stages incorporate reactor elements having one or more separation zones to separate oxygen from an oxygen containing feed to support combustion of a fuel within adjacent combustion zones, thereby to generate heat to support the endothermic steam methane reforming reactions.

A short synthesis and its application to the preparation of radio labelled leukotriene inhibitor Sch 37224

International Nuclear Information System (INIS)

Duelfer, T.; Gala, D.

1991-01-01

A new, short synthesis of 1-(1,2-dihydro-4-hydroxyl-1-phenyl-2-oxo-1,8-naphthyridin-3-yl)-pyrrolidinium hydroxide, inner salt, 1, was achieved by condensing methyl 2-phenylamino-3-pyridine carboxylate 2 with ethyl 1-pyrrolidine acetate 4. This gave highly pure product in 60% yield. This synthesis was applied to the preparation of 14 C labelled 1. Radiolabelled 1 was synthesized from u-[ 14 C]-aniline in three steps at 97% radiochemical purity and 27.3% radiochemical yield. (author)

Bi-reforming of methane from any source with steam and carbon dioxide exclusively to metgas (CO-2H2) for methanol and hydrocarbon synthesis.

Science.gov (United States)

Olah, George A; Goeppert, Alain; Czaun, Miklos; Prakash, G K Surya

2013-01-16

A catalyst based on nickel oxide on magnesium oxide (NiO/MgO) thermally activated under hydrogen is effective for the bi-reforming with steam and CO(2) (combined steam and dry reforming) of methane as well as natural gas in a tubular flow reactor at elevated pressures (5-30 atm) and temperatures (800-950 °C). By adjusting the CO(2)-to-steam ratio in the gas feed, the H(2)/CO ratio in the produced syn-gas could be easily adjusted in a single step to the desired value of 2 for methanol and hydrocarbon synthesis.

Ammonia sensing properties of V-doped ZnO:Ca nanopowders prepared by sol–gel synthesis

International Nuclear Information System (INIS)

Fazio, E.; Hjiri, M.; Dhahri, R.; El Mir, L.; Sabatino, G.; Barreca, F.; Neri, F.; Leonardi, S.G.; Pistone, A.; Neri, G.

2015-01-01

V-doped ZnO:Ca nanopowders with different V loading were prepared by sol–gel synthesis and successive drying in ethanol under supercritical conditions. Characterization data of nanopowders annealed at 700 °C in air, revealed that they have the wurtzite structure. Raman features of V-doped ZnO:Ca samples were found to be substantially modified with respect to pure ZnO or binary ZnO:Ca samples, which indicate the substitution of vanadium ions in the ZnO lattice. The ammonia sensing properties of V-doped ZnO:Ca thick films were also investigated. The results obtained demonstrate the possibility of a fine tuning of the sensing characteristics of ZnO-based sensors by Ca and V doping. In particular, their combined effect has brought to an enhanced response towards NH 3 compared to bare ZnO and binary V-ZnO and Ca-ZnO samples. Raman investigation suggested that the presence of Ca play a key role in enhancing the sensor response in these ternary composite nanomaterials. - Graphical abstract: V-doped ZnO:Ca nanopowders prepared by sol–gel synthesis possess enhanced sensing characteristics towards NH 3 compared to bare ZnO. - Highlights: • V-doped ZnO:Ca nanopowders with different V loading were prepared by sol–gel synthesis. • Raman features of V-doped ZnO:Ca samples indicate the substitution of V ions in the ZnO lattice. • Combined effects of dopants have brought to an enhanced response to NH 3 compared to ZnO. • Ca play a key role in enhancing the sensor response of ternary V-doped ZnO:Ca composites

High-Quality ZnCdS Nanosheets Prepared Using Solvothermal Synthesis

International Nuclear Information System (INIS)

Mahdi, M.A.; Hassan, J.J.; Ng, S.S.; Hassan, Z.

2013-01-01

For the first time, Zn X Cd 1-X S nanosheets with different Zn and Cd ion concentrations were prepared using solvothermal synthesis at 200 degree C for 4 and 24 h. The crystalline structure of the nanosheets was wurtzite. The optical band gaps of the nanosheets increased with increasing Zn ratio; this increase is consistent with the band gaps estimated using Vegard’s formula. The photoluminescence spectra for the 24 h nanosheets had higher emission intensities than those for the 4 h nanosheets. The emission band corresponding to intrinsic near-band-edge emission and a broad peak associated with extrinsic deep-level emission were observed in the photoluminescence spectra.

Fiscal 1996 international research cooperation project. Feasibility study of finding out the seeds of international joint research (technology for effective use of saturated hydrocarbon, technology for reducing excess of aromatic hydrocarbon, high-grade treatment technology of petroleum coke); 1996 nendo kokusai kenkyu kyoryoku jigyo. Kokusai kyodo kenkyu seeds hakkutsu no tame no FS chosa (howa tanka suiso no yuko riyo gijutsu, hokozoku tanka suiso no yojo taisaku gijutsu, sekiyu cokes no kodo shori gijutsu)

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-03-01

This project is aimed at internationally cooperating in the R and D of industrial technology and improving industrial technology of Japan. For it, the following three technologies were investigated: (1) technology for effective use of saturated hydrocarbon, (2) technology for reducing excess of aromatic hydrocarbon, (3) high-grade treatment technology of petroleum coke. In (1), surveys were conducted of technologies of effective use of natural gas and effective use of C4 saturated hydrocarbon. Surveyed were a method for producing synthesis gas from natural gas, a technology to liquefy natural gas into fuel following the synthesis gas production process, a technology to liquefy natural gas into fuel without the synthesis gas production process, and the trend of effective use of C4 saturated hydrocarbon. In (2), surveys were made of process to reduce production of aromatic hydrocarbon as much as possible, process to effectively separate aromatic hydrocarbon, and process to convert excess aromatic hydrocarbon into polymer, etc. In (3), surveys were conducted on petroleum coke and pitch in terms of production methods, the supply/demand situation, property characteristics, usability to new fields, etc. 170 refs., 114 figs., 65 tabs.

Ionic liquids for nano- and microstructures preparation. Part 2: Application in synthesis.

Science.gov (United States)

Łuczak, Justyna; Paszkiewicz, Marta; Krukowska, Anna; Malankowska, Anna; Zaleska-Medynska, Adriana

2016-01-01

Ionic liquids (ILs) are widely applied to prepare metal nanoparticles and 3D semiconductor microparticles. Generally, they serve as a structuring agent or reaction medium (solvent), however it was also demonstrated that ILs can play a role of a co-solvent, metal precursor, reducing as well as surface modifying agent. The crucial role and possible types of interactions between ILs and growing particles have been presented in the Part 1 of this review paper. Part 2 of the paper gives a comprehensive overview of recent experimental studies dealing with application of ionic liquids for preparation of metal and semiconductor based nano- and microparticles. A wide spectrum of preparation routes using ionic liquids is presented, including precipitation, sol-gel technique, hydrothermal method, nanocasting and ray-mediated methods (microwave, ultrasound, UV-radiation and γ-radiation). It was found that ionic liquids formed of a 1-butyl-3-methylimidazolium [BMIM] combined with tetrafluoroborate [BF4], hexafluorophosphate [PF6], and bis(trifluoromethanesulfonyl)imide [Tf2N] are the most often used ILs in the synthesis of nano- and microparticles, due to their low melting temperature, low viscosity and good transportation properties. Nevertheless, examples of other IL classes with intrinsic nanoparticles stabilizing abilities such as phosphonium and ammonium derivatives are also presented. Experimental data revealed that structure of ILs (both anion and cation type) affects the size and shape of formed metal particles, and in some cases may even determine possibility of particles formation. The nature of the metal precursor determines its affinity to polar or nonpolar domains of ionic liquid, and therefore, the size of the nanoparticles depends on the size of these regions. Ability of ionic liquids to form varied extended interactions with particle precursor as well as other compounds presented in the reaction media (water, organic solvents etc.) provides nano- and

Hydrocarbon isotope detection by elastic peak electron spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Kostanovskiy, I.A., E-mail: kostanovskiyia@gmail.com [National Research University MPEI, Krasnokazarmennaya 14, 111250 Moscow (Russian Federation); Afanas’ev, V.P. [National Research University MPEI, Krasnokazarmennaya 14, 111250 Moscow (Russian Federation); Naujoks, D. [Max-Planck-Institut für Plasmaphysik, Teilinstitut Greifswald, Wendelsteinstraße 1, D-17491 Greifswald (Germany); Mayer, M. [Max-Planck-Institut für Plasmaphysik, D-85748 Garching (Germany)

2015-07-15

Highlights: • PCVD hydrocarbon coatings containing protium or deuterium are analyzed via NRA, ERD, XPS and EPES. • EPES analysis with modern electron energy analyzer SPECS Phoibos 225 shows a clear signal from the hydrogen isotopes. • Different primary energies and scattering angles help to quantify isotope content from EPES spectra. - Abstract: Experimental results on the hydrocarbon isotope analysis by elastic peak electron spectroscopy are presented. Amorphous hydrocarbon samples (a-C:H, a-C:D) are prepared by PCVD and analyzed by nuclear reaction analysis (NRA), elastic recoil detection analysis (ERD), X-ray photoelectron spectroscopy (XPS) and elastic peak electron spectroscopy (EPES). Electron energy spectra show a clear signal from the hydrogen isotopes deuterium and protium. Different incident energies and scattering geometries help to resolve plasmon and elastic energy losses.

Hydrocarbon isotope detection by elastic peak electron spectroscopy

International Nuclear Information System (INIS)

Kostanovskiy, I.A.; Afanas’ev, V.P.; Naujoks, D.; Mayer, M.

2015-01-01

Highlights: • PCVD hydrocarbon coatings containing protium or deuterium are analyzed via NRA, ERD, XPS and EPES. • EPES analysis with modern electron energy analyzer SPECS Phoibos 225 shows a clear signal from the hydrogen isotopes. • Different primary energies and scattering angles help to quantify isotope content from EPES spectra. - Abstract: Experimental results on the hydrocarbon isotope analysis by elastic peak electron spectroscopy are presented. Amorphous hydrocarbon samples (a-C:H, a-C:D) are prepared by PCVD and analyzed by nuclear reaction analysis (NRA), elastic recoil detection analysis (ERD), X-ray photoelectron spectroscopy (XPS) and elastic peak electron spectroscopy (EPES). Electron energy spectra show a clear signal from the hydrogen isotopes deuterium and protium. Different incident energies and scattering geometries help to resolve plasmon and elastic energy losses

A Free-Radical Pathway to Hydrogenated Phenanthrene in Molecular Clouds-Low Temperature Growth of Polycyclic Aromatic Hydrocarbons.

Science.gov (United States)

Thomas, Aaron M; Lucas, Michael; Yang, Tao; Kaiser, Ralf I; Fuentes, Luis; Belisario-Lara, Daniel; Mebel, Alexander M

2017-08-05

The hydrogen-abstraction/acetylene-addition mechanism has been fundamental to unravelling the synthesis of polycyclic aromatic hydrocarbons (PAHs) detected in combustion flames and carbonaceous meteorites like Orgueil and Murchison. However, the fundamental reaction pathways accounting for the synthesis of complex PAHs, such as the tricyclic anthracene and phenanthrene along with their dihydrogenated counterparts, remain elusive to date. By investigating the hitherto unknown chemistry of the 1-naphthyl radical with 1,3-butadiene, we reveal a facile barrierless synthesis of dihydrophenanthrene adaptable to low temperatures. These aryl-type radical additions to conjugated hydrocarbons via resonantly stabilized free-radical intermediates defy conventional wisdom that PAH growth is predominantly a high-temperature phenomenon and thus may represent an overlooked path to PAHs as complex as coronene and corannulene in cold regions of the interstellar medium like in the Taurus Molecular Cloud. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Thermodynamic models to predict gas-liquid solubilities in the methanol synthesis, the methanol-higher alcohol synthesis, and the Fischer-Tropsch synthesis via gas-slurry processes

NARCIS (Netherlands)

Breman, B.B; Beenackers, A.A C M

1996-01-01

Various thermodynamic models were tested concerning their applicability to predict gas-liquid solubilities, relevant for synthesis gas conversion to methanol, higher alcohols, and hydrocarbons via gas-slurry processes. Without any parameter optimization the group contribution equation of state

Solvent-Free Synthesis of Quaternary Metal Sulfide Nanoparticles Derived from Thiourea

KAUST Repository

Bhunia, Manas Kumar; Abou-Hamad, Edy; Anjum, Dalaver H.; Gurinov, Andrei; Takanabe, Kazuhiro

2017-01-01

The synthesis of metal sulfide (MS) materials with sizes in the sub-10 nm regime often requires capping agents with long hydrocarbon chains that affect their structures and properties. Herein, this study presents a molten-state synthesis method

On possibility of preparation of catalysts for ammonia synthesis based on cyanocomplexes of some d-metals

International Nuclear Information System (INIS)

Sergeeva, A.N.; Dovgej, V.V.; Pavlenko, L.I.; Zubritskaya, D.I.; Tkachenko, Zh.I.; Okorskaya, A.P.; Lyubchenko, Yu.A.

1983-01-01

The catalytic properties of the systems prepared on the basis of coordination cyanides of iron, ruthenium, osmium, rhenium, molydenum, vanadium and other d-metals in the ammonia synthesis reaction are studied. It has been found that thermal stability of catalytic systems containing vanadium and molybdenum is considerably higher than that of the industrial sample of similar type containing aluminium. The systems prepared on the basis of hexacyanoferrates, ruthenates and osmates can be referred to low-temperature type catalysts

Development of new methods in modern selective organic synthesis: preparation of functionalized molecules with atomic precision

International Nuclear Information System (INIS)

Ananikov, V P; Khemchyan, L L; Ivanova, Yu V; Dilman, A D; Levin, V V; Bukhtiyarov, V I; Sorokin, A M; Prosvirin, I P; Romanenko, A V; Simonov, P A; Vatsadze, S Z; Medved'ko, A V; Nuriev, V N; Nenajdenko, V G; Shmatova, O I; Muzalevskiy, V M; Koptyug, I V; Kovtunov, K V; Zhivonitko, V V; Likholobov, V A

2014-01-01

The challenges of the modern society and the growing demand of high-technology sectors of industrial production bring about a new phase in the development of organic synthesis. A cutting edge of modern synthetic methods is introduction of functional groups and more complex structural units into organic molecules with unprecedented control over the course of chemical transformation. Analysis of the state-of-the-art achievements in selective organic synthesis indicates the appearance of a new trend — the synthesis of organic molecules, biologically active compounds, pharmaceutical substances and smart materials with absolute selectivity. Most advanced approaches to organic synthesis anticipated in the near future can be defined as 'atomic precision' in chemical reactions. The present review considers selective methods of organic synthesis suitable for transformation of complex functionalized molecules under mild conditions. Selected key trends in the modern organic synthesis are considered including the preparation of organofluorine compounds, catalytic cross-coupling and oxidative cross-coupling reactions, atom-economic addition reactions, methathesis processes, oxidation and reduction reactions, synthesis of heterocyclic compounds, design of new homogeneous and heterogeneous catalytic systems, application of photocatalysis, scaling up synthetic procedures to industrial level and development of new approaches to investigation of mechanisms of catalytic reactions. The bibliography includes 840 references

A kinetically blocked 1,14:11,12-dibenzopentacene: A persistent triplet diradical of a non-Kekulé polycyclic benzenoid hydrocarbon

KAUST Repository

Li, Yuan; Huang, Kuo-Wei; Sun, Zhe; Webster, Richard D.; Zeng, Zebing; Zeng, Wangdong; Chi, Chunyan; Furukawa, Ko; Wu, Jishan

2014-01-01

The synthesis of high-spin polycyclic hydrocarbons is very challenging due to their extremely high reactivity. Herein, we report the synthesis and characterization of a kinetically blocked 1,14:11,12-dibenzopentacene, DP-Mes, which represents a rare persistent triplet diradical of a non-Kekulé polycyclic benzenoid hydrocarbon. In contrast to its structural isomer 1,14:7,8-dibenzopentacene (heptazethrene) with a singlet biradical ground state, DP-Mes is a triplet diradical as confirmed by ESR and ESTN measurements and density functional theory calculations. DP-Mes also displays intermolecular antiferromagnetic spin interactions in solution at low temperature. © 2014 the Partner Organisations.

Microbial hydrocarbon degradation - bioremediation of oil spills

Energy Technology Data Exchange (ETDEWEB)

Atlas, R M [Louisville Univ., KY (United States). Dept. of Biology

1991-01-01

Bioremediation has become a major method employed in restoration of oil-polluted environments that makes use of natural microbial biodegradative activities. Bioremediation of petroleum pollutants overcomes the factors limiting rates of microbial hydrocarbon biodegradation. Often this involves using the enzymatic capabilities of the indigenous hydrocarbon-degrading microbial populations and modifying environmental factors, particularly concentrations of molecular oxygen, fixed forms of nitrogen and phosphate to achieve enhanced rates of hydrocarbon biodegradation. Biodegradation of oily sludges and bioremediation of oil-contaminated sites has been achieved by oxygen addition-e.g. by tilling soils in landfarming and by adding hydrogen peroxide or pumping oxygen into oiled aquifers along with addition of nitrogen- and phosphorous-containing fertilizers. The success of seeding oil spills with microbial preparations is ambiguous. Successful bioremediation of a major marine oil spill has been achieved based upon addition of nitrogen and phosphorus fertilizers. (author).

Determination of adducts of polycyclic aromatic hydrocarbons to DNA

International Nuclear Information System (INIS)

Bean, R.M.; Chess, E.K.; Thomas, B.L.; Mann, D.B.; Dankovic, D.A.; Franz, J.A.; Springer, D.L.

1987-01-01

Adducts to deoxyribonucleic acid (DNA), formed from metabolites of polynuclear aromatic compounds, are relatively persistent and correlate with bioresponse (carcinogenicity). Therefore, qualitative and quantitative analysis of adducts in the DNA of individuals may provide valuable information as to recent exposure to carcinogenic hydrocarbons. Further, the ability to detect adducts in a large segment of a population may have significant epidemiological significance. The current thrust of the analytical development at PNL is to isolate the DNA, liberate the adducted hydrocarbon residue from the DNA with acid hydrolysis, and prepare derivatives of the hydrolyzed species that will enhance its detection, quantitation, and characterization using gas chromatography/mass spectrometry (GC/MS). They have initiated the development of the necessary techniques using benzo[a]pyrene (B[a]P). Samples of DNA adducts of radiolabeled B[a]P have been prepared for study by reacting DNA isolated from calf thymus with benzo[a]pyrene-7,8-diol-9,10-epoxide (the ultimate carcinogenic form of B[a]P). Other DNA/B[a]P samples have been prepared by painting the skin of mice with radiolabeled B[a]P. The ability to prepare research quantities of adducts using the hepatocyte preparation method reported by Dankovic et al is a significant development to their DNA adduct analysis program

Characterization of polycyclic aromatic hydrocarbons (PAH's) present in sampled cooked food

International Nuclear Information System (INIS)

Palm Naa-Dedei, L.M.

2010-07-01

The study was conducted to determine the levels of Polycyclic Aromatic Hydrocarbons in the following traditionally prepared food: smoked and grilled Scomba japonicus, grilled meat (khebab) and bread sampled from some Ghanaian markets. By way of preparation of traditional food, some food comes into direct contact with smoke or extremely high temperature which are potential sources of Polycyclic Aromatic Hydrocarbon generation. Levels of 20 individual Polycyclic Aromatic Hydrocarbons including acenaphthene, acenaphtyelene, anthanthrene, anthracene, benz(a)anthracene, benzo(a)pyrene, benzo(b)fluoranthene, benzo(e)pyrene, benzo(ghi)perylene, benzo(j)fluoranthene, benzo(k)fluoranthene, chrysene, cyclopenta(cd)pyrene, dibenzo(ah)anthracene, fluoranthene, fluorene, indeno(1,2,3-cd)pyrene, naphthalene, phenanthrene and pyrene were determined in 11 smoked and 5 grilled fish, 4 grilled pieces of meat and 3 loaves of baked bread using gas chromatographic techniques with flame ionization detector. Benzo(a)pyrene, which is one of the few PAH for which a legal limit exists in different types of food matrices and other high molecular weight PAHs suspected to be carcinogenic have been detected in high concentrations in most samples. Bread samples gave mean polycyclic aromatic hydrocarbon concentrations of up to 20.39 μg/kg while khebab samples gave mean polycyclicaromatic hydrocarbon concentrations of up to 67.61 μg/kg. There was positive correlation of 0.987 between levels of polycyclic aromatic hydrocarbon concentrations in khebab samples from locations Osu and Atomic down. There was a positive correlation in the concentrations of the high molecular weight PAHs in all smoked fishes from four locations with values between 0.954 and 0.999 for the correlation between any two groups. The polycyclic aromatic hydrocarbon concentration determined in smoked fish samples deceased in terms of location according to the order Winneba > Madina > Chorkor > Ada.

On the deactivation of cobalt-based Fischer-Tropsch synthesis catalysts

NARCIS (Netherlands)

Moodley, D.J.

2008-01-01

The catalytic conversion of synthesis gas, derived from natural gas, into liquid hydrocarbon fuel via the Fischer–Tropsch synthesis (FTS), is currently receiving much attention due to the demand for environmentally friendly liquid fuel and the rising costs of crude oil. From an industrial

Synthesis of hydrocarbons using coal and nuclear process heat

International Nuclear Information System (INIS)

Eickhoff, H.G.; Kugeler, K.

1975-01-01

An analysis of the global petroleum resources and demand shows that the amount of mineral oil products is sufficient to meet the requirements of the next decades. The geographical resources, however, could lead to problems of distribution and foreign exchange. The production of hydrocarbons with coal as basis using high temperature nuclear process heat has advantages compared to the conventional techniques. Next to the conservation of reserve fossil primary energy carriers there are advantages as regards prices, which at high coal costs are especially pronounced. (orig.) [de

New synthesis of carbamate, thiocarbamate and urea type herbicides: preparation of 14C-labelled diuron and EPTC

International Nuclear Information System (INIS)

Volford, J.; Horvath, L.

1981-01-01

N,N-dialkyl-carbamic acid-trimethylsilyl-esters were synthesized starting with 14 CO 2 . The new synthesis route is simple and provides good radiochemical yield. Silyl-carbaminates directly or through carbamoyl-halogenides may be used for preparation of labelled herbicides: carbamates, thiocarbamates and ureas. (author)

Improved ZIF-8 membrane: Effect of activation procedure and determination of diffusivities of light hydrocarbons

KAUST Repository

Pan, Yichang; Liu, Wei; Zhao, Yingjie; Wang, Chongqing; Lai, Zhiping

2015-01-01

Zeolitic imidazolate framework ZIF-8 has shown great potential for effective separation of hydrocarbon mixtures based on its intrinsic ultramicroporous feature. In order to explore the permeation and diffusion properties of hydrocarbons through ZIF-8 membrane, high-quality ZIF-8 membranes with a separation factor of ~90 for propylene/propane are successfully prepared via optimizing the activation processes. Single-component permeation data for hydrocarbons (C1–C4) through the improved ZIF-8 membrane are measured and analyzed by Maxwell-Stefan (MS) model to get the transport diffusivities of these hydrocarbons. The diffusivity values of hydrocarbon compare well with those obtained by other experimental techniques. Binary mixture permeation also can be well predicted through single-component adsorption parameters.

Improved ZIF-8 membrane: Effect of activation procedure and determination of diffusivities of light hydrocarbons

KAUST Repository

Pan, Yichang

2015-06-23

Zeolitic imidazolate framework ZIF-8 has shown great potential for effective separation of hydrocarbon mixtures based on its intrinsic ultramicroporous feature. In order to explore the permeation and diffusion properties of hydrocarbons through ZIF-8 membrane, high-quality ZIF-8 membranes with a separation factor of ~90 for propylene/propane are successfully prepared via optimizing the activation processes. Single-component permeation data for hydrocarbons (C1–C4) through the improved ZIF-8 membrane are measured and analyzed by Maxwell-Stefan (MS) model to get the transport diffusivities of these hydrocarbons. The diffusivity values of hydrocarbon compare well with those obtained by other experimental techniques. Binary mixture permeation also can be well predicted through single-component adsorption parameters.

In vitro toxicity of polycyclic aromatic hydrocarbons and halogenated aromatic hydrocarbons to cetacean cells and tissues

Energy Technology Data Exchange (ETDEWEB)

Carvan, M.J. III.

1993-01-01

Cetaceans bioaccumulate high aromatic hydrocarbon tissue residues, and elevated levels of PCB residues in tissues are proposed to have occurred concurrently with recent epizootic deaths of dolphins. The objectives of this study were: (1) to develop and characterize an epithelial cell line derived from dolphin tissues, (2) to investigate the effects of hydrocarbon pollutants on those cells, and (3) to analyze the toxicity of hydrocarbon pollutants on cetacean tissues in vitro. An epithelial cell line, Carvan dolphin kidney (CDK), isolated from a spontaneously aborted female bottlenose dolphin, Tursiops truncatus, grew rapidly. These cells were neither transformed nor immortal. Velocity sedimentation analysis showed CDK cells contained nuclear aryl hydrocarbon receptor, suggestive of cytochrome P450 inducibility. BaP inhibited mitosis in CDK cells in a dose-dependent manner. Data indicate that CDK cells metabolize BaP, that BaP metabolites bind to cellular DNA initiating unscheduled DNA synthesis, and that the inhibition of cytochrome P450 metabolism decrease the BaP-associated inhibition of mitosis in dolphin cells. The data also suggest that TCDD acts synergistically to increase the levels of DNA damage by the procarcinogen BaP. Cetacean liver microsomes was isolated and evaluated for the presence of cytochrome P450 proteins by SDS-PAGE, apparent minimum molecular weight determination, and immunoblot analysis. P450 activity was induced in cetacean tissue samples and CDK cells by exposure in vitro to one of several cytochrome P450-inducing chemicals. The data suggest that cetacean tissues and cells can be utilized to study the in vitro induction of cytochrome P450, resultant metabolism of xenobiotic contaminants, and the subsequent cellular and molecular responses. However, the identity of specific P450 isozymes involved in this process will remain undetermined until monoclonal antibodies that recognize cetacean P450s can be generated.

Aromatic hydrocarbons

International Nuclear Information System (INIS)

Roder, M.

1985-01-01

Papers dealing with radiolysis of aromatic hydrocarbons of different composition (from benzene to terphenyls and hydrocarbons with condensed rings) as well as their mixtures (with alkanes, alkenes, other aromatic hydrocarbons) are reviewed. High radiation stability of aromatic hydrocarbons in condensed phases associated with peculiarities of molecular structure of compounds is underlined. Mechanisms of radiolytic processes, vaues of product yields are considered

Sulfonated hydrocarbon graft architectures for cation exchange membranes

DEFF Research Database (Denmark)

Nielsen, Mads Møller; Jankova Atanasova, Katja; Hvilsted, Søren

2013-01-01

A synthetic strategy to hydrocarbon graft architectures prepared from a commercial polysulfone and aimed as ion exchange membrane material is proposed. Polystyrene is grafted from a polysulfone macroinitiator by atom transfer radical polymerization, and subsequently sulfonated with acetyl sulfate...... to various degrees. Series of grafting densities and graft lengths are prepared, and membranes are solvent cast from DMSO. The membrane properties in aqueous environments are evaluated from their water swelling behavior, and their thermal properties and stability are investigated by thermogravimetric...

Synthesis of Biokerosene through Electrochemical Hydrogenation of Terpene Hydrocarbons from Turpentine Oil

Directory of Open Access Journals (Sweden)

Tedi Hudaya

2016-12-01

Full Text Available Indonesia possesses great potential for developing renewable resources as alternative fuels. For example, turpentine oil obtained from Pinus merkusii, which contains mostly monoterpene hydrocarbons (C10H16. The oil is highly suitable to be processed for biokerosene or even jet biofuel. It consists of hydrocarbons within the range of C10 to C15. However, it contains insufficient H and thus needs to be upgraded. In the present work, electrochemical hydrogenation was used for upgrading. In the electrochemical cell, stainless steel, silver, and carbon were used alternately for the anode, while copper and silver Raschig rings were used for the cathode. An electrolyte solution of cuprous ammonium formate was utilized not only as a source of H but also to draw the unsaturated hydrocarbons into the aqueous phase. The electrolyte : oil ratio (up to 2:1, electrolyte concentration (between 0.4 and 2 M and reaction time were varied throughout the experiments. The bromine number (unsaturation level of the turpentine oil, which was initially 1,86 (mole Br2/mole, was lowered significantly to 0.69-0.90. Promising increase of smoke point values were observed from 11 mm to 16-24 mm, indicating a higher H content of the processed oil, thus making it suitable as a substitute for petroleum kerosene.

Synthesis of ferrite nanoparticle by milling process for preparation of single domain magnet

International Nuclear Information System (INIS)

Suryadi; Hasbiyallah; Agus S W; Nurul TR; Budhy Kurniawan

2009-01-01

Study of ferrite nanoparticle synthesis for preparation of single domain magnet by milling of scrap magnet material have been done. Sample preparation were done using disk mill continued with high energy milling (HEM). Some powder were taken after 5, 10 dan 20 hours milling using HEM-E3D. The powder were then characterized using X-Ray Fluorescence (XRF), X-Ray Diffractometer (XRD) and Scanning Electron Microscope (SEM). XRF characterization result, confirmed by XRD analysis result, showed that the sample are of Strontium ferrite phase. Microstructure analysis result showed the occurrence of grain refining process of ferrite particle with increasing of milling time. Particle having size of nanometers successfully obtained, although in unhomogeneous distribution. Magnetic properties characterization result showed the increasing of hysteresis curve area of sample for longer milling time and sintering process. (author)

Carbonate loss from two magnesium-substituted carbonated apatites prepared by different synthesis techniques

International Nuclear Information System (INIS)

Barinov, S.M.; Rau, J.V.; Fadeeva, I.V.; Cesaro, S. Nunziante; Ferro, D.; Trionfetti, G.; Komlev, V.S.; Bibikov, V.Yu.

2006-01-01

This study was aimed at the investigation of the thermal stability of Mg-substituted carbonated apatites over the wide temperature range. Two different apatites were studied, which were prepared by either precipitation from aqueous solution or by solid-liquid interaction. The following methods were employed: FTIR spectroscopy of the condensed gas phase to evaluate the CO and CO 2 release with increasing temperature, FTIR of the solid residue after heating, XRD analysis, thermogravimetry and scanning electron microscopy. Decomposition behavior was shown to depend significantly on the synthesis method. Wet-synthesized powders are significantly less thermally stable compared with those prepared by solid-liquid interaction. Intensive release of carbon oxides from the former was observed at 300 deg. C, whereas the latter powder was relatively stable up to temperature about 1000 deg. C

Effect of Ce2O3, La2O3 and ZnO additives on the oxygenates conversion into liquid hydrocarbons

Science.gov (United States)

Kachalov, V. V.; Lavrenov, V. A.; Lishchiner, I. I.; Malova, O. V.; Tarasov, A. L.; Zaichenko, V. M.

2018-01-01

A selective modifying effect of cerium, magnesium and zinc oxide additives on the activity and the selectivity of a pentasil group zeolite catalyst in the reaction of conversion of oxygenates (methanol and dimethyl ether) to liquid hydrocarbons was found. It was found that zinc oxide contributes to the stable operation of the zeolite catalyst in the conversion of oxygenates in the synthesis gas stream and leads to the production of gasolines with low durene content (not more than 6.1 wt%). The obtained results demonstrate the rationale for producing hydrocarbons from synthesis gas without the stage of oxygenate separation with their subsequent conversion to synthetic gasoline.

Flame Synthesis of Single- and Multi-Walled Carbon Nanotubes and Nanofibers

Science.gov (United States)

VanderWal, R. L.; Ticich, Thomas M.

2001-01-01

Metal-catalyzed carbon nanotubes are highly sought for a diverse range of applications that include nanoelectronics, battery electrode material, catalysis, hydrogen storage media and reinforcing agents in polymer composites. These latter applications will require vast quantities of nanotubes at competitive prices to be economically feasible. Moreover, reinforcing applications may not require ultrahigh purity nanotubes. Indeed, functionalization of nanotubes to facilitate interfacial bonding within composites will naturally introduce defects into the tube walls, lessening their tensile strength. Current methods of aerosol synthesis of carbon nanotubes include laser ablation of composite targets of carbon and catalyst metal within high temperature furnaces and decomposition of a organometallics in hydrocarbons mixtures within a tube furnace. Common to each approach is the generation of particles in the presence of the reactive hydrocarbon species at elevated temperatures. In the laser-ablation approach, the situation is even more dynamic in that particles and nanotubes are borne during the transient cooling phase of the laser-induced plasma for which the temperature far exceeds that of the surrounding hot gases within the furnace process tube. A shared limitation is that more efficient methods of nanoparticle synthesis are not readily incorporated into these approaches. In contrast, combustion can quite naturally create nanomaterials such as carbon black. Flame synthesis is well known for its commercial scalability and energy efficiency. However, flames do present a complex chemical environment with steep gradients in temperature and species concentrations. Moreover, reaction times are limited within buoyant driven flows to tens of milliseconds. Therein microgravity can greatly lessen temperature and spatial gradients while allowing independent control of flame residence times. In preparation for defining the microgravity experiments, the work presented here focuses

Flame spray synthesis under a non-oxidizing atmosphere: Preparation of metallic bismuth nanoparticles and nanocrystalline bulk bismuth metal

Energy Technology Data Exchange (ETDEWEB)

Grass, Robert N.; Stark, Wendelin J. [Institute for Chemical and Bioengineering, ETH Zuerich (Switzerland)], E-mail: wendelin.stark@chem.ethz.ch

2006-10-15

Metallic bismuth nanoparticles of over 98% purity were prepared by a modified flame spray synthesis method in an inert atmosphere by oxygen-deficient combustion of a bismuth-carboxylate based precursor. The samples were characterized by X-ray diffraction, thermal analysis and scanning electron microscopy confirming the formation of pure, crystalline metallic bismuth nanoparticles. Compression of the as-prepared powder resulted in highly dense, nanocrystalline pills with strong electrical conductivity and bright metallic gloss.

Use of derivatives to assess preservation of hydrocarbon deposits

Science.gov (United States)

Koshkin, K. A.; Melkishev, O. A.

2018-05-01

The paper considers the calculation of derivatives along the surface of a modern and paleostructure map of a Tl2-b formation top used to forecast the preservation of oil and gas deposits in traps according to 3D seismic survey via statistical methods. It also suggests a method to evaluate morphological changes of the formation top by calculating the difference between derivatives. The proposed method allows analyzing structural changes of the formation top in time towards primary migration of hydrocarbons. The comprehensive use of calculated indicators allowed ranking the prepared structures in terms of preservation of hydrocarbon deposits.

Synthetic crystalline ferroborosilicate compositions, the preparation thereof and their use in the conversion of synthesis gas to low molecular weight hydrocarbons

International Nuclear Information System (INIS)

Hinnenkamp, J.A.; Walatka, V.V.

1987-01-01

A method for the conversion of synthesis gas is described comprising: contacting synthesis gas which comprises hydrogen and carbon monoxide with a catalytically effective amount of a crystalline ferroborosilicate composition, under conversion conditions effective to provide ethane selectivity of at least 40%. The borosilicate composition is represented in terms of mole ratios as follows: (0.2 to 15) M/sub 2/m/O:(0.2 to 10) Z/sub 2/ O /sub 3/: (5 to 1000) SiO/sub 2/: Fe/sub 2/n/O: (0 to 2000) H/sub 2/O wherein M comprises a cation of a quaternary ammonium, metal, ammonium, hydrogen and mixtures thereof, m is the valence of the cation, n is the valence of the iron cation, and Z is boron. The composition contains ion-exchanged palladium or palladium impregnated onto the composition

75 FR 8937 - Development of a Relative Potency Factor (RPF) Approach for Polycyclic Aromatic Hydrocarbon (PAH...

Science.gov (United States)

2010-02-26

... Relative Potency Factor (RPF) Approach for Polycyclic Aromatic Hydrocarbon (PAH) Mixtures AGENCY... Aromatic Hydrocarbon (PAH) Mixtures'' (EPA/635/R-08/012A). The draft document was prepared by the National... 27, 2010. The listening session on the draft document for PAH mixtures will be held on April 7, 2010...

La{sub 2-x}Sr{sub x}NiO{sub 4+{delta}} ceramic powders prepared by combustion synthesis

Energy Technology Data Exchange (ETDEWEB)

Colomer, M.T.; Chinarro, E.; Jurado, J.R. [Consejo Nacional de Investigaciones Cientificas, Madrid (Spain). Ist. de Ceramica y Vidrio

2002-07-01

Combustion synthesis provides an attractive method of producing ceramic powders because of its low cost, process simplicity and fastness. Materials based on La{sub 2}NiO{sub 4+{delta}} can be successfully prepared by combustion synthesis. La{sub 2-x}Sr{sub x}NiO{sub 4+{delta}} (x = 0, 0.1) accommodates oxygen excess by oxygen interstitials rather than by the more usual cation vacancies. A high concentration of oxygen interstitials offers the possibility of rapid oxygen transport through the ceramic material and thus provide a new type of mixed ionic-electronic conductor. The fast oxide ion diffusion combined with its thermal stability indicate that these materials would be good candidates for use in ceramic oxygen generators (COGs) and intermediate temperature solid oxide fuel cells (IT-SOFCs). The present work discusses a combustion synthesis technique to prepare La{sub 2-x}Sr{sub x}NiO{sub 4+{delta}} (x = 0, 0.1) powders using the corresponding metal nitrates-urea mixtures, at low temperature and short reaction times. The as-prepared combustion powders were characterized by XRD, DTA-TG, SEM/TEM-EDX and BET. La{sub 2-x}Sr{sub x}NiO{sub 4} (x = 0, 0.1) powders with a good compositional control and homogeneity are attained. The as-prepared powders obtained at 300 C (ignition temperature) showed much higher specific surface area than powders obtained via alternative routes and contained La{sub 2-x}Sr{sub x}NiO{sub 4+{delta}}, as the major phase present, together with La{sub 2}O{sub 3} and a small amount of NiO. La{sub 2-x}Sr{sub x}NiO{sub 4+{delta}} single phase is achieved, respectively at 950 C for x =0.1 and at 975 C for x = 0. (orig.)

Preparation and characterization of new zeolite membranes. Application to gaseous separation; Preparation et caracterisation de nouvelles membranes de zeolithe application a la separation gazeuse

Energy Technology Data Exchange (ETDEWEB)

Anstett, M.

1996-11-25

Zeolites are interesting for the preparation of inorganic membranes which could be used for the continuous separation of gas and liquids by gas permeation and pervaporation. Zeolites membranes are obtained by hydrothermal synthesis and are characterized by XRD, SEM, TDA, IR, chemical analysis, EPMA, NMR, MAS NMR and gas permeation. After some tests of preparation of zeolite CHA and MFI self supporting membranes, the work is turned towards the preparation of zeolite MFI membranes supported by porous disks or {alpha} alumina, glass and tubes of carbon covered with a thin layer or zirconium dioxide. It is shown that the characteristics of the support (reactivity, pores dimensions, ...) strongly influence the quality of the prepared membrane. Two originals preparation processes are finalized. For the alumina disks, a gel precursor of zeolite is firs formed at the surface of the support by immersing successively that support in two non miscible liquids before the crystallisation. The gel is then converted into the zeolite by contact with water vapor. The zeolite layer obtained is localized at the surface of the support and present not only at the outside but also at the inside of the support. The characteristics of the zeolite layer can be controlled and the method can be adapted to various porous supports. The membrane obtained is interesting for hydrocarbons separations, for example the separation of methane and isobutane. In the case of Vycor glass disks, the reactivity of the support is first enhanced by contact with saturated water vapour. The temperature of the synthesis is then chosen relatively low in order to limit the attack of the support. With that method, a basic solution can be used without degradation of the support.The basicity leads to the formation of little crystals whose assembling is compact and homogeneous. The membrane obtained is interesting for example for the separation of normal butane and isobutane. (author) 71 refs.

Synthesis of Cu[MIBI]4Cl to prepare 99m Tc [MIBI]6+ as a myocardial perfusion agent

International Nuclear Information System (INIS)

Ramirez G, L.

1994-01-01

2-Methoxyisobutylisonitrile (MIBI) is a key starting material in the preparation of technetium-99m hexakis (2-methoxyisobutylisonitrile). This cationic complex has been reported to be clinically useful as myocardial perfusion agent. In this work, we designed an improved synthetic method to prepare 2-methoxyisobutylisonitrile in a two step synthesis with an overall yield of 52.9 % , on the basis of 2-methoxyisobutylamine is a primary amine which, when is heated with a mixture of chloroform and alcoholic potash, produces an isonitrile. Its spectroscopic properties as well as the preparation of its copper and technetium-99m complexes are also presented. (Author)

Evaluation of mineral oil saturated hydrocarbons (MOSH and mineral oil aromatic hydrocarbons (MOAH in pure mineral hydrocarbon-based cosmetics and cosmetic raw materials using 1H NMR spectroscopy [version 2; referees: 3 approved

Directory of Open Access Journals (Sweden)

Dirk W. Lachenmeier

2017-08-01

Full Text Available Mineral hydrocarbons consist of two fractions, mineral oil saturated hydrocarbons (MOSH and mineral oil aromatic hydrocarbons (MOAH. MOAH is a potential public health hazard because it may include carcinogenic polycyclic compounds. In the present study, 400 MHz nuclear magnetic resonance (NMR spectroscopy was introduced, in the context of official controls, to measure MOSH and MOAH in raw materials or pure mineral hydrocarbon final products (cosmetics and medicinal products. Quantitative determination (qNMR has been established using the ERETIC methodology (electronic reference to access in vivo concentrations based on the PULCON principle (pulse length based concentration determination. Various mineral hydrocarbons (e.g., white oils, paraffins or petroleum jelly were dissolved in deuterated chloroform. The ERETIC factor was established using a quantification reference sample containing ethylbenzene and tetrachloronitrobenzene. The following spectral regions were integrated: MOSH δ 3.0 – 0.2 ppm and MOAH δ 9.2 - 6.5, excluding solvent signals. Validation showed a sufficient precision of the method with a coefficient of variation <6% and a limit of detection <0.1 g/100 g. The applicability of the method was proven by analysing 27 authentic samples with MOSH and MOAH contents in the range of 90-109 g/100 g and 0.02-1.10 g/100 g, respectively. It is important to distinguish this new NMR-approach from the hyphenated liquid chromatography-gas chromatography methodology previously used to characterize MOSH/MOAH amounts in cosmetic products. For mineral hydrocarbon raw materials or pure mineral hydrocarbon-based cosmetic products, NMR delivers higher specificity without any sample preparation besides dilution. Our sample survey shows that previous methods may have overestimated the MOAH amount in mineral oil products and opens new paths to characterize this fraction. Therefore, the developed method can be applied for routine monitoring of consumer

Biodegradation testing of hydrophobic chemicals in mixtures at low concentrations – covering the chemical space of petroleum hydrocarbons

DEFF Research Database (Denmark)

Birch, Heidi; Hammershøj, Rikke Høst; Mayer, Philipp

Petroleum products are complex mixtures of varying composition containing thousands of hydrocarbons each with their own physicochemical properties and degradation kinetics. One approach for risk assessment of these products is therefore to group the hydrocarbons by carbon number and chemical class...... i.e. hydrocarbon blocks. However, the biodegradation kinetic data varies in quantity and quality for the different hydrocarbon blocks, hampering the characterization of their fate properties. In this study, biodegradation kinetics of a large number of hydrocarbons aiming to cover the chemical space...... of petroleum hydrocarbons, were therefore determined at ng/L to µg/L concentrations in surface water, seawater and activated sludge filtrate. Two hydrocarbon mixtures were prepared, comprising a total of 53 chemicals including paraffins, naphthenics and aromatic hydrocarbons from C8 to C20. Passive dosing from...

Thermoluminescence study of aluminium oxide doped germanium prepared by combustion synthesis method

Directory of Open Access Journals (Sweden)

Saharin Nurul Syazlin Binti

2017-01-01

Full Text Available The present paper reports the optimum concentration of germanium (Ge dopant in aluminium oxide (AhO3 samples prepared by combustion synthesis (CS method for thermoluminescence (TL studies. The samples were prepared at various Ge concentration i.e. 1 to 5% mol. The phase formation of un-doped and Ge-doped Al2O3 samples was determined using X-ray Diffraction (XRD. The sharp peaks present in the XRD pattern confirms the crystallinity of the samples. The samples were then exposed to 50 Gy Cobalt-60 sources (Gamma cell 220. TL glow curves were measured and recorded using a Harshaw Model 3500 TLD reader. Comparison of TL peaks were observed to obtain the best composition of Ge dopants. A simple glow curves TL peak at around 175̊C for all composition samples was observed. It was also found that the composition of aluminium oxide doped with 3.0% of germanium exhibits the highest thermoluminescence (TL intensity which is 349747.04 (a.u.

The effect of Centella asiatica, vitamins, glycolic acid and their mixtures preparations in stimulating collagen and fibronectin synthesis in cultured human skin fibroblast.

Science.gov (United States)

Hashim, Puziah

2014-03-01

Centella asiatica (Linn.) Urban is well known in promoting wound healing and provides significant benefits in skin care and therapeutic products formulation. Glycolic acid and vitamins also play a role in the enhancement of collagen and fibronectin synthesis. Here, we evaluate the specific effect of Centella asiatica (CA), vitamins, glycolic acid and their mixture preparations to stimulate collagen and fibronectin synthesis in cultured human fibroblast cells. The fibroblast cells are incubated with CA, glycolic acid, vitamins and their mixture preparations for 48 h. The cell lysates were analyzed for protein content and collagen synthesis by direct binding enzyme immunoassay. The fibronectin of the cultured supernatant was measured by sandwich enzyme immunoassay. The results showed that CA, glycolic acid, vitamins A, E and C significantly stimulate collagen and fibronectin synthesis in the fibroblast. Addition of glycolic acid and vitamins to CA further increased the levels of collagen and fibronectin synthesis to 8.55 and 23.75 μg/100 μg, respectively. CA, glycolic acid, vitamins A, E, and C, and their mixtures demonstrated stimulatory effect on both extra-cellular matrix synthesis of collagen and fibronectin in in vitro studies on human foreskin fibroblasts, which is beneficial to skin care and therapeutic products formulation.

Origin and mobility of hydrocarbon gases in alkaline plutons : the example of the Khibina complex, NW Russia

Energy Technology Data Exchange (ETDEWEB)

Treloar, P.J.; Beeskow, B.; Rankin, A.H. [Kingston Univ., Kingston upon Thames (United Kingdom). School of Earth Sciences; Potter, J. [Western Ontario Univ., London, ON (Canada). Dept. of Earth Science; Nivin, V. [Geological Inst., Apatity (Russian Federation). Kola Science Centre

2006-07-01

The origin and distribution of abiogenic hydrocarbon gases (HCGs) was discussed with particular reference to HCGs in the Khibina pluton which are dominated by methane (CH{sub 4}) with minor amounts of higher hydrocarbons and hydrogen (H{sub 2}). Although isotopic data and hydrocarbon species ratios point to an abiogenic source, they do not distinguish between primary magmatic hydrocarbons and those generated by late magmatic re-speciation or post-magmatic Fischer-Tropsch (FT) synthesis. Some rock textures suggest limited CH{sub 4} production by FT synthesis, but the presence of primary, syn-magmatic CH{sub 4}-rich fluid inclusions, and the absence of primary and secondary carbon dioxide (CO{sub 2}) rich inclusions, suggest a dominantly early magmatic origin for the HCGs. The permeability and porosity in the Khibina pluton can be constrained by the distribution and geometry of fluid inclusion planes (FIPs) and open cracks (OCs), as well as by the magnitude and pathways of fluid flow. Orientation data for FIPs and OCs, obtained from oriented thin sections, revealed a range of orientations in sub-parallel arrays, suggesting continual re-activation of old fracture systems. The extensive occurrence of OCs and sealed FIPs points to long lived porosities and permeabilities with large fluid fluxes integrated over time. FIP and OC density values were found to be consistent with gas release patterns characterized by spontaneous release during mining of large volumes of HCG stored in a network of interconnected, sealed microfractures and fluid inclusion planes that unzip during stress. It was determined that the HCGs have a primary magmatic origin although there is local evidence for limited post-magmatic FT synthesis. Long term continuous gas migration has occurred within the complex through an interconnected set of fractures. FIPs represent aliquots of gas sealed during open system migration. It was concluded that the complex contains a potentially economically viable

Composite catalyst for carbon monoxide and hydrocarbon oxidation

Science.gov (United States)

Liu, Wei; Flytzani-Stephanopoulos, Maria

1996-01-01

A method and composition for the complete oxidation of carbon monoxide and/or hydrocarbon compounds. The method involves reacting the carbon monoxide and/or hydrocarbons with an oxidizing agent in the presence of a metal oxide composite catalyst. The catalyst is prepared by combining fluorite-type oxygen ion conductors with active transition metals. The fluorite oxide, selected from the group consisting of cerium oxide, zirconium oxide, thorium oxide, hafnium oxide, and uranium oxide, and may be doped by alkaline earth and rare earth oxides. The transition metals, selected from the group consisting of molybdnum, copper, cobalt, maganese, nickel, and silver, are used as additives. The atomic ratio of transition metal to fluorite oxide is less than one.

Modeling the Thermal Rocket Fuel Preparation Processes in the Launch Complex Fueling System

Directory of Open Access Journals (Sweden)

A. V. Zolin

2015-01-01

Full Text Available It is necessary to carry out fuel temperature preparation for space launch vehicles using hydrocarbon propellant components. A required temperature is reached with cooling or heating hydrocarbon fuel in ground facilities fuel storages. Fuel temperature preparing processes are among the most energy-intensive and lengthy processes that require the optimal technologies and regimes of cooling (heating fuel, which can be defined using the simulation of heat exchange processes for preparing the rocket fuel.The issues of research of different technologies and simulation of cooling processes of rocket fuel with liquid nitrogen are given in [1-10]. Diagrams of temperature preparation of hydrocarbon fuel, mathematical models and characteristics of cooling fuel with its direct contact with liquid nitrogen dispersed are considered, using the numerical solution of a system of heat transfer equations, in publications [3,9].Analytical models, allowing to determine the necessary flow rate and the mass of liquid nitrogen and the cooling (heating time fuel in specific conditions and requirements, are preferred for determining design and operational characteristics of the hydrocarbon fuel cooling system.A mathematical model of the temperature preparation processes is developed. Considered characteristics of these processes are based on the analytical solutions of the equations of heat transfer and allow to define operating parameters of temperature preparation of hydrocarbon fuel in the design and operation of the filling system of launch vehicles.The paper considers a technological system to fill the launch vehicles providing the temperature preparation of hydrocarbon gases at the launch site. In this system cooling the fuel in the storage tank before filling the launch vehicle is provided by hydrocarbon fuel bubbling with liquid nitrogen. Hydrocarbon fuel is heated with a pumping station, which provides fuel circulation through the heat exchanger-heater, with

Magnetic graphene oxide as adsorbent for the determination of polycyclic aromatic hydrocarbon metabolites in human urine.

Science.gov (United States)

Zhu, Linli; Xu, Hui

2014-09-01

Detection of monohydroxy polycyclic aromatic hydrocarbons metabolites in urine is an advisable and valid method to assess human environmental exposure to polycyclic aromatic hydrocarbons. In this work, novel Fe3O4/graphene oxide composites were prepared and their application in the magnetic solid-phase extraction of monohydroxy polycyclic aromatic hydrocarbons in urine was investigated by coupling with liquid chromatography and mass spectrometry. In the hybrid material, superparamagnetic Fe3O4 nanoparticles provide fast separation to simplify the analytical process and graphene oxide provides a large functional surface for the adsorption. The prepared magnetic nanocomposites were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and vibrating sample magnetometry. The experimental conditions were optimized systematically. Under the optimal conditions, the recoveries of these compounds were in the range of 98.3-125.2%, the relative standard deviations ranged between 6.8 and 15.5%, and the limits of detection were in the range of 0.01-0.15 ng/mL. The simple, quick, and affordable method was successfully used in the analysis of human urinary monohydroxy polycyclic aromatic hydrocarbons in two different cities. The results indicated that the monohydroxy polycyclic aromatic hydrocarbons level in human urine can provide useful information for environmental exposure to polycyclic aromatic hydrocarbons. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Two-step processing of oil shale to linear hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Eliseev, O.L.; Ryzhov, A.N.; Latypova, D.Zh.; Lapidus, A.L. [Russian Academy of Sciences, Moscow (Russian Federation). N.D. Zelinsky Institute of Organic Chemistry; Avakyan, T.A. [Gubkin Russian State University of Oil and Gas, Moscow (Russian Federation)

2013-11-01

Thermal and catalytic steam reforming of oil shale mined from Leningrad and Kashpir deposits was studied. Experiments were performed in fixed bed reactor by varying temperature and steam flow rate. Data obtained were approximated by empirical formulas containing some parameters calculated by least-squares method. Thus predicting amount of hydrogen, carbon monoxide and methane in producer gas is possible for given particular kind of oil shale, temperature and steam flow rate. Adding Ni catalyst enriches hydrogen and depletes CO content in effluent gas at low gasification temperatures. Modeling gas simulating steam reforming gases (H{sub 2}, CO, CO{sub 2}, and N{sub 2} mixture) was tested in hydrocarbon synthesis over Co-containing supported catalyst. Selectivity of CO conversion into C{sub 5+} hydrocarbons reaches 84% while selectivity to methane is 7%. Molecular weight distribution of synthesized alkanes obeys Anderson-Schulz-Flory equation and chain growth probability 0.84. (orig.)

Laboratory analytical methods for the determination of the hydrocarbon status of soils (a review)

Science.gov (United States)

Pikovskii, Yu. I.; Korotkov, L. A.; Smirnova, M. A.; Kovach, R. G.

2017-10-01

Laboratory analytical methods suitable for the determination of the hydrocarbon status of soils (a specific soil characteristic involving information on the total content and qualitative features of soluble (bitumoid) carbonaceous substances and individual hydrocarbons (polycyclic aromatic hydrocarbons, alkanes, etc.) in bitumoid, as well as the composition and content of hydrocarbon gases) have been considered. Among different physicochemical methods of study, attention is focused on the methods suitable for the wide use. Luminescence-bituminological analysis, low-temperature spectrofluorimetry (Shpolskii spectroscopy), infrared (IR) spectroscopy, gas chromatography, chromatography-mass spectrometry, and some other methods have been characterized, as well as sample preparation features. Advantages and limitations of each of these methods are described; their efficiency, instrumental complexity, analysis duration, and accuracy are assessed.

Efficient Synthesis of β-Aryl-γ-lactams and Their Resolution with (S-Naproxen: Preparation of (R- and (S-Baclofen

Directory of Open Access Journals (Sweden)

Iris J. Montoya-Balbás

2015-12-01

Full Text Available An efficient synthesis of enantiomerically-pure β-aryl-γ-lactams is described. The principal feature of this synthesis is the practical resolution of β-aryl-γ-lactams with (S-Naproxen. The procedure is based on the Michael addition of nitromethane to benzylidenemalonates, which was easily obtained, followed by the reduction of the γ-nitroester in the presence of Raney nickel and the subsequent saponification/decarboxylation reaction. The utility of this methodology was highlighted by the preparation of enantiomerically-pure (R- and (S-Baclofen hydrochloride.

Preparation of carbon-11 labelled phenylalanine and phenylglycine by a new amino acid synthesis

International Nuclear Information System (INIS)

Vaalburg, W.; Beerling-van der Molen, H.D.; Reiffers, S; Rijskamp, A.; Woldring, M.G.; Wynberg, H.

1976-01-01

Of the cyclotron-produced short-lived isotopes carbon-11 (tsub(1/2) = 20.4 min;β + ) is one of the most promising as label for radiopharmaceuticals. To prepare 11 C-labelled amino acids for evaluation as pancreas scanning agents a new rapid amino acid synthesis was developed. The method is based on the carboxylation of α-lithioisocyanides with 11 CO 2 , followed by hydrolysis of the intermediate reaction product to the desired amino acid. By this method DL-α-phenylalanine-1- 11 C and DL-α-phenylglycine-1- 11 C were prepared. The precursor 11 CO 2 was produced via the 14 N(p,α) 11 C reaction by bombardment of a flow of nitrogen gas mixed with 0.1% 0 2 with 20 MeV protons. The target system is described. (author)

Selective transformation of syngas into gasoline-range hydrocarbons over mesoporous H-ZSM-5-supported cobalt nanoparticles.

Science.gov (United States)

Cheng, Kang; Zhang, Lei; Kang, Jincan; Peng, Xiaobo; Zhang, Qinghong; Wang, Ye

2015-01-26

Bifunctional Fischer-Tropsch (FT) catalysts that couple uniform-sized Co nanoparticles for CO hydrogenation and mesoporous zeolites for hydrocracking/isomerization reactions were found to be promising for the direct production of gasoline-range (C5-11 ) hydrocarbons from syngas. The Brønsted acidity results in hydrocracking/isomerization of the heavier hydrocarbons formed on Co nanoparticles, while the mesoporosity contributes to suppressing the formation of lighter (C1-4 ) hydrocarbons. The selectivity for C5-11 hydrocarbons could reach about 70 % with a ratio of isoparaffins to n-paraffins of approximately 2.3 over this catalyst, and the former is markedly higher than the maximum value (ca. 45 %) expected from the Anderson-Schulz-Flory distribution. By using n-hexadecane as a model compound, it was clarified that both the acidity and mesoporosity play key roles in controlling the hydrocracking reactions and thus contribute to the improved product selectivity in FT synthesis. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The role of graphene-based sorbents in modern sample preparation techniques.

Science.gov (United States)

de Toffoli, Ana Lúcia; Maciel, Edvaldo Vasconcelos Soares; Fumes, Bruno Henrique; Lanças, Fernando Mauro

2018-01-01

The application of graphene-based sorbents in sample preparation techniques has increased significantly since 2011. These materials have good physicochemical properties to be used as sorbent and have shown excellent results in different sample preparation techniques. Graphene and its precursor graphene oxide have been considered to be good candidates to improve the extraction and concentration of different classes of target compounds (e.g., parabens, polycyclic aromatic hydrocarbon, pyrethroids, triazines, and so on) present in complex matrices. Its applications have been employed during the analysis of different matrices (e.g., environmental, biological and food). In this review, we highlight the most important characteristics of graphene-based material, their properties, synthesis routes, and the most important applications in both off-line and on-line sample preparation techniques. The discussion of the off-line approaches includes methods derived from conventional solid-phase extraction focusing on the miniaturized magnetic and dispersive modes. The modes of microextraction techniques called stir bar sorptive extraction, solid phase microextraction, and microextraction by packed sorbent are discussed. The on-line approaches focus on the use of graphene-based material mainly in on-line solid phase extraction, its variation called in-tube solid-phase microextraction, and on-line microdialysis systems. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Hydrocarbon-degrading sulfate-reducing bacteria in marine hydrocarbon seep sediments

OpenAIRE

Kleindienst, Sara

2012-01-01

Microorganisms are key players in our biosphere because of their ability to degrade various organic compounds including a wide range of hydrocarbons. At marine hydrocarbon seeps, more than 90% of sulfate reduction (SR) is potentially coupled to non-methane hydrocarbon oxidation. Several hydrocarbon-degrading sulfate-reducing bacteria (SRB) were enriched or isolated from marine sediments. However, in situ active SRB remained largely unknown. In the present thesis, the global distribution and a...

Zinc oxide/polypyrrole nanocomposite as a novel solid phase microextraction coating for extraction of aliphatic hydrocarbons from water and soil samples

International Nuclear Information System (INIS)

Amanzadeh, Hatam; Yamini, Yadollah; Moradi, Morteza

2015-01-01

Highlights: • ZnO/polypyrrole (ZNO/PPY) nanocomposite coating was fabricated on stainless steel. • Nanocomposite coating morphology was evaluated using scanning electron microscopy. • It was applied for HS-SPME of aliphatic hydrocarbons in water and soil samples. • Separation and determination of the hydrocarbons were performed by GC-FID. • The method is suitable for routine analysis of n-alkanes in various environmental samples. - Abstract: In this work, ZnO/PPy nanocomposite coating was fabricated on stainless steel and evaluated as a novel headspace solid phase microextraction (HS-SPME) fiber coating for extraction of ultra-trace amounts of environmental pollutants; namely, aliphatic hydrocarbons in water and soil samples. The ZnO/PPy nanocomposite were prepared by a two-step process including the electrochemical deposition of PPy on the surface of stainless steel in the first step, and the synthesis of ZnO nanorods by hydrothermal process in the pores of PPy matrix in the second step. Porous structure together with ZnO nanorods with the average diameter of 70 nm were observed on the surface by using scanning electron microscopy (SEM). The effective parameters on HS-SPME of hydrocarbons (i.e., extraction temperature, extraction time, desorption temperature, desorption time, salt concentration, and stirring rate) were investigated and optimized by one-variable-at-a-time method. Under optimized conditions (extraction temperature, 65 ± 1 °C; extraction time, 15 min; desorption temperature, 250 °C; desorption time, 3 min; salt concentration, 10% w/v; and stirring rate, 1200 rpm), the limits of detection (LODs) were found in the range of 0.08–0.5 μg L −1 , whereas the repeatability and fiber-to-fiber reproducibility were in the range 5.4–7.6% and 8.6–10.4%, respectively. Also, the accuracies obtained for the spiked n-alkanes were in the range of 85–108%; indicating the absence of matrix effects in the proposed HS-SPME method. The results

Zinc oxide/polypyrrole nanocomposite as a novel solid phase microextraction coating for extraction of aliphatic hydrocarbons from water and soil samples

Energy Technology Data Exchange (ETDEWEB)

Amanzadeh, Hatam; Yamini, Yadollah [Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175 Tehran (Iran, Islamic Republic of); Moradi, Morteza [Department of Semiconductors, Materials and Energy Research Center, Karaj (Iran, Islamic Republic of)

2015-07-16

Highlights: • ZnO/polypyrrole (ZNO/PPY) nanocomposite coating was fabricated on stainless steel. • Nanocomposite coating morphology was evaluated using scanning electron microscopy. • It was applied for HS-SPME of aliphatic hydrocarbons in water and soil samples. • Separation and determination of the hydrocarbons were performed by GC-FID. • The method is suitable for routine analysis of n-alkanes in various environmental samples. - Abstract: In this work, ZnO/PPy nanocomposite coating was fabricated on stainless steel and evaluated as a novel headspace solid phase microextraction (HS-SPME) fiber coating for extraction of ultra-trace amounts of environmental pollutants; namely, aliphatic hydrocarbons in water and soil samples. The ZnO/PPy nanocomposite were prepared by a two-step process including the electrochemical deposition of PPy on the surface of stainless steel in the first step, and the synthesis of ZnO nanorods by hydrothermal process in the pores of PPy matrix in the second step. Porous structure together with ZnO nanorods with the average diameter of 70 nm were observed on the surface by using scanning electron microscopy (SEM). The effective parameters on HS-SPME of hydrocarbons (i.e., extraction temperature, extraction time, desorption temperature, desorption time, salt concentration, and stirring rate) were investigated and optimized by one-variable-at-a-time method. Under optimized conditions (extraction temperature, 65 ± 1 °C; extraction time, 15 min; desorption temperature, 250 °C; desorption time, 3 min; salt concentration, 10% w/v; and stirring rate, 1200 rpm), the limits of detection (LODs) were found in the range of 0.08–0.5 μg L{sup −1}, whereas the repeatability and fiber-to-fiber reproducibility were in the range 5.4–7.6% and 8.6–10.4%, respectively. Also, the accuracies obtained for the spiked n-alkanes were in the range of 85–108%; indicating the absence of matrix effects in the proposed HS-SPME method. The results

Alternative Fuels and Chemicals from Synthesis Gas

Energy Technology Data Exchange (ETDEWEB)

None, None

1998-12-02

The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.

Alternative fuels and chemicals from synthesis gas

Energy Technology Data Exchange (ETDEWEB)

Unknown

1998-08-01

The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.

ALTERNATIVE FUELS AND CHEMICALS FROM SYNTHESIS GAS

Energy Technology Data Exchange (ETDEWEB)

Unknown

1999-01-01

The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.

Alternative Fuels and Chemicals From Synthesis Gas

Energy Technology Data Exchange (ETDEWEB)

none

1998-07-01

The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.

Tuning functionality of photocatalytic materials: an infrared study on hydrocarbon oxidation

NARCIS (Netherlands)

Amrollahi Buky, Rezvaneh

2016-01-01

The focus of the research described in this thesis was on the engineering and design of effective photocatalysts able to catalyze the oxidative conversion of hydrocarbons. The prepared catalysts were synthesized by using different procedures involving sol gel precursors, and impregnation or

Certain aspects of the formation and identification of nanosized oxide components in heterogeneous catalysts prepared by different methods

International Nuclear Information System (INIS)

Ellert, Ol'ga G; Novotortsev, Vladimir M; Tsodikov, Mark V

2010-01-01

The results of studies into the relationship 'methods and synthesis conditions of a catalyst→catalyst structure→catalytic properties' in highly efficient crystallo-graphically amorphous copper- and iron-containing heterogeneous systems obtained by different chemical methods are generalized. Polymorphism of active phases and catalytic properties of nanostructured copper-containing zinc, zirconium, manganese and cerium oxides are discussed. Unusual transformations of nanosized Pt- and Pd-containing components on the γ-Al 2 O 3 surface in nanostructured catalysts of ethanol steam reforming into synthesis gas and reductive dehydration of ethanol to alkanes are considered. The results of comparative studies on the crystallographically amorphous mixed iron oxide catalysts synthesized by either the alkoxy method or the deposition on various supports obtained by the Moessbauer and XAFS spectroscopy and magnetic susceptibility measurements are presented. These materials are shown to be efficient catalysts of important processes such as liquid-phase oxidation of hydrocarbons, synthesis of alkenes and alkylaromatic hydrocarbons from CO and H 2 , hydrogenative transformation of brown coal organic mass to hydrocarbons.

Fiscal 1997 report on the results of the international research cooperation project for a feasibility survey for finding out seeds of the international joint research. Effective use technology of saturated hydrocarbon (technology against the surplus aromatic hydrocarbon/technology of high grade treatment of petroleum coke); 1997 nendo kokusai kenkyu kyoryoku jigyo (kokusai kyodo kenkyu seeds hakkutsu no tame no FS chosa). Howa tanka suiso no yuko riyo gijutsu / hokozoku tanka suiso no yojo taisaku gijutsu / sekiyu cokes no kodo shori gijutsu seika hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-03-01

For the purpose of the effective international research cooperation, the paper surveyed in fiscal 1997 the effective use technology of saturated hydrocarbon, technology against the surplus aromatic hydrocarbon and technology of high grade treatment of petroleum coke. In the survey of the effective use technology of saturated hydrocarbon, trends of FT synthesis technology and DME synthesis technology were studied as trends of technology to produce synthetic gas, and a project was proposed for technical development of using natural gas as liquid fuel in Japan. In the survey of technology against the surplus aromatic hydrocarbon, studied were the benzene law regulation and the supply/demand trend of aromatic hydrocarbon, process to reduce production of aromatic hydrocarbon as much as possible, process to reduce aromatics of the produced petroleum products, and process to effectively use aromatic hydrocarbon as chemical raw material. In the survey of high grade treatment of petroleum coke, studied were a possibility of using HS petroleum coke in the DIOS method, iron bath gasification, and copper bath gasification technology. 108 refs., 146 figs., 103 tabs.

Petroleum formation by Fischer-Tropsch synthesis in plate tectonics

Energy Technology Data Exchange (ETDEWEB)

Szatmari, P. (Petrobras Research Center, Rio de Janeiro (Brazil))

1989-08-01

A somewhat speculative hypothesis of petroleum genesis in the upper lithosphere is proposed, based on Fischer-Tropsch synthesis. This hypothesis is distinct from both the organic (biogenic) model and the inorganic model of hydrocarbon degassing from the Earth's interior. The hypothesis presented in this paper proposes that petroleum liquids form by Fischer-Tropsch synthesis on magnetite and hematite catalysts when carbon dioxide (derived by massive metamorphic or igneous decarbonation of subducted sedimentary carbonates) reacts with hydrogen generated by the serpentinization (in the absence of air) of shallow-mantle lithosphere and ophiolite thrust sheets. Oblique plate movements may favor hydrocarbon formation by creating deep faults that aid fluid flow and serpentinization. The world's richest oil provinces, including those of the Middle East, may be tentatively interpreted to have formed by this mechanism. 8 figs., 1 tab.

[Efficiency of the preparation "Ekolan-M" for purification of oil polluted soil].

Science.gov (United States)

Nogina, T M; Dumanskaia, T U; Khomenko, L A; Podgorskiĭ, V S

2012-01-01

The efficiency of purification of oil contaminated loamy chernozem by the preparation "Ekolan-M" was investigated. During 12 months a complex soil bioremediation using the preparation and alfalfa, as the land-improving plant, at the final stage of purification resulted in the reduction of hydrocarbon content by 97.0%, and without the preparation - by 65.5 %. In the version of experiment with the preparation a 100% decrease of soil phytotoxicity was achieved and a significant stimulation of plant growth and development was observed. The process of soil purification was accompanied by intensive development of hydrocarbon-oxidizing microorganisms, the amount of which during the process of oil concentration gradually decreased, approaching the level in the control uncontaminated soil.

Synthesis and preparation of biocompatible and pH-responsive cyclodextrin-based nanoparticle

International Nuclear Information System (INIS)

Hu, Xiaohong; Chen, Shangneng; Gong, Xiao; Gao, Ziyu; Wang, Xin; Chen, Pin

2017-01-01

As a temporarily protective reaction for active hydrogen group, acetylation is reversible and responsive to low pH value. According to the reaction, pH-sensitive β-cyclodextrin (β-CD) was synthesized in the first step of our research. During the synthesis, the acetal groups including linear acetal (LA) groups and cyclic acetal (CA) groups were successfully modified onto β-CD. Particularly, the structural details of acetalated β-CD (Ac-β-CD) were greatly influenced by reaction time. Furthermore, in respect to water solubility, Ac-β-CDs exhibited different pH response properties due to their different structure. In the second step, Ac-β-CD1 nanoparticles were prepared by a single oil-in-water (O/W) emulsion technique using a biocompatible emulsifier, gelatin. Meanwhile, gelatin was absorbed onto the surface of nanoparticle, which was confirmed by FTIR spectra. The formed nanoparticles showed monodispersion and nearly spherical morphology. In order to obtain optimal preparing conditions, the effects of preparative parameters such as gelatin concentration, Ac-β-CD concentration, and water/oil ratio on properties including diameters and zeta potential as well as gelatin content were investigated. Moreover, the pH response properties of nanoparticle were characterized by transparency of nanoparticle solution. Finally, in vitro cell culture confirmed that Ac-β-CD nanoparticle could support cell survival and enhance cell viability.

Synthesis and preparation of biocompatible and pH-responsive cyclodextrin-based nanoparticle

Energy Technology Data Exchange (ETDEWEB)

Hu, Xiaohong, E-mail: huxiaohong07@163.com; Chen, Shangneng [Jinling Institute of Technology, School of Material Engineering (China); Gong, Xiao [Wuhan University of Technology, State Key Laboratory of Silicate Materials for Architectures (China); Gao, Ziyu; Wang, Xin; Chen, Pin [Jinling Institute of Technology, School of Material Engineering (China)

2017-03-15

As a temporarily protective reaction for active hydrogen group, acetylation is reversible and responsive to low pH value. According to the reaction, pH-sensitive β-cyclodextrin (β-CD) was synthesized in the first step of our research. During the synthesis, the acetal groups including linear acetal (LA) groups and cyclic acetal (CA) groups were successfully modified onto β-CD. Particularly, the structural details of acetalated β-CD (Ac-β-CD) were greatly influenced by reaction time. Furthermore, in respect to water solubility, Ac-β-CDs exhibited different pH response properties due to their different structure. In the second step, Ac-β-CD1 nanoparticles were prepared by a single oil-in-water (O/W) emulsion technique using a biocompatible emulsifier, gelatin. Meanwhile, gelatin was absorbed onto the surface of nanoparticle, which was confirmed by FTIR spectra. The formed nanoparticles showed monodispersion and nearly spherical morphology. In order to obtain optimal preparing conditions, the effects of preparative parameters such as gelatin concentration, Ac-β-CD concentration, and water/oil ratio on properties including diameters and zeta potential as well as gelatin content were investigated. Moreover, the pH response properties of nanoparticle were characterized by transparency of nanoparticle solution. Finally, in vitro cell culture confirmed that Ac-β-CD nanoparticle could support cell survival and enhance cell viability.

Bio-remediation of a sludge containing hydrocarbons

International Nuclear Information System (INIS)

Ayotamuno, M.J.; Okparanma, R.N.; Nweneka, E.K.; Ogaji, S.O.T.; Probert, S.D.

2007-01-01

Bio-augmentation has been used as a bio-remediation option for hydrocarbon-contaminated, oily-sludge restoration. This sludge was obtained from the Bonny-Terminal Improvement Project (BTIP) for Bonny Island, near Port Harcourt, Nigeria. Its total hydrocarbon-content (THC) was 69,372 mg/kg of sludge. Three treatment reactors (X, Y and Z) and one control reactor (A) were charged with 1500 g of oily sludge and 250 g of agricultural soil (i.e. an oily sludge to soil ratio of 6:1), the mixture homogenized and allowed to settle for seven days before various CFUs were added to reactors X, Y and Z. Reactor A did not receive any bio-preparation. The agricultural soil served both as a nutrient and a microbe carrier. With regularly scheduled mixing and watering, the THC reduction in the oily sludge varied between 40.7% and 53.2% within two weeks as well as between 63.7% and 84.5% within six weeks of applying the bio-remediation. The CFU counts of the added bio-preparation varied between 1.2 x 12 12 and 3.0 x 10 12 CFU/g of sludge and decreased to 7.0 x 10 11 CFU/g of sludge by the end of the sixth week. The pH of the degrading sludge fluctuated between 6.5 and 7.8 during the same period. When compared with the performance of the indigenous microbes in the control sample, the added bio-preparation evidently increased the THC reduction rate in the oily sludge

ZnO template strategy for the synthesis of 3D interconnected graphene nanocapsules from coal tar pitch as supercapacitor electrode materials

Science.gov (United States)

He, Xiaojun; Li, Xiaojing; Ma, Hao; Han, Jiufeng; Zhang, Hao; Yu, Chang; Xiao, Nan; Qiu, Jieshan

2017-02-01

3D interconnected graphene nanocapsules (GNCs) were prepared from diverse aromatic hydrocarbons by a nano-ZnO-template strategy coupled with in-situ KOH activation technique. The as-made graphene networks feature thin carbonaceous shells with well-balanced micropores and mesopores. Such 3D porous networks provide freeways for good electron conduction, short pores for ion fast transport, and abundant micropores for ion adsorption. As the electrodes in supercapacitors, the unique 3D GNCs show a high capacitance of 277 F g-1 at 0.05 A g-1, a good rate performance of 194 F g-1 at 20 A g-1, and an excellent cycle stability with over 97.4% capacitance retention after 15000 cycles in 6 M KOH electrolyte. This synthesis strategy paves a universal way for mass production of 3D graphene materials from diverse aromatic hydrocarbon sources including coal tar pitch and petroleum pitch for high performance supercapacitors as well as support and sorbent.

Preparative radiation chemistry

International Nuclear Information System (INIS)

Drawe, H.

1978-01-01

Preparative synthesis of compounds with the aid of radiation chemistry is increasingly used in laboratories as well as on a technical scale. A large number of new compounds has been produced with the methods of radiation chemistry. With the increasing number of available radiation sources, also the number of synthesis metods in radiation chemistry has increased. This paper can only briefly mention the many possible ways of synthesis in radiation chemistry. (orig./HK) [de

Preparation of silver nanoparticles from synthetic and natural sources: remediation model for PAHs

International Nuclear Information System (INIS)

Abbasi, M.; Saeed, F.; Rafique, U.

2013-01-01

The emergence of nanoscience and technology is gaining popularity with an increasing demand for metal nanoparticles applicability in various areas such as electronics, catalysis, chemistry, energy and medicine. Metallic nanoparticles are traditionally synthesized by wet chemical techniques, where the chemicals used are quite often toxic and flammable. In this work, an attempt is made to compare the efficiency of two different synthesis methods and application of each for the remediation of poly aromatic hydrocarbons (PAHs). In this regard, silver nanoparticles are prepared by green and wet chemical method using plant extract of garlic (Allium sativum). The extract is known to reduce the metal during synthesis and acts as stabilizing ligand. These synthesized silver nanoparticles (Agp) and (AgW) were applied as adsorbents in synthetic batch mode experiments at varying parameters of pH and temperature. A concentration of 0.01mg/L of Phenanthrene, Anthracene, and Pyrene were induced at fixed dosage of 1mg/Kg of adsorbent. Residual concentration of each PAH was analyzed on UV-Visible spectrophotometer. The results indicated that both adsorbents follow the sequence of Phenanthrene>Pyrene>Anthracene with optimal removal of higher than 85 percentage in each case. A distinguishing privilege is attained by Agp adsorbent showing 3, 3 and 11 orders of magnitude higher efficiency than Agw. It may be attributed to more functional groups in the plant extract participating in binding of PAH to the surface. Each synthesized adsorbents was characterized by FTIR, SEM and EDX. The average particle size was determined to be of the order of 13-26 nm. The study concludes the use of alternate economical and green adsorbents for control of poly aromatic hydrocarbons (PAHs). (author)

Preparation of Silver Nanoparticles from Synthetic and Natural Sources: Remediation Model for PAHs

International Nuclear Information System (INIS)

Abbasi, Maryam; Saeed, Fatima; Rafique, Uzaira

2014-01-01

The emergence of nanoscience and technology is gaining popularity with an increasing demand for metal nanoparticles applicability in various areas such as electronics, catalysis, chemistry, energy and medicine. Metallic nanoparticles are traditionally synthesized by wet chemical techniques, where the chemicals used are quite often toxic and flammable. In this work, an attempt is made to compare the efficiency of two different synthesis methods and application of each for the remediation of poly aromatic hydrocarbons (PAHs). In this regard, silver nanoparticles are prepared by green and wet chemical method using plant extract of garlic (Allium sativum). The extract is known to reduce the metal during synthesis and acts as stabilizing ligand. These synthesized silver nanoparticles (Agp) and (AgW) were applied as adsorbents in synthetic batch mode experiments at varying parameters of pH and temperature. A concentration of 0.01mg/L of Phenanthrene, Anthracene, and Pyrene were induced at fixed dosage of 1mg/Kg of adsorbent. Residual concentration of each PAH was analyzed on UV-Visible spectrophotometer. The results indicated that both adsorbents follow the sequence of Phenanthrene>Pyrene>Anthracene with optimal removal of higher than 85% in each case. A distinguishing privilege is attained by Agp adsorbent showing 3, 3 and 11 orders of magnitude higher efficiency than Agw. It may be attributed to more functional groups in the plant extract participating in binding of PAH to the surface. Each synthesized adsorbents was characterized by FTIR, SEM and EDX. The average particle size was determined to be of the order of 13-26 nm. The study concludes the use of alternate economical and green adsorbents for control of poly aromatic hydrocarbons (PAHs)

Preparation of Silver Nanoparticles from Synthetic and Natural Sources: Remediation Model for PAHs

Science.gov (United States)

Abbasi, Maryam; Saeed, Fatima; Rafique, Uzaira

2014-06-01

The emergence of nanoscience and technology is gaining popularity with an increasing demand for metal nanoparticles applicability in various areas such as electronics, catalysis, chemistry, energy and medicine. Metallic nanoparticles are traditionally synthesized by wet chemical techniques, where the chemicals used are quite often toxic and flammable. In this work, an attempt is made to compare the efficiency of two different synthesis methods and application of each for the remediation of poly aromatic hydrocarbons (PAHs). In this regard, silver nanoparticles are prepared by green and wet chemical method using plant extract of garlic (Allium sativum). The extract is known to reduce the metal during synthesis and acts as stabilizing ligand. These synthesized silver nanoparticles (Agp) and (AgW) were applied as adsorbents in synthetic batch mode experiments at varying parameters of pH and temperature. A concentration of 0.01mg/L of Phenanthrene, Anthracene, and Pyrene were induced at fixed dosage of 1mg/Kg of adsorbent. Residual concentration of each PAH was analyzed on UV-Visible spectrophotometer. The results indicated that both adsorbents follow the sequence of Phenanthrene>Pyrene>Anthracene with optimal removal of higher than 85% in each case. A distinguishing privilege is attained by Agp adsorbent showing 3, 3 and 11 orders of magnitude higher efficiency than Agw. It may be attributed to more functional groups in the plant extract participating in binding of PAH to the surface. Each synthesized adsorbents was characterized by FTIR, SEM and EDX. The average particle size was determined to be of the order of 13-26 nm. The study concludes the use of alternate economical and green adsorbents for control of poly aromatic hydrocarbons (PAHs).

Preparation, characterization and catalytic application of CoFe2O4 nanoparticles in the synthesis of benzimidazoles

Science.gov (United States)

Borade, Ravikumar M.; Shinde, Pavan R.; Kale, Swati B.; Pawar, Rajendra P.

2018-05-01

A highly efficient magnetically recoverable cobalt ferrite nano-catalyst was prepared by sol-gel autocombustion method using glycine as green fuel. The prepared material has been characterized by X-ray powder diffraction and scanning. An investigation of its catalytic activity showed it to be a heterogeneous Lewis acid catalyst for the synthesis of substituted benzimidazoles. The aqueous ethanol used as green solvent for the reaction. The nm size range of these particles facilitates the catalysis process, as an increased surface area available for the reaction. The easy separation of the catalyst by an external magnet and their recovery and reuse in next cycle reaction are additional benefits.

Photoluminescence and cathodoluminescence properties of Y2O3:Eu nanophosphors prepared by combustion synthesis

International Nuclear Information System (INIS)

Vu, Nguyen; Kim Anh, Tran; Yi, Gyu-Chul; Strek, W.

2007-01-01

Eu-doped Y 2 O 3 nanophosphors were prepared using combustion synthesis. In this method, urea was employed as a fuel. The particle size was estimated to be in the range of 10-20 nm as determined by X-ray diffractometry and transmission electron microscopy. The photoluminescent and cathodoluminescent spectra are described by the well-known 5 D 0 →7 F J transition (J=0, 1, 2, etc.) of Eu 3+ ions with the strongest emission for J=2. The optical properties of nanophosphors were compared with commercial with an order of micrometer size. The effects of urea-to-metal nitrate molar ratio and the other synthesis conditions on the particle size and luminescent properties will be discussed in detail. The red emission of Eu-doped Y 2 O 3 nanophosphors is promising materials not only in high-resolution screen but also in telecomunication as well as in biosensor

Hydrocarbon phenotyping of algal species using pyrolysis-gas chromatography mass spectrometry

Directory of Open Access Journals (Sweden)

Kothari Shankar L

2010-05-01

Full Text Available Abstract Background Biofuels derived from algae biomass and algae lipids might reduce dependence on fossil fuels. Existing analytical techniques need to facilitate rapid characterization of algal species by phenotyping hydrocarbon-related constituents. Results In this study, we compared the hydrocarbon rich algae Botryococcus braunii against the photoautotrophic model algae Chlamydomonas reinhardtii using pyrolysis-gas chromatography quadrupole mass spectrometry (pyGC-MS. Sequences of up to 48 dried samples can be analyzed using pyGC-MS in an automated manner without any sample preparation. Chromatograms of 30-min run times are sufficient to profile pyrolysis products from C8 to C40 carbon chain length. The freely available software tools AMDIS and SpectConnect enables straightforward data processing. In Botryococcus samples, we identified fatty acids, vitamins, sterols and fatty acid esters and several long chain hydrocarbons. The algae species C. reinhardtii, B. braunii race A and B. braunii race B were readily discriminated using their hydrocarbon phenotypes. Substructure annotation and spectral clustering yielded network graphs of similar components for visual overviews of abundant and minor constituents. Conclusion Pyrolysis-GC-MS facilitates large scale screening of hydrocarbon phenotypes for comparisons of strain differences in algae or impact of altered growth and nutrient conditions.

Growth and biosurfactant synthesis by Nigerian hydrocarbon-degrading estuarine bacteria

Directory of Open Access Journals (Sweden)

Sunday A Adebusoye

2008-12-01

Full Text Available The ability of microorganisms to degrade petroleum hydrocarbons is important for finding an environmentally-friendly method to restoring contaminated environmental matrices. Screening of hydrocarbon-utilizing and biosurfactant-producing abilities of organisms from an estuarine ecosystem in Nigeria, Africa, resulted in the isolation of five microbial strains identified as Corynebacterium sp. DDv1, Flavobacterium sp. DDv2, Micrococcus roseus DDv3, Pseudomonas aeruginosa DDv4 and Saccharomyces cerevisae DDv5. These isolates grew readily on several hydrocarbons including hexadecane, dodecane, crude oil and petroleum fractions. Axenic cultures of the organisms utilized diesel oil (1.0 % v/v with generation times that ranged significantly (t-test, P La capacidad de los microorganismos para degradar hidrocarburos del petróleo es de gran importancia para hallar un método aceptable y ambientalmente amigable para la restauración de terrenos ambientalmente contaminados. Al investigar las capacidades de los organismos de un ecosistema de estuario que utilizan hidrocarburos y producen biosurfactantes, se produjo como resultado el aislamiento de cinco cepas microbianas identificadas como Corynebacterium sp. DDv1, Flavobacterium sp. DDv2, Micrococcus roseus DDv3, Pseudomonas aeruginosa y DDv4 Saccharomyces cerevisiae DDv5. Estas cepas crecieron fácilmente en varios hidrocarburos incluyendo hexadecanos, dodecanos, petróleo crudo y fracciones de petróleo. Los cultivos axénicos de organismos utilizaron diesel (1.0% v/v con períodos por generación con ámbitos significativos (t-test, P <0.05 de entre 3.25 y 3.88 días, con la consiguiente producción de bio-surfactantes. La cinética del crecimiento indica que la síntesis de bio-surfactante se produjo principalmente durante la fase de crecimiento exponencial, lo que sugiere que las moléculas bioactivas son metabolitos primarios. Las cepas DDv1 y DDv4 fueron evidentemente las más metab

Effect of structural promoters on Fe-based Fischer-Tropsch synthesis of biomass derived syngas

Science.gov (United States)

Pratibha Sharma; Thomas Elder; Leslie H. Groom; James J. Spivey

2014-01-01

Biomass gasification and subsequent conversion of this syngas to liquid hydrocarbons using Fischer–Tropsch (F–T) synthesis is a promising source of hydrocarbon fuels. However, biomass-derived syngas is different from syngas obtained from other sources such as steam reforming of methane. Specifically the H2/CO ratio is less than 1/1 and the CO

Total Synthesis of Marine Cyclic Enol-Phosphotriester Salinipostin Compounds

Science.gov (United States)

Zhao, Mingliang; Wei, Xianfeng; Liu, Xuemeng; Dong, Xueyang; Yu, Rilei; Wan, Shengbiao; Jiang, Tao

2018-06-01

Due to their structural diversity and variety of biological activities, marine natural products have been the subject of extensive study. These compounds, especially phospholipid polycyclic aromatic hydrocarbons, have a wide range of pharmacological applications, including embedded DNA and central nervous system, anti-tumor, anti-virus, anti-parasite, anti-bacterial, and antithrombotic effects. Unfortunately, the insufficient drug sources have limited the development of these compounds. In this study, we isolated salinpostin compounds from a fermentation solution of marine-derived Salinospora sp., which has a common bicyclic enol-phosphotriester core framework, as well as potent and selective antimalarial activities against P. falciparum with EC50 = 50 nmol L-1. The chemical synthesis of these compounds in greater quantities is necessary for their use in bioactivity studies. Thus we explored a short route with high yields and mild reaction conditions, which can generate combinatorial libraries for drug discovery and lead optimization. We developed a new total synthesis method for six cyclic enol-phosphotriester salinipotin compounds and their diastereomers. For the total synthesis of cyclipostin P, we prepared cyclic enol-phosphotriester salinipostin compounds in 10 steps from a readily accessible starting material, 1,3-dihydroxyacetone, and obtained an overall yield of 1.29%. We fully characterized these compounds by proton nuclear magnetic resonance (1H-NMR), carbon-13 NMR (13C-NMR), and high-resolution mass spectrometry (HRMS) analyses, and found they coincide absolutely with the same compounds reported previously.

Preparation of carbon-11 labelled phenylalanine and phenylglycine by a new amino acid synthesis

Energy Technology Data Exchange (ETDEWEB)

Vaalburg, W; Beerling-van der Molen, H D; Reiffers, S; Rijskamp, A; Woldring, M G; Wynberg, H [Academic Hospital, Groningen (Netherlands). Central Isotope Lab.

1976-03-01

Of the cyclotron-produced short-lived isotopes carbon-11 (tsub(1/2) = 20.4 min;..beta../sup +/) is one of the most promising as label for radiopharmaceuticals. To prepare /sup 11/C-labelled amino acids for evaluation as pancreas scanning agents a new rapid amino acid synthesis was developed. The method is based on the carboxylation of ..cap alpha..-lithioisocyanides with /sup 11/CO/sub 2/, followed by hydrolysis of the intermediate reaction product to the desired amino acid. By this method DL-..cap alpha..-phenylalanine-1-/sup 11/C and DL-..cap alpha..-phenylglycine-1-/sup 11/C were prepared. The precursor /sup 11/CO/sub 2/ was produced via the /sup 14/N(p,..cap alpha..)/sup 11/C reaction by bombardment of a flow of nitrogen gas mixed with 0.1% 0/sub 2/ with 20 MeV protons. The target system is described.

Spatial Distribution of Zeolite ZSM-5 within Catalyst Bodies Affects Selectivity and Stability of Methanol-to-Hydrocarbons Conversion

NARCIS (Netherlands)

Castaño, P.; Ruiz-Martinez, J.; Epelde, E.; Gayubo, A.G.; Weckhuysen, B.M.

2013-01-01

Solid acids, such as zeolites, are used as catalyst materials in a wide variety of important crude oil refinery, bulk chemical synthesis, and green processes. Examples include fluid catalytic cracking (FCC),[1] methanol-to-hydrocarbons (MTH) conversion,[ 2] plastic waste valorization,[3] and biomass

Effect of Manganese Promotion on Al-Pillared Montmorillonite Supported Cobalt Nanoparticles for Fischer-Tropsch Synthesis

International Nuclear Information System (INIS)

Ahmad, N.; Hussain, S. T.; Abbas, S. M.; Khan, Y.; Muhammad, B.; Ali, N.

2013-01-01

The effect of Mn-promotion on high surface area Al-pillared montmorillonite (AlMMT) supported Co nanoparticles prepared by hydrothermal method have been investigated. A series of different weight% Mn-promoted Co nanoparticles were prepared and characterized by XRD, TPR, TGA, BET and SEM techniques. An increase in the surface area of MMT is observed with Al-pillaring. Fischer-Tropsch catalytic activity of the as prepared catalysts was studied in a fixed bed micro reactor at 225 .deg. C, H 2 /CO = 2 and at 1 atm pressure. The data showed that by the addition of Mn the selectivity of C 1 dropped drastically while that of C 2 -C 12 hydrocarbons increased significantly over all the Mn-promoted Co/AlMMT catalysts. The C 13 -C 20 hydrocarbons remained almost same for all the catalysts while the selectivity of C 21+ long chain hydrocarbons decreased considerably with the addition of Mn. The catalyst with 3.5%Mn showed lowest C 21+ and highest C 2 -C 12 hydrocarbons selectivity due to cracking of long chain hydrocarbons over acidic sites of MMT

Synthesis and studies of Y-Ba-Cu-O high temperature superconductor prepared by sol-gel method

International Nuclear Information System (INIS)

Grigoryan, S.G.; Manukyan, A.L.; Hayrapetyan, A.G.; Arzumanyan, A.M.; Rashidyan, L.H.; Mkrtichyan, N.Y.; Mkrtchyan, A.A.; Kurginyan, K.A.; Trozyan, A.H.; Vardanyan, R.S.

2004-01-01

The method of preparation of Y-Ba-Cu-O high temperature superconducting materials by sol-gel processing technique both for powders and thin films are described. All these methods are based on using yttrium alkoxides as precursors, which are not ready available reagents, besides the majority of these methods use copper alkoxides, which show low solubility in organic solvents, moreover they are very sensitive to hydrolysis in air. The new method of preparation of Y-Ba-Cu-O ceramic materials by sol-gel processing technique based on new and convenient precursors stable in air, having high compatibility with each other is offered. Basic scientific and technological issues related to the synthesis of bulk materials, their structure and electrical conductivity are discussed

Process for the preparation of lubricants

Energy Technology Data Exchange (ETDEWEB)

Pier, M

1927-06-04

A process is described for preparation of lubricants from mixtures of hydrocarbons or hydrocarbon derivatives of mean molecular weight and nonaromatic nature, which is characterized by halogenating the raw oil by the action of halogens or halogen-exchanging compounds and submitting the obtained product to a condensation in presence of aluminum chloride, tin chloride, iron chloride, or other condensing metal chloride or boron fluoride or activated metals, such as activated aluminum, whereby it is worked up in two steps at a temperature below 150 and preferably below 100/sup 0/C.

Process and catalysts for hydrocarbon conversion. [high antiknock motor fuel

Energy Technology Data Exchange (ETDEWEB)

1940-02-14

High anti-knock motor fuel is produced from hydrocarbons by subjecting it at an elevated temperature to contact with a calcined mixture of hydrated silica, hydrated alumina, and hydrated zirconia, substantially free from alkali metal compounds. The catalyst may be prepared by precipitating silica gel by the acidification of an aqueous solution of an alkali metal silicate, intimately mixing hydrated alumina and hydrated zirconia therewith, drying, purifying the composite to substantially remove alkali metal compounds, again drying, forming the dried material into particles, and finally calcining. The resultant conversion products may be fractionated to produce gasoline, hydrocarbon oil above gasoling boiling point range, and a gaseous fraction of olefins which are polymerized into gasoline boiling range polymers.

Distribution of hydrocarbon-utilizing microorganisms and hydrocarbon biodegradation potentials in Alaskan continental shelf areas

International Nuclear Information System (INIS)

Roubal, G.; Atlas, R.M.

1978-01-01

Hydrocarbon-utilizing microogranisms were enumerated from Alaskan continental shelf areas by using plate counts and a new most-probable-number procedure based on mineralization of 14 C-labeled hydrocarbons. Hydrocarbon utilizers were ubiquitously distributed, with no significant overall concentration differences between sampling regions or between surface water and sediment samples. There were, however, significant seasonal differences in numbers of hydrocarbon utilizers. Distribution of hydrocarbon utilizers within Cook Inlet was positively correlated with occurrence of hydrocarbons in the environment. Hydrocarbon biodegradation potentials were measured by using 14 C-radiolabeled hydrocarbon-spiked crude oil. There was no significant correlation between numbers of hydrocarbon utilizers and hydrocarbon biodegradation potentials. The biodegradation potentials showed large seasonal variations in the Beaufort Sea, probably due to seasonal depletion of available nutrients. Non-nutrient-limited biodegradation potentials followed the order hexadecane > naphthalene >> pristane > benzanthracene. In Cook Inlet, biodegradation potentials for hexadecane and naphthalene were dependent on availability of inorganic nutrients. Biodegradation potentials for pristane and benzanthracene were restricted, probably by resistance to attack by available enzymes in the indigenous population

Synthesis and characterization of 2D graphene sheets from graphite powder

Science.gov (United States)

Patel, Rakesh V.; Patel, R. H.; Chaki, S. H.

2018-05-01

Graphene is 2D material composed of one atom thick hexagonal layer. This material has attracted great attention among scientific community because of its high surface area, excellent mechanical properties and conductivity due to free electrons in the 2D lattice. There are various approaches to prepare graphene nanosheets such as top-down approach where graphite exfoliation and nanotube unwrapping can be done. The bottom up approach involves deposition of hydrocarbon through CVD, epitaxial method and organo-synthesis etc.. In present studies top down approach method was used to prepare graphene. The graphite powder with around 20 µm to 150µm particle size was subjected to concentrated strong acid in presence of strong oxidizing agent in order to increase the d-spacing between layers which leads to the disruption of crystal lattice as confirmed by XRD (X'pert Philips). FT Raman spectra taken via (Renishaw InVia microscope) of pristine powder and Graphene oxide revealed the increase in D-band and reduction in G-Band. These exfoliated sheets have oxygen rich complexes at the surface of the layers as characterised by FTIR technique. The GO powder was ultrasonicated to prepare the stable suspension of Graphene. The graphene layers were observed under TEM (Philips Tecnai 20) as 2dimensional sheets with around 1µm sizes.

Plasma devices for hydrocarbon reformation

KAUST Repository

Cha, Min Suk

2017-02-16

Plasma devices for hydrocarbon reformation are provided. Methods of using the devices for hydrocarbon reformation are also provided. The devices can include a liquid container to receive a hydrocarbon source, and a plasma torch configured to be submerged in the liquid. The plasma plume from the plasma torch can cause reformation of the hydrocarbon. The device can use a variety of plasma torches that can be arranged in a variety of positions in the liquid container. The devices can be used for the reformation of gaseous hydrocarbons and/or liquid hydrocarbons. The reformation can produce methane, lower hydrocarbons, higher hydrocarbons, hydrogen gas, water, carbon dioxide, carbon monoxide, or a combination thereof.

On the Synthesis of Carbon Nanotubes from Waste Solid Hydrocarbons

Science.gov (United States)

Zhuo, Chuanwei

Carbon nanotubes (CNTs) are allotropes of carbon with a cylindrical nanostructure. They consist of coaxial tubular graphene sheets, with diameters in the order of nanometers (1 x 10-9 m) and lengths in the order of micrometers (1 x 10-6 m). The latter can now be extended into the order of meters. Carbon nanotubes (CNTs) have been studied for more than 20 years. CNTs possess superior electrical, mechanical, thermal, chemical, and structural properties, which make their potential applications nowadays overwhelmingly widespread. Now entering into the growth phase of product life cycle, increasing usage of CNTs in commercial products is part of the beginning of the nano-technological revolution. Expanding markets for CNTs' large volume applications place ever-increasing demands on lowering their production costs to the level acceptable by the end-user applications. It is estimated that the mass application of CNTs will be facilitated only when the price of CNTs approaches that of conductive carbon black. The synthesis of CNTs involves three elements: the carbonaceous feedstocks (raw materials), the catalysts, and the necessary process power consumption. Therefore, they jointly contribute to the major operation expenditures in CNT synthesis/production. Current technologies for large-scale production of CNTs (either chemical vapor deposition, CVD, or combustion synthesis) require intensive consumption of premium feedstocks and catalysts, and the CVD process requires high energy consumption. Therefore, there is a pressing need for resource-benign and energy-benign, cost-effective nano-manufacturing processes. In the search for sustainable alternatives, it would be prudent to explore renewable and/or replenishable low-cost feedstocks, such as those found in municipal, industrial, and agricultural recycling streams. In the search for low cost catalysts, stainless steels have been proposed as cost-effective dual purpose substrates and catalysts, as they contain transition

Preparation of Peleted Ni-Pt/Zeolite for Conversion of Amyl and Isoamyl Alcohol to Hydrocarbon

Directory of Open Access Journals (Sweden)

Abdullah Abdullah

2010-06-01

Full Text Available Catalysts with Ni and Pt as active metals in peleted zeolite were used for conversion of amyl alcohol, isoamyl alcohol and their mixture to hydrocarbon compounds. The catalysts were prepared by impregnation the peleted zeolite in NiCl2.6H2O and PtCI4 solution, while stirring for 24 hours then followed by oxidation with 02 gas at 350 °C for 2 hours and reduced by hydrogen gas at 400 °C for 1 hour. Ni and Pt in catalysts were determined by MS, specific surface area, total pore volume and gas sorption analyzer NOVA-1000 determined pore radius average. Determination of catalysts acidity was carried out by absorption of ammonia method. The activity of catalysts was evaluated in a micro reactor by flow system. Experimental temperature by varied between 300 and 400 °C with the increment of 25 °C. Products were analyzed by gas chromatographic and mass spectrometric method. The result shows that Ni-Pt/zeolite is more active than Ni/zeolite can be used for converting all of the alcohol. Products for conversion are 2-pentene, 2-methyl-1-butene, 2-methyl-2-butene, cyclopentane, 3-methyl-1-butanaldehide and acetone. The highest conversion was observed on isoamyl alcohol (31.37% at 400 °C.

Endophytic Bacteria Associated with Hieracium piloselloides: Their Potential for Hydrocarbon-Utilizing and Plant Growth-Promotion.

Science.gov (United States)

Pawlik, Małgorzata; Piotrowska-Seget, Zofia

2015-01-01

The aim of this study was to assess the potential of 18 crude-oil-degrading endophytic bacteria for removal of hydrocarbons and promotion of plant growth. Strains were isolated from Hieracium piloselloides (tall hawkweed), which grows in soil heavily polluted with petroleum hydrocarbons. Bacteria from the genus Pseudomonas were abundant among the isolates. The potential for hydrocarbon degradation was evaluated by polymerase chain reaction (PCR) analyses of the genes alkB, alkH, C23O, P450, and pah. It was found that 88.89% of the endophytic bacteria contained gene-encoding polycyclic aromatic hydrocarbon (PAH) initial dioxygenase, 61% possessed the 2,3-catechol dioxygenase gene, and 39% of strains that were tested had the cytochrome P-450 hydroxylase gene. All isolates were capable of producing indole-3-acetic acid (1.8-76.4 μg/ml). Only 17% of them were able to produce siderophores, excrete cellulase, and solubilize phosphate. Hydrogen cyanide synthesis occurred in 33% of endophytic bacteria. The 1-aminocyclopropane-1-carboxylate deaminase activity in isolates that were screened was in the range of 2.6 to 74.1 μmol α-ketobutyrate/mg/h. This feature of the bacteria indicated that isolates may enhance the phytoremediation process. Data suggest that crude-oil-degrading endophytic bacteria possess potential to be promising candidates for enhancement of phytoremediation of hydrocarbon-contaminated soil. Further evaluation of these bacteria is needed in order to assess the role played in the degradation of petroleum hydrocarbons.

Preparation of mesoporous MnO2/C catalyst for n-hexyl acetate synthesis

International Nuclear Information System (INIS)

Yang Zeheng; Pan Yanmei; Mei Zhousheng; Zhang Weixin

2012-01-01

A mesoporous MnO 2 /C composite was prepared by impregnating self-made porous carbon spheres with manganese nitrate aqueous solution and subsequently reacting with KMnO 4 aqueous solution. It was characterized with X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), the Brunauer-Emmett-Teller (BET) surface area and the Barrett-Joyner-Halenda (BJH) pore size distribution. The as-prepared mesoporous MnO 2 /C composite was used as catalyst for the synthesis of n-hexyl acetate, and the effects of MnO 2 loading and esterification reaction parameters on the esterification rate were investigated. The results prove that MnO 2 loading has a significant effect on the catalytic activity and that the mesoporous MnO 2 /C composite exhibits high catalytic activity with an esterification rate of 96.42% under the conditions below: MnO 2 loading (73.09 wt%), catalyst dosage (0.1% in total weight), acetic acid/n-hexanol molar ratio (2:1), reaction temperature (130 °C) and reaction time (5 h).

Contact angles at the water-air interface of hydrocarbon-contaminated soils and clay minerals

Science.gov (United States)

Sofinskaya, O. A.; Kosterin, A. V.; Kosterina, E. A.

2016-12-01

Contact angles at the water-air interface have been measured for triturated preparations of clays and soils in order to assess changes in their hydrophobic properties under the effect of oil hydrocarbons. Tasks have been to determine the dynamics of contact angle under soil wetting conditions and to reveal the effect of chemical removal of organic matter from soils on the hydrophilicity of preparations. The potentialities of static and dynamic drop tests for assessing the hydrophilic-hydrophobic properties of soils have been estimated. Clays (kaolinite, gumbrine, and argillite) have been investigated, as well as plow horizons of soils from the Republic of Tatarstan: heavy loamy leached chernozem, medium loamy dark gray forest soil, and light loamy soddy-calcareous soil. The soils have been contaminated with raw oil and kerosene at rates of 0.1-3 wt %. In the uncontaminated and contaminated chernozem, capillary water capacity has been maintained for 250 days. The contact angles have been found to depend on the degree of dispersion of powdered preparation, the main type of clay minerals in the soil, the presence and amount of oxidation-resistant soil organic matter, and the soil-water contact time. Characteristic parameters of mathematical models for drop behavior on triturated preparations have been calculated. Contamination with hydrocarbons has resulted in a reliable increase in the contact angles of soil preparations. The hydrophobization of soil surface in chernozem is more active than in soils poorer in organic matter. The complete restoration of the hydrophilic properties of soils after hydrocarbon contamination is due to the oxidation of easily oxidizable organic matter at the low content of humus, or to wetting during several months in the absence of the mazut fraction.

Petroleum hydrocarbons

International Nuclear Information System (INIS)

Farrington, J.W.; Teal, J.M.; Parker, P.L.

1976-01-01

Methods for analysis of petroleum hydrocarbons in marine samples are presented. Types of hydrocarbons present and their origins are discussed. Principles and methods of analysis are outlined. Infrared spectrometry, uv spectrometry, gas chromatography, mass spectroscopy, and carbon 14 measurements are described

Tuneable light-emitting carbon-dot/polymer flexible films prepared through one-pot synthesis

Science.gov (United States)

Bhunia, Susanta Kumar; Nandi, Sukhendu; Shikler, Rafi; Jelinek, Raz

2016-02-01

Development of efficient, inexpensive, and environmentally-friendly light emitters, particularly devices that produce white light, have drawn intense interest due to diverse applications in the lighting industry, photonics, solar energy, and others. We present a simple strategy for the fabrication of flexible transparent films exhibiting tuneable light emission through one-pot synthesis of polymer matrixes with embedded carbon dots assembled in situ. Importantly, different luminescence colours were produced simply by preparing C-dot/polymer films using carbon precursors that yielded C-dots exhibiting distinct fluorescence emission profiles. Furthermore, mixtures of C-dot precursors could be also employed for fabricating films exhibiting different colours. In particular, we successfully produced films emitting white light with attractive properties (i.e. ``warm'' white light with a high colour rendering index) - a highly sought after goal in optical technologies.Development of efficient, inexpensive, and environmentally-friendly light emitters, particularly devices that produce white light, have drawn intense interest due to diverse applications in the lighting industry, photonics, solar energy, and others. We present a simple strategy for the fabrication of flexible transparent films exhibiting tuneable light emission through one-pot synthesis of polymer matrixes with embedded carbon dots assembled in situ. Importantly, different luminescence colours were produced simply by preparing C-dot/polymer films using carbon precursors that yielded C-dots exhibiting distinct fluorescence emission profiles. Furthermore, mixtures of C-dot precursors could be also employed for fabricating films exhibiting different colours. In particular, we successfully produced films emitting white light with attractive properties (i.e. ``warm'' white light with a high colour rendering index) - a highly sought after goal in optical technologies. Electronic supplementary information (ESI

Simulation of the Dynamics of Isothermal Growth of Single-Layer Graphene on a Copper Catalyst in the Process of Chemical Vapor Deposition of Hydrocarbons

Science.gov (United States)

Futko, S. I.; Shulitskii, B. G.; Labunov, V. A.; Ermolaeva, E. M.

2018-01-01

A new kinetic model of isothermal growth of single-layer graphene on a copper catalyst as a result of the chemical vapor deposition of hydrocarbons on it at a low pressure has been developed on the basis of in situ measurements of the growth of graphene in the process of its synthesis. This model defines the synthesis of graphene with regard for the chemisorption and catalytic decomposition of ethylene on the surface of a copper catalyst, the diffusion of carbon atoms in the radial direction to the nucleation centers within the thin melted near-surface copper layer, and the nucleation and autocatalytic growth of graphene domains. It is shown that the time dependence of the rate of growth of a graphene domain has a characteristic asymmetrical bell-like shape. The dependences of the surface area and size of a graphene domain and the rate of its growth on the time at different synthesis temperatures and ethylene concentrations have been obtained. Time characteristics of the growth of graphene domains depending on the parameters of their synthesis were calculated. The results obtained can be used for determining optimum regimes of synthesis of graphene in the process of chemical vapor deposition of hydrocarbons on different catalysts with a low solubility of carbon.

Preparation of Ultra Low-κ Porous SiOCH Films from Ring-Type Siloxane with Unsaturated Hydrocarbon Side Chains by Spin-On Deposition

International Nuclear Information System (INIS)

Chun-Xiao, Yang; Chi, Zhang; Qing-Qing, Sun; Sai-Sheng, Xu; Li-Feng, Zhang; Yu, Shi; Shi-Jin, Ding; Wei, Zhang

2010-01-01

An ultra-low-dielectric-constant (ultra low-k, or ULK) porous SiOCH film is prepared using a single ring-type siloxane precursor of the 2,4,6,8-tetravinyl-2,4,6,8-tetramethylcyclotetrasiloxane by means of spin-on deposition, followed by crosslinking reactions between the precursor monomers under UV irradiation. The as-prepared film has an ultra low k of 2.41 at 1 MHz due to incorporation of pores and hydrocarbon crosslinkages, a leakage current density of 9.86 × 10 −7 A/cm 2 at 1 MV/cm, as well as a breakdown field strength of ∼1.5 MV/cm. Further, annealing at 300°C results in lower k (i.e., 1.94 at 1 MHz), smaller leakage current density (2.96 × 10 −7 A/cm 2 at 1 MV/cm) and higher breakdown field strength (about 3.5 MV/cm), which are likely caused by the short-ranged structural rearrangement and reduction of defects in the film. Finally, the mechanical properties and surface morphology of films are also evaluated after different temperature annealing. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

Reactivity of organic compounds in catalytic synthesis

Energy Technology Data Exchange (ETDEWEB)

Minachev, Kh M; Bragin, O V

1978-01-01

A comprehensive review of 1976 Soviet research on catalysis delivered to the 1977 annual session of the USSR Academy of Science Council on Catalysis (Baku 6/16-20/77) covers hydrocarbon reactions, including hydrogenation and hydrogenolysis, dehydrogenation, olefin dimerization and disproportionation, and cyclization and dehydrocyclization (e.g., piperylene cyclization and ethylene cyclotrimerization); catalytic and physicochemical properties of zeolites, including cracking, dehydrogenation, and hydroisomerization catalytic syntheses and conversion of heterocyclic and functional hydrocarbon derivatives, including partial and total oxidation (e.g., of o-xylene to phthalic anhydride); syntheses of thiophenes from alkanes and hydrogen sulfide over certain dehydrogenation catalysts; catalytic syntheses involving carbon oxides ( e.g., the development of a new heterogeneous catalyst for hydroformylation of olefins), and of Co-MgO zeolitic catalysts for synthesis of aliphatic hydrocarbons from carbon dioxide and hydrogen, and fabrication of high-viscosity lubricating oils over bifunctional aluminosilicate catalysts.

Synthesis and properties of nasicon prepared from different zirconia-based precursors

Directory of Open Access Journals (Sweden)

Fuentes, R. O.

1999-12-01

Full Text Available This work reports on the synthesis and characterization of NASICON prepared from SiO2, Na3PO4.12H2O and two types of zirconia: pure monoclinic ZrO2 and TZP (Tetragonal Polycrystalline Zirconia, with 3 mol% Y2O3 as raw materials. The classical ceramic method was used in all cases. SEM, XRD and DTA were used to follow the synthesis and sintering process, and impedance spectroscopy (IS was used to study the electrical properties of sintered pellets. Results obtained with different NASICON samples showed a significant role of composition and processing conditions on the electrical properties. Samples based on TZP, sintered at 1210ºC, exhibited densities of about 3.20 g/cm3 (98% of theoretical density of NASICON and ionic conductivities of about 2x10-3 S.cm-1 at room temperature a rather interesting result when compared with data obtained with the material prepared from pure ZrO2.

Este trabajo trata de la síntesis y caracterización de NASICON preparado a partir de SiO2 , Na3PO4.12H2O y dos tipos de circonia, ZrO2 monoclínica pura y TZP (circonia policristalina tetragonal, con 3 moles% Y2O3 como materia prima. Se emplea el método cerámico clásico en todos los casos. Las técnicas de MEB, DRX y ATD se emplean para seguir la síntesis y el proceso de sinterización. La espectroscopia de impedancia compleja se emplea para estudiar las propiedades eléctricas de las muestras sinterizadas. Los resultados obtenidos con diferentes muestras de NASICON mostraron un papel significativo de la composición y condiciones de procesamiento sobre las propiedades eléctricas. Las muestras basadas en TZP, sinterizadas a 1210ºC, presentan densidades alrededor de 3.20 g/cm3 (98% de la densidad teórica del NASICON y conductividad iónica de 2x 10-3 5.cm-1 a temperatura ambiente, un resultado bastante interesante cuando se compara con datos obtenidos con material preparado de ZrO2 pura.

Converting high boiling hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Terrisse, H; DuFour, L

1929-02-12

A process is given for converting high boiling hydrocarbons into low boiling hydrocarbons, characterized in that the high boiling hydrocarbons are heated to 200 to 500/sup 0/C in the presence of ferrous chloride and of such gases as hydrogen, water gas, and the like gases under a pressure of from 5 to 40 kilograms per square centimeter. The desulfurization of the hydrocarbons occurs simultaneously.

Synthesis mechanism of an Al-Ti-C grain refiner master alloy prepared by a new method

Science.gov (United States)

Zhang, B. Q.; Lu, L.; Lai, M. O.; Fang, H. S.; Ma, H. T.; Li, J. G.

2003-08-01

The mechanisms of in-situ synthesis of an Al-Ti-C grain-refiner master alloy, prepared by adding a powder mixture of potassium titanium fluoride and carbon into an aluminum melt, have been systematically studied. It was found that vigorous reactions occurred at the initial stage of reaction and then slowed down. After about 20 minutes, the reactions, which led the formation of blocky titanium aluminides and submicron titanium carbides in the aluminum matrix, appeared to reach completion. Potassium titanium fluoride reacted with aluminum and carbon at 724 °C and 736 °C, respectively, resulting in the formation of titanium aluminides and titanium carbides in the aluminum matrix as well as in the formation of a low-melting-point slag of binary potassium aluminofluorides. The reaction between potassium titanium fluoride and carbon is believed to be the predominant mechanism in the synthesis of TiC by this method.

The synthesis of higher alcohols from CO2 hydrogenation with Co, Cu, Fe-based catalysts

International Nuclear Information System (INIS)

Ji, Qinqin

2017-01-01

CO 2 is a clean carbon source for the chemical reactions, many researchers have studied the utilization of CO 2 . Higher alcohols are clean fuel additives. The synthesis of higher alcohols from CO hydrogenation has also been studied by many researchers, but there are few literatures about the synthesis of higher alcohols from CO 2 hydrogenation, which is a complex and difficult reaction. The catalysts that used for higher alcohols synthesis need at least two active phases and good cooperation. In our study, we tested the Co. Cu. Fe spinel-based catalysts and the effect of supports (CNTs and TUD-1) and promoters (K, Na, Cs) to the HAS reaction. We found that catalyst CuFe-precursor-800 is beneficial for the synthesis of C2+ hydrocarbons and higher alcohols. In the CO 2 hydrogenation, Co acts as a methanation catalyst rather than acting as a FT catalyst, because of the different reaction mechanism between CO hydrogenation and CO 2 hydrogenation. In order to inhibit the formation of huge amount of hydrocarbons, it is better to choose catalysts without Co in the CO 2 hydrogenation reaction. Compared the functions of CNTs and TUD-1, we found that CNTs is a perfect support for the synthesis of long-chain products (higher alcohols and C2+ hydrocarbons). The TUD-1 support are more suitable for synthesis of single-carbon products (methane and methanol).The addition of alkalis as promoters does not only lead to increase the conversion of CO 2 and H 2 , but also sharply increased the selectivity to the desired products, higher alcohols. The catalyst 0.5K30CuFeCNTs owns the highest productivities (370.7 g.kg -1 .h -1 ) of higher alcohols at 350 C and 50 bar. (author) [fr

Optical filtering and luminescence property of some molybdates prepared by combustion synthesis

Energy Technology Data Exchange (ETDEWEB)

Yadav, P. J., E-mail: yadav.pooja75@yahoo.in [Department of Electronics, RTM Nagpur University, Nagpur (India); Joshi, C. P. [Physics Department, RCOEM, Nagpur (India); Moharil, S. V., E-mail: svmoharil@yahoo.com [Physics Department, RTM Nagpur University, Nagpur (India)

2014-10-15

As an important class of lanthanide inorganic compounds, rare earth ions doped molybdates have gained much attention due to their attractive luminescence and structural properties, supporting various promising applications as phosphor materials in the fields such as white light-emitting diodes, optical fibers, biolabel, lasers, and so on. The molybdate family has promising trivalent cation conducting properties and most of the optical properties result from electron transitions of the 4f shell, which are greatly affected by the composition and structures of rare-earth compounds. In this paper we report the molybdate CaMoO{sub 4}:Eu{sup 3+} for red SSL and Bi{sub 1.4}Y{sub 0.6}MoO{sub 6}, Y{sub 6}MoO{sub 12} for optical filtering, prepared by one step combustion synthesis.

Synthesis of amino-functionalized silica nanoparticles for preparation of new laboratory standards

Science.gov (United States)

Alvarez-Toral, Aitor; Fernández, Beatriz; Malherbe, Julien; Claverie, Fanny; Pecheyran, Christophe; Pereiro, Rosario

2017-12-01

Platinum group elements (PGEs) are particularly interesting analytes in different fields, including environmental samples as well as high cost materials that contain them, such as for example automotive catalysts. This type of solid samples could be analysed by laser ablation (LA) coupled to ICP-MS, which allow to significantly reducing the analysis time since the time-consuming processes for sample preparation are not required. There is a considerable demand of standards with high PGEs concentration for quantification purposes, which cannot be carried out easily using LA-ICP-MS because the available standards (i.e. NIST SRM 61 × series) do not have such analytes in the same concentration range. In this paper, a new strategy is proposed for the synthesis of homogeneous laboratory standards with Pt, Pd and Rh concentrations that range from 77 μg/g of Pd up to 2035 μg/g of Rh. The proposed strategy is based on the synthesis of monodisperse amino-functionalized amorphous silica nanoparticles, which can retain metal ions. In addition to Pt, Pd and Rh, three lanthanides were also added to the nanoparticles (La, Ce, Nd). Sturdy pressed pellets can be made from the resulting nanopowder without the use of any binder. Elemental composition of standards made of nanoparticles was analysed by conventional nebulization ICP-MS and their homogeneity was successfully evaluated by LA-ICP-MS.

Steady-state and transient hydrocarbon production in graphite by low energy impact of atomic and molecular deuterium projectiles

International Nuclear Information System (INIS)

Zhang, H.; Meyer, F.W.

2009-01-01

We report measurements of steady-state yields of methyl, methane and heavier hydrocarbons for deuterium atomic and molecular ions incident on ATJ graphite, HOPG, and a-C:D thin films in the energy range 10-200 eV/D. The yields were determined using a QMS technique in conjunction with calibrated hydrocarbon leaks. We have also studied transient hydrocarbon production and hydrogen (deuterium) re-emission for 80 and 150 eV/D D + , D 2 + , and D 3 + projectiles incident on ATJ graphite surfaces pre-loaded to steady state by 20 eV/D beams of the corresponding species. Immediately after starting the higher-energy beams, transient hydrocarbon and D 2 re-emission yields significantly larger than steady-state values were observed, which exponentially decayed as a function of beam fluence. The initial yield values were related to the starting hydrocarbon and deuterium densities in the prepared sample, while the exponential decay constants provided information on the hydrocarbon kinetic release and hydrogen (deuterium) detrapping cross-sections.

Engineering isoprene synthesis in cyanobacteria.

Science.gov (United States)

Chaves, Julie E; Melis, Anastasios

2018-04-24

The renewable production of isoprene (Isp) hydrocarbons, to serve as fuel and synthetic chemistry feedstock, has attracted interest in the field recently. Isp (C 5 H 8 ) is naturally produced from sunlight, CO 2 and H 2 O photosynthetically in terrestrial plant chloroplasts via the terpenoid biosynthetic pathway and emitted in the atmosphere as a response to heat stress. Efforts to institute a high capacity continuous and renewable process have included heterologous expression of the Isp synthesis pathway in photosynthetic microorganisms. This review examines the premise and promise emanating from this relatively new research effort. Also examined are the metabolic engineering approaches applied in the quest of renewable Isp hydrocarbons production, the progress achieved so far, and barriers encountered along the way. © 2018 Federation of European Biochemical Societies.

Production of hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Day, D T; Day, R E

1920-04-27

A process is disclosed of converting hydro-carbon oils having high boiling points to hydro-carbon oils having low boiling points, which process comprises adding the oil to be treated to a mass of hydro-carbon oil bearing shale, passing the shale with the oil through a conveyor retort and subjecting the material while in the retort to a heat treatment involving a temperature of at least 500/sup 0/F.

1992 Progress report on sediment-related aspects of northern hydrocarbon development

Energy Technology Data Exchange (ETDEWEB)

1993-01-01

The Mackenzie Delta is ecologically important for its outflow of warm, sediment-laden water to the Arctic Ocean. Lack of knowledge and clear understanding of delta processes raise serious concerns over potential impacts from development of local hydrocarbon resources on Delta ecosystems. The Northern Oil and Gas Program is sponsoring research on Mackenzie Delta hydrology and hydraulics, sediment flux, contaminant levels, and other issues relevant to impacts of hydrocarbon development. A compendium of five reports on the sediment-related aspects of this research is presented. The topics of the reports are: suspended sediment sampling; sedimentation measurement; channel stability; hydraulic and morphologic surveys; and sediment station data. A separate abstract has been prepared for each of the five reports.

Preparation of porous Al2O3-Ti-C perform by combustion synthesis

Directory of Open Access Journals (Sweden)

K.Granat

2009-04-01

Full Text Available Using combustion synthesis porous ceramic preforms for composite reinforcing were produced. Prepared mixture of alumina Saffilfibres, Ti powder and graphite flakes, after drying were placed in waveguide of microwave reactor. Supplied with constant power of 540Wmagnetron ignited and maintained reaction in flowing stream of CO2 gas. Al2O3 fibres should improve preliminary endurance of perform,whereas Ti powder processed to hard titanium carbides and oxides. During microwave heating ignited plasma additionally improveprocess and partly fused metallic Ti. Recorded temperature curves were similar for various samples. The highest synthesis temperature revealed samples containing 10% of Al2O3 , 10% of Ti and 5% of graphite, all percentages atomic. Microscopic observation showed considerable microstructure inhomogeneity of some samples. Both irregular component ordering and partly processed Ti particles inside preform exclude them for subsequent infiltration. Chemical analyze EDS of Ti based compounds partly confirmed work purpose, evidencing presence of Ti oxides and carbides. Independently of graphite content these compounds formed folded strips around solid or empty volume. Depends on CO2 availability, reaction could be slowed down resulting in more compacted Ti compounds. Created as a result of combustion synthesis Ti compound after infiltration with liquid metal properly bounded with the matrix. It could be assumed that redox reaction proceeded and on surface of Ti compound alumina and Al-Ti compounds were created. The preforms of proper strength and homogeneous structure were infiltrated with AlSi7Mg by squeeze casting method. In relation to typical composite reinforced only with fibres no significant increase of defects quantity was observed. Preliminary examination of mechanical properties confirmed that assumed work purpose is reasonable.

Hydrocarbon analysis using desorption atmospheric pressure chemical ionization

KAUST Repository

Jjunju, Fred Paul Mark; Badu-Tawiah, Abraham K.; Li, Anyin; Soparawalla, Santosh; Roqan, Iman S.; Cooks, Robert Graham

2013-01-01

Characterization of the various petroleum constituents (hydronaphthalenes, thiophenes, alkyl substituted benzenes, pyridines, fluorenes, and polycyclic aromatic hydrocarbons) was achieved under ambient conditions without sample preparation by desorption atmospheric pressure chemical ionization (DAPCI). Conditions were chosen for the DAPCI experiments to control whether ionization was by proton or electron transfer. The protonated molecule [M+H]+ and the hydride abstracted [MH]+ form were observed when using an inert gas, typically nitrogen, to direct a lightly ionized plasma generated by corona discharge onto the sample surface in air. The abundant water cluster ions generated in this experiment react with condensed-phase functionalized hydrocarbon model compounds and their mixtures at or near the sample surface. On the other hand, when naphthalene was doped into the DAPCI gas stream, its radical cation served as a charge exchange reagent, yielding molecular radical cations (M+) of the hydrocarbons. This mode of sample ionization provided mass spectra with better signal/noise ratios and without unwanted side-products. It also extended the applicability of DAPCI to petroleum constituents which could not be analyzed through proton transfer (e.g., higher molecular PAHs such as chrysene). The thermochemistry governing the individual ionization processes is discussed and a desorption/ionization mechanism is inferred. © 2012 Elsevier B.V.

Hydrocarbon analysis using desorption atmospheric pressure chemical ionization

KAUST Repository

Jjunju, Fred Paul Mark

2013-07-01

Characterization of the various petroleum constituents (hydronaphthalenes, thiophenes, alkyl substituted benzenes, pyridines, fluorenes, and polycyclic aromatic hydrocarbons) was achieved under ambient conditions without sample preparation by desorption atmospheric pressure chemical ionization (DAPCI). Conditions were chosen for the DAPCI experiments to control whether ionization was by proton or electron transfer. The protonated molecule [M+H]+ and the hydride abstracted [MH]+ form were observed when using an inert gas, typically nitrogen, to direct a lightly ionized plasma generated by corona discharge onto the sample surface in air. The abundant water cluster ions generated in this experiment react with condensed-phase functionalized hydrocarbon model compounds and their mixtures at or near the sample surface. On the other hand, when naphthalene was doped into the DAPCI gas stream, its radical cation served as a charge exchange reagent, yielding molecular radical cations (M+) of the hydrocarbons. This mode of sample ionization provided mass spectra with better signal/noise ratios and without unwanted side-products. It also extended the applicability of DAPCI to petroleum constituents which could not be analyzed through proton transfer (e.g., higher molecular PAHs such as chrysene). The thermochemistry governing the individual ionization processes is discussed and a desorption/ionization mechanism is inferred. © 2012 Elsevier B.V.

ZrC Ceramics Prepared by Self-propagating High-temperature Synthesis/Single Action Pressing

Directory of Open Access Journals (Sweden)

CHENG Yong

2017-01-01

Full Text Available ZrC ceramics were prepared by mechanical axial compression of self-propagating high-temperature synthesis/single action pressing (SHS/SAP.The effects of pressure on microstructure and densification of the products,as well as the relationship between displacement/variation of the load curve and SHS reaction,were studied.The structure and properties of the products were investigated by XRD and SEM.In addition,the density was measured by the drain away liquid method.Meanwhile,universal testing machine was used to record the displacement and load curve alternations.The results indicate that products are mainly composed of ZrC phase,the process of exhaust are accelerated as the increasing of pressure as well,leading to the smaller size of porosity and crystal particles.Density manifested as an increasing pattern by the elevated pressure with no longer change at 80MPa.Due to the strong attenuation of pressure at the peak of temperature,the density of the production is only 65.7% in 120MPa.The end point of the SHS reaction and the plastic time of the products can be monitored by displacement and load curve.The results provide evidence for the application of self-propagating high-temperature synthesis/pseudo-hot isostatic pressing to further improve the density of ceramics.

Photocatalytic activity and RNO dye degradation of nitrogen-doped TiO{sub 2} prepared by ionothermal synthesis

Energy Technology Data Exchange (ETDEWEB)

Pipi, Angelo; Ruotolo, Luis, E-mail: pluis@ufscar.br [Universidade Federal de Sao Carlos (UFSCar), SP (Brazil). Departamento de Engenharia Quimica; Byzynski, Gabriela [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Araraquara, SP (Brazil)

2017-05-15

This work concerns the preparation a nitrogen-doped TiO{sub 2} by ionothermal synthesis methods and the photocatalytic studies. In this procedure, alkoxide was used as a titanium source, and a deep eutectic mixture of choline chloride and urea (molar ratio 1:2) served as a solvent and source of nitrogen. Different samples were synthesized varying the percentages of the eutectic mixture, titanium butoxide, and water, as well as temperature and reaction time. The catalysts were characterized by X-ray diffraction, Raman spectrometry, scanning electron microscopy, and diffuse reflectance spectroscopy. N-doping was confirmed by X-ray photoelectron spectroscopy. The photocatalytic activity of the N-TiO{sub 2} nanoparticles was evaluated in the oxidation of N,N-dimethyl-4-nitrosoaniline (RNO) dye. The best photocatalytic activity under illumination by UV and visible light was found for the catalysts prepared under reflux in the presence of water, and for the catalysts prepared hydrothermally using intermediate percentages of the nitrogen source (the eutectic mixture). (author)

Some technical subjects on production of hydrocarbon fuel from synthetic gas

Energy Technology Data Exchange (ETDEWEB)

Suzuki, Takashi

1987-06-20

Since fuel oil meeting the requirements of current petroleum products can be produced by SASOL F-T synthetic process, the manufacturing process of hydrocarbon fuel oil from the coal-derived synthesis gas, downstream processes are being successively investigated. Mobile M-gasoline, MTG, process which produces gasoline from the natural gas-derived synthesis gas through methanol went into commercial operation in New Zealand in 1986. Although the gasoline suffices the quality of commercial gasoline by both fixed bed and fluidized bed systems, the price and service life of catalyst and control of by-product durene must be improved. Any STG processes have not been completed yet and the yield and quality of gasoline are inferior to those of gasoline produced by the MTG process. Applying two-stage process, the STG process will be more economically effective.(21 refs, 4 figs, 10 tabs)

Stable tetrabenzo-Chichibabin's hydrocarbons: Tunable ground state and unusual transition between their closed-shell and open-shell resonance forms

KAUST Repository

Zeng, Zebing

2012-09-05

Stable open-shell polycyclic aromatic hydrocarbons (PAHs) are of fundamental interest due to their unique electronic, optical, and magnetic properties and promising applications in materials sciences. Chichibabin\\'s hydrocarbon as a classical open-shell PAH has been investigated for a long time. However, most of the studies are complicated by their inherent high reactivity. In this work, two new stable benzannulated Chichibabin\\'s hydrocarbons 1-CS and 2-OS were prepared, and their electronic structure and geometry in the ground state were studied by various experiments (steady-state and transient absorption spectra, NMR, electron spin resonance (ESR), superconducting quantum interference device (SQUID), FT Raman, X-ray crystallographic etc.) and density function theory (DFT) calculations. 1-CS and 2-OS exhibited tunable ground states, with a closed-shell quinoidal structure for 1-CS and an open-shell biradical form for 2-OS. Their corresponding excited-state forms 1-OS and 2-CS were also chemically approached and showed different decay processes. The biradical 1-OS displayed an unusually slow decay to the ground state (1-CS) due to a large energy barrier (95 ± 2.5 kJ/mol) arising from severe steric hindrance during the transition from an orthogonal biradical form to a butterfly-like quinoidal form. The quick transition from the quinoidal 2-CS (excited state) to the orthogonal biradicaloid 2-OS (ground state) happened during the attempted synthesis of 2-CS. Compounds 1-CS and 2-OS can be oxidized into stable dications by FeCl 3 and/or concentrated H 2SO 4. The open-shell 2-OS also exhibited a large two-photon absorption (TPA) cross section (760 GM at 1200 nm). © 2012 American Chemical Society.

Catalytic synthesis of alcoholic fuels for transportation from syngas

Energy Technology Data Exchange (ETDEWEB)

Qiongxiao Wu

2012-12-15

Based on input from computational catalyst screening, an experimental investigation of promising catalyst candidates for methanol synthesis from syngas has been carried out. Cu-Ni alloys of different composition have been identified as potential candidates for methanol synthesis. These Cu-Ni alloy catalysts have been synthesized and tested in a fixed-bed continuous-flow reactor for CO hydrogenation. The metal area based activity for a Cu-Ni/SiO2 catalyst is at the same level as a Cu/ZnO/Al2O3 model catalyst. The high activity and selectivity of silica supported Cu-Ni alloy catalysts agrees with the fact that the DFT calculations identified Cu-Ni alloys as highly active and selective catalysts for the hydrogenation of CO to form methanol. This work has also provided a systematic study of Cu-Ni catalysts for methanol synthesis from syngas. The following observations have been made: (1) Cu-Ni catalysts (Cu/Ni molar ratio equal to 1) supported on SiO2, ZrO2, {gamma}-Al2O3, and carbon nanotubes exhibit very different selectivities during CO hydrogenation. However, the metal area based CO conversion rates of all supported Cu-Ni catalysts are at the same level. Carbon nanotubes and SiO2 supported Cu-Ni catalysts show high activity and selectivity for methanol synthesis. The Cu-Ni/ZrO2 catalyst exhibits high methanol selectivity at lower temperatures (250 deg. C), but the selectivity shifts to hydrocarbons and dimethyl ether at higher temperatures (> 275 deg. C). It seems likely that the Cu-Ni alloys always produce methanol, but that some supports further convert methanol to different products. (2) Cu-Ni/SiO2 catalysts have been prepared with different calcination and reduction procedures and tested in the synthesis of methanol from H2/CO. The calcination of the impregnated catalysts (with/without calcination step) and different reduction procedures with varying hydrogen concentration have significant influence on Cu-Ni alloy formation and the alloy particle size and

Assessment of polycyclic aromatic hydrocarbons (PAHs) pollution in soil of suburban areas in Tianjin, China.

Science.gov (United States)

Lv, Jungang; Shi, Rongguang; Cai, Yanming; Liu, Yong

2010-07-01

Soil contamination with polycyclic aromatic hydrocarbons is an increasing problem and has aroused more and more concern in many countries, including China. In this study, representative soil samples (n = 87) of suburban areas in Tianjin (Xiqing, Dongli, Jinnan, Beichen) were evaluated for 16 polycyclic aromatic hydrocarbons. Surface soil samples were air-dried and sieved. Microwave assisted extraction was used for polycyclic aromatic hydrocarbons preparation prior to analysis with gas chromatography-mass spectrometry. The total concentrations of tested polycyclic aromatic hydrocarbons in Xiqing, Dongli, Jinnan, Beichen ranged in 58.5-2,748.3, 36.1-6,734.7, 58.5-4,502.5, 29.7-852.5 ng/g and the averages of total concentration of polycyclic aromatic hydrocarbons were 600.5, 933.6, 640.8, 257.3 ng/g, respectively. Spatial variation of polycyclic aromatic hydrocarbons in soil was illustrated; Pollution status and comparison to other cities were also investigated. Serious polycyclic aromatic hydrocarbons soil pollution was found in Dongli district, on the contrary, Bap in most sites in Beichen did not exceed relative standards and most sites in Beichen should be classified as non-contaminated soil. Principal component analysis was used to identify the possible sources of different districts. It turned out that coal combustion still was the most important sources in three districts except Beichen. Coking, traffic, cooking, biomass combustion also accounted for polycyclic aromatic hydrocarbons pollution to certain extent in different districts. These data can be further used to assess the health risk associated with soils polluted with polycyclic aromatic hydrocarbons and help local government find proper way to reduce polycyclic aromatic hydrocarbons pollution in soils.

Photon up-conversion production in Tb{sup 3+}–Yb{sup 3+} co-doped CaF{sub 2} phosphors prepared by combustion synthesis

Energy Technology Data Exchange (ETDEWEB)

Rakov, Nikifor, E-mail: nikifor.gomez@univasf.edu.br [PG—Ciência dos Materiais, Universidade Federal do Vale do São Francisco, 48902-300 Juazeiro, BA (Brazil); Guimarães, Renato B. [Instituto de Física, Universidade Federal Fluminense, 24210-346 Niterói, RJ (Brazil); Maciel, Glauco S., E-mail: glauco@if.uff.br [Instituto de Física, Universidade Federal Fluminense, 24210-346 Niterói, RJ (Brazil)

2016-02-15

Graphical abstract: Up-conversion luminescence from Tb{sup 3+} obtained by energy transfer from Yb{sup 3+} pairs in CaF{sub 2} powder prepared by combustion synthesis. - Highlights: • Calcium fluoride (CaF{sub 2}) powders were prepared by combustion synthesis. • Rare-earth ions doped in this material were found in interstitial sites. • Cooperative up-conversion was observed in Tb{sup 3+}:Yb{sup 3+}:CaF{sub 2} powder. • Energy transfer between Tb{sup 3+} and pairs of Yb{sup 3+} was analyzed using rate equations. - Abstract: Calcium fluoride (CaF{sub 2}) crystalline powders were successfully prepared by the combustion synthesis method. The powder material containing luminescent rare-earth ions, more specifically terbium (Tb{sup 3+}) and ytterbium (Yb{sup 3+}), was studied by X-ray diffraction, scanning electronic microscopy and optical spectroscopy. These ions are allocated in charge compensated interstitial positions of tetragonal (C{sub 4v}) and trigonal (C{sub 3v}) symmetry sites of the cubic (O{sub h}) CaF{sub 2} lattice. Up-conversion (UC) luminescence in Tb{sup 3+} was achieved using a low power diode laser operating at 975 nm. Tb{sup 3+} is insensitive to near-infrared radiation but UC can be achieved via energy transfer from pairs of Yb{sup 3+} ions to Tb{sup 3+} ions. The UC luminescence dynamics of Tb{sup 3+} was used to study the energy transfer mechanism.

Preparing interesting hydrocarbons by hydrogenation, etc

Energy Technology Data Exchange (ETDEWEB)

1938-02-15

Now, it has been found that gasoline and a combustible oil are produced by destructive hydrogenation of pastes prepared from solid carbonaceous materials and mixtures of middle oils and the mud in question, by regulating the composition of the products removed as vapors in a way that they contain at least the total new heavy oil formed in the course of the destructive hydrogenation and in using as mixing agent for the new raw material the mud proceeding from the operation and middle oil, having withdrawn from this mud all or part of the solid constituents. This destructive hydrogenation is carried out in a converter where a constant level of liquid is maintained, the vapors escaping at the top of the converter and the mud being drawn off at one or more places from the column of liquid undergoing reaction.

Features of fatty acid synthesis in higher plants

Energy Technology Data Exchange (ETDEWEB)

Yamada, M [Tokyo Univ. (Japan). Coll. of General Education; Nakamura, Y

1975-07-01

In the biosynthesis of fatty acid in the presence of /sup 3/H/sub 2/O, /sup 3/H is incorporated into the hydrocarbon chain of the fatty acid. The features in the fatty acid synthesis of higher plants were investigated by applying /sup 3/H/sub 2/O method to the measurement of the ability of spinach leaves synthesizing fatty acid. Sucrose, acetate, pyruvate, PGA, PEP, OAA, citrate, etc. were employed as the substrates of fatty acid synthesis to trace the process of synthesis of each fatty acid. The demand of various cofactors related to the ability of spinach chloroplast fatty acid synthesizing was also examined. Light dependence of the fatty acid synthesis of chloroplast as well as the influences of N,N'-dicyclohexyl carbodiimide, carbonylcyanide-4-trifluoromethoxy phenyl hydrazone and NH/sub 4/Cl were discussed. The results were compared with the reports on the fatty acid synthesis of avocado pear, castor bean, etc.

Comparative Genomics of the Ubiquitous, Hydrocarbon-degrading Genus Marinobacter

Science.gov (United States)

Singer, E.; Webb, E.; Edwards, K. J.

2012-12-01

using fimbriae and pili. Formation of biofilm with biosurfactant characteristics has been observed in Marinobacter cultures and environmental strains in relation to hydrocarbon degradation. Genomic potential exists for the synthesis of biofilm-related carbon and energy storage compounds, e.g. alginate and isoprenoid wax esters, and quorum sensing encoded by the regulatory luxR gene and N-acyl-L-homoserine lactone (AHL) signals. Halotolerance is predicted to be achieved through biosynthesis and/or import of compatible solutes, including glycine betaine, choline, ectoine, sucrose, periplasmic glucans as well as membrane channel activity regulating intracellular sodium, potassium and chloride concentration balance. Gene abundances concur with those observed in sequenced halophilic Halomonas genomes. Defense mechanisms are plentiful and include arsenate, organic solvent, copper, and mercuric resistance, compounds, which frequently occur in oil refinery wastewater. The Marinobacter genomes reflect dynamic environments and diverse interactions with viruses and other bacteria with similar metabolic strategies, as reflected by the large number of integrases and transposases. This study has provided comprehensive genomic insights into the metabolic versatility and predicted environmental impact potential of one of the most ubiquitous bacterial genera.

Performance of a Throttle Cycle Refrigerator with Nitrogen-Hydrocarbon and Argon-Hydrocarbon Mixtures

Science.gov (United States)

Venkatarathnam, G.; Senthil Kumar, P.; Srinivasa Murthy, S.

2004-06-01

Throttle cycle refrigerators are a class of vapor compression refrigerators that can provide refrigeration at cryogenic temperatures and operate with refrigerant mixtures. The performance of our prototype refrigerators with nitrogen-hydrocarbon, nitrogen-hydrocarbon-helium and argon-hydrocarbon refrigerant mixtures is presented in this paper.

Petroleum hydrocarbons and polycyclic aromatic hydrocarbons (PAHs) in Hong Kong marine sediments

International Nuclear Information System (INIS)

Zheng, G.J.; Richardson, B.J.

1999-01-01

A total of 20 surficial sediment samples, obtained from Hong Kong coastal waters, were analysed for petroleum hydrocarbons (PHCs) and a suite of 15 polycyclic aromatic hydrocarbons (PAHs). The results indicate that Hong Kong coastal sediments are often seriously polluted with petroleum related hydrocarbons. This is especially so in heavily urbanised or industrialized localities, such as Kowloon Bay (Victoria Harbour), Tsing Yi North and Tolo Harbour. Petroleum hydrocarbon pollutants in marine sediments are believed to be mainly derived from the transportation of oil, shipping activities, spillages, and industrial, stormwater and waste wastewater discharge. The ratio of unresolved complex mixture (UCM) to n-alkanes, carbon preference index (CPI), and n-C 16 values indicate that the main contribution to petroleum hydrocarbon contamination is via oil and its products. Pollutant sources appear to be stable and continuing when compared with previous data. (author)

Purifying hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Demoulins, H D; Garner, F H

1923-02-07

Hydrocarbon distillates, including natural gases and vapors produced by cracking hydrocarbon oils, are desulfurized etc. by treating the vapor with an aqueous alkaline solution of an oxidizing agent. The hydrocarbons may be previously purified by sulfuric acid. In examples aqueous solutions of sodium or calcium hydrochlorite containing 1.5 to 5.0 grams per liter of available chlorine and sufficient alkali to give an excess of 0.1 percent in the spent reagent are preheated to the temperature of the vapor, and either sprayed or atomized into the vapors near the outlet of the dephlegmator or fractionating tower, or passed in countercurrent to the vapors through one or a series of scrubbers.

Synthesis of Fire-Extinguishing Dawsonites

Science.gov (United States)

Altman, R. L.

1982-01-01

Simple nonaqueous process synthesizes sodium or potassium, dawsonites effective against hydrocarbon fuel fires. Fire-extinguishing alkali metal dawsonites are prepared using a finely-pulverized equimolar mixture of hydrogen carbonate, or carbonates and aluminum hydroxide heated for 1 to 6 hours under carbon dioxide pressure.

Ambient aromatic hydrocarbon measurements at Welgegund, South Africa

Science.gov (United States)

Jaars, K.; Beukes, J. P.; van Zyl, P. G.; Venter, A. D.; Josipovic, M.; Pienaar, J. J.; Vakkari, V.; Aaltonen, H.; Laakso, H.; Kulmala, M.; Tiitta, P.; Guenther, A.; Hellén, H.; Laakso, L.; Hakola, H.

2014-07-01

Aromatic hydrocarbons are associated with direct adverse human health effects and can have negative impacts on ecosystems due to their toxicity, as well as indirect negative effects through the formation of tropospheric ozone and secondary organic aerosol, which affect human health, crop production and regional climate. Measurements of aromatic hydrocarbons were conducted at the Welgegund measurement station (South Africa), which is considered to be a regionally representative background site. However, the site is occasionally impacted by plumes from major anthropogenic source regions in the interior of South Africa, which include the western Bushveld Igneous Complex (e.g. platinum, base metal and ferrochrome smelters), the eastern Bushveld Igneous Complex (platinum and ferrochrome smelters), the Johannesburg-Pretoria metropolitan conurbation (> 10 million people), the Vaal Triangle (e.g. petrochemical and pyrometallurgical industries), the Mpumalanga Highveld (e.g. coal-fired power plants and petrochemical industry) and also a region of anticyclonic recirculation of air mass over the interior of South Africa. The aromatic hydrocarbon measurements were conducted with an automated sampler on Tenax-TA and Carbopack-B adsorbent tubes with heated inlet for 1 year. Samples were collected twice a week for 2 h during daytime and 2 h during night-time. A thermal desorption unit, connected to a gas chromatograph and a mass selective detector was used for sample preparation and analysis. Results indicated that the monthly median (mean) total aromatic hydrocarbon concentrations ranged between 0.01 (0.011) and 3.1 (3.2) ppb. Benzene levels did not exceed the local air quality standard limit, i.e. annual mean of 1.6 ppb. Toluene was the most abundant compound, with an annual median (mean) concentration of 0.63 (0.89) ppb. No statistically significant differences in the concentrations measured during daytime and night-time were found, and no distinct seasonal patterns were

Synthesis of calcium phosphates and porous hydroxyapatite beads prepared by emulsion method

Energy Technology Data Exchange (ETDEWEB)

Chen, B.-H. [Faculty of Biotechnology, Kaohsiung Medical University, 100 Shih-Chuan 1st Road, Kaohsiung 807, Taiwan (China); Chen, K.-I [Department of Electronics Engineering and Computer Science, Tung-Fang Institute of Technology, 100 Dungfang Road, Hunei, Kaohsiung, Taiwan (China); Ho, M.-L. [Department of Physiology, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China); Chen, H.-N. [Faculty of Medicinal and Applied Chemistry, Kaohsiung Medical University, 100 Shih-Chuan 1st Road, Kaohsiung 807, Taiwan (China); Chen, W.-C. [Faculty of Dentistry, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China); Wang, C.-K. [Faculty of Medicinal and Applied Chemistry, Kaohsiung Medical University, 100 Shih-Chuan 1st Road, Kaohsiung 807, Taiwan (China)], E-mail: ckwang@kmu.edu.tw

2009-01-15

Raw calcium phosphates were synthesized via a chemical reaction between 0.5 M orthophosphoric acid and 0.5 M calcium hydroxide. Hydroxyapatite (HAp), {beta}-tricalcium phosphate ({beta}-TCP) or biphase calcium phosphate (BCP) comprising HAp and {beta}-TCP were obtained by changing pH value, Ca/P ratio, and the addition of glycerol. The as-synthesized and heat-treated powders were analyzed by X-ray diffraction (XRD) and Fourier transformation infrared spectrometry (FTIR). Thermal stability of the pure apatite phase was obtained to be 1300 deg. C, while synthesis was done at the pH value of 10.0 with a Ca/P ratio of 2.0 and a temperature of 37 deg. C. Besides, the {beta}-TCP phase (with higher purity) was achieved at 800 deg. C, whose synthesis was done at pH 6.4 with a Ca/P ratio of 1.5 and a temperature of 37 deg. C. Therefore, the biphase bioceramics comprising of HAp and {beta}-TCP could be obtained, since it was manipulated suitably. The HAp raw material was subjected to a simple emulsion method for the preparation of porous beads. They should have the advantage of exhibiting higher adsorptive ability and osteoconductivity in comparison with the sintered dense apatite. Additionally, the porous beads of apatite were demonstrated to be non-toxic to cells, and should be suitable for the use as a scaffold of cultured bone and bone graft material, as well as for drug delivery systems.

Ambient aromatic hydrocarbon measurements at Welgegund, South Africa

Energy Technology Data Exchange (ETDEWEB)

Jaars, K.; Beukes, J. P.; van Zyl, P. G.; Venter, A. D.; Josipovic, M.; Pienaar, J. J.; Vakkari, Ville; Aaltonen, H.; Laakso, H.; Kulmala, M.; Tiitta, P.; Guenther, Alex B.; Hellen, H.; Laakso, L.; Hakola, H.

2014-07-11

Aromatic hydrocarbons are associated with direct adverse human health effects and can have negative impacts on ecosystems due to their toxicity, as well as indirect negative effects through the formation of tropospheric ozone and secondary organic aerosol that affect human health, crop production and regional climate. Measurements were conducted at the Welgegund measurement station (South Africa) that is considered to be a regionally representative background site. However, the site is occasionally impacted by plumes from major anthropogenic source regions in the interior of South Africa, which include the western Bushveld Igneous Complex (e.g. platinum, base metal and ferrochrome smelters), the eastern Bushveld Igneous Complex (platinum and ferrochrome smelters), the Johannesburg-Pretoria metropolitan conurbation (>10 million people), the Vaal Triangle (e.g. petrochemical and industries), the Mpumalanga Highveld (e.g. coal-fired power plants and petrochemical industry) and also a region of anti-cyclonic recirculation of air mass over the interior of South Africa. The aromatic hydrocarbon measurements were conducted with an automated sampler on Tenax-TA and Carbopack-B adsorbent tubes with heated inlet for one year. Samples were collected twice a week for two hours during daytime and two hours 1 during night-time. A thermal desorption unit, connected to a gas chromatograph and a mass 2 selective detector was used for sample preparation and analysis. Results indicated that the 3 monthly median total aromatic hydrocarbon concentrations ranged between 0.01 to 3.1 ppb. 4 Benzene levels did not exceed local air quality standards. Toluene was the most abundant 5 species, with an annual median concentration of 0.63 ppb. No statistically significant 6 differences in the concentrations measured during daytime and night-time were found and no distinct seasonal patterns were observed. Air mass back trajectory analysis proved that the lack of seasonal cycles could be

A crude protective film on historic stones and its artificial preparation through biomimetic synthesis

Science.gov (United States)

Liu, Qiang; Zhang, Bingjian; Shen, Zhongyue; Lu, Huanming

2006-12-01

A biomimetic film has been found on the surface of the historic stone buildings and monuments. The stone inscriptions under the film are preserved so well that has not been damaged for more than 1000 years. Samples of the crude film have been analyzed by XRD, FTIR, PLM, EDA, SEM and TEM. The results show that it consists mainly of calcium oxalate monohydrate. On the basis of the existence of the organism debris, it is concluded that the film should be a product of biomineralization. According to this hypothesis, a similar film has been prepared on the stone surface through biomimetic synthesis in our laboratory. The preliminary analysis shows that the artificial protective film functions well.

TiO2 on magnesium silicate monolith: effects of different preparation techniques on the photocatalytic oxidation of chlorinated hydrocarbons

International Nuclear Information System (INIS)

Cardona, Ana I.; Candal, Roberto; Sanchez, Benigno; Avila, Pedro; Rebollar, Moises

2004-01-01

In this article, the comparative results of the photocatalytic oxidation of trichloroethylene (TCE) alone and a mixture of chlorinated hydrocarbons (trichloroethylene, perchloroethylene and chloroform) in gas phase, obtained with three different monolithic catalysts in a flat reactor frontally illuminated with a Xenon lamp are presented. The three catalysts incorporate titanium dioxide (TiO 2 ) as active phase on a magnesium silicate support, by means of different procedures: (i) incorporation of commercial TiO 2 powder into the silicate matrix ('massic monolith'); (ii) sol-gel coating of the silicate support; (iii) impregnation with a commercial TiO 2 aqueous suspension of the same silicate support. In the first case, the massic monolith was made from a 50:50 w/w mixture of magnesium silicate and 'Titafrance G5' TiO 2 powder. In the second case, a magnesium silicate monolith was coated with several layers of an aqueous TiO 2 sol prepared from hydrolysis and condensation of titanium tetra-isopropoxide (Ti(OC 3 H 7 ) 4 ) in excess of acidified water (acid catalysis). The third catalyst was prepared by impregnating the same silicate support with several layers of 'Titafrance G5' TiO 2 powder water suspension. All the catalysts were thermal treated under comparable conditions in order to fix the TiO 2 active phase to the silicate support. Although the performance of the massic monolith was better than the sol-gel monolith, the latter is of great interest because this technique allows the chemical composition of the active films to be easily modified

Method of preparing and utilizing a catalyst system for an oxidation process on a gaseous hydrocarbon stream

Science.gov (United States)

Berry, David A; Shekhawat, Dushyant; Smith, Mark; Haynes, Daniel

2013-07-16

The disclosure relates to a method of utilizing a catalyst system for an oxidation process on a gaseous hydrocarbon stream with a mitigation of carbon accumulation. The system is comprised of a catalytically active phase deposited onto an oxygen conducting phase, with or without supplemental support. The catalytically active phase has a specified crystal structure where at least one catalytically active metal is a cation within the crystal structure and coordinated with oxygen atoms within the crystal structure. The catalyst system employs an optimum coverage ratio for a given set of oxidation conditions, based on a specified hydrocarbon conversion and a carbon deposition limit. Specific embodiments of the catalyst system are disclosed.

Carbon-14 studies on the role of oxygen-containing compounds in the reaction mechanism of the Fischer-Tropsch synthesis

International Nuclear Information System (INIS)

Aksoy, H.A.

1975-01-01

In this work the behaviour of organic oxygen compounds has been studied in the reaction mechanism of Fischer-Tropsch synthesis using the tracer method. As an oxygen carrying tracer materials i-propanole (2- 14 C), acetone (2- 14 C) and ethanole (1- 14 C) have been added to the synthesis gas. The synthesis experiments are performed under standard conditions: The synthesis products are separated in suitable fractions and then studied by gas- and radio-gaschromatography. As a result the C-number distributions of the synthesis products are obtained as a function of concentration (weight %, mol %) and radioactivity (activity %). On this basis the relative molar activities have been calculated for certain compounds and fractions. Adding i-propanole- 14 C a great part of the tracer compound is transformed to acetone- 14 C, however adding acetone- 14 C to the synthesis gas a large amount of i-propanole- 14 C is produced. The main hydrocarbon reaction product from i-propanol and acetone is propane. Besides propane also propene is produced with equal molar radioactivity. This indicates that the formation of adsorbed oxygen compounds, as they may also be produced by chemisorption from alcohols or carbonyle compounds, is the first step in the formation of hydrocarbons by hydrogenolytic separation of oxygen. Comparing the results obtained with ethanole- 14 C and i-propanole- 14 C as a tacer material, for ethane an essentially lower molar activity is obtained when adding ethanole- 14 C compared with propane when adding i-propanole- 14 C. This corresponds with a particularly low desorption probability at the C 2 -hydrocarbon level. (orig./HK) [de

The direct conversion of synthesis gas to chemicals / Ernest du Toit

OpenAIRE

Du Toit, Ernest

2002-01-01

The catalytic conversion of synthesis gas, obtainable from the processing of coal, biomass or natural gas, to a complex hydrocarbon product stream can be achieved via the Fischer-Tropsch process. The Fischer-Tropsch synthesis process has evolved from being mainly a fuel producing process in the early 1950's to that of a solvent and speciality wax production process towards the end of the 1970's. From the early 1980's there has been a clear shift towards the production of commod...

Methodological aspects of fuel performance system analysis at raw hydrocarbon processing plants

Science.gov (United States)

Kulbjakina, A. V.; Dolotovskij, I. V.

2018-01-01

The article discusses the methodological aspects of fuel performance system analysis at raw hydrocarbon (RH) processing plants. Modern RH processing facilities are the major consumers of energy resources (ER) for their own needs. To reduce ER, including fuel consumption, and to develop rational fuel system structure are complex and relevant scientific tasks that can only be done using system analysis and complex system synthesis. In accordance with the principles of system analysis, the hierarchical structure of the fuel system, the block scheme for the synthesis of the most efficient alternative of the fuel system using mathematical models and the set of performance criteria have been developed on the main stages of the study. The results from the introduction of specific engineering solutions to develop their own energy supply sources for RH processing facilities have been provided.

Preparation and characterization of stable copper/zinc oxide/alumina catalysts for methanol synthesis

Energy Technology Data Exchange (ETDEWEB)

Hoeppener, R H; Doesburg, E B; Scholten, J J

1986-08-15

A series of Cu/ZnO/Al/sub 2/O/sub 3/ catalysts for the low pressure methanol synthesis has been prepared by coprecipitation with a sodium carbonate solution from solutions of a mixture of the corresponding metal nitrates, followed by drying, calcination and reduction. The catalysts and their precursors were analyzed by techniques like X-ray diffraction, X-ray line broadening, differential thermal analysis, chemical analysis, adsorptive decomposition of N/sub 2/O and B.E.T.-measurements. The catalytic activity for the methanol synthesis was determined in a flow reactor under industrial conditions. Depending on the metal ion ratio in the initial metal nitrate solutions different compounds were formed during coprecipitation, like rosasite, malachite, Cu, Zn-hydrotalcite and a ternary compound which was called roderite. Its structure is unknown and it contains, besides Zn/sup 2+/, up to 28 at% Cu/sup 2+/ and up to 17 at% Al/sup 3+/. Addition of 7 at% Mg/sup 2+/ stabilizes the Cu, Zn-hydrotalcite structure but leads to a drastic decrease in catalytic activity. The rate of methanol production depends on the phase composition of the precursors. Rosasite containing precursors give the highest activity; hydrotalcite proves to be an excellent catalyst stabilizer which evokes the formation of small Cu and ZnO particles. Mg/sup 2+/ inhibits methanol production. 6 figs., 1 tab., 18 refs.

The complex synthesis and solid state chemistry of ceria-lanthana solid solutions prepared via a hexamethylenetetramine precipitation

International Nuclear Information System (INIS)

Fleming, P.G.; Holmes, J.D.; Otway, D.J.; Morris, M.A.

2011-01-01

Mixed oxide solid solutions are becoming ever more commercially important across a range of applications. However, their synthesis can be problematical. Here, we show that ceria-lanthana solid solutions can be readily prepared via simple precipitation using hexamethylenetetramine. However, the solution chemistry can be complex, which results in the precipitated particles having a complex structure and morphology. Great care must be taken in both the synthesis and characterisation to quantify the complexity of the product. Even very high heat treatments were not able to produce highly homogeneous materials and X-ray diffractions reveals the non-equilibrium form of particles prepared in this way. Unexpected crystal structures are revealed including a new metastable cubic La 2 O 3 phase. - Graphical abstract: The suggested mechanism for the formation of dual fluorite phase particles, where Step 1 corresponds to room temperature aging, Step 2; heating the solution to 90 deg. C, Step 3; cooling of the solution to room temperature, Step 4; calcination to 500 deg. C, Step 5; calcination to 700 deg. C and Step 6; calcination to 1300 deg. C. The terminology of e.g. La 1-x Ce x (OH) 3 is used to indicate the formation of a mixed oxy-hydroxy participate rather than a definitive assignment of stoichiometry. Similarly, La 1-y Ce y O 2 only implies a mixed solid solution. Highlights: → Mol% of prepared Ce-La oxides did not follow that of reactant mol%. → Complex reaction pathway found to be dependent on metal solution concentrations. → At certain concentrations core shell particles were found to form. → A reaction model was produced based on cationic solubility. → Report lanthana solubility higher than previously reported in CeO 2 .

The role of polyhalogenated aromatic hydrocarbons on thyroid hormone disruption and cognitive function: a review.

Science.gov (United States)

Builee, T L; Hatherill, J R

2004-11-01

Thyroid hormones (TH) are essential to normal brain development, influencing behavior and cognitive function in both adult and children. It is suggested that conditions found in TH abnormalities such as hypothyroidism, hyperthyroidism and generalized resistance to thyroid hormone (GRTH) share symptomatic behavioral impulses found in cases of attention deficit hyperactivity disorder (ADHD) and other cognitive disorders. Disrupters of TH are various and prevalent in the environment. This paper reviews the mechanisms of TH disruption caused by the general class of polyhalogenated aromatic hydrocarbons (PHAH)'s acting as thyroid disrupters (TD). PHAHs influence the hypothalamus-pituitary-thyroid (HPT) axis, as mimicry agents affecting synthesis and secretion of TH. Exposure to PHAH induces liver microsomal enzymes UDP-glucuronosyltransferase (UGT) resulting in accelerated clearance of TH. PHAHs can compromise function of transport and receptor binding proteins such as transthyretin and aryl hydrocarbon receptors (Ahr). Glucose metabolism and catecholamine synthesis are disrupted in the brain by the presence of PHAH. Further, PHAH can alter brain growth and development by perturbing cytoskeletal formation, thereby affecting neuronal migration, elongation and branching. The complex relationships between PHAH and cognitive function are examined in regard to the disruption of T4 regulation in the hypothalamus-pituitary-thyroid axis, blood, brain, neurons, liver and pre and postnatal development.

Fischer-Tropsch synthesis. Development and perspectives

Energy Technology Data Exchange (ETDEWEB)

Schaub, G.; Rohde, M.; Mena Subiranas, A. [Karlsruhe Univ. (Germany). Engler-Bunte-Institut

2006-07-01

Production of synthetic hydrocarbons via Fischer-Tropsch (FT) synthesis has the potential to produce high-value automotive fuels and petrochemicals from fossil and renewable sources. The availability of cheap natural gas and solid raw materials like coal and biomass has given momentum to synthesis technologies first developed in the mid-twentieth century. The present paper summarizes the fundamentals and describes some general aspects regarding driving forces, catalyst and reaction, synthesis reactor, and overall process. In this way, it indicates the context of present and future developments. Worldwide plant capacities will increase significantly in the next future, with natural gas favored as feedstock. Substitution of petroleum as well as production of improved products (like automotive fuels) are the most significant incentives. Energy loss and additional fossil CO{sub 2} emissions caused by the conversion process will be a problem in extended applications with fossil feedstocks. The current R and D activities worldwide, in all areas related to Fischer-Tropsch synthesis, will contribute to further process improvements and extended applications. (orig.)

Plasma devices for hydrocarbon reformation

KAUST Repository

Cha, Min

2017-01-01

Plasma devices for hydrocarbon reformation are provided. Methods of using the devices for hydrocarbon reformation are also provided. The devices can include a liquid container to receive a hydrocarbon source, and a plasma torch configured

The role of zeolite in the Fischer–Tropsch synthesis over cobalt–zeolite catalysts

International Nuclear Information System (INIS)

Sineva, L V; Mordkovich, V Z; Asalieva, E Yu

2015-01-01

The review deals with the specifics of the Fischer–Tropsch synthesis for the one-stage syncrude production from CO and H 2 in the presence of cobalt–zeolite catalytic systems. Different types of bifunctional catalysts (hybrid, composite) combining a Fischer–Tropsch catalyst and zeolite are reviewed. Special attention focuses on the mechanisms of transformations of hydrocarbons produced in the Fischer–Tropsch process on zeolite acid sites under the synthesis conditions. The bibliography includes 142 references

ZnO-nanorod-array/p-GaN high-performance ultra-violet light emitting devices prepared by simple solution synthesis

Science.gov (United States)

Jha, Shrawan Kumar; Luan, Chunyan; To, Chap Hang; Kutsay, Oleksandr; Kováč, Jaroslav; Zapien, Juan Antonio; Bello, Igor; Lee, Shuit-Tong

2012-11-01

Pure ultra-violet (UV) (378 nm) electroluminescence (EL) from zinc oxide (ZnO)-nanorod-array/p-gallium nitride (GaN) light emitting devices (LEDs) is demonstrated at low bias-voltages (˜4.3 V). Devices were prepared merely by solution-synthesis, without any involvement of sophisticated material growth techniques or preparation methods. Three different luminescence characterization techniques, i.e., photo-luminescence, cathodo-luminescence, and EL, provided insight into the nature of the UV emission mechanism in solution-synthesized LEDs. Bias dependent EL behaviour revealed blue-shift of EL peaks and increased peak sharpness, with increasing the operating voltage. Accelerated bias stress tests showed very stable and repeatable electrical and EL performance of the solution-synthesized nanorod LEDs.

Synthesis and characterization of triangulene

Science.gov (United States)

Pavliček, Niko; Mistry, Anish; Majzik, Zsolt; Moll, Nikolaj; Meyer, Gerhard; Fox, David J.; Gross, Leo

2017-05-01

Triangulene, the smallest triplet-ground-state polybenzenoid (also known as Clar's hydrocarbon), has been an enigmatic molecule ever since its existence was first hypothesized. Despite containing an even number of carbons (22, in six fused benzene rings), it is not possible to draw Kekulé-style resonant structures for the whole molecule: any attempt results in two unpaired valence electrons. Synthesis and characterization of unsubstituted triangulene has not been achieved because of its extreme reactivity, although the addition of substituents has allowed the stabilization and synthesis of the triangulene core and verification of the triplet ground state via electron paramagnetic resonance measurements. Here we show the on-surface generation of unsubstituted triangulene that consists of six fused benzene rings. The tip of a combined scanning tunnelling and atomic force microscope (STM/AFM) was used to dehydrogenate precursor molecules. STM measurements in combination with density functional theory (DFT) calculations confirmed that triangulene keeps its free-molecule properties on the surface, whereas AFM measurements resolved its planar, threefold symmetric molecular structure. The unique topology of such non-Kekulé hydrocarbons results in open-shell π-conjugated graphene fragments that give rise to high-spin ground states, potentially useful in organic spintronic devices. Our generation method renders manifold experiments possible to investigate triangulene and related open-shell fragments at the single-molecule level.

Enantioselective synthesis of α-oxy amides via Umpolung amide synthesis.

Science.gov (United States)

Leighty, Matthew W; Shen, Bo; Johnston, Jeffrey N

2012-09-19

α-Oxy amides are prepared through enantioselective synthesis using a sequence beginning with a Henry addition of bromonitromethane to aldehydes and finishing with Umpolung Amide Synthesis (UmAS). Key to high enantioselection is the finding that ortho-iodo benzoic acid salts of the chiral copper(II) bis(oxazoline) catalyst deliver both diastereomers of the Henry adduct with high enantiomeric excess, homochiral at the oxygen-bearing carbon. Overall, this approach to α-oxy amides provides an innovative complement to alternatives that focus almost entirely on the enantioselective synthesis of α-oxy carboxylic acids.

Benthic Bioprocessing of Hydrocarbons in the Natural Deep-Sea Environment

Science.gov (United States)

Sultan, N.; MacDonald, I. R.; Bohrmann, G.; Schubotz, F.; Johansen, C.

2017-12-01

Science is accustomed to quantifying ecosystem processes that consume carbon from primary production as it drifts downward through the photic zone. Comparably efficient processes operate in reverse, as living and non-living components sequester and re-mineralize a large fraction of hydrocarbons that migrate out of traps and reservoirs to the seafloor interface. Together, they comprise a sink that prevents these hydrocarbons from escaping upward into the water column. Although quantification of the local or regional magnitude of this sink poses steep challenges, we can make progress by classifying and mapping the biological communities and geological intrusions that are generated from hydrocarbons in the deep sea. Gulf of Mexico examples discussed in this presentation extend across a broad range of depths (550, 1200, and 3200 m) and include major differences in hydrocarbon composition (from gas to liquid oil to asphaltene-dominated solids). Formation of gas hydrate is a dynamic process in each depth zone. At upper depths, gas hydrate is unstable at a timescale of months to years and serves as a substrate for microbial consortia and mussel symbiosis. At extreme depths, gas hydrate supports large and dense tubeworm colonies that conserve the material from decomposition. Timescales for biogeochemical weathering of oil and asphalts are decadal or longer, as shown by sequential alterations and changing biological colonization. Understanding these processes is crucial as we prepare for wider and deeper energy exploitation in the Gulf of Mexico and beyond.

Substrate-free microwave synthesis of graphene: experimental conditions and hydrocarbon precursors

Energy Technology Data Exchange (ETDEWEB)

Dato, Albert [Applied Science and Technology Graduate Group, University of California, Berkeley, CA 94720 (United States); Frenklach, Michael, E-mail: amdato@me.berkeley.edu, E-mail: myf@me.berkeley.edu [Department of Mechanical Engineering, University of California, Berkeley, CA 94720-1740 (United States)

2010-12-15

The effects of applied microwave power, gas flow rate and precursor composition on the substrate-free gas-phase synthesis of graphene were investigated. Graphene was produced through the delivery of ethanol droplets into argon plasmas, and a decrease in the flow rate of the gas used to generate the plasmas resulted in the formation of graphitic particles and bulk graphite structures. Carbonaceous soot particles were created by delivering isopropyl alcohol into the reactor, while no solid matter was created from methanol. Increasing the applied microwave power was found to have no effect on the structures of the synthesized materials. These findings indicated that the synthesis of graphene in the gas phase was the result of the slow inception and extremely fast growth of aromatic nuclei in the plasma afterglows.

Synthesis and structural characterization of nano-hydroxyapatite biomaterials prepared by microwave processing

Science.gov (United States)

Ramli, Rosmamuhamadani; Arawi, Ainaa Zafirah Omar; Talari, Mahesh Kumar; Mahat, Mohd Muzamir; Jais, Umi Sarah

2012-07-01

Synthetic hydroxyapatite, (HA, Ca10(PO4)6(OH)2), is an attractive and widely utilized bio-ceramic material for orthopedic and dental implants because of its close resemblance of native tooth and bone crystal structure. Synthetic HA exhibits excellent osteoconductive properties. Osteoconductivity means the ability to provide the appropriate scaffold or template for bone formation. Calcium phosphate biomaterials [(HA), tri-calcium phosphate (TCP) and biphasic calcium phosphate (HA/TCP)] with appropriate three-dimensional geometry are able to bind and concentrate endogenous bone morphogenetic proteins in circulation, and may become osteoinductive and can be effective carriers of bone cell seeds. This HA can be used in bio-implants as well as drug delivery application due to the unique properties of HA. Biomaterials synthesized from the natural species like mussel shells have additional benefits such as high purity, less expensive and high bio compatibility. In this project, HA-nanoparticles of different crystallite size were prepared by microwave synthesis of precursors. High purity CaO was extracted from the natural mussel shells for the synthesis of nano HA. Dried nano HA powders were analyzed using X-Ray Diffraction (XRD) technique for the determination of crystal structure and impurity content. Scanning Electron Microscopic (SEM) investigation was employed for the morphological investigation of nano HA powders. From the results obtained, it was concluded that by altering the irradiation time, nano HA powders of different crystallite sizes and morphologies could be produced. Crystallite sizes calculated from the XRD patterns are found to be in the range of 10-55 nm depending on the irradiation time.

Hydrocarbons and air pollution

International Nuclear Information System (INIS)

Herz, O.

1992-01-01

This paper shows the influence of hydrocarbons vapors, emitted by transports or by volatile solvents using, on air pollution. Hydrocarbons are the principal precursors of photochemical pollution. After a brief introduction on atmospheric chemistry and photochemical reactions, the author describes the french prevention program against hydrocarbons emissions. In the last chapter, informations on international or european community programs for photochemical pollution study are given. 5 figs., 10 tabs

Synthesis of metal-adeninate frameworks with high separation capacity on C{sub 2}/C{sub 1} hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

He, Yan-Ping, E-mail: hyp041@163.com [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China); Zhou, Nan [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China); Hunan GuangYi Experimental Middle School, Changsha, Hunan 410014 (China); Tan, Yan-Xi; Wang, Fei; Zhang, Jian [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China)

2016-06-15

By introducing isophthalic acid or 2,5-thiophenedicarboxylic acid to assemble with adenine and cadmium salt, two isostructural and anionic porous metal-organic frameworks (1 and 2) possessing the novel (4,8)-connected sqc topology are presented here. 1 shows permanent porosity with Langmuir surface area of 770.1 m{sup 2}/g and exhibits high separation capacity on C{sub 2}/C{sub 1} hydrocarbons. - Graphical abstract: The assembly between isophthalic acid, adenine ligands and Cd{sup 2+} ions leads to an anionic porous metal-organic frameworks, which shows permanent porosity and exhibits high C{sub 2}/C{sub 1} hydrocarbons separation capacity. Display Omitted.

Synthesis, microstructure and mechanical properties of ceria stabilized tetragonal zirconia prepared by spray drying technique

International Nuclear Information System (INIS)

Sharma, S.C.; Gokhale, N.M.; Dayal, Rajiv; Lazl, Ramji

2002-01-01

Ceria stabilized zirconia powders with ceria concentration varying from 6 to 16 mol% were synthesized using spray drying technique. Powders were characterized for their particle size distribution and specific surface area. The dense sintered ceramics fabricated using these powders were characterized for their microstructure, crystallite size and phase composition. The flexural strength, fracture toughness and micro-hardness of sintered ceramics were measured. High fracture toughness and flexural strength were obtained for sintered bodies with 12 mol% of CeO 2 . Flexural strength and fracture toughness were dependent on CeO 2 concentration, crystallite size and phase composition of sintered bodies. Correlation of data has indicated that the transformable tetragonal phase is the key factor in controlling the fracture toughness and strength of ceramics. It has been demonstrated that the synthesis method is effective to prepare nanocrystalline tetragonal ceria stabilized zirconia powders with improved mechanical properties. Ce-ZrO 2 with 20 wt% alumina was also prepared with flexural strength, 1200 MPa and fracture toughness 9.2 MPa√m. (author)

Process for the preparation of unsatured hydrocarbons. Verfahren zur Herstellung ungesaettigter Kohlenwasserstoffe

Energy Technology Data Exchange (ETDEWEB)

Tmenov, D N; Svintsov, N I; Schapovalova, L P; Tabakov, A V; Dvoretsky, M L; Vasiliev, G I; Schestovsky, G P; Kandalova, V D; Korotkevitsch, B S; Lukaschov, A I

1980-07-31

Parrafins, olefines or alkyl aromatic compounds can be dehydrated using a catalyst with a molybdenum oxide compound as the active component and magnesium oxide and crystalline clay or titanium oxide or aluminium oxide as carrier. Monoolefines are formed, which are returned to the contact area, and diolefines. The oxygen of the catalyst is used up in the process, so that this has to be regenerated by a gas rich in oxygen at intervals. In order to avoid oxidation cracking by the oxygen, the catalyst must be flushed with an inert gas before reuse. Dehydration occurs in a fluidised bed, where the yield of olefines is increased by dilution of the hydrocarbons by an inert gas.

Cobalt-Doped Carbon Gels as Electro-Catalysts for the Reduction of CO2 to Hydrocarbons

Directory of Open Access Journals (Sweden)

Abdalla Abdelwahab

2017-01-01

Full Text Available Two original series of carbon gels doped with different cobalt loadings and well-developed mesoporosity, aerogels and xerogels, have been prepared, exhaustively characterized, and tested as cathodes for the electro-catalytic reduction of CO2 to hydrocarbons at atmospheric pressure. Commercial cobalt and graphite sheets have also been tested as cathodes for comparison. All of the doped carbon gels catalyzed the formation of hydrocarbons, at least from type C1 to C4. The catalytic activity depends mainly on the metal loading, nevertheless, the adsorption of a part of the products in the porous structure of the carbon gel cannot be ruled out. Apparent faradaic efficiencies calculated with these developed materials were better that those obtained with a commercial cobalt sheet as a cathode, especially considering the much lower amount of cobalt contained in the Co-doped carbon gels. The cobalt-carbon phases formed in these types of doped carbon gels improve the selectivity to C3-C4 hydrocarbons formation, obtaining even more C3 hydrocarbons than CH4 in some cases.

Reaction of active uranium and thorium with aromatic carbonyls and pinacols in hydrocarbon solvents

International Nuclear Information System (INIS)

Kahn, B.E.; Rieke, R.D.

1988-01-01

Highly reactive uranium and thorium metal powders have been prepared by reduction of the anhydrous metal(IV) chlorides in hydrocarbon solvents. The reduction employs the crystalline hydrocarbon-soluble reducing agent [(TMEDA)Li] 2 [Nap] (TMEDA = N,N,N',N'-tetramethylethylenediamine, Nap = naphthalene). The resulting active metal powders have been shown to be extremely reactive with oxygen-containing compounds and have been used in the reductive coupling of aromatic ketones giving tetra-arylethylenes. Reactions with pinacols have given some mechanistic insight into the ketone coupling reaction. These finely divided metal powders activate very weakly acidic C-H bonds forming metal hydrides, which can be transferred to organic substrates

The combined effects of additives and supports on the synthesis of oxygenates over supported rhodium

International Nuclear Information System (INIS)

Chuang, S.C.; Tian, Y.; Goodwin, J.G. Jr.; Wender, I.

1985-01-01

There are potential advantages in the use of synthesis gas for the selective synthesis of oxygenated compounds rather than of hydrocarbons. This is due to the more versatile applications and higher value of oxygenates compared with that of hydrocarbons. Rh is known to be active in catalyzing, both heterogeneously and homogeneously, the formation of oxygenated compounds from synthesis gas. In a heterogeneous reaction system, the activity and selectivity of Rh catalysts are very sensitive to the chemical environment of Rh. By modifying its chemical environment through the use of various supports and/or with the addition of different promoters, Rh can selectively produce mostly oxygenates or mostly hydrocarbons. Studies have been carried out aimed at delineating the possible routes and intermediates involved in the formation of oxygenates and the function of additives (alkali promoters) and supports in the synthesis of oxygenates. Among the unpromoted Rh, the C/sub 2/ oxygenate selectivity decreased in the order: Rh/SiO/sub 2/ > Rh/MgO > Rh/La/sub 2/O/sub 3/ > Rh black, Rh/TiO/sub 2/ > Rh/Al/sub 2/O/sub 3/. High pressures improve selectivity to C/sub 2/ oxygenate compounds. Suppression of hydrogenation and ethanol dehydration was identified as major effects of alkali promotion. CO insertion was found to be dependent on both alkali promoters and on the supports. Results of ethanol addition indicated that the alkali species are located on both the Rh metal and on the support. The reaction network of CO hydrogenation on variously promoted catalysts is delineated, and the effect of secondary reactions on the overall product distribution is discussed

Prospects of Fe/MCM-41 as a Catalyst for Hydrocarbon Synthesis

International Nuclear Information System (INIS)

Cagnoli, Maria V.; Gallegos, Norma G.; Bengoa, Jose F.; Alvarez, Ana M.; Marchetti, Sergio G.; Moreno, Sergio M. J.; Roig, Anna; Mercader, Roberto C.

2005-01-01

We report the synthesis of cylindrical nanoparticles of metallic Fe entirely included in MCM-41 pores. Their dimensions are approx.3 nm diameter and approx. 3.8 nm length. We show that a coherent analysis of the results yielded by the various techniques is essential to obtain a catalyst supported on an MCM-41 matrix of ≅ 3 nm average pore diameter, which is active and selective toward olefins. The solids were characterized by low-angle x-ray diffraction, high-resolution transmission electron microscopy, high-resolution scanning transmission electron microscopy equipped with a high-angle annular dark-field, CO chemisorption, volumetric oxidation, and Moessbauer spectroscopy (in controlled atmosphere for the reduced catalysts). Catalytic results in the Fischer-Tropsch synthesis, as well as some unexpected results --like the inhomogeneous pore filling and discontinuous Fe particles-- are also discussed

Detection of hydrocarbons in irradiated foods

International Nuclear Information System (INIS)

Miyahara, Makoto; Maitani, Tamio; Saito, Akiko; Kamimura, Tomomi; Nagasawa, Taeko; Kobayashi, Yasuo; Ito, Hitoshi

2003-01-01

The hydrocarbon method for the detection of irradiated foods is now recognized as the international technique. This method is based on radiolysis of fatty acids in food to give hydrocarbons. In order to expand this technique's application, ten foods (butter, cheese, chicken, pork, beef, tuna, dry shrimp, avocado, papaya, and mango) were irradiated in the range from 0.5 to 10 kGy and the hydrocarbons in them were detected. Recoveries of the hydrocarbons from most foods were acceptable (38-128%). Some hydrocarbons were found in non-irradiated foods, particularly, in butter, cheese, tuna, and shrimp. Seven irradiated foods, butter, cheese, chicken, beef, pork, tuna, dry shrimp, and avocado were detectable at their practical doses by measuring the appropriate marker hydrocarbons. In most case, marker hydrocarbon will be 1,7-hexadecadiene. However, the marker hydrocarbons produced only in irradiated foods varied from food to food; therefore, it is necessary to check a specific irradiated food for marker hydrocarbons. On the other hand, two irradiated foods (papaya and mango which were irradiated at their practical doses) were difficult to distinguish from non-irradiated foods using this method. (author)

Detection of hydrocarbons in irradiated foods

Energy Technology Data Exchange (ETDEWEB)

Miyahara, Makoto; Maitani, Tamio [National Inst. of Health Sciences, Tokyo (Japan); Saito, Akiko; Kamimura, Tomomi; Nagasawa, Taeko [Kitasato Univ., Sagamihara, Kanagawa (Japan). School of Allied Health Sciences; Kobayashi, Yasuo; Ito, Hitoshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Establishment

2003-06-01

The hydrocarbon method for the detection of irradiated foods is now recognized as the international technique. This method is based on radiolysis of fatty acids in food to give hydrocarbons. In order to expand this technique's application, ten foods (butter, cheese, chicken, pork, beef, tuna, dry shrimp, avocado, papaya, and mango) were irradiated in the range from 0.5 to 10 kGy and the hydrocarbons in them were detected. Recoveries of the hydrocarbons from most foods were acceptable (38-128%). Some hydrocarbons were found in non-irradiated foods, particularly, in butter, cheese, tuna, and shrimp. Seven irradiated foods, butter, cheese, chicken, beef, pork, tuna, dry shrimp, and avocado were detectable at their practical doses by measuring the appropriate marker hydrocarbons. In most case, marker hydrocarbon will be 1,7-hexadecadiene. However, the marker hydrocarbons produced only in irradiated foods varied from food to food; therefore, it is necessary to check a specific irradiated food for marker hydrocarbons. On the other hand, two irradiated foods (papaya and mango which were irradiated at their practical doses) were difficult to distinguish from non-irradiated foods using this method. (author)

Cobalt supported on carbon nanofibers as catalysts for the Fischer-Tropsch synthesis

NARCIS (Netherlands)

Bezemer, G.L.

2006-01-01

The Fischer-Tropsch (FT) process converts synthesis gas (H2/CO) over a heterogeneous catalyst into hydrocarbons. Generally, cobalt catalysts supported on oxidic carriers are used for the FT process, however it appears to be difficult to obtain and maintain fully reduced cobalt particles. To overcome

Dispersion, sorption and photodegradation of petroleum hydrocarbons in dispersant-seawater-sediment systems.

Science.gov (United States)

Zhao, Xiao; Liu, Wen; Fu, Jie; Cai, Zhengqing; O'Reilly, S E; Zhao, Dongye

2016-08-15

This work examined effects of model oil dispersants on dispersion, sorption and photodegradation of petroleum hydrocarbons in simulated marine systems. Three dispersants (Corexit 9500A, Corexit 9527A and SPC 1000) were used to prepare dispersed water accommodated oil (DWAO). While higher doses of dispersants dispersed more n-alkanes and PAHs, Corexit 9500A preferentially dispersed C11-C20 n-alkanes, whereas Corexit 9527A was more favorable for smaller alkanes (C10-C16), and SPC 1000 for C12-C28 n-alkanes. Sorption of petroleum hydrocarbons on sediment was proportional to TPH types/fractions in the DWAOs. Addition of 18mg/L of Corexit 9500A increased sediment uptake of 2-3 ring PAHs, while higher dispersant doses reduced the uptake, due to micelle-enhanced solubilization effects. Both dispersed n-alkanes and PAHs were susceptible to photodegradation under simulated sunlight. For PAHs, both photodegradation and photo-facilitated alkylation were concurrently taking place. The information can facilitate sounder assessment of fate and distribution of dispersed oil hydrocarbons in marine systems. Copyright © 2016 Elsevier Ltd. All rights reserved.

Degradation of hydrocarbons in soil samples analyzed within accepted analytical holding times

International Nuclear Information System (INIS)

Jackson, J.; Thomey, N.; Dietlein, L.F.

1992-01-01

Samples which are collected in conjunction with subsurface investigations at leaking petroleum storage tank sites and petroleum refineries are routinely analyzed for benzene, toluene, ethylbenzene, xylenes (BTEX), and total petroleum hydrocarbons (TPH). Water samples are preserved by the addition of hydrochloric acid and maintained at four degrees centigrade prior to analysis. This is done to prevent bacterial degradation of hydrocarbons. Chemical preservation is not presently performed on soil samples. Instead, the samples are cooled and maintained at four degrees centigrade. This study was done to measure the degree of degradation of hydrocarbons in soil samples which are analyzed within accepted holding times. Soil samples were collected and representative subsamples were prepared from the initial sample. Subsamples were analyzed in triplicate for BTEX and TPH throughout the length of the approved holding times to measure the extent of sample constituent degradation prior to analysis. Findings imply that for sandy soils, BTEX and TPH concentrations can be highly dependent upon the length of time which elapses between sample collection and analysis

Tolerance of Antarctic soil fungi to hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Hughes, Kevin A.; Bridge, Paul; Clark, Melody S. [British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge CB3 0ET (United Kingdom)

2007-01-01

Little is known about the effects of hydrocarbons and fuel oil on Antarctic filamentous fungi in the terrestrial Antarctic environment. Growth of fungi and bacteria from soils around Rothera Research Station (Adelaide Island, Antarctic Peninsula) was assessed in the presence of ten separate aromatic and aliphatic hydrocarbons [marine gas oil (MGO), dodecane, hexadecane, benzoic acid, p-hydroxybenzoic acid, toluene, phenol, biphenyl, naphthalene and m- and p-xylenes with ethylbenzene]. Aromatic hydrocarbons inhibited soil microbial growth more than aliphatic hydrocarbons. Soil microorganisms from a moss patch, where little previous impact or hydrocarbon contamination had occurred, were less tolerant of hydrocarbons than those from high impact sites. Fungal growth rates of Mollisia sp., Penicillium commune, Mortierella sp., Trichoderma koningii, Trichoderma sp. and Phoma herbarum were assessed in the presence of hydrocarbons. Generally, aromatic hydrocarbons inhibited or stopped hyphal extension, though growth rates increased with some aliphatic hydrocarbons. Hyphal dry weight measurements suggested that Mortierella sp. may be able to use dodecane as sole carbon and energy source. Hydrocarbon-degrading Antarctic fungi may have use in future hydrocarbon spill bioremediation. (author)

Radiation chemical synthesis

International Nuclear Information System (INIS)

Zagoretz, P.A.; Poluetkov, V.A.; Shostenko, A.G.

1986-01-01

The authors consider processes in radiation chemical synthesis which are being developed in various scientific-research organizations. The important advantages of radiation chlorination, viz. the lower temperature compared with the thermal method and the absence of dehydrochlorination products are discussed. The authors examine the liquid-phase chlorination of trifluorochloroethyltrichloromethyl ether to obtain the pentachloro-contining ether, trifluorodichloroethyltrichloromethyl ether. The authors discuss radiation synthesis processes that have be used formulated kinetic equations on which models have been based. It is concluded that the possibilities of preparative (micro- and low-tonnage) radiation synthesis are promising

Synthesis and identification of organic components of 'Red Oil' (contact research)

International Nuclear Information System (INIS)

Miyata, Teijiro; Takada, Junichi; Nakagiri, Naotaka; Koike, Tadao; Tsukamoto, Michio; Watanabe, Koji; Nishio, Gunji

1999-05-01

To make clear the organic constituents of the energetic material described as 'Red Oil', laboratory studies were made on the synthesis and identification of chemical constituents of the materials obtained in the synthesis. In the studies, the synthesis was made using a variety of solvent systems (100%TBP/HNO 3 , 100%TBP/HNO 3 /U, 30%TBP/70%n-Dodecane/HNO 3 , 30%TBP/70%n-Dodecane/HNO 3 /U) with an experimental apparatus (1.0 liter under) under conditions, e.g., a temperature range 129 - 192degC and a reaction time 90 - 270 minutes, and GC and GC/MS techniques were mainly used for the identification. A GC analysis showed that the 'Red Oil' prepared from a solvent system (30%TBP/70%n-Dodecane/HNO 3 ) should comprised more than 150 degraded products, 94 products of which were identified purely by a GC/MS technique. Major components found, except for TBP and n-Dodecane being used as the starting materials, were mono- and di-nitro compounds of them, dodecanones, n-butyl nitrate, DBP and MBP. The quantitative analysis of gases formed in the 'Red Oil' synthesis experiments showed that they consisted of various compounds, the order of decreasing content in volume % were NO 2 (23 - 50), CO 2 (17 - 34), N 2 O(5.5 - 15), N 2 (4.3 - 12), CO(4 - 12), NO(1.5 - 8), and hydrocarbons (0.7 - 1.2), and that no detectable presence of O 2 and N 2 . Most of the components in the distillated volatiles collected in the condenser were n-botyl nitrate, but n-butanol were found in relatively small quantities. No significant effect of uranyl nitrate was found on the organic constituents in the 'Red Oil' synthesized. (author)

Synthesis and identification of organic components of `Red Oil` (contact research)

Energy Technology Data Exchange (ETDEWEB)

Miyata, Teijiro [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Takada, Junichi; Nakagiri, Naotaka; Koike, Tadao; Tsukamoto, Michio; Watanabe, Koji; Nishio, Gunji

1999-05-01

To make clear the organic constituents of the energetic material described as `Red Oil`, laboratory studies were made on the synthesis and identification of chemical constituents of the materials obtained in the synthesis. In the studies, the synthesis was made using a variety of solvent systems (100%TBP/HNO{sub 3}, 100%TBP/HNO{sub 3}/U, 30%TBP/70%n-Dodecane/HNO{sub 3}, 30%TBP/70%n-Dodecane/HNO{sub 3}/U) with an experimental apparatus (1.0 liter under) under conditions, e.g., a temperature range 129 - 192degC and a reaction time 90 - 270 minutes, and GC and GC/MS techniques were mainly used for the identification. A GC analysis showed that the `Red Oil` prepared from a solvent system (30%TBP/70%n-Dodecane/HNO{sub 3}) should comprised more than 150 degraded products, 94 products of which were identified purely by a GC/MS technique. Major components found, except for TBP and n-Dodecane being used as the starting materials, were mono- and di-nitro compounds of them, dodecanones, n-butyl nitrate, DBP and MBP. The quantitative analysis of gases formed in the `Red Oil` synthesis experiments showed that they consisted of various compounds, the order of decreasing content in volume % were NO{sub 2} (23 - 50), CO{sub 2} (17 - 34), N{sub 2}O(5.5 - 15), N{sub 2}(4.3 - 12), CO(4 - 12), NO(1.5 - 8), and hydrocarbons (0.7 - 1.2), and that no detectable presence of O{sub 2} and N{sub 2}. Most of the components in the distillated volatiles collected in the condenser were n-botyl nitrate, but n-butanol were found in relatively small quantities. No significant effect of uranyl nitrate was found on the organic constituents in the `Red Oil` synthesized. (author)

Production of light hydrocarbons, etc. [from heavy hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

1937-10-07

A process is given for the production of light hydrocarbons of the gasoline type and, if desired, of the middle-oil type, from liquid or fusible heavy or medium heavy hydrocarbon materials. The process comprises subjecting the said initial materials in the first stage to catalytic hydrofining, separating the lower boiling constituents and the hydrogenating gas from the resulting products and then subjecting the higher boiling constituents in a second stage to a splitting destructive hydrogenation and then recycling substantially the entire reaction mixture obtained in the second stage to the frst stage.

Rare earths: preparation of spectro chemically pure standards, study of their carbonates and synthesis of a new compound series - the peroxy carbonates

International Nuclear Information System (INIS)

Queiroz, Carlos Alberto da Silva

1996-05-01

In this work the following studies are concerned: I) preparation of lanthanum, cerium, praseodymium, neodymium and samarium oxides for use as spectro chemically pure standards; II) behavior of the rare earth (La, Ce, Pr, Nd, Sm) carbonates soluble in ammonium carbonate and mixture of ammonium carbonate/ammonium hydroxide, and III) synthesis and characterization of rare earth peroxy carbonates - a new series of compounds. Data for the synthesis and characterization of the rare earths peroxy carbonates described for the first time in this work are presented and discussed. With the aid of thermal analysis (TG-DTG) the thermal stability and the stoichiometric composition for new compounds were established and a mechanism of thermal decomposition was proposed. The peroxy carbonate was prepared by the addition of hydrogen peroxyde to the complexed soluble rare earths carbonates. These studies included also the determinations of active oxygen, the total rare earth oxide by gravimetry and complexometry and the C, H and N contents by microanalysis. The new compounds were also investigated by infrared spectroscopy. (author)

New synthesis parameters of GGG:Nd nanocrystalline powder prepared by sol–gel method: Structural and spectroscopic investigation

Energy Technology Data Exchange (ETDEWEB)

Alshikh Mohamad, Yassin, E-mail: yassinm@mail.ru; Atassi, Yomen; Moussa, Zafer

2015-09-15

GGG:Nd nanopowder is synthesized by the sol–gel method using formic acid and acetic acid as chelating agents and ethylene glycol as a cross linking agent. TGA–DSC, XRD, photoluminescence spectroscopy and fluorescence life time analysis (τ) are used to characterize the powder. XRD is used to optimize the synthesis parameters. According to XRD, complete phase of GGG nanopowder is formed at 800 °C for 1 min. Fluorescence life time analyses reveal that the optimum crystallization temperature is 1000 °C. - Highlights: • GGG:Nd nanopowder was prepared using formic acid by the sol gel method. • Optimization of sol gel parameters was done. • GGG phase formation was complete at 800 °C for 1 min • According to τ measurements, optimal temperature treatment is at 1000 °C. • Nanopowder prepared with formic acid was better than that formed with acetic acid.

Alternative Fuel Research in Fischer-Tropsch Synthesis

Science.gov (United States)

Surgenor, Angela D.; Klettlinger, Jennifer L.; Yen, Chia H.; Nakley, Leah M.

2011-01-01

NASA Glenn Research Center has recently constructed an Alternative Fuels Laboratory which is solely being used to perform Fischer-Tropsch (F-T) reactor studies, novel catalyst development and thermal stability experiments. Facility systems have demonstrated reliability and consistency for continuous and safe operations in Fischer-Tropsch synthesis. The purpose of this test facility is to conduct bench scale Fischer-Tropsch (F-T) catalyst screening experiments while focusing on reducing energy inputs, reducing CO2 emissions and increasing product yields within the F-T process. Fischer-Tropsch synthesis is considered a gas to liquid process which reacts syn-gas (a gaseous mixture of hydrogen and carbon monoxide), over the surface of a catalyst material which is then converted into liquids of various hydrocarbon chain length and product distributions1. These hydrocarbons can then be further processed into higher quality liquid fuels such as gasoline and diesel. The experiments performed in this laboratory will enable the investigation of F-T reaction kinetics to focus on newly formulated catalysts, improved process conditions and enhanced catalyst activation methods. Currently the facility has the capability of performing three simultaneous reactor screening tests, along with a fourth fixed-bed reactor used solely for cobalt catalyst activation.

Application of sunflower stalk-carbon nitride nanosheets as a green sorbent in the solid-phase extraction of polycyclic aromatic hydrocarbons followed by high-performance liquid chromatography.

Science.gov (United States)

Marzi Khosrowshahi, Elnaz; Razmi, Habib

2018-02-08

A green biocomposite of sunflower stalks and graphitic carbon nitride nanosheets has been applied as a solid-phase extraction adsorbent for sample preparation of five polycyclic aromatic hydrocarbons in different solutions using high-performance liquid chromatography with ultraviolet detection. Before the modification, sunflower stalks exhibited relatively low adsorption to the polycyclic aromatic hydrocarbons extraction. The modified sunflower stalks showed increased adsorption to the analytes extraction due to the increase in surface and existence of a π-π interaction between the analytes and graphitic carbon nitride nanosheets on the surface. Under the optimal conditions, the limits of detection and quantification for five polycyclic aromatic hydrocarbons compounds could reach 0.4-32 and 1.2-95 ng/L, respectively. The method accuracy was evaluated using recovery measurements in spiked real samples and good recoveries from 71 to 115% with relative standard deviations of polycyclic aromatic hydrocarbons determination in various samples-well water, tap water, soil, vegetable, and barbequed meat (kebab)-with analytes contents ranging from 0.065 to 13.3 μg/L. The prepared green composite as a new sorbent has some advantages including ease of preparation, low cost, and good reusability. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Process for the manufacture of a gas largely free of inert gases for synthesis. Verfahren zur Herstellung eines weitgehend inertfreien Gases zur Synthese

Energy Technology Data Exchange (ETDEWEB)

Eisenlohr, K H; Gaensslen, H; Kriebel, M; Tanz, H

1983-11-10

In a process for producing a gas largely free of inert gases for the synthesis of alcohols, particularly methanol, and of hydrocarbons from coal or heavy hydrocarbons by gasification under pressure with oxygen and steam, the crude gas is cooled, the impurities are removed by washing with methanol and the methanol is removed from the cold pure gas by molecular sieves. The pure gas is then cooled further by evaporation and methane is distilled from the liquid part while simultaneously obtaining the synthetic gas consisting of hydrogen and carbon monoxide which is largely free of methane. The methane is wholly or partly compressed and then split into carbon monoxide and hydrogen using steam and oxygen. The split gas is fed back and mixed with the synthesis gas or the partly cleaned crude gas. The synthesis gas heated to the ambient temperature, freed of impurities and free of methane is compressed to the required synthesis pressure.

The effect of reactor geometry on the synthesis of graphene materials in plasma jets

Science.gov (United States)

Shavelkina, M. B.; Amirov, R. H.; Shatalova, T. B.

2017-05-01

The possibility of synthesis of graphene and graphane (hydrogenated graphene) using the decomposition of hydrocarbons by thermal plasma has been investigated. Investigations of the influence of the plasma-forming gas on the efficiency of synthesis and the morphology of graphene materials were carried out. The synthesis products have been characterized by the methods of scanning microscopy, Raman spectroscopy and thermal analysis. It is found that the morphology of graphene materials is affected by the geometry of the reactor. It was demonstrated that the obtained graphene materials are uniformly distributed in the volume of plastic based on cyanate ester resins under mixing.

Influence of dispersants on trophic transfer of petroleum hydrocarbons in a marine food chain

Energy Technology Data Exchange (ETDEWEB)

Wolfe, M.; Tjeerdema, R. [Univ. of California, Santa Cruz, CA (United States). Dept. of Chemistry and Biochemistry; Sowby, M. [California Dept. of Fish and Game, Sacramento, CA (United States)

1995-12-31

When crude oil is accidentally released into the ocean, it threatens many levels of marine life. Intervention, in the form of chemical dispersing agents, alters the normal behavior of petroleum hydrocarbons (PH) by increasing their functional water solubility and the extent of their exposure to sub-surface organisms. Dispersing agents may modify bioavailability as a result of altered interactions between dispersed PH droplets and organismal cell membranes.The objective of this research was to determine the impact of dispersing agents on PH bioavailability and trophic transfer in primary levels of a marine food chain. Uptake, bioaccumulation, depuration, and metabolic transformation of a model PH, {sup 14}C-naphthalene, were measured and compared for Prudhoe Bay Crude Oil (PBCO) dispersed with Corexit 9527 and undispersed preparations of the water-accommodated fractions (WAF) of PBCO at two salinities and temperatures. The model food chain consisted of Isochrysis galbana and Brachionus plicatilis. Direct aqueous exposure was compared with combined aqueous and dietary exposure. Fractionation and identification of metabolites was done by HPLC co-chromatography with analytical standards, and quantitation was done by liquid scintillation counting. GC-FID characterization of WAF and dispersed oil (DO) preparations shows higher concentrations of petroleum hydrocarbons and a greater number of individual constituents in the dispersed oil preparations.

Influence of dispersants on trophic transfer of petroleum hydrocarbons in a marine food chain

International Nuclear Information System (INIS)

Wolfe, M.; Tjeerdema, R.

1995-01-01

When crude oil is accidentally released into the ocean, it threatens many levels of marine life. Intervention, in the form of chemical dispersing agents, alters the normal behavior of petroleum hydrocarbons (PH) by increasing their functional water solubility and the extent of their exposure to sub-surface organisms. Dispersing agents may modify bioavailability as a result of altered interactions between dispersed PH droplets and organismal cell membranes.The objective of this research was to determine the impact of dispersing agents on PH bioavailability and trophic transfer in primary levels of a marine food chain. Uptake, bioaccumulation, depuration, and metabolic transformation of a model PH, 14 C-naphthalene, were measured and compared for Prudhoe Bay Crude Oil (PBCO) dispersed with Corexit 9527 and undispersed preparations of the water-accommodated fractions (WAF) of PBCO at two salinities and temperatures. The model food chain consisted of Isochrysis galbana and Brachionus plicatilis. Direct aqueous exposure was compared with combined aqueous and dietary exposure. Fractionation and identification of metabolites was done by HPLC co-chromatography with analytical standards, and quantitation was done by liquid scintillation counting. GC-FID characterization of WAF and dispersed oil (DO) preparations shows higher concentrations of petroleum hydrocarbons and a greater number of individual constituents in the dispersed oil preparations

Infrared transmission study of lanthanide fullerides SmxC60 prepared by metal vapor synthesis

International Nuclear Information System (INIS)

Zhao, W.; Simmons, W.B. Jr.; Sweany, R.L.

1997-01-01

Lanthanide fulleride Sm x C 60 films were prepared by metal vapor synthesis and the valence state of the C 60 cage in the films was investigated by infrared transmission spectroscopy. Three films with different doping contents of Sm showed red-shift frequencies of F 1u (4) at 1347, 1362 and 1392 (1411) cm -1 , respectively, indicating that the major phase with corresponding valence state n∼-5, -3 and -1 might exist in the films. The other major additional feature of activated pentagonal pinch mode A g (2) was observed at 1445 or 1448 cm -1 in the films, which suggested that the Sm atoms might bond to the five-membered ring of the C 60 cage and ferrocene-like Sm x C 60 complexes might be formed. (orig.)

Adsorption of volatile hydrocarbons in iron polysulfide chalcogels

KAUST Repository

Ahmed, Ejaz

2014-11-01

We report the synthesis, characterization and possible applications of three new metal-chalcogenide aerogels KFe3Co3S 21, KFe3Y3S22 and KFe 3Eu3S22. Metal acetates react with the alkali metal polychalcogenides in formamide/water mixture to form extended polymeric frameworks that exhibit gelation phenomena. Amorphous aerogels obtained after supercritical CO2 drying have BET surface area from 461 to 573 m 2/g. Electron microscopy images and nitrogen adsorption measurements showed that pore sizes are found in micro (below 2 nm), meso (2-50 nm), and macro (above 50 nm) porous regions. These chalcogels possess optical bandgaps in the range of 1.55-2.70 eV. These aerogels have been studied for the adsorption of volatile hydrocarbons and gases. A much higher adsorption of toluene in comparison with cyclohexane and cyclopentane vapors have been observed. The adsorption capacities of the three volatile hydrocarbons are found in the following order: toluene > cyclohexane > cyclopentane. It has been observed that high selectivity in adsorption is feasible with high-surface-area metal chalcogenides. Similarly, almost an eight to ten times increase in adsorption selectivity towards CO2 over H2/CH4 was observed in the aerogels. Moreover, reversible ion-exchange properties for K+/Cs+ ions have also been demonstrated. © 2014 Elsevier Inc. All rights reserved.

Versatility of hydrocarbon production in cyanobacteria.

Science.gov (United States)

Xie, Min; Wang, Weihua; Zhang, Weiwen; Chen, Lei; Lu, Xuefeng

2017-02-01

Cyanobacteria are photosynthetic microorganisms using solar energy, H 2 O, and CO 2 as the primary inputs. Compared to plants and eukaryotic microalgae, cyanobacteria are easier to be genetically engineered and possess higher growth rate. Extensive genomic information and well-established genetic platform make cyanobacteria good candidates to build efficient biosynthetic pathways for biofuels and chemicals by genetic engineering. Hydrocarbons are a family of compounds consisting entirely of hydrogen and carbon. Structural diversity of the hydrocarbon family is enabled by variation in chain length, degree of saturation, and rearrangements of the carbon skeleton. The diversified hydrocarbons can be used as valuable chemicals in the field of food, fuels, pharmaceuticals, nutrition, and cosmetics. Hydrocarbon biosynthesis is ubiquitous in bacteria, yeasts, fungi, plants, and insects. A wide variety of pathways for the hydrocarbon biosynthesis have been identified in recent years. Cyanobacteria may be superior chassis for hydrocabon production in a photosynthetic manner. A diversity of hydrocarbons including ethylene, alkanes, alkenes, and terpenes can be produced by cyanobacteria. Metabolic engineering and synthetic biology strategies can be employed to improve hydrocarbon production in cyanobacteria. This review mainly summarizes versatility and perspectives of hydrocarbon production in cyanobacteria.

Hydrocarbon storage caverns overhaul: A case study

Energy Technology Data Exchange (ETDEWEB)

McDougall, N. [Bayer Inc., Sarnia, ON (Canada)

1998-09-01

Case studies of four hydrocarbon storage cavern overhauls by Bayer Inc., of Sarnia during the period 1993 to 1997 were reviewed and the lessons learned were discussed. Discussions included inspection requirements for each of the caverns, the logistics and planning plant production around the cavern outages, site and cavern preparation, including removal of the casing slips from the well heads. It was emphasized that cavern overhauls can be expensive operations, unless preceded by proper planning. The largest variable cost is likely to be rig time at about $ 2,000 per day. Planning for the unexpected with thoughtful contingencies can reduce costs and avoid expensive delays.

Hydrocarbon Plume Dynamics in the Worldś Most Spectacular Hydrocarbon Seeps, Santa Barbara Channel, California

Science.gov (United States)

Mau, S.; Reed, J.; Clark, J.; Valentine, D.

2006-12-01

Large quantities of natural gas are emitted from the seafloor into the coastal ocean near Coal Oil Point, Santa Barbara Channel (SBC), California. Methane, ethane, and propane were quantified in the surface water at 79 stations in a 270 km2 area in order to map the surficial hydrocarbon plume and to quantify air-sea exchange of these gases. A time series was initiated for 14 stations to identify the variability of the mapped plume, and biologically-mediated oxidation rates of methane were measured to quantify the loss of methane in surface water. The hydrocarbon plume was found to comprise ~70 km2 and extended beyond study area. The plume width narrowed from 3 km near the source to 0.7 km further from the source, and then expanded to 6.7 km at the edge of the study area. This pattern matches the cyclonic gyre which is the normal current flow in this part of the Santa Barbara Channel - pushing water to the shore near the seep field and then broadening the plume while the water turns offshore further from the source. Concentrations of gaseous hydrocarbons decrease as the plume migrates. Time series sampling shows similar plume width and hydrocarbon concentrations when normal current conditions prevail. In contrast, smaller plume width and low hydrocarbon concentrations were observed when an additional anticyclonic eddy reversed the normal current flow, and a much broader plume with higher hydrocarbon concentrations was observed during a time of diminished speed within the current gyre. These results demonstrate that surface currents control hydrocarbon plume dynamics in the SBC, though hydrocarbon flux to the atmosphere is likely less dependent on currents. Estimates of air- sea hydrocarbon flux and biological oxidation rates will also be presented.

Characterization of hydrocarbon-degrading and biosurfactant-producing Pseudomonas sp. P-1 strain as a potential tool for bioremediation of petroleum-contaminated soil.

Science.gov (United States)

Pacwa-Płociniczak, Magdalena; Płaza, Grażyna Anna; Poliwoda, Anna; Piotrowska-Seget, Zofia

2014-01-01

The Pseudomonas sp. P-1 strain, isolated from heavily petroleum hydrocarbon-contaminated soil, was investigated for its capability to degrade hydrocarbons and produce a biosurfactant. The strain degraded crude oil, fractions A5 and P3 of crude oil, and hexadecane (27, 39, 27 and 13% of hydrocarbons added to culture medium were degraded, respectively) but had no ability to degrade phenanthrene. Additionally, the presence of gene-encoding enzymes responsible for the degradation of alkanes and naphthalene in the genome of the P-1 strain was reported. Positive results of blood agar and methylene blue agar tests, as well as the presence of gene rhl, involved in the biosynthesis of rhamnolipid, confirmed the ability of P-1 for synthesis of glycolipid biosurfactant. 1H and 13C nuclear magnetic resonance, Fourier transform infrared spectrum and mass spectrum analyses indicated that the extracted biosurfactant was affiliated with rhamnolipid. The results of this study indicate that the P-1 and/or biosurfactant produced by this strain have the potential to be used in bioremediation of hydrocarbon-contaminated soils.

Polynuclear Aromatic Hydrocarbons with Curved Surfaces: Buckyballs

Energy Technology Data Exchange (ETDEWEB)

Sygula, Andrzej [Mississippi State Univ., Mississippi State, MS (United States)

2016-08-15

The discovery of a new allotropic form of elemental carbon – the fullerenes – and subsequently other novel forms of elemental carbon with pyramidalized surfaces, most notably single-walled and multi-walled carbon nanotubes, introduced a novel structural motif to the polycyclic aromatic hydrocarbons (PAHs) with nonplanar surfaces. Our research program supported by BES DOE grant DE-FG02-04ER15514 has dealt with the synthesis, structural studies, and chemistry of the novel curved-surface PAHs with carbon frameworks structurally related to fullerenes. They are referred to as “buckybowls”. We prepared several new buckybowls and, even more importantly, developed the efficient, gram-scale synthetic methodologies for the preparation of small buckybowls, most notably corannulene (C20H10) and its derivatives. In addition, the employment of the corannulene-based synthons previously developed in our laboratory led to a number of highly nonplanar molecular architectures with two or more corannulene subunits with a potential for the applications as novel materials in separation sciences, nanoelectronics, photovoltaics and catalysis. In collaboration with Professor Angelici (Iowa State) we prepared and characterized several transition metal complexes of corannulene, providing the first structural characterization of η6 metal complexes of buckybowls by a single crystal X-ray diffraction. In addition to the definitive structural characterization of the complexes we demonstrated that the (η6-C6Me6)Ru2+ unit in some relatively stable complexes activate the corannulene ligand to react with proper nucleophiles suggesting that such complexex may be used in catalysis. (Section C). We have explored the efficiency of the dispersion-based interactions of curved-surface conjugated carbon networks by high-level computational models. We showed that the curvature of such networks does not reduce the van der Waals attractions as compared to the planar systems of similar size. We than

Predicting hydrocarbon release from soil

International Nuclear Information System (INIS)

Poppendieck, D.; Loehr, R.C.

2002-01-01

'Full text:' The remediation of hazardous chemicals from soils can be a lengthy and costly process. As a result, recent regulatory initiatives have focused on risk-based corrective action (RBCA) approaches. Such approaches attempt to identify the amount of chemical that can be left at a site with contaminated soil and still be protective of human health and the environment. For hydrocarbons in soils to pose risk to human heath and the environment, the hydrocarbons must be released from the soil and accessible to microorganisms, earthworms, or other higher level organisms. The sorption of hydrocarbons to soil can reduce the availability of the hydrocarbon to receptors. Typically in soils and sediments, there is an initial fast release of a hydrocarbon from the soil to the aqueous phase followed by a slower release of the remaining hydrocarbon to the aqueous phase. The rate and extent of slow release can influence aqueous hydrocarbon concentrations and the fate and transport of hydrocarbons in the subsurface. Once the fast fraction of the chemical has been removed from the soil, the remaining fraction of a chemical may desorb at a rate that natural mechanisms can attenuate the released hydrocarbon. Hence, active remediation may be needed only until the fast fraction has been removed. However, the fast fraction is a soil and chemical specific parameter. This presentation will present a tier I type protocol that has been developed to quickly estimate the fraction of hydrocarbons that are readily released from the soil matrix to the aqueous phase. Previous research in our laboratory and elsewhere has used long-term desorption (four months) studies to determine the readily released fraction. This research shows that a single short-term (less than two weeks) batch extraction procedure provides a good estimate of the fast released fraction derived from long-term experiments. This procedure can be used as a tool to rapidly evaluate the release and bioavailability of

Synthesis of extended polycyclic aromatic hydrocarbons by oxidative tandem spirocyclization and 1,2-aryl migration

Science.gov (United States)

Zhang, Xuan; Xu, Zhanqiang; Si, Weili; Oniwa, Kazuaki; Bao, Ming; Yamamoto, Yoshinori; Jin, Tienan

2017-04-01

The extended polycyclic aromatic hydrocarbons (PAHs) have received significant interdisciplinary attention due to their semiconducting applications in diverse organic electronics as well as intriguing structural interests of well-defined graphene segments. Herein, a highly efficient oxidative spirocyclization and 1,2-aryl migration tandem synthetic method for the construction of extended polyaromatic hydrocarbons (PAHs) has been developed. The CuCl-catalyst/PhCO3 tBu or DDQ oxidation system in the presence of trifluoroacetic acid enables the selective single-electron oxidation to take place preferentially at the more electron-rich alkene moiety of o-biphenylyl-substituted methylenefluorenes, giving rise to the subsequent tandem process. A variety of structurally diverse extended PAHs including functionalized dibenzo[g,p]chrysenes, benzo[f]naphtho[1,2-s]picene, hexabenzo[a,c,fg,j,l,op]tetracene, tetrabenzo[a,c,f,m]phenanthro[9,10-k]tetraphene, tetrabenzo[a,c,f,k]phenanthro[9,10-m]tetraphene, tetrabenzo[a,c,f,o]phenanthro[9,10-m]picene and S-type helicene have been readily synthesized.

Formation of microspheres under the action of femtosecond laser radiation on titanium samples in hydrocarbons

Science.gov (United States)

Kochuev, D. A.; Khorkov, K. S.; Ivashchenko, A. V.; Prokoshev, V. G.; Arakelian, S. M.

2018-01-01

This work describes the original method of laser synthesis of microspheres which contain titanium carbide. The formation of microspheres is carried out by the action of femtosecond laser radiation on the surface of titanium in the reaction medium - the ultimate hydrocarbon. The resulting microspheres have a high surface smoothness, a narrow particle size distribution, an average size of 1-3 μm. They can be used in applications of additive engineering, powder metallurgy as the main raw material, or as an alloying additive.

Hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

1927-02-22

Coal tar, mineral oils, bitumens, coal extraction products, hydrogenation products of coal, oil schists can be atomized and heated with steam to decompose pyrogenetically and form gases rich in olefins which may be heated with or without pressure and with or without catalysts to produce liquid hydrocarbons of low boiling point, some of which may be aromatic. The apparatus should be lined with copper, silica, or ferrosilicon to prevent contact of the bases with iron which causes deposition of soot. Catalysts used may be metal oxides, silica, graphite, active charcoal, mica, pumice, porcelain, barium carbonate, copper, silver, gold, chromium, boron, or their compounds. At temperatures from 300 to 400/sup 0/C, olefins are produced. At higher temperatures, naphthenes and benzene hydrocarbons are produced.

Hydrogen production with short contact time. Catalytic partial oxidation of hydrocarbons and oxygenated compounds: Recent advances in pilot- and bench-scale testing and process design

Energy Technology Data Exchange (ETDEWEB)

Guarinoni, A.; Ponzo, R.; Basini, L. [ENI Refining and Marketing Div., San Donato Milanese (Italy)

2010-12-30

ENI R and D has been active for fifteen years in the development of Short Contact Time - Catalytic Partial Oxidation (SCT-CPO) technologies for producing Hydrogen/Synthesis Gas. From the beginning the experimental work addressed either at defining the fundamental principles or the technical and economical potential of the technology. Good experimental responses, technical solutions' simplicity and flexibility, favourable techno-economical evaluations promoted the progressive widening of the field of the investigations. From Natural Gas (NG) the range of ''processable'' Hydrocarbons extended to Liquefied Petroleum Gas (LPG) and Gasoils, including those characterised by high levels of unsaturated and sulphurated molecules and, lately, to other compounds with biological origin. The extensive work led to the definition of different technological solutions, grouped as follows: Technology 1: Air Blown SCT-CPO of Gaseous Hydrocarbons and/or Light Compounds with biological origin Technology 2: Enriched Air/Oxygen Blown SCT-CPO of Gaseous Hydrocarbons and/or Light Compounds with biological origin Technology 3: Enriched Air/Oxygen Blown SCT-CPO of Liquid Hydrocarbons and/or Compounds with biological origin Recently, the licence rights on a non-exclusive basis for the commercialisation of SCT-CPO based processes for H{sub 2}/Synthesis gas production from light hydrocarbons with production capacity lower than 5,000 Nm{sup 3}/h of H{sub 2} or 7,500 Nm3/h of syngas have been assigned to two external companies. In parallel, development of medium- and large-scale plant solutions is progressing within the ENI group framework. These last activities are addressed to the utilisation of SCT-CPO for matching the variable Hydrogen demand in several contexts of oil refining operation. This paper will report on the current status of SCT-CPO with a focus on experimental results obtained, either at pilot- and bench- scale level. (orig.)

Influence of the synthesis parameters on the physico-chemical and catalytic properties of cerium oxide for application in the synthesis of diethyl carbonate

International Nuclear Information System (INIS)

Leino, Ewelina; Kumar, Narendra; Mäki-Arvela, Päivi; Aho, Atte; Kordás, Krisztián; Leino, Anne-Riikka; Shchukarev, Andrey; Murzin, Dmitry Yu.; Mikkola, Jyri-Pekka

2013-01-01

Synthesis of cerium (IV) oxide by means of room temperature precipitation method was carried out. The effect of preparation variables such as synthesis time, calcination temperature and pH of the solution on resulting CeO 2 properties was discussed. Moreover, the comparison of CeO 2 samples prepared in a static and rotation mode of synthesis is presented. The solid catalysts were characterized by means of X-ray powder diffraction, scanning electron microscopy, transmission electron microscope, nitrogen physisorption, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy using pyridine as a probe molecule and temperature programmed desorption of CO 2 . Significant variations in physico-chemical properties of CeO 2 by varying the preparation conditions were observed. Furthermore, the catalytic performances of CeO 2 catalysts were compared in the synthesis of diethyl carbonate starting from ethanol and CO 2 using butylene oxide as a dehydrating agent. The dependence of CeO 2 properties on its catalytic activity is evaluated in detail. - Highlights: • Synthesis of cerium (IV) oxide by precipitation method. • Influence of synthesis time, calcination temperature, mode of stirring and solution pH on properties. • Characterization by XRD, SEM, TEM, nitrogen physisorption, XPS, FTIR. • Catalytic performance diethyl carbonate synthesis from ethanol and CO 2

Fractional separation of hydrocarbon vapours

Energy Technology Data Exchange (ETDEWEB)

1937-07-10

A process is described for converting higher boiling hydrocarbons to lower boiling hydrocarbons by subjecting them at elevated temperatures to a conversion operation, then separating the higher and lower boiling fractions. The separation takes place while the reaction products are maintained in the vapor phase by contact with a mass of solid porous material which has little or no catalytic activity but does have a preferential absorption property for higher boiling hydrocarbons so that the lower boiling part of the reaction products pass through the separation zone while the heavier hydrocarbons are retained. The separation is accomplished without substantial loss of heat of these reaction products.

Carbon-Nickel oxide nanocomposites: Preparation and charecterisation

CSIR Research Space (South Africa)

Tile, N

2011-07-01

Full Text Available Nanocomposite materials have wide range of applications in solar energy conversion. In this work, C-NiO nanocomposite coatings are prepared using sol-gel synthesis and deposited on aluminium substrates using a spin coater. The coatings are prepared...

TiO{sub 2} on magnesium silicate monolith: effects of different preparation techniques on the photocatalytic oxidation of chlorinated hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Cardona, Ana I.; Candal, Roberto; Sanchez, Benigno; Avila, Pedro; Rebollar, Moises

2004-05-01

In this article, the comparative results of the photocatalytic oxidation of trichloroethylene (TCE) alone and a mixture of chlorinated hydrocarbons (trichloroethylene, perchloroethylene and chloroform) in gas phase, obtained with three different monolithic catalysts in a flat reactor frontally illuminated with a Xenon lamp are presented. The three catalysts incorporate titanium dioxide (TiO{sub 2}) as active phase on a magnesium silicate support, by means of different procedures: (i) incorporation of commercial TiO{sub 2} powder into the silicate matrix ('massic monolith'); (ii) sol-gel coating of the silicate support; (iii) impregnation with a commercial TiO{sub 2} aqueous suspension of the same silicate support. In the first case, the massic monolith was made from a 50:50 w/w mixture of magnesium silicate and 'Titafrance G5' TiO{sub 2} powder. In the second case, a magnesium silicate monolith was coated with several layers of an aqueous TiO{sub 2} sol prepared from hydrolysis and condensation of titanium tetra-isopropoxide (Ti(OC{sub 3}H{sub 7}){sub 4}) in excess of acidified water (acid catalysis). The third catalyst was prepared by impregnating the same silicate support with several layers of 'Titafrance G5' TiO{sub 2} powder water suspension. All the catalysts were thermal treated under comparable conditions in order to fix the TiO{sub 2} active phase to the silicate support. Although the performance of the massic monolith was better than the sol-gel monolith, the latter is of great interest because this technique allows the chemical composition of the active films to be easily modified.

Effect of pyrolysis temperature on polycyclic aromatic hydrocarbons toxicity and sorption behaviour of biochars prepared by pyrolysis of paper mill effluent treatment plant sludge.

Science.gov (United States)

Devi, Parmila; Saroha, Anil K

2015-09-01

The polycyclic aromatic hydrocarbons (PAHs) toxicity and sorption behaviour of biochars prepared from pyrolysis of paper mill effluent treatment plant (ETP) sludge in temperature range 200-700 °C was studied. The sorption behaviour was found to depend on the degree of carbonization where the fractions of carbonized and uncarbonized organic content in the biochar act as an adsorption media and partition media, respectively. The sorption and partition fractions were quantified by isotherm separation method and isotherm parameters were correlated with biochar properties (aromaticity, polarity, surface area, pore volume and ash content). The risk assessment for the 16 priority EPA PAHs present in the biochar matrix was performed and it was found that the concentrations of the PAHs in the biochar were within the permissible limits prescribed by US EPA (except BC400 and BC500 for high molecular weight PAHs). Copyright © 2015 Elsevier Ltd. All rights reserved.

Use of biolog methodology for optimizing the degradation of hydrocarbons by bacterial consortia.

Science.gov (United States)

Ambrosoli, R; Bardi, L; Minati, J L; Belviso, S; Ricci, R; Marzona, M

2003-01-01

Biolog methodology was used for the preliminary screening of different cultural conditions in order to detect the best combination/s of factors influencing the metabolic performance of bacterial consortia active in the degradation of hydrocarbons. Two microbial consortia were tested for their activity on 2 hydrocarbons (nonadecane and eicosane) in presence of the following cultural coadjuvants: vegetal oil, beta-cyclodextrine, sodium acetate, mineral solution. Tests were conducted in Biolog MT plates, where only the redox indicator of microbial growth (tetrazolium violet) and no carbon sources are provided. The microwells were filled with various combinations of hydrocarbons, microbial inoculum and coadjuvants. Blanks were prepared with the same combinations but without hydrocarbons. The results obtained show the suitability of the methodology developed to identify the most active consortium and the conditions for its best degradation performance. The efficacy of Biolog methodology (Biolog Inc., USA) for the characterization of microbial communities on the basis of the metabolic profiles obtained on specific carbon sources in the microwells of Elisa-type plates, is widely acknowledged (Garland, 1997; Pietikäinen et al., 2000; Dauber and Wolters, 2000). Due to its aptitude to simultaneously evaluate multiple microbial responses and directly organize the results, it can be adapted to meet specific study purposes (Gamo and Shji, 1999). In the present research Biolog methodology was fitted for the preliminary screening of different cultural conditions, in order to detect the best combination/s of factors influencing the metabolic performance of bacterial consortia active in the degradation of aliphatic hydrocarbons, in view of their utilization for the bioremediation of polluted sites.

Incorporation of catalytic dehydrogenation into Fischer-Tropsch synthesis to lower carbon dioxide emissions

Science.gov (United States)

Huffman, Gerald P

2012-09-18

A method for producing liquid fuels includes the steps of gasifying a starting material selected from a group consisting of coal, biomass, carbon nanotubes and mixtures thereof to produce a syngas, subjecting that syngas to Fischer-Tropsch synthesis (FTS) to produce a hyrdrocarbon product stream, separating that hydrocarbon product stream into C1-C4 hydrocarbons and C5+ hydrocarbons to be used as liquid fuels and subjecting the C1-C4 hydrocarbons to catalytic dehydrogenation (CDH) to produce hydrogen and carbon nanotubes. The hydrogen produced by CDH is recycled to be mixed with the syngas incident to the FTS reactor in order to raise the hydrogen to carbon monoxide ratio of the syngas to values of 2 or higher, which is required to produce liquid hydrocarbon fuels. This is accomplished with little or no production of carbon dioxide, a greenhouse gas. The carbon is captured in the form of a potentially valuable by-product, multi-walled carbon nanotubes (MWNT), while huge emissions of carbon dioxide are avoided and very large quantities of water employed for the water-gas shift in traditional FTS systems are saved.

Preparation of MoB and MoB-MoSi2 composites by combustion synthesis in SHS mode

International Nuclear Information System (INIS)

Yeh, C.L.; Hsu, W.S.

2007-01-01

Combustion synthesis in the mode of self-propagating high-temperature synthesis (SHS) was carried out in the Mo-B and Mo-B-Si systems for the preparation of molybdenum boride MoB and the composite of MoB-MoSi 2 from elemental powder compacts. Under a preheating temperature above 150 deg. C , the reaction of Mo with boron in the sample compact of Mo:B = 1:1 is characterized by a planar combustion front propagating in a self-sustaining and steady manner. As the preheating temperature or sample compaction density increased, combustion temperature was found to increase and the propagation rate of the combustion front was correspondingly enhanced. Moreover, the XRD analysis provides evidence of yielding nearly single-phase α-MoB from the Mo-B sample at equiatomic stoichiometry. In the synthesis of MoB-MoSi 2 composites, the starting stoichiometry of the Mo-B-Si powder compact was varied so as to produce the final composites containing 20-80 mol% MoB. It was also found the increase of flame-front velocity and combustion temperature with increasing MoB content formed in the composite. The composition analysis by XRD shows excellent conversion from the Mo-B-Si powder compact to the MoB-MoSi 2 composite through the SHS reaction; that is, in addition to a small amount of Mo 5 Si 3 , the as-synthesized composite is composed entirely of MoB and MoSi 2

Coupling of glycerol processing with Fischer-Tropsch synthesis for production of liquid fuels

DEFF Research Database (Denmark)

Simonetti, D.A.; Rass-Hansen, Jeppe; Kunkes, E.L.

2007-01-01

Liquid alkanes can be produced directly from glycerol by an integrated process involving catalytic conversion to H-2/CO gas mixtures (synthesis gas) combined with Fischer-Tropsch synthesis. Synthesis gas can be produced at high rates and selectivities suitable for Fischer-Tropsch synthesis (H-2/CO...... between 1.0 and 1.6) from concentrated glycerol feed solutions at low temperatures (548 K) and high pressures (1-17 bar) over a 10 wt% Pt-Re/C catalyst with an atomic Pt : Re ratio of 1 : 1. The primary oxygenated hydrocarbon intermediates formed during conversion of glycerol to synthesis gas are ethanol...... in the liquid organic effluent stream and increasing the selectivity to C5+ alkanes by a factor of 2 ( from 0.30 to 0.60). Catalytic conversion of glycerol and Fischer-Tropsch synthesis were coupled in a two-bed reactor system consisting of a Pt-Re/C catalyst bed followed by a Ru/TiO2 catalyst bed...

Synthesis and characterization of iron cobalt (FECO) nanorods ...

African Journals Online (AJOL)

Synthesis and characterization of iron cobalt (FECO) nanorods prepared by simple ... shaped by increasing annealing temperature from room temperature to 800 ... Keywords: FeCo nanoparticles, sodium borohydrid, CTAB, chemical synthesis ...

Synthesis, structural investigation and magnetic properties of Zn2+ substituted cobalt ferrite nanoparticles prepared by the sol–gel auto-combustion technique

International Nuclear Information System (INIS)

Raut, A.V.; Barkule, R.S.; Shengule, D.R.; Jadhav, K.M.

2014-01-01

Structural morphology and magnetic properties of the Co 1−x Zn x Fe 2 O 4 (0.0≤x≥1.0) spinel ferrite system synthesized by the sol–gel auto-combustion technique using nitrates of respective metal ions have been studied. The ratio of metal nitrates to citric acid was taken at 1:3. The as prepared powder of cobalt zinc ferrite was sintered at 600 °C for 12 h after TG/DTA thermal studies. Compositional stoichiometry was confirmed by energy dispersive analysis of the X-ray (EDAX) technique. Single phase cubic spinel structure of Co–Zn nanoparticles was confirmed by XRD data. The average crystallite size (t), lattice constant (a) and other structural parameters of zinc substituted cobalt ferrite nanoparticles were calculated from XRD followed by SEM and FTIR. It is observed that the sol–gel auto-combustion technique has many advantages for the synthesis of technologically applicable Co–Zn ferrite nanoparticles. The present investigation clearly shows the effect of the synthesis method and possible relation between magnetic properties and microstructure of the prepared samples. Increase in nonmagnetic Zn 2+ content in cobalt ferrite nanoparticles is followed by decrease in n B , M s and other magnetic parameters. Squareness ratio for the Co-ferrite was 1.096 at room temperature. - Highlights: • Co–Zn nanoparticles are prepared by sol–gel auto-combustion method. • Structural properties were characterized by XRD, SEM, and FTIR. • Compositional stoichiometry was confirmed by EDAX analysis. • Magnetic parameters were measured by the pulse field hysteresis loop technique

Characterization of hydrocarbon utilizing fungi from hydrocarbon ...

African Journals Online (AJOL)

Prof. Ogunji

isolated fungi could be useful in the bioremediation of hydrocarbon polluted sites. Keywords: ... Technologies such as mechanical force, burying, evaporation, dispersant application, and ..... The effects of drilling fluids on marine bacteria from a.

Synthesis of a jojoba bean disaccharide.

Science.gov (United States)

Kornienko, A; Marnera, G; d'Alarcao, M

1998-08-01

A synthesis of the disaccharide recently isolated from jojoba beans, 2-O-alpha-D-galactopyranosyl-D-chiro-inositol, has been achieved. The suitably protected chiro-inositol unit was prepared by an enantiospecific synthesis from L-xylose utilizing SmI2-mediated pinacol coupling as a key step.

Final technical report for the Center for Catalytic Hydrocarbon Functionalization (an EFRC)

Energy Technology Data Exchange (ETDEWEB)

Gunnoe, Thomas Brent [Univ. of Virginia, Charlottesville, VA (United States)

2016-11-11

Greater than 95% of all materials produced by the chemical industry are derived from a small slate of simple hydrocarbons that are derived primarily from natural gas and petroleum, predominantly through oxygenation, C–C bond formation, halogenation or amination. Yet, current technologies for hydrocarbon conversion are typically high temperature, multi-step processes that are energy and capital intensive and result in excessive emissions (including carbon dioxide). The Center for Catalytic Hydrocarbon Functionalization (CCHF) brought together research teams with the broad coalition of skills and knowledge needed to make the fundamental advances in catalysis required for next-generation technologies to convert hydrocarbons (particularly light alkanes and methane) at high efficiency and low cost. Our new catalyst technologies offer many opportunities including enhanced utilization of natural gas in the transportation sector (via conversion to liquid fuels), more efficient generation of electricity from natural gas using direct methane fuel cells, reduced energy consumption and waste production for large petrochemical processes, and the preparation of high value molecules for use in biological/medical applications or the agricultural sector. The five year collaborative project accelerated fundamental understanding of catalyst design for the conversion of C–H bonds to functionalized products, essential to achieve the goals listed above, as evidenced by the publication of 134 manuscripts. Many of these fundamental advancements provide a foundation for potential commercialization, as evidenced by the submission of 11 patents from research support by the CCHF.

Measuring Trace Hydrocarbons in Silanes

Science.gov (United States)

Lesser, L. A.

1984-01-01

Technique rapid and uses standard analytical equipment. Silane gas containing traces of hydrocarbons injected into carrier gas of moist nitrogen having about 0.2 percent water vapor. Carrier, water and silane pass through short column packed with powdered sodium hydroxide which combines moisture and silane to form nonvolatile sodium silicate. Carrier gas free of silane but containing nonreactive hydrocarbons, pass to silica-gel column where chromatographic separation takes place. Hydrocarbons measured by FID.

Direct-immersion solid-phase microextraction coupled to fast gas chromatography mass spectrometry as a purification step for polycyclic aromatic hydrocarbons determination in olive oil.

Science.gov (United States)

Purcaro, Giorgia; Picardo, Massimo; Barp, Laura; Moret, Sabrina; Conte, Lanfranco S

2013-09-13

The aim of the present work was to optimize a preparation step for polycyclic aromatic hydrocarbons in a fatty extract. Solid-phase microextraction is an easy preparation technique, which allows to minimize solvent consumption and reduce sample manipulation. A Carbopack Z/polydimethylsiloxane fiber, particularly suitable for extraction of planar compounds, was employed to extract polycyclic aromatic hydrocarbons from a hexane solution obtained after a previous extraction with acetonitrile from oil, followed by a liquid-liquid partition between acetonitrile and hexane. The proposed method was a rapid and sensitive solution to reduce the interference of triglycerides saving the column life and avoiding frequent cleaning of the mass spectrometer ion source. Despite the non-quantitative extraction of polycyclic aromatic hydrocarbons from oil using acetonitrile, the signal-to-noise ratio was significantly improved obtaining a limit of detection largely below the performance criteria required by the European Union legislation. Copyright © 2013 Elsevier B.V. All rights reserved.

High Temperature Chemistry of Aromatic Hydrocarbons. Final Technical Report

Energy Technology Data Exchange (ETDEWEB)

Scott, Lawrence T. [Boston College, Chestnut Hill, MA (United States). Merkert Chemistry Center, Dept. of Chemistry

2017-05-15

synthesis of C₆₀ and other fullerenes depended critically on a knowledge of hydrocarbon reactions at high temperatures in the gas phase, and the research supported by this project enabled further advances in the realm of carbon-rich materials.

Purifying hydrocarbon oils

Energy Technology Data Exchange (ETDEWEB)

Rostin, H

1938-08-11

A process is described for continuously purifying hydrocarbon oils consisting in conducting the vapors of the same at a temperature of 300 to 400/sup 0/C over the oelitic ore minette together with reducing gases in presence of steam the proportion of the reducing gases and steam being such that the sulfur of the hydrocarbons escapes from the reaction chamber in the form of sulfuretted hydrogen without permanent sulfide of iron being formed.

Laser-induced particle size tuning and structural transformations in germanium nanoparticles prepared by stain etching and colloidal synthesis route

Energy Technology Data Exchange (ETDEWEB)

Karatutlu, Ali, E-mail: a.karatutlu@qmul.ac.uk, E-mail: ali.karatutlu@bou.edu.tr [Centre for Condensed Matter and Materials Physics, School of Physics and Astronomy, Queen Mary, University of London, London E1 4NS (United Kingdom); Electrical and Electronics Engineering, Bursa Orhangazi University, 16310 Yıldırım/Bursa (Turkey); Little, William; Ersoy, Osman; Zhang, Yuanpeng; Sapelkin, Andrei [Centre for Condensed Matter and Materials Physics, School of Physics and Astronomy, Queen Mary, University of London, London E1 4NS (United Kingdom); Seker, Isa [Bio-Nanotechnology Research and Development Centre, Fatih University, 34500 Buyukcekmece, Istanbul (Turkey)

2015-12-28

In this study, with the aid of Raman measurements, we have observed transformations in small (∼3 nm and ∼10 nm) free-standing Ge nanoparticles under laser light exposure. The nanoparticles were obtained by the chemical stain etching of a monocrystalline Ge wafer and of Ge powder and by colloidal synthesis route. We found that the transformation path depends on laser power and exposure time. At relatively low values of the laser power (2 mW) over a period of 100 min, the Raman signal indicates transformation of the sample from a nanocrystaline to bulk-like state, followed by partial oxidation and finally a conversion of the entire sample into alpha-quartz type GeO{sub 2}. However, when the laser power is set at 60 mW, we observed a heat release during an explosive crystallization of the nanocrystalline material into bulk Ge without noticeable signs of oxidation. Together with the transmission electron microscopy measurements, these results suggest that the chemical stain etching method for the preparation of porous Ge may not be a top-down process as has been widely considered, but a bottom up one. Systematic studies of the laser exposure on Ge nanoparticles prepared by colloidal synthesis results in the fact that the explosive crystallisation is common for H-terminated and partially disordered Ge nanoparticles regardless of its particle size. We suggest possible bio-medical applications for the observed phenomena.

Synthesis of All-carbon Chains and Nanoparticles by Chemical Transformation of Halogenated Hydrocarbons at Low Temperatures

Czech Academy of Sciences Publication Activity Database

Kavan, Ladislav

č. 196 (2001), s. 22-38 ISSN 0371-5345 R&D Projects: GA ČR GA203/98/1168; GA ČR GA203/99/1015; GA ČR GA203/00/0634 Institutional research plan: CEZ:AV0Z4040901 Keywords : halogenated hydrocarbon * electrochemical carbon * fullerenes Subject RIV: CG - Electrochemistry

Recovering low-boiling hydrocarbons, etc

Energy Technology Data Exchange (ETDEWEB)

Pier, M

1934-10-03

A process is described for the recovery of low-boiling hydrocarbons of the nature of benzine through treatment of liquid carbonaceous materials with hydrogen under pressure at raised temperature, suitably in the presence of catalysts. Middle oils (practically saturated with hydrogen) or higher boiling oils at a temperature above 500/sup 0/ (with or without the addition of hydrogen) containing cyclic hydrocarbons not saturated with hydrogen are changed into low boiling hydrocarbons of the nature of benzine. The cracking takes place under strongly hydrogenating conditions (with the use of a strongly active hydrogenating catalyst or high pressure) at temperatures below 500/sup 0/. If necessary, the constituents boiling below 200/sup 0/ can be reconverted into cyclic hydrocarbons partially saturated with hydrogen. (BLM)

Synthesis of enantioenriched γ-quaternary cycloheptenones using a combined allylic alkylation/Stork–Danheiser approach: preparation of mono-, bi-, and tricyclic systems

KAUST Repository

Bennett, Nathan B.; Hong, Allen Y.; Harned, Andrew M.; Stoltz, Brian M.

2012-01-01

A general method for the synthesis of β-substituted and unsubstituted cycloheptenones bearing enantioenriched all-carbon γ-quaternary stereocenters is reported. Hydride or organometallic addition to a seven-membered ring vinylogous ester followed by finely tuned quenching parameters achieves elimination to the corresponding cycloheptenone. The resulting enones are elaborated to bi- and tricyclic compounds with potential for the preparation of non-natural analogs and whose structures are embedded in a number of cycloheptanoid natural products.

Enhanced gasification of wood in the presence of mixed catalysts

Energy Technology Data Exchange (ETDEWEB)

Weber, S. L.; Mudge, L. K.; Sealock, Jr., L. J.; Robertus, R. J.; Mitchell, D. E.

Experimental results obtained in laboratory investigations of steam gasification of wood in the presence of mixed catalysts are presented. These studies are designed to test the technical feasibility of producing specific gaseous products from wood by enhancing its reactivity and product specificity through the use of combined catalysts. The desired products include substitute natural gas, hydrocarbon synthesis gas and ammonia synthesis gas. The gasification reactions are controlled through the use of specific catalyst combinations and operating parameters. A primary alkali carbonate gasification catalyst impregnated into the wood combined with specific commercially available secondary catalysts produced the desired products. A yield of 50 vol % methane was obtained with a randomly mixed combination of a commercial nickel methanation catalyst and silica-alumina cracking catalyst at a weight ratio of 3:1 respectively. Steam gasification of wood in the presence of a commercial Si-Al cracking catalyst produced the desired hydrocarbon synthesis gas. Hydrogen-to-carbon monoxide ratios needed for Fischer-Tropsch synthesis of hydrocarbons were obtained with this catalyst system. A hydrogen-to-nitrogen ratio of 3:1 for ammonia synthesis gas was achieved with steam-air gasification of wood in the presence of catalysts. The most effective secondary catalyst system employed to produce the ammonia synthesis gas included two commercially prepared catalysts formulated to promote the water-gas shift reaction.

Soil sealing degree as factor influencing urban soil contamination with polycyclic aromatic hydrocarbons (PAHs

Directory of Open Access Journals (Sweden)

Mendyk Łukasz

2016-03-01

Full Text Available The objective of the study was to determine role of soil sealing degree as the factor influencing soil contamination with polycyclic aromatic hydrocarbons (PAHs. The study area included four sampling sites located within the administrative boundaries of the Toruń city, Poland. Sampling procedure involved preparing soil pits representing three examples of soil sealing at each site: non-sealed soil as a control one (I and two degrees of soil sealing: semi-pervious surface (II and totally impervious surface (III. Together with basic properties defined with standard procedures (particle size distribution, pH, LOI, content of carbonates content of selected PAHs was determined by dichloromethane extraction using gas chromatography with mass spectrometric detection (GC-MS. Obtained results show that urban soils in the city of Toruń are contaminated with polycyclic aromatic hydrocarbons. Soil sealing degree has a strong influence on the soil contamination with polycyclic aromatic hydrocarbons. Totally sealed soils are better preserved from atmospheric pollution including PAHs. Combustion of grass/wood/coal was the main source of determined PAHs content in examined soils.

Hydrous pyrolysis/oxidation process for in situ destruction of chlorinated hydrocarbon and fuel hydrocarbon contaminants in water and soil

Science.gov (United States)

Knauss, Kevin G.; Copenhaver, Sally C.; Aines, Roger D.

2000-01-01

In situ hydrous pyrolysis/oxidation process is useful for in situ degradation of hydrocarbon water and soil contaminants. Fuel hydrocarbons, chlorinated hydrocarbons, polycyclic aromatic hydrocarbons, petroleum distillates and other organic contaminants present in the soil and water are degraded by the process involving hydrous pyrolysis/oxidation into non-toxic products of the degradation. The process uses heat which is distributed through soils and water, optionally combined with oxygen and/or hydrocarbon degradation catalysts, and is particularly useful for remediation of solvent, fuel or other industrially contaminated sites.

Iron catalyst for preparation of polymethylene from synthesis gas and method for producing the catalyst

Science.gov (United States)

Sapienza, R.S.; Slegeir, W.A.

1990-05-15

This invention relates to a process for synthesizing hydrocarbons; more particularly, the invention relates to a process for synthesizing long-chain hydrocarbons known as polymethylene from carbon monoxide and hydrogen or from carbon monoxide and water or mixtures thereof in the presence of a catalyst comprising iron and platinum or palladium or mixtures thereof which may be supported on a solid material, preferably an inorganic refractory oxide. This process may be used to convert a carbon monoxide containing gas to a product which could substitute for high density polyethylene.

Syntrophic biodegradation of hydrocarbon contaminants.

Science.gov (United States)

Gieg, Lisa M; Fowler, S Jane; Berdugo-Clavijo, Carolina

2014-06-01

Anaerobic environments are crucial to global carbon cycling wherein the microbial metabolism of organic matter occurs under a variety of redox conditions. In many anaerobic ecosystems, syntrophy plays a key role wherein microbial species must cooperate, essentially as a single catalytic unit, to metabolize substrates in a mutually beneficial manner. Hydrocarbon-contaminated environments such as groundwater aquifers are typically anaerobic, and often methanogenic. Syntrophic processes are needed to biodegrade hydrocarbons to methane, and recent studies suggest that syntrophic hydrocarbon metabolism can also occur in the presence of electron acceptors. The elucidation of key features of syntrophic processes in defined co-cultures has benefited greatly from advances in 'omics' based tools. Such tools, along with approaches like stable isotope probing, are now being used to monitor carbon flow within an increasing number of hydrocarbon-degrading consortia to pinpoint the key microbial players involved in the degradative pathways. The metagenomic sequencing of hydrocarbon-utilizing consortia should help to further identify key syntrophic features and define microbial interactions in these complex communities. Copyright © 2013 Elsevier Ltd. All rights reserved.

Hydrocarbon market in El Salvador; Mercado de hidrocarburos en El Salvador

Energy Technology Data Exchange (ETDEWEB)

Nava de Hernandez, Gina Mercedes [Ministerio de Economia, Direccion de Energia, Minas e Hidrocarburos (El Salvador)

1997-07-01

This document presents a summary of the present situation of the market of hydrocarbons in El Salvador, doing a synthesis of the conformation of the industry, of the demand of the country, the prices and others. In addition, it shows the situation before and after the deregulation, making emphasis in the changes originated by such a measure. [Spanish] El presente documento presenta un resumen de la situacion actual del mercado de los hidrocarburos en El Salvador, haciendo una sintesis de la conformacion de la industria, de la demanda del pais, los precios y otros. Ademas muestra la situacion antes y despues de la desregulacion, haciendo enfasis en los cambios ocurridos por tal medida.

High-resolution gas chromatographic analysis of polycyclic aromatic hydrocarbons and aliphatic hydrocarbons

International Nuclear Information System (INIS)

Perez, M.; Gonzalez, D.

1988-01-01

A study of the analysis by gas chromatography of aromatic polycyclic hydrocarbons and aliphatic hydrocarbons is presented. The separation has been carried out by glass and fused silica capillary column in two different polar stationary phases OV-1 and SE-54. The limitation and the advantages of the procedure are discussed in terms of separation, sensitivity and precision. (Author) 20 refs

Hydrocarbon pollution from marinas in estuarine sediments

Science.gov (United States)

Voudrias, Evangelos A.; Smith, Craig L.

1986-03-01

A measure of the impact of marinas on three Eastern Virginia estuarine creeks was obtained by a study of hydrocarbons in their sediments. Two of the creeks support considerable marine activity, including pleasure boat marinas, boat repair facilities, and commercial fishing operations. The third creek, which served as a control, is seldom used by boats, and is surrounded by marsh and woodland. Sediments from the creeks with marinas contained significantly higher levels of both aromatic and aliphatic hydrocarbons than did the control. Differences in the concentrations of certain oil-pollution indicators, such as the 17α,21β-hopane homologs and phytane, and low molecular weight aromatic hydrocarbons, are indicative of light petroleum fractions. Most of the aromatic hydrocarbons from all creeks, however, appear to have a pyrogenic origin. Although hydrocarbons from three probable origins (petroleum, pyrogenesis, and recent biosynthesis) were detected in all locations, the petroleum-derived and pyrogenic hydrocarbons were of only minor importance relative to the biogenic hydrocarbons in the control creek.

Stable tetrabenzo-Chichibabin's hydrocarbons: Tunable ground state and unusual transition between their closed-shell and open-shell resonance forms

KAUST Repository

Zeng, Zebing; Sung, Youngmo; Bao, Nina; Tan, Davin; Lee, Richmond; Zafra, José Luis; Lee, Byungsun; Ishida, Masatoshi; Ding, Jun; Lõ pez Navarrete, Juan Teodomiro; Li, Yuan; Zeng, Wangdong; Kim, Dongho; Huang, Kuo-Wei; Webster, Richard D.; Casado, Juan; Wu, Jishan

2012-01-01

-shell PAH has been investigated for a long time. However, most of the studies are complicated by their inherent high reactivity. In this work, two new stable benzannulated Chichibabin's hydrocarbons 1-CS and 2-OS were prepared, and their electronic structure

BIOREMEDIATION OF A PETROLEUM-HYDROCARBON

African Journals Online (AJOL)

ES OBE

under field conditions in the bioremediation of a petroleum- hydrocarbon polluted ... an accelerated biodegradation of petroleum hydrocarbons in a polluted agricultural soil ..... 12) Jackson, M.L. Soil chemical analysis. ... biological assay. 3 rd.

Hydrothermal synthesis of sodium titanate nanotubes; Hydrotermalna synteza nanorurok titanatu sodneho

Energy Technology Data Exchange (ETDEWEB)

Miskoci, M.; Jesenak, K. [Univerzita Komenskeho, Prirodovedecka fakulta, Katedra anorganickej chemie, 84215 Bratislava (Slovakia); Caplovicova, M. [Univerzita Komenskeho, Prirodovedecka fakulta, Katedra loziskovej geologie, 84215 Bratislava (Slovakia)

2013-04-16

From suspension of nanoparticles TiO{sub 2} in concentrated water solution of NaOH were prepared by hydrothermal synthesis sodium titanates particles with different shapes. Influence of synthesis duration under temperature 180 grad C on the change of particles shapes was observed. The result of experiment showed that one day synthesis resulted to obtained product with high content of nanotubes, but the extension of this period led to the transformation of product's shape into stripes. From the results of experiment follows that as a precursor for TiO{sub 2} nanotubes preparation may be used only products of hydrothermal synthesis, which duration of pressure synthesis was not longer than 24 hours. (authors)

Aliphatic hydrocarbon and polycyclic aromatic hydrocarbon geochemistry of twelve major rivers in the Northwest Territories

International Nuclear Information System (INIS)

Backus, S.; Swyripa, M.; Peddle, J.; Jeffries, D.S.

1995-01-01

Suspended sediment and water samples collected from twelve major rivers in the Northwest Territories were analyzed for aliphatic hydrocarbons and polycyclic aromatic hydrocarbons (PAHs) to assess the sources and transport of hydrocarbons entering the Arctic Ocean. Three stations on the Mackenzie River and one station near the mouth of eleven other northern rivers were selected for sampling. Samples were collected on the Mackenzie River on four occasions to characterize spring, summer and fall flow conditions and once on the remaining eleven rivers during high flow conditions. The Mackenzie River is distinctively different then the other eleven rivers. Naturally occurring hydrocarbons predominate in the river. These hydrocarbons include biogenic alkanes, diagenic PAHs, petrogenic alkanes, and PAHs from oil seeps and/or bitumens. Anthropogenic inputs of PAHs are low as indicated by low concentrations of combustion PAHs. Alkyl PAH distributions indicate that a significant component of the lower molecular weight PAH fraction is petrogenic. The majority of the high molecular weight PAHs, together with the petrogenic PAHs have a principal source in the Mackenzie River

Development of miniature module for [11C] methionine synthesis

International Nuclear Information System (INIS)

Watanabe, Toshimitsu; Araya, Hiroshi; Ueno, Satoshi

2006-01-01

[ 18 F]FDG-PET has spread rapidly in the cancer diagnosis. On the other hand, [ 11 C]Methionine is paid attention as one of the PET drugs that may help cancer diagnosis by [ 18 F]FDG. Due to its short half-life, repeated preparations of [ 11 C] Methionine, two or three times a day, are generally required for the routine PET practice. Although the automatic synthesis devices for [ 11 C]Methionine were developed, it was difficult to supply [ 11 C]Methionine two times a day or more. We developed a methionine synthesis system that was able to supply [ 11 C]Methionine two times a day or more, and a new methionine synthesis unit. The new synthesis unit is able to synthesize [ 11 C]Methionine efficiently without HPLC preparation and evaporation in a short time. The new methionine synthesis unit and system are more useful for the routine synthesis of [ 11 C]Methionine. (author)

Synthesis of tritium-labeled fosfomycin

International Nuclear Information System (INIS)

Mertel, H.E.; Meriwether, H.T.

1982-01-01

Tritium gas was used as a labeling agent for the preparation of [1,2- 3 H]fosfomycin. Introduction of tritium into a precursor, the synthesis including resolution of the intermediate racemic 1,2-epoxypropylphosphonic acid, and preparation of both amine and calcium salts of the labeled antibiotic are described. (author)

Optrode for sensing hydrocarbons

Science.gov (United States)

Miller, H.; Milanovich, F.P.; Hirschfeld, T.B.; Miller, F.S.

1988-09-13

A two-phase system employing the Fujiwara reaction is provided for the fluorometric detection of halogenated hydrocarbons. A fiber optic is utilized to illuminate a column of pyridine trapped in a capillary tube coaxially attached at one end to the illuminating end of the fiber optic. A strongly alkaline condition necessary for the reaction is maintained by providing a reservoir of alkali in contact with the column of pyridine, the surface of contact being adjacent to the illuminating end of the fiber optic. A semipermeable membrane caps the other end of the capillary tube, the membrane being preferentially permeable to the halogenated hydrocarbon and but preferentially impermeable to water and pyridine. As the halogenated hydrocarbon diffuses through the membrane and into the column of pyridine, fluorescent reaction products are formed. Light propagated by the fiber optic from a light source, excites the fluorescent products. Light from the fluorescence emission is also collected by the same fiber optic and transmitted to a detector. The intensity of the fluorescence gives a measure of the concentration of the halogenated hydrocarbons. 5 figs.

Biodegradation of petroleum hydrocarbons in hypersaline environments

Directory of Open Access Journals (Sweden)

Luiz Fernando Martins

2012-09-01

Full Text Available Literature on hydrocarbon degradation in extreme hypersaline media presents studies that point to a negative effect of salinity increase on hydrocarbonoclastic activity, while several others report an opposite tendency. Based on information available in the literature, we present a discussion on the reasons that justify these contrary results. Despite the fact that microbial ability to metabolize hydrocarbons is found in extreme hypersaline media, indeed some factors are critical for the occurrence of hydrocarbon degradation in such environments. How these factors affect hydrocarbon degradation and their implications for the assessment of hydrocarbon biodegradation in hypersaline environments are presented in this review.

GOM Deepwater Horizon Oil Spill: A Time Series Analysis of Variations in Spilled Hydrocarbons

Science.gov (United States)

Palomo, C. M.; Yan, B.

2013-12-01

An estimated amount of 210 million gallons of crude oil was released into the Gulf of Mexico (GOM) from April 20th to July 15th 2010 during the Deepwater Horizon oil rig explosion. The spill caused a tremendous financial, ecological, environmental and health impact and continues to affect the GOM today. Variations in hydrocarbons including alkanes, hopanes and poly-cyclic aromatic hydrocarbons (PAHs) can be analyzed to better understand the oil spill and assist in oil source identification. Twenty-one sediment samples*, two tar ball samples and one surface water oil sample were obtained from distinct locations in the GOM and within varying time frames from May to December 2010. Each sample was extracted through the ASE 200 solvent extractor, concentrated down under nitrogen gas, purified through an alumina column, concentrated down again with nitrogen gas and analyzed via GC X GC-TOF MS. Forty-one different hydrocarbons were quantified in each sample. Various hydrocarbon 'fingerprints,' such as parental :alkylate PAH ratios, high molecular weight PAHs: low molecular weight alkane ratios, and carbon preference index were calculated. The initial objective of this project was to identify the relative hydrocarbon contributions of petrogenic sources and combustion sources. Based on the calculated ratios, it is evident that the sediment core taken in October of 2010 was greatly affected by combustion sources. Following the first month of the spill, oil in the gulf was burned in attempts to contain the spill. Combustion related sources have quicker sedimentation rates, and hydrocarbons from a combustion source essentially move into deeper depths quicker than those from a petrogenic source, as was observed in analyses of the October 2010 sediment. *Of the twenty-one sediment samples prepared, nine were quantified for this project.

Preparation of single phase molybdenum boride

International Nuclear Information System (INIS)

Camurlu, Hasan Erdem

2011-01-01

Highlights: → Formation of Mo and a mixture of molybdenum boride phases take place in preparation of molybdenum borides. → It is intricate to prepare single phase molybdenum borides. → Formation of single phase MoB from MoO 3 + B 2 O 3 + Mg mixtures has not been reported previously. → Single phase MoB was successfully prepared through a combination of mechanochemical synthesis and annealing process. - Abstract: The formation of MoB through volume combustion synthesis (VCS), and through mechanochemical synthesis (MCS) followed by annealing has been investigated. MoO 3 , B 2 O 3 and Mg were used as reactants while MgO and NaCl were introduced as diluents. Products were leached in dilute HCl solution and were subjected to X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM) examinations. Mo was the major phase component in the VCS products under all the experimental conditions. Mo 2 B, MoB, MoB 2 and Mo 2 B 5 were found as minor phases. Products of MCS contained a mixture of Mo 2 B, MoB, MoB 2 and Mo. After annealing the MCS product at 1400 deg. C for 3 h, single phase α-MoB was obtained.

Influence of synthesis experimental parameters on the formation of nanoparticles of magnetite prepared by thermal decomposition method

International Nuclear Information System (INIS)

Vega, Jaime; Picasso, Gino; Lopez, Alcides; Aviles Felix, Luis

2013-01-01

In this work, nanoparticles based on magnetite have been synthesized by thermal decomposition via solvent-controlled synthesis in polyols, using triethylene glycol (TREG). The starting precursor were solutions of nitrate and acetylacetonate of Fe. The samples have been characterized by X-ray diffraction technique (XRD), adsorption-desorption of N 2 (BET equation model), scanning electronic microscopy (SEM), thermogravimetric analysis (TGA), vibration sample magnetometry (VSM) and Moessbauer spectroscopy. XRD diffractogram revealed the majority presence of spinel-like structural phases of magnetite in all samples. SEM micrographs showed morphological differences; the samples prepared from acetylacetonate presented good dispersion of particles whereas the ones prepared from nitrate-small agglomerations. BET isotherms of samples depicted a mesoporous profile which corresponded to IV type. TGA thermogram showed two defined regions which corresponded to vaporization of polyol light fractions and TREG. Zero coercivity on the magnetization curve of acetylacetonate precursor samples have been observed by VSM, which indicates superparamagnetic behavior. Moessbauer spectra of samples detected the presence of 4 doublet-like subspectra due to the presence of 4 sites occupied by Fe in paramagnetic or superparamagnetic state. (author)

Noble gas and hydrocarbon tracers in multiphase unconventional hydrocarbon systems: Toward integrated advanced reservoir simulators

Science.gov (United States)

Darrah, T.; Moortgat, J.; Poreda, R. J.; Muehlenbachs, K.; Whyte, C. J.

2015-12-01

Although hydrocarbon production from unconventional energy resources has increased dramatically in the last decade, total unconventional oil and gas recovery from black shales is still less than 25% and 9% of the totals in place, respectively. Further, the majority of increased hydrocarbon production results from increasing the lengths of laterals, the number of hydraulic fracturing stages, and the volume of consumptive water usage. These strategies all reduce the economic efficiency of hydrocarbon extraction. The poor recovery statistics result from an insufficient understanding of some of the key physical processes in complex, organic-rich, low porosity formations (e.g., phase behavior, fluid-rock interactions, and flow mechanisms at nano-scale confinement and the role of natural fractures and faults as conduits for flow). Noble gases and other hydrocarbon tracers are capably of recording subsurface fluid-rock interactions on a variety of geological scales (micro-, meso-, to macro-scale) and provide analogs for the movement of hydrocarbons in the subsurface. As such geochemical data enrich the input for the numerical modeling of multi-phase (e.g., oil, gas, and brine) fluid flow in highly heterogeneous, low permeability formations Herein we will present a combination of noble gas (He, Ne, Ar, Kr, and Xe abundances and isotope ratios) and molecular and isotopic hydrocarbon data from a geographically and geologically diverse set of unconventional hydrocarbon reservoirs in North America. Specifically, we will include data from the Marcellus, Utica, Barnett, Eagle Ford, formations and the Illinois basin. Our presentation will include geochemical and geological interpretation and our perspective on the first steps toward building an advanced reservoir simulator for tracer transport in multicomponent multiphase compositional flow (presented separately, in Moortgat et al., 2015).

Synthesis and electrochemical analysis of AlVMoO7 oxide prepared ...

Indian Academy of Sciences (India)

2018-05-16

May 16, 2018 ... solid solution and two-phase regimes. In the voltage ... LiMn2O4) [1]. Among these compounds, olivine LiFePO4, ... polyanions provide numerous metal oxidation states, struc- tural stability ... 2.1a Sol–gel synthesis (SG): In SG synthesis method, ... AlVMoO7 and confirms that only a single phase is formed.

Preparation of carbon-14-labelled gallic acid

International Nuclear Information System (INIS)

Kozak, I.; Prochazka, M.

1977-01-01

Gallic acid labelled with 14 C was prepared for the needs of biological studies. A lithium derivative of trimethoxybenzene was treated with 14 CO 2 and then demethylated to yeld [carboxyl- 14 C]gallic acid. The preparation scheme and the individual steps of the synthesis are described in detail

Direct Synthesis of Co-doped Graphene on Dielectric Substrates Using Solid Carbon Sources

Institute of Scientific and Technical Information of China (English)

Qi Wang; Pingping Zhang; Qiqi Zhuo; Xiaoxin Lv; Jiwei Wang; Xuhui Sun

2015-01-01

Direct synthesis of high-quality doped graphene on dielectric substrates without transfer is highly desired for simplified device processing in electronic applications.However,graphene synthesis directly on substrates suitable for device applications,though highly demanded,remains unattainable and challenging.Here,a simple and transfer-free synthesis of high-quality doped graphene on the dielectric substrate has been developed using a thin Cu layer as the top catalyst and polycyclic aromatic hydrocarbons as both carbon precursors and doping sources.N-doped and N,F-co-doped graphene have been achieved using TPB and F16Cu Pc as solid carbon sources,respectively.The growth conditions were systematically optimized and the as-grown doped graphene were well characterized.The growth strategy provides a controllable transfer-free route for high-quality doped graphene synthesis,which will facilitate the practical applications of graphene.

Process for separating liquid hydrocarbons from waxes

Energy Technology Data Exchange (ETDEWEB)

Sowa, F J

1948-03-08

A process is described for the separation of liquid hydrocarbons from waxes comprising adding to a mixture of liquid hydrocarbons and waxes a sufficient quantity of an organo-silicon compound to cause the separation of the hydrocarbon and wax. The organo-silicon compounds are selected from the class of organic silicanes and their hydrolysis products and polymers. The silicanes have the formula R/sub y/SiX/sub z/, in which R is a saturated or unsaturated hydrocarbon radical, X is a halogen or another hydrocarbon radical or an -OR group, y has a value 1, 2, or 3 and z has a value 1, 2, or 3.

Process for treating hydrocarbons, etc

Energy Technology Data Exchange (ETDEWEB)

1933-09-15

A process is described for treating simultaneously bituminous substances and hydrocarbon oils for the production of low-boiling hydrocarbons and volatilization of the bituminous substances, characterized by the fact that it consists of heating a current of charge constituted by a mixture of the bituminous substances and hydrocarbon oils, to a high temperature, passing the heated current into a zone of extended reaction where the vapors are separated from the liquid or solid residue to favor transformation of the liquid hydrocarbons and volatilization of the bituminous substances, owing to the utilization of a heating agent carried to a high temperature being brought in contact with the heated charge in order to communicate its heat to the charge, while this later presents itself as relatively fine pellet or in the condition of distinct particles, particularly separated from one another.

Tailoring gas-phase CO2 electroreduction selectivity to hydrocarbons at Cu nanoparticles

Science.gov (United States)

Merino-Garcia, I.; Albo, J.; Irabien, A.

2018-01-01

Copper-based surfaces appear as the most active catalysts for CO2 electroreduction to hydrocarbons, even though formation rates and efficiencies still need to be improved. The aim of the present work is to evaluate the continuous gas-phase CO2 electroreduction to hydrocarbons (i.e. ethylene and methane) at copper nanoparticulated-based surfaces, paying attention to particle size influence (ranging from 25-80 nm) on reaction productivity, selectivity, and Faraday efficiency (FE) for CO2 conversion. The effect of the current density and the presence of a microporous layer within the working electrode are then evaluated. Copper-based gas diffusion electrodes are prepared by airbrushing the catalytic ink onto carbon supports, which are then coupled to a cation exchange membrane (Nafion) in a membrane electrode assembly. The results show that the use of smaller copper nanoparticles (25 nm) leads to a higher ethylene production (1148 μmol m-2 s-1) with a remarkable high FE (92.8%), at the same time, diminishing the competitive hydrogen evolution reaction in terms of FE. This work demonstrates the importance of nanoparticle size on reaction selectivity, which may be of help to design enhanced electrocatalytic materials for CO2 valorization to hydrocarbons.

Supercritical fluid synthesis inthe preparation of β+-emitting labelled compounds

International Nuclear Information System (INIS)

Jacobson, G.; Markides, K.E.; Laangstroem, B.

1994-01-01

A system for synthesis in supercritical fluids has been developed for the microscale synthesis of pharmaceuticals labelled with 11 C. Supercritical ammonia was selected as the reaction medium and the following variables were studied in detail: trapping efficiency, cell design, substrate concentration, operation design, and temperature and pressure conditions. Alkylation of phenol by [ 11 C]methyl iodide to yield [methyl- 11 C]anisole was used as a model reaction for evaluation of the system. The results show an increased radiochemical yield in the highly compressible near-critical region. (au) (40 refs.)

Fate and degradation of petroleum hydrocarbons in stormwater bioretention cells

Science.gov (United States)

LeFevre, Gregory Hallett

This dissertation describes the investigation of the fate of hydrocarbons in stormwater bioretention areas and those mechanisms that affect hydrocarbon fate in such systems. Seventy-five samples from 58 bioretention areas were collected and analyzed to measure total petroleum hydrocarbon (TPH) residual and biodegradation functional genes. TPH residual in bioretention areas was greater than background sites but low overall (hydrocarbon biodegradation. Field soils were capable of mineralizing naphthalene, a polycyclic aromatic hydrocarbon (PAH) when incubated in the laboratory. In an additional laboratory investigation, a column study was initiated to comprehensively determine naphthalene fate in a simulated bioretention cell using a 14C-labeled tracer. Sorption to soil was the greatest sink of naphthalene in the columns, although biodegradation and vegetative uptake were also important loss mechanisms. Little leaching occurred following the first flush, and volatilization was insignificant. Significant enrichment of naphthalene degrading bacteria occurred over the course of the experiment as a result of naphthalene exposure. This was evident from enhanced naphthalene biodegradation kinetics (measured via batch tests), significant increases in naphthalene dioxygenase gene quantities, and a significant correlation observed between naphthalene residual and biodegradation functional genes. Vegetated columns outperformed the unplanted control column in terms of total naphthalene removal and biodegradation kinetics. As a result of these experiments, a final study focused on why planted systems outperform unplanted systems was conducted. Plant root exudates were harvested from hydroponic setups for three types of plants. Additionally, a solution of artificial root exudates (AREs) as prepared. Exudates were digested using soil bacteria to create metabolized exudates. Raw and metabolized exudates were characterized for dissolved organic carbon, specific UV absorbance

Sustainable hydrocarbon fuels by recycling CO2 and H2O with renewable or nuclear energy

DEFF Research Database (Denmark)

Graves, Christopher R.; Ebbesen, Sune; Mogensen, Mogens Bjerg

2011-01-01

) and biofuels have received the most attention, similar hydrocarbons can be produced without using fossil fuels or biomass. Using renewable and/or nuclear energy, carbon dioxide and water can be recycled into liquid hydrocarbon fuels in non-biological processes which remove oxygen from CO2 and H2O (the reverse...... of fuel combustion). Capture of CO2 from the atmosphere would enable a closed-loop carbon-neutral fuel cycle. This article critically reviews the many possible technological pathways for recycling CO2 into fuels using renewable or nuclear energy, considering three stages—CO2 capture, H2O and CO2...... by Fischer–Tropsch synthesis is identified as one of the most promising, feasible routes. An analysis of the energy balance and economics of this CO2 recycling process is presented. We estimate that the full system can feasibly operate at 70% electricity-to-liquid fuel efficiency (higher heating value basis...

Solution Combustion Preparation Of Nano-Al2O3: Synthesis and Characterization

Directory of Open Access Journals (Sweden)

M. Farahmandjou

2015-06-01

Full Text Available The aluminum oxide materials are widely used in ceramics, refractories and abrasives due to their hardness, chemical inertness, high melting point, non-volatility and resistance to oxidation and corrosion. The paper describes work done on synthesis of α-alumina by using the simple, non-expensive solution combustion method using glycine as fuel.Aluminum oxide (Al2O3 nanoparticles were synthesized by aluminum nitrate 9-hydrate as precursor and glycine as fuel. The samples were characterized by high resolution transmission electron microscopy (HRTEM, field effect scanning electron microscopy (FESEM, X-ray diffraction (XRD and electron dispersive spectroscopy (EDS. As there are many forms of transition aluminas produced during this process, x-ray diffraction (XRD technique was used to identify α-alumina. The diameter of sphere-like as-prepared nanoparticles was about 10 nm as estimated by XRD technique and direct HRTEM observation. The surface morphological studies from SEM depicted the size of alumina decreases with increasing annealing temperature. Absorbance peak of UV-Vis spectrum showed the small bandgap energy of 2.65 ev and the bandgap energy increased with increasing annealing temperature because of reducing the size.

Nanoscale intimacy in bifunctional catalysts for selective conversion of hydrocarbons

Science.gov (United States)

Zecevic, Jovana; Vanbutsele, Gina; de Jong, Krijn P.; Martens, Johan A.

2015-12-01

The ability to control nanoscale features precisely is increasingly being exploited to develop and improve monofunctional catalysts. Striking effects might also be expected in the case of bifunctional catalysts, which are important in the hydrocracking of fossil and renewable hydrocarbon sources to provide high-quality diesel fuel. Such bifunctional hydrocracking catalysts contain metal sites and acid sites, and for more than 50 years the so-called intimacy criterion has dictated the maximum distance between the two types of site, beyond which catalytic activity decreases. A lack of synthesis and material-characterization methods with nanometre precision has long prevented in-depth exploration of the intimacy criterion, which has often been interpreted simply as ‘the closer the better’ for positioning metal and acid sites. Here we show for a bifunctional catalyst—comprising an intimate mixture of zeolite Y and alumina binder, and with platinum metal controllably deposited on either the zeolite or the binder—that closest proximity between metal and zeolite acid sites can be detrimental. Specifically, the selectivity when cracking large hydrocarbon feedstock molecules for high-quality diesel production is optimized with the catalyst that contains platinum on the binder, that is, with a nanoscale rather than closest intimacy of the metal and acid sites. Thus, cracking of the large and complex hydrocarbon molecules that are typically derived from alternative sources, such as gas-to-liquid technology, vegetable oil or algal oil, should benefit especially from bifunctional catalysts that avoid locating platinum on the zeolite (the traditionally assumed optimal location). More generally, we anticipate that the ability demonstrated here to spatially organize different active sites at the nanoscale will benefit the further development and optimization of the emerging generation of multifunctional catalysts.

Applications of density functional theory calculations to selected problems in hydrocarbon processing

Science.gov (United States)

Nabar, Rahul

Recent advances in theoretical techniques and computational hardware have made it possible to apply Density Functional Theory (DFT) methods to realistic problems in heterogeneous catalysis. Hydrocarbon processing is economically, and strategically, a very important industrial sector in today's world. In this thesis, we employ DFT methods to examine several important problems in hydrocarbon processing. Fischer Tropsch Synthesis (FTS) is a mature technology to convert synthesis gas derived from coal, natural-gas or biomass into liquid fuels, specifically diesel. Iron is an active FTS catalyst, but the absence of detailed reaction mechanisms make it difficult to maximize activity and optimize product distribution. We evaluate thermochemistry, kinetics and Rate Determining Steps (RDS) for Fischer Tropsch Synthesis on several models of Fe catalysts: Fe(110), Fe(211) and Pt promoted Fe(110). Our studies indicated that CO-dissociation is likely to be the RDS under most reaction conditions, but the DFT-calculated activation energy ( Ea) for direct CO dissociation was too large to explain the observed catalyst activity. Consequently we demonstrate that H-assisted CO-dissociation pathways are competitive with direct CO dissociation on both Co and Fe catalysts and could be responsible for a major fraction of the reaction flux (especially at high CO coverages). We then extend this alternative mechanistic model to closed-packed facets of nine transition metal catalysts (Fe, Co, Ni, Ru, Rh, Pd, Os, Ir and Pt). H-assisted CO dissociation offers a kinetically easier route on each of the metals studied. DFT methods are also applied to another problem from the petroleum industry: discovery of poison-resistant, bimetallic, alloy catalysts (poisons: C, S, CI, P). Our systematic screening studies identify several Near Surface Alloys (NSAs) that are expected to be highly poison-resistant yet stable and avoiding adsorbate induced reconstruction. Adsorption trends are also correlated with

Selection and evaluation of technologies for oil rim preparation of Zapolyarnoye oilfield

Science.gov (United States)

Vazhenina, L. V.

2017-10-01

The article deals with various technologies for the oil rims preparation of Zapolyarnoye oil and gas condensate field. The following circuits were considered for the selection of the technology of preparation of extracted fluid: low-temperature separation (STC); low-temperature condensation (LTC); a low-temperature rectification (NTR); low-temperature absorption (LTA); membrane technology (Mt). Diagrams of these processes were collected and tested in the system HYSYS process simulation. Efficiency analysis of hydrocarbon raw materials preparation on the basis of functions, selection of components and narrow fractions.

Platinum-Niobium(V Oxide/Carbon Nanocomposites Prepared By Microwave Synthesis For Ethanol Oxidation

Directory of Open Access Journals (Sweden)

Virginija KEPENIENĖ

2016-05-01

Full Text Available In the present work, Pt nanoparticles were deposited by means of microwave synthesis on the primary carbon supported Nb2O5 composite which was prepared in two different ways: (A by dispersion of Nb2O5 and carbon with the mass ratio equal to 1:1 in a 2-propanol solution by ultrasonication for 30 min. with further desiccation of the mixture and (B by heating the Nb2O5/C composite obtained according to the procedure (A at 500 °C for 2 h. The transmission electron microscopy was used to determine the shape and the size of catalyst particles. X-ray diffraction and inductively coupled plasma optical emission spectroscopy were employed to characterize the structure and composition of the synthesized catalysts. The electrocatalytic activity of the synthesized catalysts towards the oxidation of ethanol in an alkaline medium was investigated by means of cyclic voltammetry.DOI: http://dx.doi.org/10.5755/j01.ms.22.2.8609

Breaking the Fischer–Tropsch synthesis selectivity : Direct conversion of syngas to gasoline over hierarchical Co/H-ZSM-5 catalysts

NARCIS (Netherlands)

Sartipi, S.; Parashar, K.; Makkee, M.; Gascon, J.; Kapteijn, F.

2012-01-01

We report the combination of Fischer–Tropsch catalyst with acid functionality in one single catalyst particle. The resulting bifunctional catalyst is capable of producing gasoline range hydrocarbons from synthesis gas in one catalytic step with outstanding activities and selectivities.

Gamma-radiation induced polymerization of methyl methacrylate in aliphatic hydrocarbons: kinetics and evidence for incorporation of hydrocarbon in the polymer chain

International Nuclear Information System (INIS)

Mohan, H.; Iyer, R.M.

1989-01-01

On γ-radiolysis, the rate of polymerization of methyl methacrylate in hydrocarbon solvents is observed to decrease. It is explained by hydrocarbon entry into the polymer chains. The hydrocarbon entry into the polymer chains is observed to take place at later stages of polymerization and increases with hydrocarbon chain length. The extent of hydrocarbon entry into the polymer chains is estimated by NMR and GLC analysis. It is observed to be equal to ∼ 12% corresponding to ∼ 97 hexadecane molecules in each polymer chain. The IR, DSC, MW determination and radiation effects on the polymer showed evidences for hydrocarbon entry into the polymer. It is explained by chain transfer from the growing polymer radical to the hydrocarbon molecules. The chain transfer constant is determined to be equal to 1 x 10 -2 . (author)

Steam hydrocarbon cracking and reforming

NARCIS (Netherlands)

Golombok, M.

2004-01-01

Many industrial chemical processes are taught as distinct contrasting reactions when in fact the unifying comparisons are greater than the contrasts. We examine steam hydrocarbon reforming and steam hydrocarbon cracking as an example of two processes that operate under different chemical reactivity

Laser-assisted chemical vapor deposition setup for fast synthesis of graphene patterns

Science.gov (United States)

Zhang, Chentao; Zhang, Jianhuan; Lin, Kun; Huang, Yuanqing

2017-05-01

An automatic setup based on the laser-assisted chemical vapor deposition method has been developed for the rapid synthesis of graphene patterns. The key components of this setup include a laser beam control and focusing unit, a laser spot monitoring unit, and a vacuum and flow control unit. A laser beam with precision control of laser power is focused on the surface of a nickel foil substrate by the laser beam control and focusing unit for localized heating. A rapid heating and cooling process at the localized region is induced by the relative movement between the focalized laser spot and the nickel foil substrate, which causes the decomposing of gaseous hydrocarbon and the out-diffusing of excess carbon atoms to form graphene patterns on the laser scanning path. All the fabrication parameters that affect the quality and number of graphene layers, such as laser power, laser spot size, laser scanning speed, pressure of vacuum chamber, and flow rates of gases, can be precisely controlled and monitored during the preparation of graphene patterns. A simulation of temperature distribution was carried out via the finite element method, providing a scientific guidance for the regulation of temperature distribution during experiments. A multi-layer graphene ribbon with few defects was synthesized to verify its performance of the rapid growth of high-quality graphene patterns. Furthermore, this setup has potential applications in other laser-based graphene synthesis and processing.

Synthesis of 6-Methyl-9-propyldibenzothiophene-4-ol

Energy Technology Data Exchange (ETDEWEB)

Eisenbraun, E.J.

1991-02-15

The synthesis route for preparing the title compound, has been carried out on a small scale for the preparation of a mixture of isomers. Alternative routes for the cyclization are being explored. (DLC)

Russia and China hydrocarbon relations. A building block toward international hydrocarbon regulation?

International Nuclear Information System (INIS)

Locatelli, Catherine; Abbas, Mehdi; Rossiaud, Sylvain

2015-12-01

This article is a first step of a research agenda on international hydrocarbon regulations. With regards to both: i) the new wealth and power equilibrium in the international political economy and ii) the new political economy of carbon that is emerging from The Paris agreement on Climate changes, this research agenda aims at analysing the changing national structures of governance and the ways these changes lead to international, bilateral, pluri-lateral or multilateral hydrocarbon regulation

GC of catalytic reactions products involved in the promising fuel synthesis

Energy Technology Data Exchange (ETDEWEB)

Zheivot, V.; Sazonova, N. [Russian Academy of Sciences, Novosibirsk (Russian Federation). Boreskov Inst. of Catalysis

2012-09-15

Catalytic reactions involved in the synthesis of the promising kinds of novel fuel and products formed in these reactions were systematized according to the resulting fuel type. Generalization of the retention of the substances comprising these products is presented. Chromatograms exhibiting their separation on chromatographic materials with the surface of different chemical properties are summarized. We propose procedures for gas-chromatographic analysis of the catalytic reactions products formed in the synthesis of hydrogen, methanol, dimethyl ether and hydrocarbons as a new generation of fuel alternative to petroleum and coal. For partial oxidation of methane into synthesis gas, on-line determination of the components obtained in the reaction was carried out by gas chromatography and gas analyzer based on different physicochemical methods (IR spectroscopy and electrochemical methods). Similarity of the results obtained using these methods is demonstrated. (orig.)

27 CFR 21.125 - Rubber hydrocarbon solvent.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Rubber hydrocarbon solvent. 21.125 Section 21.125 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU....125 Rubber hydrocarbon solvent. (a) Rubber hydrocarbon solvent is a petroleum derivative. (b...

Collision data involving hydro-carbon molecules

International Nuclear Information System (INIS)

Tawara, H.; Itikawa, Y.; Nishimura, H.; Tanaka, H.; Nakamura, Y.

1990-07-01

Hydro-carbon molecules are abundantly produced when graphites are used as internal wall materials of hydrogen plasmas and strongly influence properties of low temperature plasmas near the edges as well as those of high temperature plasmas at the center. In this report, following simple description of the production mechanisms of hydro-carbon molecules under the interactions between graphite and hydrogen plasma, the present status of collision data for hydro-carbon molecules by electron impact is discussed and the relevant data are summarized in a series of figures and tables. It should also be noted that, in addition to fusion plasmas, these hydrocarbon data compiled here are quite useful in other applications such as plasma chemistry and material processing. (author)

Synthesis of Thin Film Composite Metal-Organic Frameworks Membranes on Polymer Supports

KAUST Repository

Barankova, Eva

2017-06-01

Since the discovery of size-selective metal-organic frameworks (MOF) researchers have tried to manufacture them into gas separation membranes. ZIF-8 became the most studied MOF for membrane applications mainly because of its simple synthesis, good chemical and thermal stability, recent commercial availability and attractive pore size. The aim of this work is to develop convenient methods for growing ZIF thin layers on polymer supports to obtain defect-free ZIF membranes with good gas separation properties. We present new approaches for ZIF membranes preparation on polymers. We introduce zinc oxide nanoparticles in the support as a secondary metal source for ZIF-8 growth. Initially the ZnO particles were incorporated into the polymer matrix and later on the surface of the polymer by magnetron sputtering. In both cases, the ZnO facilitated to create more nucleation opportunities and improved the ZIF-8 growth compared to the synthesis without using ZnO. By employing the secondary seeded growth method, we were able to obtain thin (900 nm) ZIF-8 layer with good gas separation performance. Next, we propose a metal-chelating polymer as a suitable support for growing ZIF layers. Defect-free ZIF-8 films with a thickness of 600 nm could be obtained by a contra-diffusion method. ZIF-8 membranes were tested for permeation of hydrogen and hydrocarbons, and one of the highest selectivities reported so far for hydrogen/propane, and propylene/propane was obtained. Another promising method to facilitate the growth of MOFs on polymeric supports is the chemical functionalization of the support surface with functional groups, which can complex metal ions and which can covalently bond the MOF crystals. We functionalized the surface of a common porous polymeric membrane with amine groups, which took part in the reaction to form ZIF-8 nanocrystals. We observed an enhancement in adhesion between the ZIF layer and the support. The effect of parameters of the contra-diffusion experiment

Carbon nanotubes/magnetite hybrids prepared by a facile synthesis process and their magnetic properties

International Nuclear Information System (INIS)

Zhang Li; Ni, Qing-Qing; Natsuki, Toshiaki; Fu Yaqin

2009-01-01

In this paper, a facile synthesis process is proposed to prepare multiwalled carbon nanotubes/magnetite (MWCNTs/Fe 3 O 4 ) hybrids. The process involves two steps: (1) water-soluble CNTs are synthesized by one-pot modification using potassium persulfate (KPS) as oxidant. (2) Fe 3 O 4 is assembled along the treated CNTs by employing a facile hydrothermal process with the presence of hydrazine hydrate as the mineralizer. The treated CNTs can be easily dispersed in aqueous solvent. Moreover, X-ray photoelectron spectroscopy (XPS) analysis reveals that several functional groups such as potassium carboxylate (-COOK), carbonyl (-C=O) and hydroxyl (-C-OH) groups are formed on the nanotube surfaces. The MWCNTs/Fe 3 O 4 hybrids are characterized with respect to crystal structure, morphology, element composition and magnetic property by X-ray diffraction (XRD), transmission electron microscopy (TEM), XPS and superconducting quantum interference device (SQUID) magnetometer. XRD and TEM results show that the Fe 3 O 4 nanoparticles with diameter in the range of 20-60 nm were firmly assembled on the nanotube surface. The magnetic property investigation indicated that the CNTs/Fe 3 O 4 hybrids exhibit a ferromagnetic behavior and possess a saturation magnetization of 32.2 emu/g. Further investigation indicates that the size of assembled Fe 3 O 4 nanoparticles can be turned by varying experiment factors. Moreover, a probable growth mechanism for the preparation of CNTs/Fe 3 O 4 hybrids was discussed.

PRACTICAL PREPARATION OF RESVERATROL 3-O-β-D-GLUCURONIDE

OpenAIRE

Jungong, Christian S.; Novikov, Alexei V.

2012-01-01

A practical synthesis of resveratrol 3-O-β-D-glucuronide, suitable for preparation of large quantities, was developed using selective deacetylation of resveratrol triacetate with ammonium acetate. A simplified procedure for large scale preparation of resveratrol is also reported.

Process for desulfurizing hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

1937-04-12

A process is described for the desulfurization of a mixture of hydrocarbons, and in particular hydrocarbons containing less than 7 atoms of carbon and sulfur compounds of the type of sulfur carbonyl, characterized by the fact that the mixture, preferably in the liquid phase, is brought in contact with a solution of caustic alkali, essentially anhydrous or preferably with a solution of alkali hydroxide in an organic hydroxy nonacid solvent, for example, an alcohol, or with an alkaline alcoholate, under conditions suitable to the formation of hydrogen sulfide which produces a hydrocarbon mixture free from sulfur compounds of the sulfur carbonyl type but containing hydrogen sulfide, and that it is treated, following mixing, having beem submitted to the first treatment, by means of aqueous alkaline hydroxide to eliminate the hydrogen sulfide.

Hydrocarbon-degrading bacteria isolation and surfactant influence ...

African Journals Online (AJOL)

Hydrocarbons are substantially insoluble in water, often remaining partitioned in the non-aqueous phase liquid (NAPL). However, there had been little or no attempts to advance the bioavailability of hydrocarbons through the use of surfactants. This study was conducted based on the need to isolate hydrocarbon degrading ...

Sensitivity ranking for freshwater invertebrates towards hydrocarbon contaminants.

Science.gov (United States)

Gerner, Nadine V; Cailleaud, Kevin; Bassères, Anne; Liess, Matthias; Beketov, Mikhail A

2017-11-01

Hydrocarbons have an utmost economical importance but may also cause substantial ecological impacts due to accidents or inadequate transportation and use. Currently, freshwater biomonitoring methods lack an indicator that can unequivocally reflect the impacts caused by hydrocarbons while being independent from effects of other stressors. The aim of the present study was to develop a sensitivity ranking for freshwater invertebrates towards hydrocarbon contaminants, which can be used in hydrocarbon-specific bioindicators. We employed the Relative Sensitivity method and developed the sensitivity ranking S hydrocarbons based on literature ecotoxicological data supplemented with rapid and mesocosm test results. A first validation of the sensitivity ranking based on an earlier field study has been conducted and revealed the S hydrocarbons ranking to be promising for application in sensitivity based indicators. Thus, the first results indicate that the ranking can serve as the core component of future hydrocarbon-specific and sensitivity trait based bioindicators.

Catalytic autothermal reforming of hydrocarbon fuels for fuel cells

International Nuclear Information System (INIS)

Krumpelt, M.; Krause, T.; Kopasz, J.; Carter, D.; Ahmed, S.

2002-01-01

Fuel cell development has seen remarkable progress in the past decade because of an increasing need to improve energy efficiency as well as to address concerns about the environmental consequences of using fossil fuel for producing electricity and for propulsion of vehicles[1]. The lack of an infrastructure for producing and distributing H(sub 2) has led to a research effort to develop on-board fuel processing technology for reforming hydrocarbon fuels to generate H(sub 2)[2]. The primary focus is on reforming gasoline, because a production and distribution infrastructure for gasoline already exists to supply internal combustion engines[3]. Existing reforming technology for the production of H(sub 2) from hydrocarbon feedstocks used in large-scale manufacturing processes, such as ammonia synthesis, is cost prohibitive when scaled down to the size of the fuel processor required for transportation applications (50-80 kWe) nor is it designed to meet the varying power demands and frequent shutoffs and restarts that will be experienced during normal drive cycles. To meet the performance targets required of a fuel processor for transportation applications will require new reforming reactor technology developed to meet the volume, weight, cost, and operational characteristics for transportation applications and the development of new reforming catalysts that exhibit a higher activity and better thermal and mechanical stability than reforming catalysts currently used in the production of H(sub 2) for large-scale manufacturing processes

Solution-chemical route to generalized synthesis of metal germanate nanowires with room-temperature, light-driven hydrogenation activity of CO2 into renewable hydrocarbon fuels.

Science.gov (United States)

Liu, Qi; Zhou, Yong; Tu, Wenguang; Yan, Shicheng; Zou, Zhigang

2014-01-06

A facile solution-chemical route was developed for the generalized preparation of a family of highly uniform metal germanate nanowires on a large scale. This route is based on the use of hydrazine monohydrate/H2O as a mixed solvent under solvothermal conditions. Hydrazine has multiple effects on the generation of the nanowires: as an alkali solvent, a coordination agent, and crystal anisotropic growth director. Different-percentage cobalt-doped Cd2Ge2O6 nanowires were also successfully obtained through the addition of Co(OAc)2·4H2O to the initial reaction mixture for future investigation of the magnetic properties of these nanowires. The considerably negative conduction band level of the Cd2Ge2O6 nanowire offers a high driving force for photogenerated electron transfer to CO2 under UV-vis illumination, which facilitates CO2 photocatalytic reduction to a renewable hydrocarbon fuel in the presence of water vapor at room temperature.

High Pressure Preignition Chemistry of Hydrocarbons and Hydrocarbon Mixtures

National Research Council Canada - National Science Library

Cernansky, N.P

1998-01-01

.... The research program entailed mechanistic studies examining the oxidation chemistry of single-component hydrocarbons and ignition studies examining the overall ignition of pure single component fuels and fuel blends...

KINETICS OF SLURRY PHASE FISCHER-TROPSCH SYNTHESIS. FOURTH ANNUAL TECHNICAL PROGRESS REPORT

International Nuclear Information System (INIS)

Bukur, Dragomir B.; Froment, Gilbert F.; Olewski, Tomasz

2006-01-01

This report covers the fourth year of a research project conducted under the University Coal Research Program. The overall objective of this project is to develop a comprehensive kinetic model for slurry-phase Fischer-Tropsch synthesis (FTS) employing iron-based catalysts. This model will be validated with experimental data obtained in a stirred-tank slurry reactor (STSR) over a wide range of process conditions. The model will be able to predict molar flow rates and concentrations of all reactants and major product species (water, carbon dioxide, linear 1- and 2-olefins, and linear paraffins) as a function of reaction conditions in the STSR. During the fourth year of the project, an analysis of experimental data collected during the second year of this project was performed. Kinetic parameters were estimated utilizing product distributions from 27 mass balances. During the reporting period two kinetic models were employed: a comprehensive kinetic model of Dr. Li and co-workers (Yang et al., 2003) and a hydrocarbon selectivity model of Van der Laan and Beenackers (1998, 1999) The kinetic model of Yang et al. (2003) has 24 parameters (20 parameters for hydrocarbon formation, and 4 parameters for the water-gas-shift (WGS) reaction). Kinetic parameters for the WGS reaction and FTS synthesis were estimated first separately, and then simultaneously. The estimation of these kinetic parameters employed the Levenberg-Marquardt (LM) method and the trust-region reflective Newton large-scale (LS) method. A genetic algorithm (GA) was incorporated into estimation of parameters for FTS reaction to provide initial estimates of model parameters. All reaction rate constants and activation energies were found to be positive, but at the 95% confidence level the intervals were large. Agreement between predicted and experimental reaction rates has been fair to good. Light hydrocarbons are predicted fairly accurately, whereas the model underpredicts values of higher molecular weight

A Laboratory Preparation of Aspartame Analogs Using Simultaneous Multiple Parallel Synthesis Methodology

Science.gov (United States)

Qvit, Nir; Barda, Yaniv; Gilon, Chaim; Shalev, Deborah E.

2007-01-01

This laboratory experiment provides a unique opportunity for students to synthesize three analogues of aspartame, a commonly used artificial sweetener. The students are introduced to the powerful and useful method of parallel synthesis while synthesizing three dipeptides in parallel using solid-phase peptide synthesis (SPPS) and simultaneous…

Process for refining hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Risenfeld, E H

1924-11-26

A process is disclosed for the refining of hydrocarbons or other mixtures through treatment in vapor form with metal catalysts, characterized by such metals being used as catalysts, which are obtained by reduction of the oxide of minerals containing the iron group, and by the vapors of the hydrocarbons, in the presence of the water vapor, being led over these catalysts at temperatures from 200 to 300/sup 0/C.

Combustion Synthesis Of Ultralow-density Nanoporous Gold Foams

Energy Technology Data Exchange (ETDEWEB)

Tappan, Bruce C [Los Alamos National Laboratory; Mueller, Alex H [Los Alamos National Laboratory; Steiner, Stephen A [Los Alamos National Laboratory; Luther, Erik P [Los Alamos National Laboratory

2008-01-01

A new synthetic pathway for producing nanoporous gold monoliths through combustion synthesis from Au bistetrazoJeamine complexes has been demonstrated. Applications of interest for Au nanofoams include new substrates for nanoparticle-mediated catalysis, embedded antennas, and spectroscopy. Integrated support-and-catalystin-one nanocomposites prepared through combustion synthesis of mixed AuBTA/metal oxide pellets would also be an interesting technology approach for low-cost in-line catalytic conversion media. Furthermore, we envision preparation of ultrahigh surface area gold electrodes for application in electrochemical devices through this method.

Hepatic clearance of 6 polyaromatic aromatic hydrocarbons by isolated trout livers: Prediction from in vitro clearance by liver S9 fractions

Science.gov (United States)

An isolated perfused trout liver preparation was used to evaluate in vitro-to-in vivo metabolism extrapolation procedures for fish. Hepatic clearance (CLH) studies were conducted with six polyaromatic hydrocarbons (PAH) using an experimental design wherein each liver acted as it...

Low Permeable Hydrocarbon Polymer Electrolyte Membrane for Vanadium Redox Flow Battery.

Science.gov (United States)

Jung, Ho-Young; Moon, Geon-O; Jung, Seunghun; Kim, Hee Tak; Kim, Sang-Chai; Roh, Sung-Hee

2017-04-01

Polymer electrolyte membrane (PEM) confirms the life span of vanadium redox flow battery (VRFB). Products from Dupont, Nafion membrane, is mainly used for PEM in VRFB. However, permeation of vanadium ion occurs because of Nafion’s high permeability. Therefore, the efficiency of VRFB decreases and the prices becomes higher, which hinders VRFB’s commercialization. In order to solve this problem, poly(phenylene oxide) (PPO) is sulfonated for the preparation of low-priced hydrocarbon polymer electrolyte membrane. sPPO membrane is characterized by fundamental properties and VRFB cell test.

Synthesis, structural investigation and magnetic properties of Zn{sup 2+} substituted cobalt ferrite nanoparticles prepared by the sol–gel auto-combustion technique

Energy Technology Data Exchange (ETDEWEB)

Raut, A.V., E-mail: nano9993@gmail.com [Vivekanand Arts and Sardar Dalipsingh Commerce and Science College, Aurangabad, 431004 Maharastra (India); Barkule, R.S.; Shengule, D.R. [Vivekanand Arts and Sardar Dalipsingh Commerce and Science College, Aurangabad, 431004 Maharastra (India); Jadhav, K.M., E-mail: drjadhavkm@gmail.com [Department of Physics, Dr. Babasaheb Ambedkar Marathwada University, Aurangabad, 431004 Maharastra (India)

2014-05-01

Structural morphology and magnetic properties of the Co{sub 1−x}Zn{sub x}Fe{sub 2}O{sub 4} (0.0≤x≥1.0) spinel ferrite system synthesized by the sol–gel auto-combustion technique using nitrates of respective metal ions have been studied. The ratio of metal nitrates to citric acid was taken at 1:3. The as prepared powder of cobalt zinc ferrite was sintered at 600 °C for 12 h after TG/DTA thermal studies. Compositional stoichiometry was confirmed by energy dispersive analysis of the X-ray (EDAX) technique. Single phase cubic spinel structure of Co–Zn nanoparticles was confirmed by XRD data. The average crystallite size (t), lattice constant (a) and other structural parameters of zinc substituted cobalt ferrite nanoparticles were calculated from XRD followed by SEM and FTIR. It is observed that the sol–gel auto-combustion technique has many advantages for the synthesis of technologically applicable Co–Zn ferrite nanoparticles. The present investigation clearly shows the effect of the synthesis method and possible relation between magnetic properties and microstructure of the prepared samples. Increase in nonmagnetic Zn{sup 2+} content in cobalt ferrite nanoparticles is followed by decrease in n{sub B}, M{sub s} and other magnetic parameters. Squareness ratio for the Co-ferrite was 1.096 at room temperature. - Highlights: • Co–Zn nanoparticles are prepared by sol–gel auto-combustion method. • Structural properties were characterized by XRD, SEM, and FTIR. • Compositional stoichiometry was confirmed by EDAX analysis. • Magnetic parameters were measured by the pulse field hysteresis loop technique.

High-pressure synthesis of CuBa2Ca3Cu4O10+δ superconductor from precursors prepared by a polymerized complex method

International Nuclear Information System (INIS)

Aoba, Tomoya; Bizen, Takeshi; Suzuki, Tsuneo; Nakayama, Tadachika; Suematsu, Hisayuki; Niihara, Koichi; Katsumata, Tetsuhiro; Inaguma, Yoshiyuki

2011-01-01

Samples of a CuBa 2 Ca 3 Cu 4 O 10+ δ superconductor were synthesized under a high pressure of 5 GPa at 1100-1200degC for 30 min using precursors produced by solid-state reaction and polymerized complex methods. Compared with the precursors prepared by the solid-state reaction method, the precursors produced by the polymerized complex method have low grain sizes. The superconductive transition temperature of the samples prepared using precursors made by the polymerized complex method was found to be 113 K. The volume fractions of the superconducting phase in the samples prepared using precursors made by the solid-state reaction and polymerized complex methods were 49 and 36%, respectively. From these results, precursors made by the polymerized complex method can be used in the high-pressure synthesis of superconductors similarly to those made by the solid-state reaction method. (author)

Facile preparation of superhydrophobic surface with high adhesive ...

Indian Academy of Sciences (India)

Glass substrates modified by carbon/silica composites are fabricated through a two-step process for the preparation of a superhydrophobic surface (water contact angle ≥ 150°). Carbon nanoparticles were first prepared through a deposition process on glass using a hydrothermal synthesis route, then the glass was ...

Synthesis of Organics in the Early Solar Nebula

Science.gov (United States)

Johnson, Natasha M.; Manning, S.; Nuth, J. A., III

2007-10-01

It is unknown what process or processes made the organics that are found or detected in extraterrestrial materials. One process that forms organics are Fischer-Tropsch type (FTT) reactions. Fischer-Tropsch type synthesis produces complex hydrocarbons by hydrogenating carbon monoxide via surface mediated reactions. The products of these reactions have been well-studied using `natural’ catalysts [1] and calculations of the efficiency of FTT synthesis in the Solar Nebula suggest that these types of reactions could make significant contributions to material near three AU [2]. We use FTT synthesis to coat Fe-silicate amorphous grains with organic material to simulate the chemistry in the early Solar Nebula. These coatings are composed of macromolecular organic phases [3]. Previous work also showed that as the grains became coated, Haber-Bosch type reactions took place resulting in nitrogen-bearing organics [4]. Our experiments consist of circulating CO, N2, and H2 gas through Fe- amorphous silicate grains that are maintained at a specific temperature in a closed system. The gases are passed through an FTIR spectrometer and are measured to monitor the reaction progress. Samples are analyzed using FTIR, and GCMS (including pyrolysis) and extraction techniques are used to analyze the organic coatings. These experiments show that these types of reactions are an effective means to produce complex hydrocarbons. We present the analysis of the produced organics (solid and gas phase) and the change in the production rate of several compounds as the grains become coated. Organics generated by this technique could represent the carbonaceous material incorporated in comets and meteorites. References: [1] Hayatsu and Anders 1981. Topics in Current Chemistry 99:1-37. [2] Kress and Tielens 2001. MAPS 36:75-91. [3] Johnson et al. 2004. #1876. 35th LPSC. [4] Hill and Nuth 2003. Astrobiology 3:291-304. This work was supported by a grant from NASA.

Chemical fingerprinting of hydrocarbon-contamination in soil

DEFF Research Database (Denmark)

Boll, Esther Sørensen; Nejrup, Jens; Jensen, Julie K.

2015-01-01

Chemical fingerprinting analyses of 29 hydrocarbon-contaminated soils were performed to assess the soil quality and determine the main contaminant sources. The results were compared to an assessment based on concentrations of the 16 priority polycyclic aromatic hydrocarbons pointed out by the U...... and in assessing weathering trends of hydrocarbon contamination in the soils. Multivariate data analysis of sum-normalized concentrations could as a stand-alone tool distinguish between hydrocarbon sources of petrogenic and pyrogenic origin, differentiate within petrogenic sources, and detect weathering trends....... Diagnostic ratios of PACs were not successful for source identification of the heavily weathered hydrocarbon sources in the soils. The fingerprinting of contaminated soils revealed an underestimation of PACs in petrogenic contaminated soils when the assessment was based solely on EPAPAH16. As alkyl...

Air-dust-borne associations of phototrophic and hydrocarbon-utilizing microorganisms: promising consortia in volatile hydrocarbon bioremediation.

Science.gov (United States)

Al-Bader, Dhia; Eliyas, Mohamed; Rayan, Rihab; Radwan, Samir

2012-11-01

Aquatic and terrestrial associations of phototrophic and heterotrophic microorganisms active in hydrocarbon bioremediation have been described earlier. The question arises: do similar consortia also occur in the atmosphere? Dust samples at the height of 15 m were collected from Kuwait City air, and analyzed microbiologically for phototrophic and heterotrophic hydrocarbon-utilizing microorganisms, which were subsequently characterized according to their 16S rRNA gene sequences. The hydrocarbon utilization potential of the heterotrophs alone, and in association with the phototrophic partners, was measured quantitatively. The chlorophyte Gloeotila sp. and the two cyanobacteria Nostoc commune and Leptolyngbya thermalis were found associated with dust, and (for comparison) the cynobacteria Leptolyngbya sp. and Acaryochloris sp. were isolated from coastal water. All phototrophic cultures harbored oil vapor-utilizing bacteria in the magnitude of 10(5) g(-1). Each phototrophic culture had its unique oil-utilizing bacteria; however, the bacterial composition in Leptolyngbya cultures from air and water was similar. The hydrocarbon-utilizing bacteria were affiliated with Acinetobacter sp., Aeromonas caviae, Alcanivorax jadensis, Bacillus asahii, Bacillus pumilus, Marinobacter aquaeolei, Paenibacillus sp., and Stenotrophomonas maltophilia. The nonaxenic cultures, when used as inocula in batch cultures, attenuated crude oil in light and dark, and in the presence of antibiotics and absence of nitrogenous compounds. Aqueous and diethyl ether extracts from the phototrophic cultures enhanced the growth of the pertinent oil-utilizing bacteria in batch cultures, with oil vapor as a sole carbon source. It was concluded that the airborne microbial associations may be effective in bioremediating atmospheric hydrocarbon pollutants in situ. Like the aquatic and terrestrial habitats, the atmosphere contains dust-borne associations of phototrophic and heterotrophic hydrocarbon

Synthesis of single- and double-chain fluorocarbon and hydrocarbon galactosyl amphiphiles and their anti-HIV-1 activity.

Science.gov (United States)

Faroux-Corlay, B; Clary, L; Gadras, C; Hammache, D; Greiner, J; Santaella, C; Aubertin, A M; Vierling, P; Fantini, J

2000-07-24

Galactosylceramide (GalCer) is an alternative receptor allowing HIV-1 entry into CD4(-)/GalCer(+) cells. This glycosphingolipid recognizes the V3 loop of HIV gp120, which plays a key role in the fusion of the HIV envelope and cellular membrane. To inhibit HIV uptake and infection, we designed and synthesized analogs of GalCer. These amphiphiles and bolaamphiphiles consist of single and double hydrocarbon and/or fluorocarbon chain beta-linked to galactose and galactosamine. They derive from serine (GalSer), cysteine (GalCys), and ethanolamine (GalAE). The anti-HIV activity and cytotoxicity of these galactolipids were evaluated in vitro on CEM-SS (a CD4(+) cell line), HT-29, a CD4(-) cell line expressing high levels of GalCer receptor, and/or HT29 genetically modified to express CD4. GalSer and GalAE derivatives, tested in aqueous medium or as part of liposome preparation, showed moderate anti-HIV-1 activities (IC50 in the 20-220 microM range), whereas none of the GalCys derivatives was found to be active. Moreover, only some of these anti-HIV active analogs inhibited the binding of [3H]suramin (a polysulfonyl compound which displays a high affinity for the V3 loop) to SPC3, a synthetic peptide which contains the conserved GPGRAF region of the V3 loop. Our results most likely indicate that the neutralization of the virion through masking of this conserved V3 loop region is not the only mechanism involved in the HIV-1 antiviral activity of our GalCer analogs.

Bioremediation: Technology for treating hydrocarbon-contaminated wastewater

Energy Technology Data Exchange (ETDEWEB)

Towprayoon, S.; Kuntrangwattana, S. [King Mongkut`s Institute of Technology, Bangkok (Thailand)

1996-12-31

Cutting oil wastewater from an iron and steel factory was applied to the soil windrow. Self-remediation was then compared with remediation with acclimatized indigenous microbes. The incremental reduction rate of the microorganisms and hydrocarbon-degradable microbes was slower in self-remediation than in the latter treatment. Within 30 days, when the acclimatized indigenous microbes were used, there was a significant reduction of the contaminated hydrocarbons, while self-remediation took longer to reduce to the same concentration. Various nitrogen sources were applied to the soil pile, namely, organic compost, chemical fertilizer, ammonium sulfate, and urea. The organic compost induced a high yield of hydrocarbon-degradable microorganisms, but the rate at which the cutting oil in the soil decreased was slower than when other nitrogen sources were used. The results of cutting oil degradation studied by gas chromatography showed the absence of some important hydrocarbons. The increment of the hydrocarbon-degradable microbes in the land treatment ecosystem does not necessarily correspond to the hydrocarbon reduction efficiency. 3 refs., 3 figs.

Biodegradation of petroleum hydrocarbons at low temperatures

International Nuclear Information System (INIS)

Whyte, L. G.; Greer, C W.

1999-01-01

Bioremediation of contaminated Arctic sites has been proposed as the logistically and economically most favorable solution despite the known technical difficulties. The difficulties involve the inhibition of pollutants removal by biodegradation below freezing temperatures and the relative slowness of the process to remove enough hydrocarbon pollutants during the above-freezing summer months. Despite these formidable drawbacks, biodegradation of hydrocarbon contaminants is possible even in below-zero temperatures, especially if indigenous psychrophilic and psychrotropic micro-organism are used. This paper reports results of a study involving several hydrocarbon-degrading psychrotropic bacteria and suggests bioaugmentation with specific cold-adapted organisms and/or biostimulation with commercial fertilizers for enhancing degradation of specific contaminants in soils from northern Canada. An evaluation of the biodegradation potential of hydrocarbon contaminated soils in the high Arctic suggested that the contaminated soils contained sufficient numbers of cold-adapted hydrocarbon-degrading bacteria and that the addition of fertilizer was sufficient to enhance the level of hydrocarbon degradation at low ambient summer temperatures. 9 refs., 2 tabs., 3 figs

Stable π-Extended p -Quinodimethanes: Synthesis and Tunable Ground States

KAUST Repository

Zeng, Zebing

2014-12-18

© 2014 The Chemical Society of Japan and Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. p-Quinodimethane (p-QDM) is a highly reactive hydrocarbon showing large biradical character in the ground state. It has been demonstrated that incorporation of the p-QDM moiety into an aromatic hydrocarbon framework could lead to new π-conjugated systems with significant biradical character and unique optical, electronic and magnetic properties. On the other hand, the extension of p-QDM is expected to result in molecules with even larger biradical character and higher reactivity. Therefore, the synthesis of stable π-extended p-QDMs is very challenging. In this Personal Account we will briefly discuss different stabilizing strategies and synthetic methods towards stable π-extended p-QDMs with tunable ground states and physical properties, including two types of polycyclic hydrocarbons: (1) tetrabenzo-Tschitschibabin\\'s hydrocarbons, and (2) tetracyano-rylenequinodimethanes. We will discuss how the aromaticity, substituents and steric hindrance play important roles in determining their ground states and properties. Incorporation of the p-quinodimethane moiety into aromatic hydrocarbon frameworks can lead to new π-conjugated systems with significant biradical character and unique optical, electronic and magnetic properties. Furthermore, the extension of p-QDM is expected to result in molecules with even larger biradical character and higher reactivity. In this Personal Account, different stabilizing strategies and synthetic methods towards stable π-extended p-QDMs with tunable ground states and physical properties are briefly discussed, including the roles of aromaticity, substituents and steric hindrance.

Synthesis and characterization of a molecularly imprinted polymer for the isolation of the 16 US-EPA priority polycyclic aromatic hydrocarbons (PAHs) in solution.

Science.gov (United States)

Ncube, Somandla; Kunene, Phumlile; Tavengwa, Nikita T; Tutu, Hlanganani; Richards, Heidi; Cukrowska, Ewa; Chimuka, Luke

2017-09-01

A smart sorbent consisting of benzo[k]fluoranthene-imprinted and indeno[1 2 3-cd]pyrene-imprinted polymers mixed at 1:1 (w/w) was successfully screened from several cavity-tuning experiments and used in the isolation of polycyclic aromatic hydrocarbons from spiked solution. The polymer mixture showed high cross selectivity and affinity towards all the 16 US-EPA priority polycyclic aromatic hydrocarbons. The average extraction efficiency from a cyclohexane solution was 65 ± 13.3% (n = 16, SD). Batch adsorption and kinetic studies confirmed that the binding of polycyclic aromatic hydrocarbons onto the polymer particles resulted in formation of a monolayer and that the binding process was the rate limiting step. The imprinted polymer performance studies confirmed that the synthesized polymer had an imprinting efficiency of 103.9 ± 3.91% (n = 3, SD). A comparison of the theoretical number of cavities and the experimental binding capacity showed that the overall extent of occupation of the imprinted cavities in the presence of excess polycyclic aromatic hydrocarbons was 128 ± 6.45% (n = 3, SD). The loss of selectivity was estimated at 2.9% with every elution cycle indicating that the polymer can be re-used several times with limited loss of selectivity and sensitivity. The polymer combination has shown to be an effective adsorbent that can be used to isolate all the 16 US-EPA priority polycyclic aromatic hydrocarbons in solution. Copyright © 2017 Elsevier Ltd. All rights reserved.

Preliminary Geospatial Analysis of Arctic Ocean Hydrocarbon Resources

Energy Technology Data Exchange (ETDEWEB)

Long, Philip E.; Wurstner, Signe K.; Sullivan, E. C.; Schaef, Herbert T.; Bradley, Donald J.

2008-10-01

Ice coverage of the Arctic Ocean is predicted to become thinner and to cover less area with time. The combination of more ice-free waters for exploration and navigation, along with increasing demand for hydrocarbons and improvements in technologies for the discovery and exploitation of new hydrocarbon resources have focused attention on the hydrocarbon potential of the Arctic Basin and its margins. The purpose of this document is to 1) summarize results of a review of published hydrocarbon resources in the Arctic, including both conventional oil and gas and methane hydrates and 2) develop a set of digital maps of the hydrocarbon potential of the Arctic Ocean. These maps can be combined with predictions of ice-free areas to enable estimates of the likely regions and sequence of hydrocarbon production development in the Arctic. In this report, conventional oil and gas resources are explicitly linked with potential gas hydrate resources. This has not been attempted previously and is particularly powerful as the likelihood of gas production from marine gas hydrates increases. Available or planned infrastructure, such as pipelines, combined with the geospatial distribution of hydrocarbons is a very strong determinant of the temporal-spatial development of Arctic hydrocarbon resources. Significant unknowns decrease the certainty of predictions for development of hydrocarbon resources. These include: 1) Areas in the Russian Arctic that are poorly mapped, 2) Disputed ownership: primarily the Lomonosov Ridge, 3) Lack of detailed information on gas hydrate distribution, and 4) Technical risk associated with the ability to extract methane gas from gas hydrates. Logistics may control areas of exploration more than hydrocarbon potential. Accessibility, established ownership, and leasing of exploration blocks may trump quality of source rock, reservoir, and size of target. With this in mind, the main areas that are likely to be explored first are the Bering Strait and Chukchi

Bulk and surface structure of a NixFe/Al2O3 catalyst for Fischer-Tropsch synthesis studied by Moessbauer, infrared spectroscopy and magnetic methods

International Nuclear Information System (INIS)

Boellaard, E.; Kraan, A.M. van der; Geus, J.W.

1992-01-01

Deposition precipitation of a stoichiometric nickel-ironcyanide complex onto a alumina support and subsequent calcination and reduction has resulted in the formation of a homogeneous metallic alloy which exhibits activity for Fischer-Tropsch synthesis. During hydrocarbon synthesis conditions only a fraction of the metallic phase is converted in a phase which is most likely a thermally unstable (nickel-)iron carbide. (orig.)

Process for in-situ biodegradation of hydrocarbon contaminated soil

International Nuclear Information System (INIS)

Ely, D.L.; Heffner, D.A.

1991-01-01

This patent describes an in situ process for biodegrading hydrocarbons by drawing oxygen into an undisturbed hydrocarbon contaminated zone in a fluid permeable soil. It comprises: establishing a borehole extending from the earth's surface through a hydrocarbon contaminated zone having hydrocarbon degrading microbes therein; lining the borehole with a fluid impermeable liner coaxially spaced and sealingly connected to the inside surface of the borehole and extending from the earth's surface to the hydrocarbon-contaminated zone; the liner including a fluid permeable portion extending from the lower end thereof and through at least a portion of the hydrocarbon contaminated zone, fluidly connecting a source of negative pressure to the fluid impermeable line; evacuating gas from the borehole through the fluid permeable portion of the liner at a rate sufficient to draw air from the earth's surface into the hydrocarbon containing zone; and adjusting the flow rate of the evacuated gas so that the amount of hydrocarbon biodegradation therein is within 50% of the maximum hydrocarbon biodegradation rate as detected by the volume of carbon dioxide in the evacuated gas

An improved synthesis process of calixcrown ethers and synthesis of novel calixcrown ether

International Nuclear Information System (INIS)

Wang Hairong; Zhang Ping; Wang Chunmiao; Wang Jianchen; Chen Jing

2007-01-01

The synthesis method of calixcrown ethers was simplified and improved, and 10 L- scale synthesis was carried out. In the synthesis of the intermediates of the first three steps, the synthesis of 5, 11, 17, 23-tetra-tert-butyl-25, 26, 27, 28-tetrahydroxyl-calix[4] and its dehydroxylation were considered together, the purification procedures of the former, including re-crystallization in toluene and decolorization with activated carbon, were cancelled, and thus these steps were simplified. In the synthesis of oligoethylene glycol ditosylate, the purification method was also improved and the time-consuming column chromatography was left out. In the final step, impurities were removed by repeating stirring-settlement steps, by following recrystallization, the pure product was obtained. With these measures, the whole process could be implemented easily. The industrial scale production of calixcrown ethers could be fulfilled with the improved process. In addition, a new extracant, 25, 27-bis (n-propyloxy)calix[4]-26, 28-crown-6, is prepared and identified. (authors)

Long-term olfactory memories are stabilised via protein synthesis in Camponotus fellah ants

DEFF Research Database (Denmark)

Guerrieri, Fernando Javier; D'Ettorre, Patrizia; Deveaud, J-M.

2011-01-01

-chain hydrocarbons, one paired with sucrose and the other with quinine solution. Differential conditioning leads to the formation of a long-term memory retrievable at least 72¿h after training. Long-term memory consolidation was impaired by the ingestion of cycloheximide, a protein synthesis blocker, prior...... to conditioning. Cycloheximide did not impair acquisition of either short-term memory (10¿min) or early and late mid-term memories (1 or 12¿h). These results show that, upon olfactory learning, ants form different memories with variable molecular bases. While short- and mid-term memories do not require protein...... synthesis, long-term memories are stabilised via protein synthesis. Our behavioural protocol opens interesting research avenues to explore the cellular and molecular bases of olfactory learning and memory in ants....

Hydrocarbon conversion with an attenuated superactive multimetallic catalytic composite

International Nuclear Information System (INIS)

Antos, G.J.

1981-01-01

Hydrocarbons are converted by contacting them at hydrocarbon conversion conditions with a novel attenuated superactive multimetallic catalytic composite comprising a combination of a catalytically effective amount of a pyrolyzed rhenium carbonyl component with a porous carrier material containing a uniform dispersion of catalytically effective amounts of a platinum group component, which is maintained in the elemental metallic state during the incorporation and pyrolysis of the rhenium carbonyl component, and of an iron component. In a highly preferred embodiment, this novel catalytic composite also contains a catalytically effective amount of a halogen component. The platinum group component, pyrolyzed rhenium carbonyl component, iron component and optional halogen component are preferably present in the multimetallic catalytic composite in amounts, calculated on an elemental basis, corresponding to about 0.01 to about 2 wt. % platinum group metal, about 0.01 to about 5 wt. % rhenium, about 0.005 to about 4 wt. % iron and about 0.1 to about 5 wt. % halogen. A key feature associated with the preparation of the subject catalytic composite is reaction of a rhenium carbonyl complex with a porous carrier material containing a uniform dispersion of an iron component and of a platinum group component maintained in the elemental state, whereby the interaction of the rhenium moiety with the platinum group moiety is maximized due to the platinophilic (i.e., platinum-seeking) propensities of the carbon monoxide ligands associated with the rhenium reagent. A specific example of the type of hydrocarbon conversion process disclosed herein is a process for the catalytic reforming of a low octane gasoline fraction wherein the gasoline fraction and a hydrogen stream are contacted with the attenuated superactive multimetallic catalytic composite at reforming conditions

Synthesis and Activity Test of Cu/ZnO/Al2O3 for the Methanol Steam Reforming as a Fuel Cell’s Hydrogen Supplier

Directory of Open Access Journals (Sweden)

IGBN Makertihartha

2009-05-01

Full Text Available The synthesis of hydrogen from hydrocarbons through the steam reforming of methanol on Cu/ZnO/Al2O3 catalyst has been investigated. This process is assigned to be one of the promising alternatives for fuel cell hydrogen process source. Hydrogen synthesis from methanol can be carried out by means of methanol steam reforming which is a gas phase catalytic reaction between methanol and water. In this research, the Cu/ZnO/Al2O3 catalyst prepared by the dry impregnation was used. The specific surface area of catalyst was 194.69 m2/gram.The methanol steam reforming (SRM reaction was carried out by means of the injection of gas mixture containing methanol and water with 1:1.2 mol ratio and 20-90 mL/minute feed flow rate to a fixed bed reactor loaded by 1 g of catalyst. The reaction temperature was 200-300 °C, and the reactor pressure was 1 atm. Preceding the reaction, catalyst was reduced in the H2/N2 mixture at 160 °C. This study shows that at 300 °C reaction temperature, methanol conversion reached 100% at 28 mL/minute gas flow rate. This conversion decreased significantly with the increase of gas flow rate. Meanwhile, the catalyst prepared for SRM was stable in 36 hours of operation at 260 °C. The catalyst exhibited a good stability although the reaction condition was shifted to a higher gas flow rate.

Green chemistry for nanoparticle synthesis.

Science.gov (United States)

Duan, Haohong; Wang, Dingsheng; Li, Yadong

2015-08-21

The application of the twelve principles of green chemistry in nanoparticle synthesis is a relatively new emerging issue concerning the sustainability. This field has received great attention in recent years due to its capability to design alternative, safer, energy efficient, and less toxic routes towards synthesis. These routes have been associated with the rational utilization of various substances in the nanoparticle preparations and synthetic methods, which have been broadly discussed in this tutorial review. This article is not meant to provide an exhaustive overview of green synthesis of nanoparticles, but to present several pivotal aspects of synthesis with environmental concerns, involving the selection and evaluation of nontoxic capping and reducing agents, the choice of innocuous solvents and the development of energy-efficient synthetic methods.

Synthesis of three advanced biofuels from ionic liquid-pretreated switchgrass using engineered Escherichia coli

Science.gov (United States)

Bokinsky, Gregory; Peralta-Yahya, Pamela P.; George, Anthe; Holmes, Bradley M.; Steen, Eric J.; Dietrich, Jeffrey; Soon Lee, Taek; Tullman-Ercek, Danielle; Voigt, Christopher A.; Simmons, Blake A.; Keasling, Jay D.

2011-01-01

One approach to reducing the costs of advanced biofuel production from cellulosic biomass is to engineer a single microorganism to both digest plant biomass and produce hydrocarbons that have the properties of petrochemical fuels. Such an organism would require pathways for hydrocarbon production and the capacity to secrete sufficient enzymes to efficiently hydrolyze cellulose and hemicellulose. To demonstrate how one might engineer and coordinate all of the necessary components for a biomass-degrading, hydrocarbon-producing microorganism, we engineered a microorganism naïve to both processes, Escherichia coli, to grow using both the cellulose and hemicellulose fractions of several types of plant biomass pretreated with ionic liquids. Our engineered strains express cellulase, xylanase, beta-glucosidase, and xylobiosidase enzymes under control of native E. coli promoters selected to optimize growth on model cellulosic and hemicellulosic substrates. Furthermore, our strains grow using either the cellulose or hemicellulose components of ionic liquid-pretreated biomass or on both components when combined as a coculture. Both cellulolytic and hemicellulolytic strains were further engineered with three biofuel synthesis pathways to demonstrate the production of fuel substitutes or precursors suitable for gasoline, diesel, and jet engines directly from ionic liquid-treated switchgrass without externally supplied hydrolase enzymes. This demonstration represents a major advance toward realizing a consolidated bioprocess. With improvements in both biofuel synthesis pathways and biomass digestion capabilities, our approach could provide an economical route to production of advanced biofuels. PMID:22123987

Determination of polycyclic aromatic hydrocarbons in deposited waste using GC-MSD. Bestimmung von polycyclischen aromatischen Kohlenwasserstoffen in Deponiegut mittels GC-MSD

Energy Technology Data Exchange (ETDEWEB)

Treffert, U. (chemlab, Gesellschaft fuer Analytik und Umweltberatung mbH, Bensheim (Germany). Abt. ' ' Organische Analytik' ' ); Kolb, M. (Fachhochschule Aalen (Germany)); Stoerk, H. (chemlab, Gesellschaft fuer Analytik und Umweltberatung mbH, Bensheim (Germany))

1999-06-01

The articel describes an analysis method for the determination of 16 polycyclic aromatic hydrocarbons in deposited waste. The single steps are described very detailed: sample preparation by extraction, evaporation, flash-chromatography (Al[sub 2]O[sub 3]), quantitative analysis by GC-MSD. (SR)

Comparison of Paraffin and Diesel Oil as Cultivation Medium Supplements for Preparing a Hydrocarbon-Degrading Bacterial Biomass

Directory of Open Access Journals (Sweden)

Dokukins Eduards

2016-05-01

Full Text Available The effect of liquid paraffin and diesel oil as nutrient amendments for hydrocarbon-degrading bacteria was compared. Different parameters were analyzed - optical density of bacterial suspension, oxygen consumption by biomass, morphology of bacteria, etc. In some experiments the paraffin was more preferable for microorganisms, but in other tests the results for both substances were similar. The influence of the comparable substances strongly depends on cultivation conditions.

Assessing impediments to hydrocarbon biodegradation in weathered contaminated soils.

Science.gov (United States)

Adetutu, Eric; Weber, John; Aleer, Sam; Dandie, Catherine E; Aburto-Medina, Arturo; Ball, Andrew S; Juhasz, Albert L

2013-10-15

In this study, impediments to hydrocarbon biodegradation in contaminated soils were assessed using chemical and molecular methodologies. Two long-term hydrocarbon contaminated soils were utilised which were similar in physico-chemical properties but differed in the extent of hydrocarbon (C10-C40) contamination (S1: 16.5 g kg(-1); S2: 68.9 g kg(-1)). Under enhanced natural attenuation (ENA) conditions, hydrocarbon biodegradation was observed in S1 microcosms (26.4% reduction in C10-C40 hydrocarbons), however, ENA was unable to stimulate degradation in S2. Although eubacterial communities (PCR-DGGE analysis) were similar for both soils, the alkB bacterial community was less diverse in S2 presumably due to impacts associated with elevated hydrocarbons. When hydrocarbon bioaccessibility was assessed using HP-β-CD extraction, large residual concentrations remained in the soil following the extraction procedure. However, when linear regression models were used to predict the endpoints of hydrocarbon degradation, there was no significant difference (P>0.05) between HP-β-CD predicted and microcosm measured biodegradation endpoints. This data suggested that the lack of hydrocarbon degradation in S2 resulted primarily from limited hydrocarbon bioavailability. Copyright © 2013 Elsevier B.V. All rights reserved.

Geochemical assessment of light gaseous hydrocarbons in near-surface soils of Kutch-Saurashtra: Implication for hydrocarbon prospects

Science.gov (United States)

Rao, P. Lakshmi Srinivasa; Madhavi, T.; Srinu, D.; Kalpana, M. S.; Patil, D. J.; Dayal, A. M.

2013-02-01

Light hydrocarbons in soil have been used as direct indicators in geochemical hydrocarbon exploration, which remains an unconventional path in the petroleum industry. The occurrence of adsorbed soil gases, methane and heavier homologues were recorded in the near-surface soil samples collected from Kutch-Saurashtra, India. Soil gas alkanes were interpreted to be derived from deep-seated hydrocarbon sources and have migrated to the surface through structural discontinuities. The source of hydrocarbons is assessed to be thermogenic and could have been primarily derived from humic organic matter with partial contribution from sapropelic matter. Gas chromatographic analyses of hydrocarbons desorbed from soil samples through acid extraction technique showed the presence of methane through n-butane and the observed concentrations (in ppb) vary from: methane (C1) from 4-291, ethane (C2) from 0-84, propane (C3) from 0-37, i-butane (iC4) from 0-5 and n-butane (nC4) from 0-4. Carbon isotopes measured for methane and ethane by GC-C-IRMS, range between -42.9‰ to -13.3‰ (Pee Dee Belemnite - PDB) and -21.2‰ to -12.4‰ (PDB), respectively. The increased occurrence of hydrocarbons in the areas near Anjar of Kutch and the area south to Rajkot of Saurashtra signifies the area potential for oil and gas.

Synthesis of Mikto-Arm Star Peptide Conjugates.

Science.gov (United States)

Koo, Jin Mo; Su, Hao; Lin, Yi-An; Cui, Honggang

2018-01-01

Mikto-arm star peptide conjugates are an emerging class of self-assembling peptide-based structural units that contain three or more auxiliary segments of different chemical compositions and/or functionalities. This group of molecules exhibit interesting self-assembly behavior in solution due to their chemically asymmetric topology. Here we describe the detailed procedure for synthesis of an ABC Mikto-arm star peptide conjugate in which two immiscible entities (a saturated hydrocarbon and a hydrophobic and lipophobic fluorocarbon) are conjugated onto a short β-sheet forming peptide sequence, GNNQQNY, derived from the Sup35 prion, through a lysine junction. Automated and manual Fmoc-solid phase synthesis techniques are used to synthesize the Mikto-arm star peptide conjugates, followed by HPLC purification. We envision that this set of protocols can afford a versatile platform to synthesize a new class of peptidic building units for diverse applications.

Convenient synthesis of deuterated aluminium hydrides

Energy Technology Data Exchange (ETDEWEB)

Pawelke, Roland H.; Felderhoff, Michael; Weidenthaler, Claudia [Max-Planck-Institut fuer Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Muelheim an der Ruhr (Germany); Schueth, Ferdi [Max-Planck-Institut fuer Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Muelheim an der Ruhr (Germany)], E-mail: schueth@mpi-muelheim.mpg.de

2008-09-15

We describe the ball-milling synthesis of alkali metal deuterides from commercial lithium aluminium deuteride. This reaction principle was exemplified by the mechanochemical synthesis of NaAlD{sub 4} and KAlD{sub 4}. NaAlD{sub 4} was prepared on the multi-gram scale by this procedure and purified by standard wet-chemical separation. Pure NaAlD{sub 4} was obtained and used for the synthesis of Ca(AlD{sub 4}){sub 2}. The formation of all products was verified by X-ray diffraction.

In-situ hydrocarbon delineation using laser-induced fluorescence

International Nuclear Information System (INIS)

Taer, A.D.; Hastings, R.W.; Brown, A.Y.; Frend, R.

1996-01-01

An investigation of hydrocarbons in soils was conducted at an active Shell Oil Company petroleum products terminal, located in Carson, California. An investigation approach involving Laser-Induced Fluorescence (LIF) and Cone Penetrometer Testing (CPT) technologies was implemented to provide real-time, in-situ characterization of site stratigraphy, hydrocarbon distribution and importantly, hydrocarbon product differentiation. The area of investigation is located along a property boundary, where a plume of separate phase hydrocarbons has been actively recovered for several years. CPT/LIF technology was selected for the investigation since previous delineation efforts using hydrocarbon fingerprinting methods proved inconclusive. Additionally, the CPT/LIF technology had the potential to provide a cost effective solution to accomplish project objectives. Based on the information obtained during this investigation, it was determined that the plume of separate phase hydrocarbons along the northern property boundary is from a source distinctly different than any identified hydrocarbons known to be from on-site sources. In addition, the plume was determined to not be connected with any other known on-site hydrocarbon plumes. The results of this CPT/LIF investigation were consistent with the known hydrogeologic conditions. This evaluation determined that CPT/LIF technology was very effective in addressing project objectives and resulted in a significant cost savings

Pyrochlore-type catalysts for the reforming of hydrocarbon fuels

Science.gov (United States)

Berry, David A [Morgantown, WV; Shekhawat, Dushyant [Morgantown, WV; Haynes, Daniel [Morgantown, WV; Smith, Mark [Morgantown, WV; Spivey, James J [Baton Rouge, LA

2012-03-13

A method of catalytically reforming a reactant gas mixture using a pyrochlore catalyst material comprised of one or more pyrochlores having the composition A.sub.2-w-xA'.sub.wA''.sub.xB.sub.2-y-zB'.sub.yB''.sub.zO.sub.7-.DELTA.. Distribution of catalytically active metals throughout the structure at the B site creates an active and well dispersed metal locked into place in the crystal structure. This greatly reduces the metal sintering that typically occurs on supported catalysts used in reforming reactions, and reduces deactivation by sulfur and carbon. Further, oxygen mobility may also be enhanced by elemental exchange of promoters at sites in the pyrochlore. The pyrochlore catalyst material may be utilized in catalytic reforming reactions for the conversion of hydrocarbon fuels into synthesis gas (H.sub.2+CO) for fuel cells, among other uses.

Facile synthesis of magnetic carbon nitride nanosheets and its application in magnetic solid phase extraction for polycyclic aromatic hydrocarbons in edible oil samples.

Science.gov (United States)

Zheng, Hao-Bo; Ding, Jun; Zheng, Shu-Jian; Zhu, Gang-Tian; Yuan, Bi-Feng; Feng, Yu-Qi

2016-01-01

In this study, we proposed a method to fabricate magnetic carbon nitride (CN) nanosheets by simple physical blending. Low-cost CN nanosheets prepared by urea possessed a highly π-conjugated structure; therefore the obtained composites were employed as magnetic solid-phase extraction (MSPE) sorbent for extraction of polycyclic aromatic hydrocarbons (PAHs) in edible oil samples. Moreover, sample pre-treatment time could be carried out within 10 min. Thus, a simple and cheap method for the analysis of PAHs in edible oil samples was established by coupling magnetic CN nanosheets-based MSPE with gas chromatography-mass spectrometry (GC/MS) analysis. Limits of quantitation (LOQs) for eight PAHs ranged from 0.4 to 0.9 ng/g. The intra- and inter-day relative standard deviations (RSDs) were less than 15.0%. The recoveries of PAHs for spiked soybean oil samples ranged from 91.0% to 124.1%, with RSDs of less than 10.2%. Taken together, the proposed method offers a simple and cost-effective option for the convenient analysis of PAHs in oil samples. Copyright © 2015 Elsevier B.V. All rights reserved.

Constructed wetlands for treatment of dissolved phase hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Moore, B J; Ross, S D [Komex International, Calgary, AB (Canada); Gibson, D [Calgary Univ., AB (Canada); Hardisty, P E [Komex Clarke Bond, Bristol (United Kingdom)

1999-01-01

The use of constructed wetlands as an alternative to conventional treatment of condensate-contaminated groundwater was studied. In 1997 a pilot scale wetland was constructed and implemented at the Gulf Strachan Gas Processing Plant to determine its ability in treating extracted groundwater contaminated with natural gas condensates. This paper presented the results of hydrocarbon removal efficiency, hydrocarbon removal mechanisms, winter operation, and the effect of hydrocarbons on vegetation health. The inflow water to the wetland contains 15 to 20 mg/L of C[sub 5]-C[sub 10] hydrocarbons, including 50 per cent BTEX compounds. During the summer months, hydrocarbon removal efficiency was 100 per cent, but decreased to 60 and 30 per cent in the spring and late fall, respectively. The hydrocarbons not removed in the wetland were eventually removed along the outflow channel. Temperature was determined to be an important factor in the variable removal rates, particularly when there is no aeration. The main hydrocarbon removal mechanisms appear to be volatilization, biodegradation and dilution. At present, plant uptake is not a factor. 12 refs., 1 tab., 3 figs.

Constructed wetlands for treatment of dissolved phase hydrocarbons

International Nuclear Information System (INIS)

Moore, B.J.; Ross, S.D.; Gibson, D.; Hardisty, P.E.

1999-01-01

The use of constructed wetlands as an alternative to conventional treatment of condensate-contaminated groundwater was studied. In 1997 a pilot scale wetland was constructed and implemented at the Gulf Strachan Gas Processing Plant to determine its ability in treating extracted groundwater contaminated with natural gas condensates. This paper presented the results of hydrocarbon removal efficiency, hydrocarbon removal mechanisms, winter operation, and the effect of hydrocarbons on vegetation health. The inflow water to the wetland contains 15 to 20 mg/L of C 5 -C 10 hydrocarbons, including 50 per cent BTEX compounds. During the summer months, hydrocarbon removal efficiency was 100 per cent, but decreased to 60 and 30 per cent in the spring and late fall, respectively. The hydrocarbons not removed in the wetland were eventually removed along the outflow channel. Temperature was determined to be an important factor in the variable removal rates, particularly when there is no aeration. The main hydrocarbon removal mechanisms appear to be volatilization, biodegradation and dilution. At present, plant uptake is not a factor. 12 refs., 1 tab., 3 figs

Saturated versus unsaturated hydrocarbon interactions with carbon nanostructures

Directory of Open Access Journals (Sweden)

Deivasigamani eUmadevi

2014-09-01

Full Text Available The interactions of various acyclic and cyclic hydrocarbons in both saturated and unsaturated forms with the carbon nanostructures (CNSs have been explored by using density functional theory (DFT calculations. Model systems representing armchair and zigzag carbon nanotubes (CNTs and graphene have been considered to investigate the effect of chirality and curvature of the CNSs towards these interactions. Results of this study reveal contrasting binding nature of the acyclic and cyclic hydrocarbons towards CNSs. While the saturated molecules show stronger binding affinity in acyclic hydrocarbons; the unsaturated molecules exhibit higher binding affinity in cyclic hydrocarbons. In addition, acyclic hydrocarbons exhibit stronger binding affinity towards the CNSs when compared to their corresponding cyclic counterparts. The computed results excellently corroborate the experimental observations. The interaction of hydrocarbons with graphene is more favourable when compared with CNTs. Bader’s theory of atoms in molecules has been invoked to characterize the noncovalent interactions of saturated and unsaturated hydrocarbons. Our results are expected to provide useful insights towards the development of rational strategies for designing complexes with desired noncovalent interaction involving CNSs.

Radiolysis of hydrocarbons in liquid phase (Modern state of problem)

International Nuclear Information System (INIS)

Saraeva, V.V.

1986-01-01

Problems of ionizing radiation effect on hydrocarbons and hydrocarbon systems in a liquid phase are considered. Modern representations on the mechanism of hydrocarbon radiolysis are presented. Electron moderation and ion-electron pair formation, behaviour of charged particles, excited states, radical formation and their reactions are discussed. Behaviour of certain hydrocarbon classes: alkanes, cyclic hydrocarbons, olefines, aromatic hydrocarbons as well as different hydrocarbon mixtures is considered in detail. Radiation-chemical changes in organic coolants and ways of increasing radiation resistance are considered. Polyphenyl compounds are noted to be most perspective here

Synthesis of carbon nanomaterials from different pyrolysis techniques: a review

Science.gov (United States)

Umer Zahid, Muhammad; Pervaiz, Erum; Hussain, Arshad; Shahzad, Muhammad Imran; Niazi, Muhammad Bilal Khan

2018-05-01

In the current age, the significance of carbon-based nanomaterials for many applications has made the efforts for the facile synthesis methods from abundantly available wastes in a cost-effective way. Pyrolysis in a broad spectrum is commonly employed for the synthesis of carbon nanostructures by thermally treating the organic waste. The mechanism of growth of the nanoparticles determines the functional distribution of nanoparticles based on the growing size, medium, and physio-chemical properties. Carbon nanomaterial’s growth is a complicated process which is profoundly influenced by temperature, catalyst, and type of precursor. Nowadays, significant progress has been made in improving nanomaterial’s growth techniques, opening new paths for commercial production of carbon-based nanomaterials. The most promising are the methods involving hydrocarbon-rich organic waste as the feed source. In this review, synthesis of carbon-based nanomaterials, specifically carbon nanotubes (CNTs), Carbon nanofibers (CNFs) and Graphene (G) are discussed by different pyrolysis techniques. Furthermore, the review explores recent advancements made in the context of pyrolysis.

Photoacoustic spectroscopic studies of polycyclic aromatic hydrocarbons

Science.gov (United States)

Zaidi, Zahid H.; Kumar, Pardeep; Garg, R. K.

1999-02-01

Because of their involvement in environmental pollutants, in carcinogenic activity, plastics, pharmaceuticals, synthesis of some laser dyes and presence in interstellar space etc., Polycyclic aromatic hydrocarbons (PAHs) are important. As their structure and properties can be varied systematically, they form a beautiful class of molecules for experimental and quantum chemical investigations. These molecules are being studied for last several years by using conventional spectroscopy. In recent years, Photoacoustic (PA) spectroscopy has emerged as a new non-destructive technique with unique capability and sensitivity. The PA effect is the process of generation of acoustic waves in a sample resulting from the absorption of photons. This technique not only reveals non- radiative transitions but also provides information about forbidden singlet-triplet transitions which are not observed normally by the conventional spectroscopy. The present paper deals with the spectroscopic studies of some PAH molecules by PA spectroscopy in the region 250 - 400 nm. The CNDO/S-CI method is used to calculate the electronic transitions with the optimized geometries. A good agreement is found between the experimental and calculated results.

Production of hydrocarbons of value

Energy Technology Data Exchange (ETDEWEB)

1931-06-16

A process is described for the production of hydrocarbons of great value by treating with heat and pressure carbonaceous materials such as coals, tars, mineral oils, and products of distillation and transformation of these materials, also for the refining with heat and pressure of mixed liquid hydrocarbons by means of hydrogen gas, preferably in the presence of catalysts, consisting in using as the hydrogenating gas that obtained by gasification of combustible solids after partial or complete cleaning at atmospheric or elevated pressures, by means of solid adsorbents, chemical agents or catalysts, or mixtures of these agents, the hydrocarbons being characterized by strong unsaturation, and the presence of oxygen, sulfur compounds, and oxides of nitrogen.

Total Petroleum Hydrocarbons (TPH): ToxFAQs

Science.gov (United States)

... a state: This map displays locations where Total Petroleum Hydrocarbons (TPH) is known to be present. On ... I get more information? ToxFAQs TM for Total Petroleum Hydrocarbons (TPH) ( Hidrocarburos Totales de Petróleo (TPH) ) August ...

Hydrogen storage properties of Mg-23.3wt.%Ni eutectic alloy prepared via hydriding combustion synthesis followed by mechanical milling

International Nuclear Information System (INIS)

Liquan Li; Yunfeng Zhu; Xiaofeng Liu

2006-01-01

A Mg-23.3wt.%Ni eutectic alloy was prepared by the process of hydriding combustion synthesis followed by mechanical milling (HCS+MM). The product showed a high hydriding rate at 373 K and the dehydrogenation started at temperature as low as 423 K. Several reasons contributing to the improvement in hydrogen storage properties were presented. The result of this study will provide attractive information for mobile applications of magnesium hydrogen storage materials, and the process of HCS+MM developed in this study showed its potential for synthesizing magnesium based hydrogen storage materials with novel hydriding/de-hydriding properties. (authors)

Transfer-free synthesis of doped and patterned graphene films.

Science.gov (United States)

Zhuo, Qi-Qi; Wang, Qi; Zhang, Yi-Ping; Zhang, Duo; Li, Qin-Liang; Gao, Chun-Hong; Sun, Yan-Qiu; Ding, Lei; Sun, Qi-Jun; Wang, Sui-Dong; Zhong, Jun; Sun, Xu-Hui; Lee, Shuit-Tong

2015-01-27

High-quality and wafer-scale graphene on insulating gate dielectrics is a prerequisite for graphene electronic applications. For such applications, graphene is typically synthesized and then transferred to a desirable substrate for subsequent device processing. Direct production of graphene on substrates without transfer is highly desirable for simplified device processing. However, graphene synthesis directly on substrates suitable for device applications, though highly demanded, remains unattainable and challenging. Here, we report a simple, transfer-free method capable of synthesizing graphene directly on dielectric substrates at temperatures as low as 600 °C using polycyclic aromatic hydrocarbons as the carbon source. Significantly, N-doping and patterning of graphene can be readily and concurrently achieved by this growth method. Remarkably, the graphene films directly grown on glass attained a small sheet resistance of 550 Ω/sq and a high transmittance of 91.2%. Organic light-emitting diodes (OLEDs) fabricated on N-doped graphene on glass achieved a current density of 4.0 mA/cm(2) at 8 V compared to 2.6 mA/cm(2) for OLEDs similarly fabricated on indium tin oxide (ITO)-coated glass, demonstrating that the graphene thus prepared may have potential to serve as a transparent electrode to replace ITO.

Synthesis and magnetic characterization of nickel ferrite nanoparticles prepared by co-precipitation route

Science.gov (United States)

Maaz, K.; Karim, S.; Mumtaz, A.; Hasanain, S. K.; Liu, J.; Duan, J. L.

2009-06-01

Magnetic nanoparticles of nickel ferrite (NiFe 2O 4) have been synthesized by co-precipitation route using stable ferric and nickel salts with sodium hydroxide as the precipitating agent and oleic acid as the surfactant. X-ray diffraction (XRD) and transmission electron microscope (TEM) analyses confirmed the formation of single-phase nickel ferrite nanoparticles in the range 8-28 nm depending upon the annealing temperature of the samples during the synthesis. The size of the particles ( d) was observed to be increasing linearly with annealing temperature of the sample while the coercivity with particle size goes through a maximum, peaking at ˜11 nm and then decreases for larger particles. Typical blocking effects were observed below ˜225 K for all the prepared samples. The superparamagnetic blocking temperature ( T B) was found to be increasing with increasing particle size that has been attributed to the increased effective anisotropy energy of the nanoparticles. The saturation moment of all the samples was found much below the bulk value of nickel ferrite that has been attributed to the disordered surface spins or dead/inert layer in these nanoparticles.

Process for the preparation of ammonia and heavy water

International Nuclear Information System (INIS)

Mandrin, C.

1980-01-01

A process for the production of ammonia and heavy water comprises the steps of enriching a flow of water with deuterium in a monothermal isotropic process; supplying a first portion of the deuterium-enriched water to a heavy water preparation plant to produce heavy water and hydrogen; storing a second portion of the deuterium-enriched water substantially without interruption during the colder half of a year; electrolytically dissociating the stored deuterium-enriched water substantially without interruption during the wamer half of a year to form hydrogen; storing a portion of the electrolytically-produced hydrogen during said warmer half of a year while supplying the remainder to a synthesis circuit of a synthesizing plant and subsequently supplying the stored hydrogen to the synthesis circuit during said colder half of a year; removing some of the synthesis gas mixture from the synthesis circuit of the synthesizing plant; burning the removed synthesis gas mixture with air to produce a mixture consisting mainly of water and nitrogen; thereafter condensing and separating the water from the mixture of water and nitrogen; supplying the nitrogen of the mixture of water and nitrogen, the hydrogen from the heavy water preparation plant and the electrolytically-produced hydrogen to the synthesis circuit of the synthesizing plant to produce ammonia; and collecting deuterium-depleted water resulting from said burning step and feeding the collected deuterium-depleted water into the monothermal process

The offshore hydrocarbon releases (HCR) database

International Nuclear Information System (INIS)

Bruce, R.A.P.

1995-01-01

Following Cullen Recommendation 39 which states that: ''The regulatory body should be responsible for maintaining a database with regard to hydrocarbon leaks, spills, and ignitions in the Industry and for the benefit of Industry'', HSE Offshore Safety Division (HSE-OSD) has now been operating the Hydrocarbon Releases (HCR) Database for approximately 3 years. This paper deals with the reporting of Offshore Hydrocarbon Releases, the setting up of the HCR Database, the collection of associated equipment population data, and the main features and benefits of the database, including discussion on the latest output information. (author)

Sustainable treatment of hydrocarbon-contaminated industrial land

OpenAIRE

Cunningham, Colin John

2012-01-01

Land contamination by petroleum hydrocarbons is a widespread and global environmental pollution issue from recovery and refining of crude oil and the ubiquitous use of hydrocarbons in industrial processes and applications. Sustainable treatment of hydrocarbon-contaminated industrial land was considered with reference to seven published works on contaminated railway land including the track ballast, crude oil wastes and contaminated refinery soils. A methodology was developed...

Magneto-thermal and dielectric properties of biferroic YCrO3 prepared by combustion synthesis

International Nuclear Information System (INIS)

Duran, A.; Arevalo-Lopez, A.M.; Castillo-Martinez, E.; Garcia-Guaderrama, M.; Moran, E.; Cruz, M.P.; Fernandez, F.; Alario-Franco, M.A.

2010-01-01

Microstructural, magnetothermal and dielectric properties of YCrO 3 powders prepared by combustion and solid state methods have been studied by a combination of XRD, specific heat, magnetization and permittivity measurements. The TEM and XRD characterization confirm that the combustion powders are amorphous plate-like agglomerates of nano-sized crystalline particles. A more uniform grain size along with an increase of the relative density is observed by SEM in the sintered samples prepared by combustion route with respect to those produced by solid state reaction. Similar to the material obtained through solid state synthesis, the material prepared by the combustion method also shows spin canted antiferromagnetic ordering of Cr +3 (S=3/2) at ∼140 K, which is shown by magnetization as well as λ-type anomaly in the total specific heat. Furthermore, the magnetic contribution to the total specific heat reveals spin fluctuations above T N and a spin reorientation transition at about 60 K. Both YCrO 3 compounds show a diffuse phase transition at about 450 K, typical of a relaxor ferroelectric, which is characterized by a broad peak in the real part of the dielectric permittivity as a function of temperature, with the peak decreasing in magnitude and shifting to higher temperature as the frequency increases. The relaxor dipoles are due to the local non-centrosymmetric structure. Furthermore, the high loss tangent in a broad range of temperature as well as conductivity analysis indicates a hopping mechanism for the electronic conductivity as we believe it is a consequence of the outer d 3 -shell, which have detrimental effects on the polarization and the pooling process in the YCrO 3 bulk material. The more uniform particle size and higher density material synthesized through the combustion process leads to an improvement in the dielectric Properties. - Graphical abstract: Combustion method: An alternative route for synthesized a new family of multiferroics. Amorphous

Concentration of polycyclic aromatic hydrocarbons in water samples from different stages of treatment

Science.gov (United States)

Pogorzelec, Marta; Piekarska, Katarzyna

2017-11-01

The aim of this study was to analyze the presence and concentration of selected polycyclic aromatic hydrocarbons in water samples from different stages of treatment and to verify the usefulness of semipermeable membrane devices for analysis of drinking water. For this purpose, study was conducted for a period of 5 months. Semipermeable membrane devices were deployed in a surface water treatment plant located in Lower Silesia (Poland). To determine the effect of water treatment on concentration of PAHs, three sampling places were chosen: raw water input, stream of water just before disinfection and treated water output. After each month of sampling SPMDs were changed for fresh ones and prepared for further analysis. Concentrations of fifteen polycyclic aromatic hydrocarbons were determined by high performance liquid chromatography (HPLC). Presented study indicates that the use of semipermeable membrane devices can be an effective tool for the analysis of aquatic environment, including monitoring of drinking water, where organic micropollutants are present at very low concentrations.

Concentration of polycyclic aromatic hydrocarbons in water samples from different stages of treatment

Directory of Open Access Journals (Sweden)

Pogorzelec Marta

2017-01-01

Full Text Available The aim of this study was to analyze the presence and concentration of selected polycyclic aromatic hydrocarbons in water samples from different stages of treatment and to verify the usefulness of semipermeable membrane devices for analysis of drinking water. For this purpose, study was conducted for a period of 5 months. Semipermeable membrane devices were deployed in a surface water treatment plant located in Lower Silesia (Poland. To determine the effect of water treatment on concentration of PAHs, three sampling places were chosen: raw water input, stream of water just before disinfection and treated water output. After each month of sampling SPMDs were changed for fresh ones and prepared for further analysis. Concentrations of fifteen polycyclic aromatic hydrocarbons were determined by high performance liquid chromatography (HPLC. Presented study indicates that the use of semipermeable membrane devices can be an effective tool for the analysis of aquatic environment, including monitoring of drinking water, where organic micropollutants are present at very low concentrations.

Two-stage Catalytic Reduction of NOx with Hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Umit S. Ozkan; Erik M. Holmgreen; Matthew M. Yung; Jonathan Halter; Joel Hiltner

2005-12-21

A two-stage system for the catalytic reduction of NO from lean-burn natural gas reciprocating engine exhaust is investigated. Each of the two stages uses a distinct catalyst. The first stage is oxidation of NO to NO{sub 2} and the second stage is reduction of NO{sub 2} to N{sub 2} with a hydrocarbon. The central idea is that since NO{sub 2} is a more easily reduced species than NO, it should be better able to compete with oxygen for the combustion reaction of hydrocarbon, which is a challenge in lean conditions. Early work focused on demonstrating that the N{sub 2} yield obtained when NO{sub 2} was reduced was greater than when NO was reduced. NO{sub 2} reduction catalysts were designed and silver supported on alumina (Ag/Al{sub 2}O{sub 3}) was found to be quite active, able to achieve 95% N{sub 2} yield in 10% O{sub 2} using propane as the reducing agent. The design of a catalyst for NO oxidation was also investigated, and a Co/TiO{sub 2} catalyst prepared by sol-gel was shown to have high activity for the reaction, able to reach equilibrium conversion of 80% at 300 C at GHSV of 50,000h{sup -1}. After it was shown that NO{sub 2} could be more easily reduced to N{sub 2} than NO, the focus shifted on developing a catalyst that could use methane as the reducing agent. The Ag/Al{sub 2}O{sub 3} catalyst was tested and found to be inactive for NOx reduction with methane. Through iterative catalyst design, a palladium-based catalyst on a sulfated-zirconia support (Pd/SZ) was synthesized and shown to be able to selectively reduce NO{sub 2} in lean conditions using methane. Development of catalysts for the oxidation reaction also continued and higher activity, as well as stability in 10% water, was observed on a Co/ZrO{sub 2} catalyst, which reached equilibrium conversion of 94% at 250 C at the same GHSV. The Co/ZrO{sub 2} catalyst was also found to be extremely active for oxidation of CO, ethane, and propane, which could potential eliminate the need for any separate

Preparation of ubiquitin-conjugated proteins using an insect cell-free protein synthesis system.

Science.gov (United States)

Suzuki, Takashi; Ezure, Toru; Ando, Eiji; Nishimura, Osamu; Utsumi, Toshihiko; Tsunasawa, Susumu

2010-01-01

Ubiquitination is one of the most significant posttranslational modifications (PTMs). To evaluate the ability of an insect cell-free protein synthesis system to carry out ubiquitin (Ub) conjugation to in vitro translated proteins, poly-Ub chain formation was studied in an insect cell-free protein synthesis system. Poly-Ub was generated in the presence of Ub aldehyde (UA), a de-ubiquitinating enzyme inhibitor. In vitro ubiquitination of the p53 tumor suppressor protein was also analyzed, and p53 was poly-ubiquitinated when Ub, UA, and Mdm2, an E3 Ub ligase (E3) for p53, were added to the in vitro reaction mixture. These results suggest that the insect cell-free protein synthesis system contains enzymatic activities capable of carrying out ubiquitination. CBB-detectable ubiquitinated p53 was easily purified from the insect cell-free protein synthesis system, allowing analysis of the Ub-conjugated proteins by mass spectrometry (MS). Lys 305 of p53 was identified as one of the Ub acceptor sites using this strategy. Thus, we conclude that the insect cell-free protein synthesis system is a powerful tool for studying various PTMs of eukaryotic proteins including ubiqutination presented here.

Targeting of insect epicuticular lipids by the entomopathogenic fungus Beauveria bassiana: hydrocarbon oxidation within the context of a host-pathogen interaction

Science.gov (United States)

Pedrini, Nicolás; Ortiz-Urquiza, Almudena; Huarte-Bonnet, Carla; Zhang, Shizhu; Keyhani, Nemat O.

2013-01-01

Broad host range entomopathogenic fungi such as Beauveria bassiana attack insect hosts via attachment to cuticular substrata and the production of enzymes for the degradation and penetration of insect cuticle. The outermost epicuticular layer consists of a complex mixture of non-polar lipids including hydrocarbons, fatty acids, and wax esters. Long chain hydrocarbons are major components of the outer waxy layer of diverse insect species, where they serve to protect against desiccation and microbial parasites, and as recognition molecules or as a platform for semiochemicals. Insect pathogenic fungi have evolved mechanisms for overcoming this barrier, likely with sets of lipid degrading enzymes with overlapping substrate specificities. Alkanes and fatty acids are substrates for a specific subset of fungal cytochrome P450 monooxygenases involved in insect hydrocarbon degradation. These enzymes activate alkanes by terminal oxidation to alcohols, which are further oxidized by alcohol and aldehyde dehydrogenases, whose products can enter β-oxidation pathways. B. bassiana contains at least 83 genes coding for cytochrome P450s (CYP), a subset of which are involved in hydrocarbon oxidation, and several of which represent new CYP subfamilies/families. Expression data indicated differential induction by alkanes and insect lipids and four CYP proteins have been partially characterized after heterologous expression in yeast. Gene knockouts revealed a phenotype for only one (cyp52X1) out of six genes examined to date. CYP52X1 oxidizes long chain fatty acids and participates in the degradation of specific epicuticular lipid components needed for breaching the insect waxy layer. Examining the hydrocarbon oxidizing CYP repertoire of pathogens involved in insect epicuticle degradation can lead to the characterization of enzymes with novel substrate specificities. Pathogen targeting may also represent an important co-evolutionary process regarding insect cuticular hydrocarbon

Hydrocarbon toxicity: an analysis of AAPCC TESS data.

Science.gov (United States)

Cobaugh, Daniel J; Seger, Donna L; Krenzelok, Edward P

2007-01-01

Human hydrocarbon exposures have the potential to cause significant morbidity and mortality. To determine which hydrocarbons were associated with the most severe adverse outcomes, human exposure data reported to American poison information centers were analyzed. Outcome data for single-substance, hydrocarbon exposures reported to the American Association of Poison Control Centers Toxic Exposure Surveillance System from 1994 through 2003 were analyzed. Only cases with definitive medical outcomes were included. Analyses were stratified by five age groups: 59 years. Hazard factors were determined by calculating the sum of the major effects and fatalities for each hydrocarbon category and dividing this by the total number of exposures for that category. To normalize the data, the overall rate of major effects and deaths for each age group was assigned hazard factor value of 1. Hydrocarbon categories with a HF of > or = 1.5 were included in the final analyses. Estimated rates of major effect and fatal outcomes (outcomes/1000 people) were also calculated. 318,939 exposures were analyzed. Exposures to benzene, toluene/xylene, halogenated hydrocarbons, kerosene and lamp oil resulted in the highest hazard factor values. These data demonstrate that hydrocarbons that are absorbed systemically and those with low viscosities are associated with higher hazard factors. The risks associated with hydrocarbons often implicated in abuse by older children and adolescents are also confirmed.

Synthesis of crystalline ceramics for actinide immobilisation

International Nuclear Information System (INIS)

Burakov, B.; Gribova, V.; Kitsay, A.; Ojovan, M.; Hyatt, N.C.; Stennett, M.C.

2007-01-01

Methods for the synthesis of ceramic wasteforms for the immobilization of actinides are common to those for non-radioactive ceramics: hot uniaxial pressing (HUP); hot isostatic pressing (HIP); cold pressing followed by sintering; melting (for some specific ceramics, such as garnet/perovskite composites). Synthesis of ceramics doped with radionuclides is characterized with some important considerations: all the radionuclides should be incorporated into crystalline structure of durable host-phases in the form of solid solutions and no separate phases of radionuclides should be present in the matrix of final ceramic wasteform; all procedures of starting precursor preparation and ceramic synthesis should follow safety requirements of nuclear industry. Synthesis methods that avoid the use of very high temperatures and pressures and are easily accomplished within the environment of a glove-box or hot cell are preferable. Knowledge transfer between the V. G. Khlopin Radium Institute (KRI, Russia) and Immobilisation Science Laboratory (ISL, UK) was facilitated in the framework of a joint project supported by UK Royal Society. In order to introduce methods of precursor preparation and ceramic synthesis we selected well-known procedures readily deployable in radiochemical processing plants. We accounted that training should include main types of ceramic wasteforms which are currently discussed for industrial applications. (authors)

Regulation of protein synthesis during sea urchin early development

International Nuclear Information System (INIS)

Kelso, L.C.

1989-01-01

Fertilization of the sea urchin egg results in a 20-40 fold increase in the rate of protein synthesis. The masked message hypothesis proposes that mRNAs are masked or unavailable for translation in the egg. We devised an in vivo assay to test this hypothesis. Our results show that masked mRNAs limit protein synthesis in the unfertilized egg. In addition, we show that protein synthesis is also regulated at the level of translational machinery. Following fertilization is a period of rapid cell divisions. This period, known as the rapid cleavage stage, is characterized by the transient synthesis of a novel set of proteins. The synthesis of these proteins is programmed by maternal mRNAs stored in the unfertilized egg. To study the behavior of these mRNAs, we prepared a cDNA library from polysomal poly (A+) RNA from 2-hour embryos. [ 32 P] labeled probes, prepared from the cDNA library, were used to monitor the levels of individual mRNAs in polysomes at fertilization and during early development

Thermophilic slurry-phase treatment of petroleum hydrocarbon waste sludges

International Nuclear Information System (INIS)

Castaldi, F.J.; Bombaugh, K.J.; McFarland, B.

1995-01-01

Chemoheterotrophic thermophilic bacteria were used to achieve enhanced hydrocarbon degradation during slurry-phase treatment of oily waste sludges from petroleum refinery operations. Aerobic and anaerobic bacterial cultures were examined under thermophilic conditions to assess the effects of mode of metabolism on the potential for petroleum hydrocarbon degradation. The study determined that both aerobic and anaerobic thermophilic bacteria are capable of growth on petroleum hydrocarbons. Thermophilic methanogenesis is feasible during the degradation of hydrocarbons when a strict anaerobic condition is achieved in a slurry bioreactor. Aerobic thermophilic bacteria achieved the largest apparent reduction in chemical oxygen demand, freon extractable oil, total and volatile solid,s and polycyclic aromatic hydrocarbons (PAHs) when treating oily waste sludges. The observed shift with time in the molecular weight distribution of hydrocarbon material was more pronounced under aerobic metabolic conditions than under strict anaerobic conditions. The changes in the hydrocarbon molecular weight distribution, infrared spectra, and PAH concentrations during slurry-phase treatment indicate that the aerobic thermophilic bioslurry achieved a higher degree of hydrocarbon degradation than the anaerobic thermophilic bioslurry during the same time period

Preparation of synthetic standard minerals

International Nuclear Information System (INIS)

Herrick, C.C.; Bustamante, S.J.; Charls, R.W.; Cowan, R.E.; Hakkila, E.A.; Hull, D.E.; Olinger, B.W.; Roof, R.B.; Sheinberg, H.; Herrick, G.C.

1978-01-01

A number of techniques for synthetic mineral preparations have been examined. These techniques include hot-pressing in graphite dies at moderate pressures, high-pressure, high-temperature synthesis in a piston and cylinder apparatus, isostatic pressing under helium gas pressures, hydrous mineral preparations using water as the pressure medium, explosion-generated shock waves, and radiofrequency heating. Minerals suitable for equation-of-state studies (three-inch, high-density discs), for thermodynamic property determinations (low-density powders) and for microprobe standards (fusion-cast microbeads) have been prepared. Mechanical stress-strain calculations in the piston-cylinder apparatus have been initiated and their integration with thermal stress calculations is currently under investigation

Syn-Rift Systems of East Godavari Sub Basin: Its Evolution and Hydrocarbon Prospectivity

Science.gov (United States)

Dash, J., Jr.; Zaman, B.

2014-12-01

Krishna Godavari (K.G.) basin is a passive margin basin developed along the Eastern coast of India. This basin has a polyhistoric evolution with multiple rift systems. Rift basin exploration has provided the oil and gas industry with almost one third of discovered global hydrocarbon resources. Understanding synrift sequences, their evolution, depositional styles and hydrocarbon prospectivity has become important with recent discovery of the wells, G-4-6,YS-AF and KG-8 in the K.G. offshore basin. The East Godavari subbasin is a hydrocarbon producing basin from synrift and pre-rift sediments, and hence this was selected as the study area for this research. The study has been carried out by utilizing data of around 58 wells (w1-w58) drilled in the study area 25 of which are hydrocarbon bearing with organic thickness varying from 200 m to 600 m. Age data generated by palaentology and palynology studies have been utilized for calibration of key well logs to differentiate between formations within prerift and synrift sediments. The electrologs of wells like resistivity, gamma ray, neutron, density and sonic logs have been utilized for correlation of different formations in all the drilled wells. The individual thicknesses of sand, shale and coal in the formations have been calculated and tabulated. For Golapalli formation, the isopach and isolith maps were generated which revealed that there were four depocentres with input from the north direction. Schematic geological cross sections were prepared using the well data and seismic data to understand the facies variation across the basin. The sedimentological and petrophysical analysis reports and electro log suites were referred to decipher the environment of deposition, the reservoir characteristics, and play types. The geochemical reports [w4 (Tmax)= 455-468 °C; w1 (Tmax) = 467-514 °C; w4(VRO)= 0.65-0.85; w1(VRO)= 0.83-1.13] revealed the source facies, its maturation and migration timings i.e. the petroleum systems

1-[18F]fluoro-2-propanol p-toluenesulfonate: a synthon for the preparation of N-([18F]fluoroisopropyl)amines

International Nuclear Information System (INIS)

Groot, T.J. de; Elsinga, P.H.; Visser, G.M.; Vaalburg, W.

1992-01-01

The new radiochemical synthon 1-[ 18 F]fluoro-2-propanol p-toluenesulfonate is prepared with a radiochemical yield of 45% [corrected for decay to beginning of synthesis, synthesis time 40 min]. This compound is used to prepare the [ 18 F]fluoroisopropyl-alkylated derivatives of benzylamine and norephedrine with a yield of 7 and 2% respectively, (synthesis time 90 min). This alkylation reaction a good perspective for the preparation of [ 18 F]fluoro-labelled analogues of β 1 -adrenergic receptor binding ligands for PET. (Author)

Essentials of inorganic materials synthesis

CERN Document Server

Rao, C N R

2015-01-01

This compact handbook describes all the important methods of synthesis employed today for synthesizing inorganic materials. Some features: Focuses on modern inorganic materials with applications in nanotechnology, energy materials, and sustainability Synthesis is a crucial component of materials science and technology; this book provides a simple introduction as well as an updated description of methods Written in a very simple style, providing references to the literature to get details of the methods of preparation when required

Principles of asymmetric synthesis

CERN Document Server

Gawley, Robert E; Aube, Jeffrey

2012-01-01

The world is chiral. Most of the molecules in it are chiral, and asymmetric synthesis is an important means by which enantiopure chiral molecules may be obtained for study and sale. Using examples from the literature of asymmetric synthesis, this book presents a detailed analysis of the factors that govern stereoselectivity in organic reactions. After an explanation of the basic physical-organic principles governing stereoselective reactions, the authors provide a detailed, annotated glossary of stereochemical terms. A chapter on "Practical Aspects of Asymmetric Synthesis" provides a critical overview of the most common methods for the preparation of enantiomerically pure compounds, techniques for analysis of stereoisomers using chromatographic, spectroscopic, and chiroptical methods. The authors then present an overview of the most important methods in contemporary asymmetric synthesis organized by reaction type. Thus, there are four chapters on carbon-carbon bond forming reactions, one chapter on reductions...

X-ray excited optical luminescence of polynuclear aromatic hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Oestreich, G.J.

1979-05-01

X-ray excited optical luminescence (XEOL) coupled with time resolved spectroscopy was employed to analyze polynuclear aromatic hydrocarbons (PAH) in n-alkane solvents at 10 K. A pulsed XEOL system which was designed around minicomputer control of a medical x-ray unit was developed. Computer software which generated variable width x-ray pulses, monitored timing reference pulses, controlled data acquisition, and analyzed data was written. Phosphorescence decay constants of several PAHs were determined. Synthetic mixtures of zone refined PAHs were prepared and time resolved with the pulsed XEOL technique. Analytical results obtained from the five component mixtures of PAHs at the part per million level were tabulated. Systematic improvements and further development of the pulsed XEOL method were considered.

Degradation of volatile hydrocarbons from steam-classified solid waste by a mixture of aromatic hydrocarbon-degrading bacteria.

Science.gov (United States)

Leahy, Joseph G; Tracy, Karen D; Eley, Michael H

2003-03-01

Steam classification is a process for treatment of solid waste that allows recovery of volatile organic compounds from the waste via steam condensate and off-gases. A mixed culture of aromatic hydrocarbon-degrading bacteria was used to degrade the contaminants in the condensate, which contained approx. 60 hydrocarbons, of which 38 were degraded within 4 d. Many of the hydrocarbons, including styrene, 1,2,4-trimethylbenzene, naphthalene, ethylbenzene, m-/p-xylene, chloroform, 1,3-dichloropropene, were completely or nearly completely degraded within one day, while trichloroethylene and 1,2,3-trichloropropane were degraded more slowly.

Synthesis and properties of butadiene-alpha-methylstyrene thermoplastic elastomer

Directory of Open Access Journals (Sweden)

A. V. Firsova

2016-01-01

Full Text Available Butadiene-α-methylstyrene block – copolymer – a thermoplastic elastomer (TPE-R DMST occupies a special place among the ethylene – vinyl aromatic block copolymers. TPE-R DMST comprising as plastic – poly-α-methylstyrene unit and elastic – polybutadiene block. TPE-R DMST has high heat resistance, flexibility, abrasion resistance compared to butadiene-styrene thermoplastic elastomer (TPE DST. The synthesis of block copolymers of butadiene and α-methylstyrene was carried out. The process of polymerization the α-methylstyrene characterized the high speed of polymerization in polar medium and low reaction speed in hydrocarbon solvents. Anionic catalyst nbutyllithium (n-BuLi and high concentration – 60–80% α-methylstyrene in the mixture influenced by synthesis of the 1st block of TPE-R DMST, it’s technologically difficult. Found that the low temperature of polymerization α-methylstyrene (+61 o C, the reversibility of these reactions and the high concentration of residual monomer are very importance. It was revealed that a high polymerization rate α-methylstyrene can be achieved by conducting the reaction in a hydrocarbon solvent with polar additives compounds such as tetrahydrofuran (THF and methyl tert-butyl ether (MTBE. The conditions for the synthesis of P-DMST were developed. The kinetics of polymerization for the first DMST-P unit was obtained. Analysis of physical and mechanical properties DMST-P samples was conducted. The optimum content of bound α-methylstyrene block copolymer provides a good combination of properties in a relatively wide temperature range. The tensile strength at normal and elevated temperatures, the hardness and the stiffness of the polymer increased by increasing the content of bound α-methylstyrene. The elongation and the elasticity reduced by increasing the content of bound α-methylstyrene.

Enantioselective synthesis of almorexant via iridium-catalysed intramolecular allylic amidation

NARCIS (Netherlands)

Fananas Mastral, Martin; Teichert, Johannes F.; Fernandez-Salas, Jose Antonio; Heijnen, Dorus; Feringa, Ben L.

2013-01-01

An enantioselective synthesis of almorexant, a potent antagonist of human orexin receptors, is presented. The chiral tetrahydroisoquinoline core structure was prepared via iridium-catalysed asymmetric intramolecular allylic amidation. Further key catalytic steps of the synthesis include an oxidative

Production of hydrocarbons, especially ethylene

Energy Technology Data Exchange (ETDEWEB)

1952-01-17

The invention has for its object a process for the production of gaseous nonsaturated hydrocarbons, particularly ethylene and aromatic hydrocarbons, by starting with hydrocarbon oils entirely of paraffinic nature or their fractions, which consists in putting the separated products in contact with solid inert material especially with porous nonmetallic inert material or of heavy metals or their alloys, maybe in a finely divided state or in the form, of pieces or chips, at a temperature above 500/sup 0/C, or better between 600 and 700/sup 0/C at a velocity per hour of 0.6 to 3.0, and preferably 0.75 to 1.5 parts per volume of products per each part of space volume of catalyst.

Process of distilling heavy hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

1929-12-03

This invention has for its object the distillation of heavy liquid hydrocarbons for the purpose of obtaining lighter hydrocarbons stable and immediately salable for fuels in combustion motors. The process is distinguished by the fact that the heavy hydrocarbon is distilled by means of heating to a temperature in keeping with the nature of the material to be treated up to 350/sup 0/C under pressure or without pressure the distillation being carried out on catalysts containing successively nickel, copper, and iron (3 parts of nickel, 1 part of copper, and 1 part of iron), the vapors produced by this distillation being exposed in turn to the action of catalysts of the same nature and in the same proportion.

Method for upgrading diene-containing hydrocarbon mixtures

Energy Technology Data Exchange (ETDEWEB)

Kidwell, L.E. Jr.; Holcomb, D.E.

1984-05-22

There is disclosed a method for upgrading of hydrocarbon mixtures, so as to reduce their content of gum precursors such as diolefins and pseudo-diolefins, and provide a resulting product mixture suitable for mild hydrogenation, for use as a motor fuel or as a feed stock to an extraction unit. The process comprises obtaining a hydrocarbon mixture containing about 60-90 wt. % of aromatic components, about 3-40 wt. % of dienes and pseudodienes, and monoolefins, and up to about 6 wt. % of relatively unreactive organic compounds, reacting this mixture with elemental sulfur in the approximate weight ratio of about 5-95 wt. % of the hydrocarbon mixture with about 95-5 wt. % of elemental sulfur, the reaction being carried out at a temperature in the range of 100/sup 0/-150/sup 0/ C. for about 10 minutes to 24 hours with good mixing, removing the unreacted materials by distillation and separating a sulfur-hydrocarbon reaction product to provide the upgraded hydrocarbon mixture.

Effect of hydrocarbons on plasma treatment of NOx

Energy Technology Data Exchange (ETDEWEB)

Penetrante, B.M.; Pitz, W.J.; Hsaio, M.C.; Merritt, B.T.; Vogtlin, G.E. [Lawrence Livermore National Lab., CA (United States)

1997-12-31

Lean burn gasoline engine exhausts contain a significant amount of hydrocarbons in the form of propene. Diesel engine exhausts contain little gaseous hydrocarbon; however, they contain a significant amount of liquid-phase hydrocarbons (known as the volatile organic fraction) in the particulates. The objective of this paper is to examine the fate of NO{sub x} when an exhaust gas mixture that contains hydrocarbons is subjected to a plasma. The authors will show that the hydrocarbons promote the oxidation of NO to NO{sub 2}, but not the reduction of NO to N{sub 2}. The oxidation of NO to NO{sub 2} is strongly coupled with the hydrocarbon oxidation chemistry. This result suggests that gas-phase reactions in the plasma alone cannot lead to the chemical reduction of NO{sub x}. Any reduction of NO{sub x} to N{sub 2} can only be accomplished through heterogeneous reactions of NO{sub 2} with surfaces or particulates.

Investigating Superhydrogenated Polycyclic Aromatic Hydrocarbons as catalysts for Interstellar H2 formation

DEFF Research Database (Denmark)

Simonsen, Frederik Doktor Skødt

2016-01-01

Temperature programmed desorption has been used to investigate adsorption and abstraction of hydrogen atoms on the polycyclic aromatic hydrocarbon, coronene. The coronene molecules were exposed to different hydrogen fluences at a dosing temperature of 1000K. Large fluences of hydrogen leave...... large abundances, alongside H2[2]. To investigate the the abstraction and adsoption patterns of hydrogen/deuterium on coronene, C24H12 (a PAH), we used temperature programmed desorption (TPD). Coronene monolayers were prepared on graphite and exposed to different fluences of 1000 K H or D atoms...

Molecular characterization of autochthonous hydrocarbon utilizing ...

African Journals Online (AJOL)

Prof. Ogunji

Materials and Methods ... culturable hydrocarbon utilizing bacteria (HUB) were enumerated by vapour phase ... hydrocarbon utilizing bacterial isolates by boiling method according to ... obtained in this investigation are consistent with past field studies (Kostka et ... Microbial and other related changes in a Niger sediment.

Preparation of 99Mo/99mTc generators based on 99Mo zirconium molybdates in the Gel Synthesis Device for Generators

International Nuclear Information System (INIS)

Lopez M, I. Z.; Monroy G, F.; Rivero G, T.; Rojas N, P.

2008-01-01

The 99m Tc is used for diagnosis and therapy. It is produced commercially from 99 Mo obtained from the fission of 235 U, which is retained in chromatographic columns filled with alumina whose maximum capacity is 0.2%. Given these constraints new methods of preparation 99 Mo/ 99m Tc generators have been developed using zirconium molybdates gels containing up to 30% of Mo, which is part of the generator matrix, and retaining quality and purity similar characteristics to those commercial generators. The present study aims to determine the flow of agitation, temperature and drying time optimal to prepare 99 Mo/ 99m Tc generators based on 99 Mo zirconium molybdates in the Gel Synthesis Device 99 Mo/ 99m Tc Generators designed and built by groups of the Radioactive Materials Research Laboratory and Automation and Instrumentation Department of the National Institute of Nuclear Research. (Author)

Enzymatic biodiesel synthesis. Key factors affecting efficiency of the process

Energy Technology Data Exchange (ETDEWEB)

Szczesna Antczak, Miroslawa; Kubiak, Aneta; Antczak, Tadeusz; Bielecki, Stanislaw [Institute of Technical Biochemistry, Faculty of Biotechnology and Food Sciences, Technical University of Lodz, Stefanowskiego 4/10, 90-924 Lodz (Poland)

2009-05-15

Chemical processes of biodiesel production are energy-consuming and generate undesirable by-products such as soaps and polymeric pigments that retard separation of pure methyl or ethyl esters of fatty acids from glycerol and di- and monoacylglycerols. Enzymatic, lipase-catalyzed biodiesel synthesis has no such drawbacks. Comprehension of the latter process and an appreciable progress in production of robust preparations of lipases may soon result in the replacement of chemical catalysts with enzymes in biodiesel synthesis. Engineering of enzymatic biodiesel synthesis processes requires optimization of such factors as: molar ratio of substrates (triacylglycerols: alcohol), temperature, type of organic solvent (if any) and water activity. All of them are correlated with properties of lipase preparation. This paper reports on the interplay between the crucial parameters of the lipase-catalyzed reactions carried out in non-aqueous systems and the yield of biodiesel synthesis. (author)

Volatilisation of aromatic hydrocarbons from soil

DEFF Research Database (Denmark)

Lindhardt, B.; Christensen, T.H.

1996-01-01

The non-steady-state fluxes of aromatic hydrocarbons were measured in the laboratory from the surface of soils contaminated with coal tar Four soil samples from a former gasworks site were used for the experiments. The fluxes were quantified for 11 selected compounds, 4 mono- and 7 polycyclic...... aromatic hydrocarbons, for a period of up to 8 or 16 days. The concentrations of the selected compounds in the soils were between 0.2 and 3,100 mu g/g. The study included the experimental determination of the distribution coefficient of the aromatic hydrocarbons between the sorbed phase and the water under...... saturated conditions. The determined distribution coefficients showed that the aromatic hydrocarbons were more strongly sorbed to the total organic carbon including the coal tar pitch - by a factor of 8 to 25 - than expected for natural organic matter. The fluxes were also estimated using an analytical...

Biotreatment of hydrocarbons from petroleum tank bottom sludges in soil slurries

International Nuclear Information System (INIS)

Ferrari, M.D.; Neirotti, E.; Albornoz, C.; Mostazo, M.R.; Cozzo, M.

1996-01-01

Biotreatment of oil wastes in aqueous slurries prepared with sandy loam soil and inoculated with selected soil cultures was evaluated. After 90 days, oil removal was 47%. Removal of each hydrocarbon class was 84% for saturates, 20% for aromatics, and 44% for asphaltenes. Resins increased by 68%. The use of a soil with a lower level of fine particles or minor organic matter content, or reinoculation with fresh culture did not improve oil elimination. Residual oil recovered from slurries was biotreated. Oil removal was 22%. Slurry-phase biotreatment showed less variability and faster oil removal than solid-phase biotreatment. (author)

Recovery of hydrocarbon oils

Energy Technology Data Exchange (ETDEWEB)

1941-02-10

A process is disclosed for recovery of hydrocarbon oils, especially lubricating oils or diesel oils, through pressure hydrogenation of distillation, extraction of hydrogenation products from coal or coaly materials or from oils such as mineral oils or tars in liquid phase by use in a reaction vessel of fixed-bed catalysts, characterized in that as starting material is employed material which has been freed of asphaltic and resinous material by hydrogenation refining, vacuum-steam distillation, treatment with hydrogen-rich hydrocarbons (hydroforming), or sulfuric acid.

Synthesis, model and stability of helically coiled carbon nanotubes

DEFF Research Database (Denmark)

Fejes, Dora; Raffai, Manuella; Hernadi, Klara

2013-01-01

. Our experiments focused on the production and development of catalysts for the synthesis of helically coiled CNTs (carbon nanotubes). The catalysts were tested in the decomposition of acetylene by CCVD (Catalytic Chemical Vapor Deposition) method. The carbon deposit was imaged by TEM (Transmission......Structural model of helically coiled carbon nanotubes is proposed. It is constructed by means of topological coordinate method. Relaxation and cohesive energy calculation are performed by molecular mechanics, using second-generation bond order potential for hydrocarbons introduced by D. W. Brenner...

Oils; lubricants; paraffin-wax compositions; hydrocarbon condensation products

Energy Technology Data Exchange (ETDEWEB)

1934-04-04

Petroleum hydrocarbons such as gasoline, kerosene, Diesel fuel oil, lubricating-oil, and paraffin wax, and like hydrocarbons such as are obtainable from shale oil and by the hydrogenation of carbonaceous materials, are improved by addition of products obtained by condensing a cyclic hydrocarbon with a saturated dihalogen derivative of an aliphatic hydrocarbon containing less than five carbon atoms. The addition of the condensation products increases the viscosity of the hydrocarbon oils specified, and is particularly useful in the case of lubricating-oils; addition of the condensation products to paraffin wax increases the transparency and adherent properties of the wax, and is useful in the manufacture of moulded articles such as candles; the products may also be used in solid lubricating-compositions.

Imaging fluid/solid interactions in hydrocarbon reservoir rocks.

Science.gov (United States)

Uwins, P J; Baker, J C; Mackinnon, I D

1993-08-01

The environmental scanning electron microscope (ESEM) has been used to image liquid hydrocarbons in sandstones and oil shales. Additionally, the fluid sensitivity of selected clay minerals in hydrocarbon reservoirs was assessed via three case studies: HCl acid sensitivity of authigenic chlorite in sandstone reservoirs, freshwater sensitivity of authigenic illite/smectite in sandstone reservoirs, and bleach sensitivity of a volcanic reservoir containing abundant secondary chlorite/corrensite. The results showed the suitability of using ESEM for imaging liquid hydrocarbon films in hydrocarbon reservoirs and the importance of simulating in situ fluid-rock interactions for hydrocarbon production programmes. In each case, results of the ESEM studies greatly enhanced prediction of reservoir/borehole reactions and, in some cases, contradicted conventional wisdom regarding the outcome of potential engineering solutions.

Catalytic synthesis of diesel from syngas: Theoretical and practical aspects

International Nuclear Information System (INIS)

Khalid, N.; Saeed, M.M.

2013-01-01

The world energy needs have been increasing tremendously resulting in the depletion of the resources of fossil fuel and increase in the prices of crude oil. To meet the required needs or decrease the dependency at least in parts, the attention of the scientists is being focused on the generation of alternate sources for the diesel fuel and other valued products. The catalytic based Fisher-Tropsch process for the generation of liquid chemicals, specially the diesel fuels from syngas is gaining attention since the products formed are of relatively low cost, high quality and environmental friendly due to low aromaticity and sulphur contents. Two main characteristics of the Fischer-Tropsch synthesis (FTS) are the unavoidable production of a wide range of hydrocarbon products (olefins, paraffins, and oxygenated products) and the liberation of large amount of heat from the highly exothermic synthesis reactions. FT synthesis products are influenced by various factors like temperature and pressure of syngas, nature of the catalyst, and the type of reactors. All these parameters are discussed by focusing special attention to the synthesis of cobalt catalyst for the production of diesel fuel. (author)

Cloning-free template DNA preparation for cell-free protein synthesis via two-step PCR using versatile primer designs with short 3'-UTR.

Science.gov (United States)

Nomoto, Mika; Tada, Yasuomi

2018-01-01

Cell-free protein synthesis (CFPS) systems largely retain the endogenous translation machinery of the host organism, making them highly applicable for proteomics analysis of diverse biological processes. However, laborious and time-consuming cloning procedures hinder progress with CFPS systems. Herein, we report the development of a rapid and efficient two-step polymerase chain reaction (PCR) method to prepare linear DNA templates for a wheat germ CFPS system. We developed a novel, effective short 3'-untranslated region (3'-UTR) sequence that facilitates translation. Application of the short 3'-UTR to two-step PCR enabled the generation of various transcription templates from the same plasmid, including fusion proteins with N- or C-terminal tags, and truncated proteins. Our method supports the cloning-free expression of target proteins using an mRNA pool from biological material. The established system is a highly versatile platform for in vitro protein synthesis using wheat germ CFPS. © 2017 Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd.

A method of refining aromatic hydrocarbons from coal chemical production

Energy Technology Data Exchange (ETDEWEB)

Zieborak, K.; Koprowski, A.; Ratajczak, W.

1979-10-01

A method is disclosed for refining aromatic hydrocarbons of coal chemical production by contact of liquid aromatic hydrocarbons and their mixtures with a strongly acid macroporous sulfocationite in the H-form at atmospheric pressure and high temperature. The method is distinguished in that the aromatic hydrocarbons and their mixtures, from which alkali compounds have already been removed, are supplied for refinement with the sulfocationite with simultaneous addition of olefin derivatives of aromatic hydrocarbons, followed by separation of pure hydrocarbons by rectification. Styrene or alpha-methylstyrene is used as the olefin derivatives of the aromatic hydrocarbons. The method is performed in several stages with addition of olefin derivatives of aromatic hydrocarbons at each stage.

Process for recovery of liquid hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Millar, J.F.; Cockshott, J.E.

1978-04-11

Methane is recovered as a gas for discharge to a pipeline from a gas stream containing methane and heavier hydrocarbons, principally ethane and propane. Separation is accomplished by condensing the heavier hydrocarbons and distilling the methane therefrom. A liquid product (LPG) comprising the heavier hydrocarbons is subsequently recovered and transferred to storage. Prior to being discharged to a pipeline, the recovered methane gas is compressed and in undergoing compression the gas is heated. The heat content of the gas is employed to reboil the refrigerant in an absorption refrigeration unit. The refrigeration unit is used to cool the LPG prior to its storage.

Worldwide overview of hydrocarbons and perspectives

International Nuclear Information System (INIS)

Tonnac, Alain de; Perves, Jean-Pierre

2013-12-01

This publication presents and comments data regarding the share of hydrocarbons in the world energy consumption, hydrocarbon trade flows, the new situation created by the emergence of shale hydrocarbons and the consequences for the world economy, and possible risks. The authors first comment the evolution of energy consumption and outline that the objectives of CO 2 and greenhouse gas emission will not be reached (these emissions increased in 2012 and in 2013). They indicate the emission situation in the USA and Japan, and notice that the objectives defined by the IEA are quite different from those defined by the EU. They analyse the evolutions by distinguishing different periods: 2005-2008 as a reference period, 2008-2012 as a period of change, and the current period as a period of flow inversion. Then, the authors propose two different scenarios of evolution of economic and energy policies. The evolution of hydrocarbon demand is commented, and the levels of reserves (oil, conventional gas, coal, nuclear fuels) are discussed. The market evolution is also discussed, not only from an economic point of view, but also in relationship with geopolitics. The authors notably outline that the energy price is different from one country to the other, discuss the issue of hydrocarbon refining, the role of CO 2 tax

Hydrocarbon-degradation by Isolate Pseudomonas lundensis UTAR FPE2

Directory of Open Access Journals (Sweden)

Adeline, S. Y. Ting

2009-01-01

Full Text Available In this study, the potential of isolate Pseudomonas lundensis UTAR FPE2 as a hydrocarbon degrader was established. Their biodegradation activity was first detected with the formation of clearing zones on Bushnell-Hass agar plates, with the largest diameter observed on plates supplemented with paraffin, followed by mineral oil and petrol. Utilization of hydrocarbon sources were again detected in broth cultures supplemented with similar hydrocarbon substrates, where the mean viable cell count recovered from hydrocarbon-supplemented broth cultures were higher than the initial inoculum except for napthalene. In both tests, the isolate showed higher degradability towards aliphatic hydrocarbon sources, and the least activity towards the aromatic hydrocarbon naphthalene. The isolate P. lundensis UTAR FPE2 (8 log10 cfu/mL also degraded crude diesel sample, with 69% degradation during the first three days. To conclude, this study suggests the potential use of this isolate for bioremediation of hydrocarbon-contaminated environments.

Synthesis of 3'-, or 5'-, or internal methacrylamido-modified oligonucleotides

Science.gov (United States)

Golova, Julia B.; Chernov, Boris K.

2010-04-27

New modifiers were synthesized for incorporation of a methacrylic function in 3'-, 5'- and internal positions of oligonucleotides during solid phase synthesis. A modifier was used for synthesis of 5'-methacrylated oligonucleotides for preparation of microarrays by a co-polymerization method.

Vinylphosphonium and 2-aminovinylphosphonium salts – preparation and applications in organic synthesis

Directory of Open Access Journals (Sweden)

Anna Kuźnik

2017-12-01

Full Text Available The main synthetic routes towards vinylphosphonium salts and their wide applications in organic synthesis are discussed in this review. Particular attention is paid to the use of these compounds as building blocks for the synthesis of carbo- and heterocyclic systems after their prior transformation into the corresponding phosphorus ylides, followed by the intramolecular Wittig reaction with various types of nucleophiles containing a carbonyl function in their structures.

Synthesis de 1-dotriacotanol

International Nuclear Information System (INIS)

Hernandez, L.; Gonzalez, J.C.

1996-01-01

In order to prepare isotopic labeled long chain aliphatic primary alcohol's, the synthesis overall yielding and chemical purity of 1-dotriacotanol were 41% and 98%, respectively. This procedure is very useful for carbon-14 and tritium labeling at Beta position of saturated fatty alcohol's

HYDROCARBONS RESERVES IN VENEZUELA

Energy Technology Data Exchange (ETDEWEB)

Gonzalez Cruz, D.J.

2007-07-01

Venezuela is an important player in the energy world, because of its hydrocarbons reserves. The process for calculating oil and associated gas reserves is described bearing in mind that 90% of the gas reserves of Venezuela are associated to oil. Likewise, an analysis is made of the oil reserves figures from 1975 to 2003. Reference is also made to inconsistencies found by international experts and the explanations offered in this respect by the Ministry of Energy and Petroleum (MENPET) and Petroleos de Venezuela (PDVSA) regarding the changes that took place in the 1980s. In turn, Hubbert's Law is explained to determine peak production of conventional oil that a reservoir or field will reach, as well as its relationship with remaining reserves. Emphasis is placed on the interest of the United Nations on this topic. The reserves of associated gas are presented along with their relationship with the different crude oils that are produced and with injected gas, as well as with respect to the possible changes that would take place in the latter if oil reserves are revised. Some recommendations are submitted so that the MENPET starts preparing the pertinent policies ruling reserves. (auth)

Potential hydrocarbon producing species of Western Ghats, Tamil Nadu, India

Energy Technology Data Exchange (ETDEWEB)

Augustus, G.D.P.S.; Jayabalan, M.; Rajarathinam, K. [Research Centre in Bombay, V.H.N.S.N. College, Virudhunagar (India); Ray, A.K. [Sardar Patel Univ., Anand (India). Dept. of Chemistry; Seiler, G.J. [USDA, ARS, Northern Crop Science Lab., Fargo, ND (United States)

2002-09-01

The decline in the world supplies of hydrocarbons has led to the search for alternate sources of fuel and chemicals. Plant species are potential sources of hydrocarbons. Large-scale screening of plants growing in the Western Ghats, Tamil Nadu, India was conducted to assess the hydrocarbon production and the type of isoprene compound(s) present. Three species contained more than 3% hydrocarbon. Sarcostemma brevistigma had the highest concentration of hydrocarbon with 3.6%. Seven species contained more than 2% of hydrocarbons among the plant species screened. The hydrocarbon fraction of Ficus elastica (leaf) had a gross heat value of 9834 cal/g (41.17 MJ/kg), which is close to the caloric value of fuel oil. Six hydrocarbon fractions contained gross heat values of more than 9000 cal/g (37.68 MJ/kg). Of the 13 species hydrocarbon fraction analysed, seven species contained cis-polyisoprene compounds, while two species contained trans-polyisoprenes. Cis and trans polyisoprenes are potential alternative energy sources for fuel and/or as industrial raw materials. (author)

AD1995: NW Europe's hydrocarbon industry

International Nuclear Information System (INIS)

Glennie, K.; Hurst, A.

1996-01-01

This volume concerns itself with wide-ranging aspects of the upstream hydro-carbon industry over the whole of NW Europe. As such, the book contrasts with many thematic volumes by presenting a broad range of topics side-by-side. One section of the book looks back at the history of geological exploration and production, and provides an overview of hydrocarbon exploration across NW Europe. Another section covers the state of the art in hydrocarbon exploration and production. This includes an update on computer-based basin modelling overpressure systems, innovations in reservoir engineering and reserve estimation, 3D seismic and the geochemical aspects of secondary migration. The final section of the book takes a look into the future. This covers the remaining hydrocarbon resources of the North Sea, managing risk in oil field development, oil field economics, and pollution and the environment. It is the editors' hope that several key areas of NW Europe's upstream oil industry have been usefully summarized in the volume. (Author)

Enrichment of light hydrocarbon mixture

Science.gov (United States)

Yang,; Dali, [Los Alamos, NM; Devlin, David [Santa Fe, NM; Barbero, Robert S [Santa Cruz, NM; Carrera, Martin E [Naperville, IL; Colling, Craig W [Warrenville, IL

2010-08-10

Light hydrocarbon enrichment is accomplished using a vertically oriented distillation column having a plurality of vertically oriented, nonselective micro/mesoporous hollow fibers. Vapor having, for example, both propylene and propane is sent upward through the distillation column in between the hollow fibers. Vapor exits neat the top of the column and is condensed to form a liquid phase that is directed back downward through the lumen of the hollow fibers. As vapor continues to ascend and liquid continues to countercurrently descend, the liquid at the bottom of the column becomes enriched in a higher boiling point, light hydrocarbon (propane, for example) and the vapor at the top becomes enriched in a lower boiling point light hydrocarbon (propylene, for example). The hollow fiber becomes wetted with liquid during the process.

Purifying hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Dunstan, A E

1918-06-03

Ligroin, kerosene, and other distillates from petroleum and shale oil, are purified by treatment with a solution of a hypochlorite containing an excess of alkali. The hydrocarbon may be poured into brine, the mixture stirred, and an electric current passed through. Heat may be applied.

One-pot and efficient synthesis of triazolo[1,2-a]indazole-triones via reaction of arylaldehydes with urazole and dimedone catalyzed by silica nanoparticles prepared from rice husk.

Science.gov (United States)

Hamidian, Hooshang; Fozooni, Samieh; Hassankhani, Asadollah; Mohammadi, Sayed Zia

2011-10-26

A novel synthesis of triazolo[1,2-a]indazole-1,3,8-trione derivatives by reaction of urazole, dimedone and aromatic aldehydes under conventional heating and microwave irradiation and solvent-free conditions using silica nanoparticles prepared from rice husk ash as catalyst is described. The new method features high yields, multicomponent reactions and environmental friendliness.

Culture-dependent characterization of hydrocarbon utilizing bacteria ...

African Journals Online (AJOL)

EARNEST

Hydrocarbons interact with the environment and micro- organisms determining the .... it is pertinent to study the community dynamics of hydrocarbon degrading bacteria ... Chikere CB (2013). Application of molecular microbiology techniques in.

Identifying future directions for subsurface hydrocarbon migration research

Science.gov (United States)

Leifer, I.; Clark, J. F.; Luyendyk, B.; Valentine, D.

Subsurface hydrocarbon migration is important for understanding the input and impacts of natural hydrocarbon seepage on the environment. Great uncertainties remain in most aspects of hydrocarbon migration, including some basic mechanisms of this four-phase flow of tar, oil, water, and gas through the complex fracture-network geometry particularly since the phases span a wide range of properties. Academic, government, and industry representatives recently attended a workshop to identify the areas of greatest need for future research in shallow hydrocarbon migration.Novel approaches such as studying temporal and spatial seepage variations and analogous geofluid systems (e.g., geysers and trickle beds) allow deductions of subsurface processes and structures that remain largely unclear. Unique complexities exist in hydrocarbon migration due to its multiphase flow and complex geometry, including in-situ biological weathering. Furthermore, many aspects of the role of hydrocarbons (positive and negative) in the environment are poorly understood, including how they enter the food chain (respiration, consumption, etc.) and “percolate” to higher trophic levels. But understanding these ecological impacts requires knowledge of the emissions' temporal and spatial variability and trajectories.

Process for preparation of a zeolite catalyst and its usage for the catalytic conversion of hydrocarbons. Verfahren zur Herstellung eines Zeolith-Katalysators und Verwendung des mittels dieses Verfahrens hergestellten Katalysators zur katalytischen Umwandlung von Kohlenwasserstoffen

Energy Technology Data Exchange (ETDEWEB)

Kuijpers, K.G.Y.A.S.; Nanne, J M

1972-08-25

The selectivity of a zeolite catalyst for hydrocracking of linear hydrocarbons is markedly improved by a controlled calcining during preparation. Several active components are deposited on the zeolite so that a catalyst composition of 0.7 to 1.2 Na/sub 2/OxAl/sub 2/O/sub 3/x4.7 to 5.3 SiO/sub 2/xx H/sub 2/O with x = 3 to 9 is formed. At least during the first calcining step at end temperatures of 400 to 550/sup 0/C a fixed partial pressure of water vapor is maintained in the atmosphere around the material in dependence of its temperature.

33 CFR 157.166 - Hydrocarbon emissions.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Hydrocarbon emissions. 157.166 Section 157.166 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED... Crude Oil Washing (COW) System on Tank Vessels Cow Operations § 157.166 Hydrocarbon emissions. If the...

Hydrocarbons in the Hauptsalz formation of the Gorleben salt dome. Content, distribution and origin

Energy Technology Data Exchange (ETDEWEB)

Pusch, Maximilian; Hammer, Joerg; Ostertag-Henning, Christian [Federal Institute for Geosciences and Natural Resources (BGR), Hannover (Germany)

2015-07-01

boundaries of halite crystals, on the surfaces and knuckles or inside of micro capillary tubes of anhydrite crystals and anhydrite clusters, in newly formed micro cracks due to drilling respectively preparational works or rarely in micro-porous parts of the Hauptsalz. In order to get additional information about the origin of hydrocarbons detected in the Gorleben Hauptsalz organic geochemical analyses of potential source rocks in the vicinity like the Stassfurt Carbonate (z2SK) have been provided. These analyses revealed that the level of maturity of hydrocarbons in the Gorleben Hauptsalz correspond to 0,8 to 1,2% vitrinite-reflection-equivalent for the oil, similar to the organic-petrographical data of Stassfurt Carbonate and Copper schist in the periphery of the Gorleben salt dome (Gerling et al. 2002; Senglaub 2001; Cramer 2005). The analyses of biomarkers (esp. triterpenoid biomarkers) detected in the hydrocarbon mixtures from the Hauptsalz point to the Stassfurt Carbonate as source rocks of most of the hydrocarbons.

Hydrocarbon removal with constructed wetlands

OpenAIRE

Eke, Paul Emeka

2008-01-01

Wetlands have long played a significant role as natural purification systems, and have been effectively used to treat domestic, agricultural and industrial wastewater. However, very little is known about the biochemical processes involved, and the use of constructed treatment wetlands in the removal of petroleum aromatic hydrocarbons from produced and/or processed water. Wastewaters from the oil industry contain aromatic hydrocarbons such as benzene, toluene, ethylbenzene and x...

Solvent-Free Synthesis of Quaternary Metal Sulfide Nanoparticles Derived from Thiourea

KAUST Repository

Bhunia, Manas Kumar

2017-08-09

The synthesis of metal sulfide (MS) materials with sizes in the sub-10 nm regime often requires capping agents with long hydrocarbon chains that affect their structures and properties. Herein, this study presents a molten-state synthesis method for a series of transition-MS nanoparticles using thiourea as a reactive precursor without capping agents. This study also reports the synthesis of MS with single metals (Fe, Co, Ni, Cu, and Zn) and quaternary CuGa2In3S8 using the same synthesis protocol. Thiourea first melts to form a molten-state condition to serve as the reaction medium at a relatively low temperature (<200 °C), followed by its thermal decomposition to induce a reaction with the metal precursor to form different MS. This synthesis protocol, owing to its dynamic characteristics, involves the formation of a variety of organic carbon nitride polymeric complexes around the MS particles. Dynamic nuclear polarization surface-enhanced nuclear magnetic resonance spectroscopy is effective to identify the polymeric compositions and structures as well as their interactions with the MS. These results provided thorough structural descriptions of the MS nanoparticles surrounded by the carbon nitride species derived from thiourea, which may find various applications, including photocatalytic water splitting.

Biochemical and Physical Characterization of Petroleum Hydrocarbon Contaminated Soils in Tehran

Directory of Open Access Journals (Sweden)

Mehrdad Cheraghi

2015-07-01

Full Text Available    Contamination of soil was investigated in this study from the Tehran Oil refining Co. of Iran. Fifteen soil samples were collected at several points in the Azimabad, 15 km south of Tehran City, Iran. Samples were collected at depths of 0–30 cm. Control sampleswere prepared to determinebackgroundlevels ofsoil contaminationwithpetroleumhydrocarbonsfor comparison with contaminatedsites. Total petroleum hydrocarbon (TPH and poly-aromatic hydrocarbons (PAH concentrations varied from 101334.0–101367.1 and 25321.1–25876.6 mg kg-1 respectively. The results elevated levels of TPH and PAH contents when compared with the control sample. Soil acidity (low pH of 5.3–5.9 and low electrical conductivity provided evidence of reduced metabolic activities on the affected site.Microbialgrowthrates for bacteria and fungi expressed as colony forming units were 2.62×109 and 4.14×106CFU/g soil, respectively for the contaminated and 5.76×109 and 6.83×106CFU/g soil, for the control treatments respectively. These drastic changes can have impact on the nutrient cycle and prevents the absorption of nutrients by plant root sand lead to a reduction in yield. 

Facile synthesis of Ag nanocubes and Au nanocages.

Science.gov (United States)

Skrabalak, Sara E; Au, Leslie; Li, Xingde; Xia, Younan

2007-01-01

This protocol describes a method for the synthesis of Ag nanocubes and their subsequent conversion into Au nanocages via the galvanic replacement reaction. The Ag nanocubes are prepared by a rapid (reaction time nanocubes. With this method, Ag nanocubes can be prepared and isolated for use within approximately 3 h. The Ag nanocubes can then serve as sacrificial templates for the preparation of Au nanocages, with a method for their preparation also described herein. The procedure for Au nanocage preparation and isolation requires approximately 5 h.

Sample preparation of sewage sludge and soil samples for the determination of polycyclic aromatic hydrocarbons based on one-pot microwave-assisted saponification and extraction

Energy Technology Data Exchange (ETDEWEB)

Pena, M.T.; Pensado, Luis; Casais, M.C.; Mejuto, M.C.; Cela, Rafael [Universidad de Santiago de Compostela, Dpto. Quimica Analitica, Nutricion y Bromatologia. Instituto de Investigacion y Analisis Alimentario, Santiago de Compostela (Spain)

2007-04-15

A microwave-assisted sample preparation (MASP) procedure was developed for the analysis of polycyclic aromatic hydrocarbons (PAHs) in sewage sludge and soil samples. The procedure involved the simultaneous microwave-assisted extraction of PAHs with n-hexane and the hydrolysis of samples with methanolic potassium hydroxide. Because of the complex nature of the samples, the extracts were submitted to further cleaning with silica and Florisil solid-phase extraction cartridges connected in series. Naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[e]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenz[a,h]anthracene, benzo[g,h,i]perylene, and indeno[1,2,3-cd]pyrene, were considered in the study. Quantification limits obtained for all of these compounds (between 0.4 and 14.8 {mu}g kg{sup -1} dry mass) were well below of the limits recommended in the USA and EU. Overall recovery values ranged from 60 to 100%, with most losses being due to evaporation in the solvent exchange stages of the procedure, although excellent extraction recoveries were obtained. Validation of the accuracy was carried out with BCR-088 (sewage sludge) and BCR-524 (contaminated industrial soil) reference materials. (orig.)

Sample preparation of sewage sludge and soil samples for the determination of polycyclic aromatic hydrocarbons based on one-pot microwave-assisted saponification and extraction.

Science.gov (United States)

Pena, M Teresa; Pensado, Luis; Casais, M Carmen; Mejuto, M Carmen; Cela, Rafael

2007-04-01

A microwave-assisted sample preparation (MASP) procedure was developed for the analysis of polycyclic aromatic hydrocarbons (PAHs) in sewage sludge and soil samples. The procedure involved the simultaneous microwave-assisted extraction of PAHs with n-hexane and the hydrolysis of samples with methanolic potassium hydroxide. Because of the complex nature of the samples, the extracts were submitted to further cleaning with silica and Florisil solid-phase extraction cartridges connected in series. Naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[e]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenz[a,h]anthracene, benzo[g,h,i]perylene, and indeno[1,2,3-cd]pyrene, were considered in the study. Quantification limits obtained for all of these compounds (between 0.4 and 14.8 microg kg(-1) dry mass) were well below of the limits recommended in the USA and EU. Overall recovery values ranged from 60 to 100%, with most losses being due to evaporation in the solvent exchange stages of the procedure, although excellent extraction recoveries were obtained. Validation of the accuracy was carried out with BCR-088 (sewage sludge) and BCR-524 (contaminated industrial soil) reference materials.

Preparation of 1-bromoheptacosane

International Nuclear Information System (INIS)

Hernandez, L.; Hernandez, A.; Gonzalez, J.C.

1996-01-01

Alkybromides are ones of the main organic precursors for fatty acids and alcohols labelling with Carbon 1-14. In this work the preparation of 1-bromoheptacosane by bromodescarboxylation of 1-octacosanoic acid is described. The synthesis yielded 80.5% of final product and more than 97% of chemical purity. Clean-up procedure modifications and spectral data bromoheptacosane are also reported

Polycyclic’ Aromatic Hydrocarbon Induced Intracellular Signaling and Lymphocyte Apoptosis

DEFF Research Database (Denmark)

Schneider, Alexander M.

The aryl hydrocarbon (dioxin) receptor (AhR) is a transcription factor possessing high affinity to potent environmental pollutants, polycyclic aromatic hydrocarbons (PAH) and related halogenated hydrocarbons (e.g. dioxins). Numerous research attribute toxicity of these compounds to the receptor...

One-Pot and Efficient Synthesis of Triazolo[1,2-a]indazole-triones via Reaction of Arylaldehydes with Urazole and Dimedone Catalyzed by Silica Nanoparticles Prepared from Rice Husk

Directory of Open Access Journals (Sweden)

Asadollah Hassankhani

2011-10-01

Full Text Available A novel synthesis of triazolo[1,2-a]indazole-1,3,8-trione derivatives by reaction of urazole, dimedone and aromatic aldehydes under conventional heating and microwave irradiation and solvent-free conditions using silica nanoparticles prepared from rice husk ash as catalyst is described. The new method features high yields, multicomponent reactions and environmental friendliness.

Cermet materials prepared by combustion synthesis and metal infiltration

Science.gov (United States)

Holt, Joseph B.; Dunmead, Stephen D.; Halverson, Danny C.; Landingham, Richard L.

1991-01-01

Ceramic-metal composites (cermets) are made by a combination of self-propagating high temperature combustion synthesis and molten metal infiltration. Solid-gas, solid-solid and solid-liquid reactions of a powder compact produce a porous ceramic body which is infiltrated by molten metal to produce a composite body of higher density. AlN-Al and many other materials can be produced.

Pt based PEMFC catalysts prepared from colloidal particle suspensions--a toolbox for model studies.

Science.gov (United States)

Speder, Jozsef; Altmann, Lena; Roefzaad, Melanie; Bäumer, Marcus; Kirkensgaard, Jacob J K; Mortensen, Kell; Arenz, Matthias

2013-03-14

A colloidal synthesis approach is presented that allows systematic studies of the properties of supported proton exchange membrane fuel cell (PEMFC) catalysts. The applied synthesis route is based on the preparation of monodisperse nanoparticles in the absence of strong binding organic stabilizing agents. No temperature post-treatment of the catalyst is required rendering the synthesis route ideally suitable for comparative studies. We report work concerning a series of catalysts based on the same colloidal Pt nanoparticle (NP) suspension, but with different high surface area (HSA) carbon supports. It is shown that for the prepared catalysts the carbon support has no catalytic co-function, but carbon pre-treatment leads to enhanced sticking of the Pt NPs on the support. An unwanted side effect, however, is NP agglomeration during synthesis. By contrast, enhanced NP sticking without agglomeration can be accomplished by the addition of an ionomer to the NP suspension. The catalytic activity of the prepared catalysts for the oxygen reduction reaction is comparable to industrial catalysts and no influence of the particle size is found in the range of 2-5 nm.

Method for production of unsaturated gaseous hydrocarbons, particularly ethylene, and of aromatic hydrocarbons, adapted as motor fuels

Energy Technology Data Exchange (ETDEWEB)

1952-10-24

A method is described for the production of unsaturated gaseous hydrocarbons, in particular of ethylene, and of aromatic hydrocarbons from hydrocarbon oils or from fractions of the same, characterized by the fact that the raw materials are brought into contact with porous, inert substances in the form of fine distribution or of pieces at a temperature of above 500 and in particular from 600 to about 700/sup 0/C and with a traversing speed of from 0.3 up to about 3.0 volumetric parts, preferably up to 1.5 volumetric parts of raw material per volumetric part of the chamber and per hour.

Synthesis of magnetic polymeric microspheres

Energy Technology Data Exchange (ETDEWEB)

Gervald, A Yu; Gritskova, Inessa A; Prokopov, Nikolai I [M.V. Lomonosov Moscow State Academy of Fine Chemical Technology, Moscow (Russian Federation)

2010-05-13

The key types of magnetic polymeric microspheres are considered. Methods of synthesis of different types of magnetic nanoparticles and of preparation of stable magnetic fluids on their basis are outlined. The overview of the methods for the manufacture of magnetic polymeric microspheres is presented. The effect of the synthesis conditions on the characteristics of magnetic polymeric microspheres such as the diameter and the particle size distribution and the content of magnetic material is discussed by particular examples. The application fields of magnetic polymeric microspheres are briefly surveyed.

Synthesis of magnetic polymeric microspheres

International Nuclear Information System (INIS)

Gervald, A Yu; Gritskova, Inessa A; Prokopov, Nikolai I

2010-01-01

The key types of magnetic polymeric microspheres are considered. Methods of synthesis of different types of magnetic nanoparticles and of preparation of stable magnetic fluids on their basis are outlined. The overview of the methods for the manufacture of magnetic polymeric microspheres is presented. The effect of the synthesis conditions on the characteristics of magnetic polymeric microspheres such as the diameter and the particle size distribution and the content of magnetic material is discussed by particular examples. The application fields of magnetic polymeric microspheres are briefly surveyed.

Synthesis of allocolchicinoids: a 50 year journey

International Nuclear Information System (INIS)

Sitnikov, N S; Fedorov, A Yu

2013-01-01

Published data on the stereo- and enantioselective synthesis of allocolchicinoids, which are of interest as antitumour agents, are summarized. The stereochemistry of these compounds is described. Two key approaches to their preparation are considered, namely, the synthesis from natural colchicine and total synthesis from commercially available reagents. Various total syntheses of N-acetylcolchicinol are performed using biaryl oxidative and reductive coupling, cyclopropanation–ring expansion and Nicholas reaction. The synthetic routes to allocolchicine are based on Diels–Alder cycloaddition, combination of metathesis and Diels–Alder reaction and direct catalytic CH-arylation. Analogues of the colchicine site ligands incorporating heteroaromatic rings are briefly considered; their structural features and methods of synthesis are discussed. The bibliography includes 144 references.

Organic Analysis of Catalytic Fischer-Tropsch Synthesis Products and Ordinary Chondrite Meteorites by Stepwise Pyrolysis-GCMS: Organics in the Early Solar Nebula

Science.gov (United States)

Locke, Darren R.; Yazzie, Cyriah A.; Burton, Aaron S.; Niles, Paul B.; Johnson, Natasha M.

2014-01-01

Abiotic generation of complex organic compounds, in the early solar nebula that formed our solar system, is hypothesized by some to occur via Fischer-Tropsch (FT) synthesis. In its simplest form, FT synthesis involves the low temperature (300degC) produces FT products that include lesser amounts of n-alkanes and greater alkene, alcohol, and polycyclic aromatic hydrocarbon (PAH) compounds. We have begun to experimentally investigate FT synthesis in the context of abiotic generation of organic compounds in the early solar nebula. It is generally thought that the early solar nebula included abundant hydrogen and carbon monoxide gases and nano-particulate matter such as iron and metal silicates that could have catalyzed the FT reaction. The effect of FT reaction temperature, catalyst type, and experiment duration on the resulting products is being investigated. These solid organic products are analyzed by thermal-stepwise pyrolysis-GCMS and yield the types and distribution of hydrocarbon compounds released as a function of temperature. We show how the FT products vary by reaction temperature, catalyst type, and experimental duration and compare these products to organic compounds found to be indigenous to ordinary chondrite meteorites. We hypothesize that the origin of organics in some chondritic meteorites, that represent an aggregation of materials from the early solar system, may at least in part be from FT synthesis that occurred in the early solar nebula.

Synthesis of inorganic materials in a supercritical carbon dioxide medium. Application to ceramic cross-flow filtration membranes preparation

International Nuclear Information System (INIS)

Papet, Sebastien

2000-01-01

Membrane separations, using cross-flow mineral ceramic membranes, allows fractionation of aqueous solutions due to the molecular sieve effect and electrostatic charges. To obtain a high selectivity, preparation of new selective ceramic membranes is necessary. We propose in this document two different routes to prepare such cross-flow tubular mineral membranes. In the first exposed method, a ceramic material is used, titanium dioxide, synthesized in supercritical carbon dioxide by the hydrolysis of an organometallic precursor of the oxide. The influence of operating parameters is similar to what is observed during a liquid-phase synthesis (sol-gel process), and leads us to control the size and texture of the prepared particles. This material is then used to prepare mineral membrane with a compressed layer process. The particles are mixed with organic components to form a liquid suspension. A layer is then deposited on the internal surface of a tubular porous support by slip-casting. The layer is then dried and compressed on the support before sintering. The obtained membranes arc in the ultrafiltration range. A second process has been developed in this work. It consists on the hydrolysis, in a supercritical CO 2 medium, of a precursor of titanium dioxide infiltrated into the support. The obtained material is then both deposited on the support but also infiltrated into the porosity. This new method leads to obtain ultrafiltration membranes that retain molecules which molecular weight is round 4000 g.mol -1 . Furthermore, we studied mass transfer mechanisms in cross-flow filtration of aqueous solutions. An electrostatic model, based on generalized Nernst-Planck equation that takes into account electrostatic interactions between solutes and the ceramic material, lead us to obtain a good correlation between experimental results and the numerical simulation. (author) [fr

Catalytic conversion of alcohols to hydrocarbons with low benzene content

Energy Technology Data Exchange (ETDEWEB)

Narula, Chaitanya K.; Davison, Brian H.; Keller, Martin

2016-03-08

A method for converting an alcohol to a hydrocarbon fraction having a lowered benzene content, the method comprising: converting said alcohol to a hydrocarbon fraction by contacting said alcohol, under conditions suitable for converting said alcohol to said hydrocarbon fraction, with a metal-loaded zeolite catalyst catalytically active for converting said alcohol to said hydrocarbon fraction, and contacting said hydrocarbon fraction with a benzene alkylation catalyst, under conditions suitable for alkylating benzene, to form alkylated benzene product in said hydrocarbon fraction. Also described is a catalyst composition useful in the method, comprising a mixture of (i) a metal-loaded zeolite catalyst catalytically active for converting said alcohol to said hydrocarbon, and (ii) a benzene alkylation catalyst, in which (i) and (ii) may be in a mixed or separated state. A reactor for housing the catalyst and conducting the reaction is also described.

Catalytic conversion of alcohols to hydrocarbons with low benzene content

Energy Technology Data Exchange (ETDEWEB)

Narula, Chaitanya K.; Davison, Brian H.; Keller, Martin

2016-09-06

A method for converting an alcohol to a hydrocarbon fraction having a lowered benzene content, the method comprising: converting said alcohol to a hydrocarbon fraction by contacting said alcohol, under conditions suitable for converting said alcohol to said hydrocarbon fraction, with a metal-loaded zeolite catalyst catalytically active for converting said alcohol to said hydrocarbon fraction, and contacting said hydrocarbon fraction with a benzene alkylation catalyst, under conditions suitable for alkylating benzene, to form alkylated benzene product in said hydrocarbon fraction. Also described is a catalyst composition useful in the method, comprising a mixture of (i) a metal-loaded zeolite catalyst catalytically active for converting said alcohol to said hydrocarbon, and (ii) a benzene alkylation catalyst, in which (i) and (ii) may be in a mixed or separated state. A reactor for housing the catalyst and conducting the reaction is also described.

Natural radioactivity in mining and hydrocarbon extraction industry. Vol. 1

Energy Technology Data Exchange (ETDEWEB)

Testa, C; Desideri, D; Meli, M A; Roselli, C [General Chemistry Institute, Urbino University, 61029 Urbino, (Italy)

1996-03-01

Water and soil natural radioactivity is a well known phenomenon which can produced by variable concentrations of uranium and thorium series radionuclides. Generally, the relevant radiological hazard is not important; however, some radiation protection problems can occur in particular industrial processes involving the treatment of large quantities of materials. In this case a high concentration of radioactive substance (NORM: nationally occurring radioactive materials) can be found at special points of the plant, in the manufacture by-products and in the waters. Sometimes the national radioactivity concentration can be so high to raise radiation protection problems which can be assimilated in a sense to the ones faced in the presence, handling, and disposal of non-sealed radioactive sources. In this paper the following mining and hydrocarbon extraction plants were particularly taken into account: (a) industries using zircon sands to produce refractory and ceramic materials; (b) phosphorites manufacture to prepare phosphoric acids, plasters and fertilizers (c) hydrocarbon extraction and treatment processes where formations of low specific activity (L.S.A.) scales and sludges are produced. The relevant results and the possible radiation protection risks for the professional exposed staff will be reported. A special emphasis will be given to some african phosphorites (boucraa, togo, morocco), and L.S.A. scales (tunisia, congo, Egypt). 4 figs., 5 tabs.

Natural radioactivity in mining and hydrocarbon extraction industry. Vol. 1

International Nuclear Information System (INIS)

Testa, C.; Desideri, D.; Meli, M.A.; Roselli, C.

1996-01-01

Water and soil natural radioactivity is a well known phenomenon which can produced by variable concentrations of uranium and thorium series radionuclides. Generally, the relevant radiological hazard is not important; however, some radiation protection problems can occur in particular industrial processes involving the treatment of large quantities of materials. In this case a high concentration of radioactive substance (NORM: nationally occurring radioactive materials) can be found at special points of the plant, in the manufacture by-products and in the waters. Sometimes the national radioactivity concentration can be so high to raise radiation protection problems which can be assimilated in a sense to the ones faced in the presence, handling, and disposal of non-sealed radioactive sources. In this paper the following mining and hydrocarbon extraction plants were particularly taken into account: a) industries using zircon sands to produce refractory and ceramic materials; b) phosphorites manufacture to prepare phosphoric acids, plasters and fertilizers c) hydrocarbon extraction and treatment processes where formations of low specific activity (L.S.A.) scales and sludges are produced. The relevant results and the possible radiation protection risks for the professional exposed staff will be reported. A special emphasis will be given to some african phosphorites (boucraa, togo, morocco), and L.S.A. scales (tunisia, congo, Egypt). 4 figs., 5 tabs

Methods for reformation of gaseous hydrocarbons using electrical discharge

KAUST Repository

Cha, Min Suk

2017-02-16

Methods for the reformation of gaseous hydrocarbons are provided. The methods can include forming a bubble containing the gaseous hydrocarbon in a liquid. The bubble can be generated to pass in a gap between a pair of electrodes, whereby an electrical discharge is generated in the bubble at the gap between the electrodes. The electrodes can be a metal or metal alloy with a high melting point so they can sustain high voltages of up to about 200 kilovolts. The gaseous hydrocarbon can be combined with an additive gas such as molecular oxygen or carbon dioxide. The reformation of the gaseous hydrocarbon can produce mixtures containing one or more of H2, CO, H2O, CO2, and a lower hydrocarbon such as ethane or ethylene. The reformation of the gaseous hydrocarbon can produce low amounts of CO2 and H2O, e.g. about 15 mol-% or less.

Methods for reformation of gaseous hydrocarbons using electrical discharge

KAUST Repository

Cha, Min; Zhang, Xuming

2017-01-01

Methods for the reformation of gaseous hydrocarbons are provided. The methods can include forming a bubble containing the gaseous hydrocarbon in a liquid. The bubble can be generated to pass in a gap between a pair of electrodes, whereby an electrical discharge is generated in the bubble at the gap between the electrodes. The electrodes can be a metal or metal alloy with a high melting point so they can sustain high voltages of up to about 200 kilovolts. The gaseous hydrocarbon can be combined with an additive gas such as molecular oxygen or carbon dioxide. The reformation of the gaseous hydrocarbon can produce mixtures containing one or more of H2, CO, H2O, CO2, and a lower hydrocarbon such as ethane or ethylene. The reformation of the gaseous hydrocarbon can produce low amounts of CO2 and H2O, e.g. about 15 mol-% or less.

Toxicity of petroleum hydrocarbon distillates to soil organisms.

Science.gov (United States)

Cermak, Janet H; Stephenson, Gladys L; Birkholz, Detlef; Wang, Zhendi; Dixon, D George

2010-12-01

Canadian standards for petroleum hydrocarbons in soil are based on four distillate ranges (F1, C6-C10; F2, >C10-C16; F3, >C16-C34; and F4, >C34). Concerns have arisen that the ecological soil contact standards for F3 may be overly conservative. Oil distillates were prepared and characterized, and the toxicity of F3 and two subfractions, F3a (>C16-C23) and F3b (>C23-C34), to earthworms (Eisenia andrei), springtails (Orthonychiurus folsomi), and northern wheatgrass (Elymus lanceolatus), as well as the toxicity of F2 to earthworms, was determined. Clean soil was spiked with individual distillates and measured concentrations were determined for select tests. Results agree with previous studies with these distillates. Reported toxicities of crude and petroleum products to invertebrates were generally comparable to that of F3 and F3a. The decreasing order of toxicity was F3a > F3 > F3b with invertebrates, and F3a > F3b > F3 with plants. The toxicities of F3a and F3b were not sufficiently different to recommend regulating hydrocarbons based on these distillate ranges. The results also suggest that test durations may be insufficient for determining toxicity of higher distillate ranges, and that the selection of species and endpoints may significantly affect interpretation of toxicity test results. Copyright © 2010 SETAC.

Bioremediation of Petroleum Hydrocarbon Contaminated Sites

Energy Technology Data Exchange (ETDEWEB)

Fallgren, Paul

2009-03-30

Bioremediation has been widely applied in the restoration of petroleum hydrocarbon-contaminated. Parameters that may affect the rate and efficiency of biodegradation include temperature, moisture, salinity, nutrient availability, microbial species, and type and concentration of contaminants. Other factors can also affect the success of the bioremediation treatment of contaminants, such as climatic conditions, soil type, soil permeability, contaminant distribution and concentration, and drainage. Western Research Institute in conjunction with TechLink Environmental, Inc. and the U.S. Department of Energy conducted laboratory studies to evaluate major parameters that contribute to the bioremediation of petroleum-contaminated drill cuttings using land farming and to develop a biotreatment cell to expedite biodegradation of hydrocarbons. Physical characteristics such as soil texture, hydraulic conductivity, and water retention were determined for the petroleum hydrocarbon contaminated soil. Soil texture was determined to be loamy sand to sand, and high hydraulic conductivity and low water retention was observed. Temperature appeared to have the greatest influence on biodegradation rates where high temperatures (>50 C) favored biodegradation. High nitrogen content in the form of ammonium enhanced biodegradation as well did the presence of water near field water holding capacity. Urea was not a good source of nitrogen and has detrimental effects for bioremediation for this site soil. Artificial sea water had little effect on biodegradation rates, but biodegradation rates decreased after increasing the concentrations of salts. Biotreatment cell (biocell) tests demonstrated hydrocarbon biodegradation can be enhanced substantially when utilizing a leachate recirculation design where a 72% reduction of hydrocarbon concentration was observed with a 72-h period at a treatment temperature of 50 C. Overall, this study demonstrates the investigation of the effects of

Synthesis and Characterization of Nanostructured ZnO Thick Film Gas Sensors Prepared by Screen Printing Method

Directory of Open Access Journals (Sweden)

R. Y. BORSE

2010-12-01

Full Text Available Nanosized ZnO was prepared by self propagating solution combustion synthesis method. The synthesized ZnO thick films were deposited on alumina substrate by using standard screen printing technique and fired at 700 0C. The films were characterized by X-ray diffractometer (XRD, Scanning Electron Microscopy (SEM and energy dispersive analysis of X-ray (EDAX. The electrical behaviors of ZnO thick films were investigated. From XRD spectra it is revealed that ZnO films are polycrystalline in nature. The average grain size of 87.44 nm has been estimated for the film fired at 700 0C using Scherrer’s formula. EDAX clearly shows the peaks corresponding to Zn and O element which confirms the successful growth of ZnO films. Gas sensing study for these samples shows high sensitivity and selectivity towards NO2 at all operating temperatures. The resistivity, TCR and activation energy of the ZnO films have been evaluated and discussed.

Degradation of petroleum hydrocarbons in a laboratory aquifer column

International Nuclear Information System (INIS)

Billowits, M.; Whyte, L.; Greer, C.; Ramsay, J.

1998-01-01

One of the primary mechanisms for eliminating hydrocarbon pollutants from the environment is degradation of hydrocarbons by indigenous microorganisms. This report describes a study in which samples from a petroleum polluted shallow aquifer in the Yukon were used which contained a hundred times greater concentration of psychrotropic bacteria than mesophilic bacteria. Results showed a maximum degradation of 47 per cent of the total petroleum hydrocarbon in columns which simulated the aquifer conditions and to which nutrients were added. It was concluded that although in this case bioaugmentation of the columns with a psychrotropic hydrocarbon-degrading consortium increased microbial numbers, total petroleum hydrocarbon degradation was not much greater than could be achieved by remediation with nutrients alone

Hydrocarbons in Argentina: networks, territories, integration

International Nuclear Information System (INIS)

Carrizo, S.C.

2003-12-01

Argentinean hydrocarbons networks have lived a huge reorganizing the structure, after the State reform in the 90's. Activities deregulation and the privatization of YPF and Gas del Estado forced the sector re-concentration, since then dominated by foreign companies, leaded by Repsol YPF. The hydrocarbons federalization contributed to the weakening and un-capitalization loss of wealth of the State. These changes resulted in an increase of the hydrocarbons production allowing to achieve the self-supply. Nevertheless, the expansion of internal networks has not been large enough to ensure the coverage of new requirements. Besides, several infrastructures have been built up to join external markets. National networks are connected to those of near neighboring countries. This integration is an opportunity for the 'South Cone' countries to enhance their potentials. In the country, hydrocarbons territories undergo the reorganizing the structure effects (unemployment, loss of territorial identity, etc). With many difficulties and very different possibilities, those territories, like Comodoro Rivadavia, Ensenada et and Bahia Blanca, look for their re-invention. (author)

Sol – Gel synthesis and characterization of magnesium peroxide nanoparticles

International Nuclear Information System (INIS)

Jaison, J; Chan, Y S; Ashok raja, C; Balakumar, S

2015-01-01

Magnesium peroxide is an excellent source of oxygen in agriculture applications, for instance it is used in waste management as a material for soil bioremediation to remove contaminants from polluted underground water, biological wastes treatment to break down hydrocarbon, etc. In the present study, sol-gel synthesis of magnesium peroxide (MgO 2 ) nanoparticles is reported. Magnesium peroxide is odourless; fine peroxide which releases oxygen when reacts with water. During the sol-gel synthesis, the magnesium malonate intermediate is formed which was then calcinated to obtain MgO 2 nanoparticles. The synthesized nanoparticles were characterized using Thermo gravimetric -Differential Thermal Analysis (TG- DTA), X-Ray Diffraction studies (XRD) and High Resolution Transmission Electron Microscope (HRTEM). Our study provides a clear insight that the formation of magnesium malonate during the synthesis was due to the reaction between magnesium acetate, oxalic acid and ethanol. In our study, we can conclude that the calcination temperature has a strong influence on particle size, morphology, monodispersity and the chemistry of the particles. (paper)

Application of Fischer–Tropsch Synthesis in Biomass to Liquid Conversion

Directory of Open Access Journals (Sweden)

Yongwu Lu

2012-06-01

Full Text Available Fischer–Tropsch synthesis is a set of catalytic processes that can be used to produce fuels and chemicals from synthesis gas (mixture of CO and H2, which can be derived from natural gas, coal, or biomass. Biomass to Liquid via Fischer–Tropsch (BTL-FT synthesis is gaining increasing interests from academia and industry because of its ability to produce carbon neutral and environmentally friendly clean fuels; such kinds of fuels can help to meet the globally increasing energy demand and to meet the stricter environmental regulations in the future. In the BTL-FT process, biomass, such as woodchips and straw stalk, is firstly converted into biomass-derived syngas (bio-syngas by gasification. Then, a cleaning process is applied to remove impurities from the bio-syngas to produce clean bio-syngas which meets the Fischer–Tropsch synthesis requirements. Cleaned bio-syngas is then conducted into a Fischer–Tropsch catalytic reactor to produce green gasoline, diesel and other clean biofuels. This review will analyze the three main steps of BTL-FT process, and discuss the issues related to biomass gasification, bio-syngas cleaning methods and conversion of bio-syngas into liquid hydrocarbons via Fischer–Tropsch synthesis. Some features in regard to increasing carbon utilization, enhancing catalyst activity, maximizing selectivity and avoiding catalyst deactivation in bio-syngas conversion process are also discussed.

Bioremediation in soil contaminated with hydrocarbons in Colombia.

OpenAIRE

María Alejandra Trujillo Toro; Juan Fernando Ramírez Quirama

2012-01-01

This study analyzes bioremediation processes of hydrocarbon contaminated soils in Colombia as a sustainable alternative to the deterioration of environmental quality by hydrocarbon spillage. According to national and international environmental law, all waste contaminated with hydrocarbons is considered dangerous waste, and therefore it cannot be released in the ground, water or be incinerated. Such legislation has motivated companies around the world to implement treatment processes for cont...

Hydrocarbon productivities in different Botryococcus strains: comparative methods in product quantification.

Science.gov (United States)

Eroglu, Ela; Okada, Shigeru; Melis, Anastasios

2011-08-01

Six different strains of the green microalgae Botryococcus belonging to the A-race or B-race, accumulating alkadiene or botryococcene hydrocarbons, respectively, were compared for biomass and hydrocarbon productivities. Biomass productivity was assessed gravimetrically upon strain growth in the laboratory under defined conditions. Hydrocarbon productivities were measured by three different and independent experimental approaches, including density equilibrium of the intact cells and micro-colonies, spectrophotometric analysis of hydrocarbon extracts, and gravimetric quantitation of eluted hydrocarbons. All three hydrocarbon-quantitation methods yielded similar results for each of the strains examined. The B-race microalgae Botryococcus braunii var. Showa and Kawaguchi-1 constitutively accumulated botryococcene hydrocarbons equivalent to 30% and 20%, respectively, of their overall biomass. The A-race microalgae Botryococcus braunii, varieties Yamanaka, UTEX 2441 and UTEX LB572 constitutively accumulated alkadiene hydrocarbons ranging from 14% to 13% and 10% of their overall biomass, respectively. Botryococcus sudeticus (UTEX 2629), a morphologically different green microalga, had the lowest hydrocarbon accumulation, equal to about 3% of its overall biomass. Results validate the density equilibrium and spectrophotometric analysis methods in the quantitation of botryococcene-type hydrocarbons. These analytical advances will serve in the screening and selection of B. braunii and of other microalgae in efforts to identify those having a high hydrocarbon content for use in commercial applications.

Radiation synthesis of the nano-scale materials

Energy Technology Data Exchange (ETDEWEB)

Yonghong, Ni; Zhicheng, Zhang; Xuewu, Ge; Xiangling, Xu [Department of Applied Chemistry, Univ. of Science and Technology of China, Hefei (China)

2000-03-01

Some recent research jobs on fabricating the nano-scale materials via {gamma}-irradiation in our laboratory are simply summarized in this paper. The main contents contain four aspects: (1) the preparation of metal alloy - powders; (2) the fabrication of polymer -metal nano-composites in aqueous solution, micro-emulsion and emulsion systems; (3) the synthesis of metal sulfide nano-particles and (4) the preparation of the ordered nano-structure materials. The corresponding preparation processes are also simply described. (author)

Radiation synthesis of the nano-scale materials

International Nuclear Information System (INIS)

Ni Yonghong; Zhang Zhicheng; Ge Xuewu; Xu Xiangling

2000-01-01

Some recent research jobs on fabricating the nano-scale materials via γ-irradiation in our laboratory are simply summarized in this paper. The main contents contain four aspects: (1) the preparation of metal alloy - powders; (2) the fabrication of polymer -metal nano-composites in aqueous solution, micro-emulsion and emulsion systems; (3) the synthesis of metal sulfide nano-particles and (4) the preparation of the ordered nano-structure materials. The corresponding preparation processes are also simply described. (author)

Qualitative TLC determination of some polycyclic aromatic hydrocarbons in sugar-beet

Directory of Open Access Journals (Sweden)

BILJANA D. SKRBIC

2005-10-01

Full Text Available The presence of polycyclic or polynuclear aromatic hydrocarbons (PAHs were investigated in sugar-beet from a local sugar factory in the district of Vojvodina. The sugar-beet was cultivated on areas near roads with intensive traffic. The procedure for the preparation and determination of these compounds included saponification of the sample, several liquid–liquid extraction systems and a silica gel column clean-up. The purified sample solution was analysed by thin layer chromatography (TLC on silica gel with cyclohexane as the developing solvent. Benzo(bfluoranthene and benzo(aanthracene and/or benzo(apyrene were detected at concentrations greater than the allowed limits in food.

Intramolecular Nicholas reactions in the synthesis of dibenzocycloheptanes. Synthesis of allocolchicine NSC 51046 and analogues and the formal synthesis of (-)-allocolchicine.

Science.gov (United States)

Djurdjevic, Sinisa; Yang, Fei; Green, James R

2010-12-03

The preparation of dibenzocycloheptyne-Co(2)(CO)(6) complexes by intramolecular Nicholas reactions of biaryl-2-propargyl alcohol-Co(2)(CO)(6) derivatives is described. Reductive decomplexation of the dibenzocycloheptyne-Co(2)(CO)(6) complexes affords the corresponding dibenzocycloheptenes, individual members of which have been employed in a formal total synthesis of (-)-allocolchicine, the preparation of 6,7-dihydro-3,4,9,10,11-pentamethoxy-5H-dibenzo[a,c]cyclohepten-5-one, and the enantioselective total syntheses of NSC 51046 and its 3,8,9,10-tetramethoxy regioisomer.