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Sample records for activated carbon prepared

  1. Activated Carbon Preparation and Modification for Adsorption

    Science.gov (United States)

    Cao, Yuhe

    . The adsorption capacities of these active carbon samples were almost three times that of zeolite. However, the un-modified active carbon had the highest adsorption capacity for butanol vapor (259.6 mg g-1), compared to 222.4 mg g-1 after 10% H2O2 hydrothermal treatment. Both modified and un-modified active carbon can be easily regenerated for repeatable adsorption by heating to 150 °C. Therefore, surface oxygen groups significantly reduced the adsorption capacity of active carbons for butanol vapor. In addition, original active carbon and AC samples modified by nitric acid hydrothermal modification were assessed for their ability to adsorb butanol vapor. The specific surface area and oxygen-containing functional groups of AC were tested before and after modification. The adsorption capacity of unmodified AC samples were the highest. Hydrothermal oxidation of AC with HNO3 increased the surface oxygen content, Brunauer-Emmett-Teller (BET) surface area, micropore, mesopore and total pore volume of AC. Although the pore structure and specific surface area were greatly improved after hydrothermal oxidization with 4 M HNO3, the increased oxygen on the surface of AC decreased the dynamic adsorption capacity. In order to get high adsorption capacity adsorbents, we used corn stalk as precursor to fabricate porous carbon. ACs were prepared through chemical activation of biochar from whole corn stalk (WCS) and corn stalk pith (CSP) at varying temperatures using potassium hydroxide as the activating agent. ACs were characterized via pore structural analysis and scanning electron microscopy (SEM). These adsorbents were then assessed for their adsorption capacity for butanol vapor. It was found that WCS activated at 900 °C for 1 h (WCS-900) had optimal butanol adsorption characteristics. The BET surface area and total pore volume of the WCS-900 were 2330 m2 g-1 and 1.29 cm3 g-1, respectively. The dynamic adsorption capacity of butanol vapor was 410.0 mg g-1, a 185.1 % increase

  2. Preparation of a MFI zeolite coating on activated carbon

    NARCIS (Netherlands)

    van der Vaart, R; van der Vaart, R.; Bosch, H.; Keizer, Klaas; Reith, T.

    1997-01-01

    A new and simple method for the preparation of MFI zeolite coated activated carbon is presented. Suitable nucleation sites for the growth of zeolites were introduced to the carbon by adding hydrophilic montmorillonite clay to the carbon substrate. A gas tight MFI zeolite coating was obtained on this

  3. Preparation of a MFI zeolite coating on activated carbon

    OpenAIRE

    van der Vaart, R.; Bosch, H.; Keizer, Klaas; Reith, T.

    1997-01-01

    A new and simple method for the preparation of MFI zeolite coated activated carbon is presented. Suitable nucleation sites for the growth of zeolites were introduced to the carbon by adding hydrophilic montmorillonite clay to the carbon substrate. A gas tight MFI zeolite coating was obtained on this modified substrate by hydrothermal growth.

  4. Preparation and Characterization of Activated Carbon from Household Waste Foods

    Directory of Open Access Journals (Sweden)

    Iman Hussein Zainulabdeen

    2018-01-01

    Full Text Available Waste food residues are considered as suitable raw materials for the production of low cost adsorbents. In this work, activated carbons was perpetrating from household waste food (orange peels, banana peels, walnut shells, olive stones and their mixture.  Chemical carbonization at 500?C for 1.5hr was used to prepare carbons and their activation by KOH and CaCl2 solutions for 24h. Then added 0.1g of activated carbons to the solution of blue dyeprepared laboratory to demonstrate the activation of the types of activated carbons prepared toremove the blue dye. The results indicated that characteristics (yield, burn off, density, moisturecontent, ash content, pore volume, porosity percent, Iodine number, methyl blue number andremoval percent of methyl blue for all activated carbons were compared with commercialactivated carbon. It has been found that activated carbon from orange peels and mixturesactivated with CaCl2 had the best adsorption properties reach to the (80, 77.5% removal bluedye respectively and iodine numbers (741, 735mg/g . This low coast activated carbons can beused for wastewater treatment.

  5. Preparation and characterization of activated carbons from albizia ...

    African Journals Online (AJOL)

    Activated carbon was prepared from the pods of Albizia saman for the purpose of converting the waste to wealth. The pods were thoroughly washed with water to remove any dirt, air- dried and cut into sizes of 2-4 cm. The prepared pods were then carbonised in a muffle furnace at temperatures of 4000C, 5000C, 6000C ...

  6. Preparation of activated carbon from a renewable agricultural ...

    African Journals Online (AJOL)

    In this study, element composition of pruning mulberry shoot was evaluated by element analysis. On the basis of this, pruning mulberry shoot–based activated carbon was prepared from by chemical activation with phosphoric acid (H3PO4), which particles were displayed by the scanning electron microscope (SEM) ...

  7. Properties of Activated Carbon Prepared from Coconut Shells in ...

    African Journals Online (AJOL)

    Materials commonly used for preparation of activated carbons include coal and coconut shells. Ghana generates over 30,000 tonnes of coconut shells annually from coconut oil processing activities but apart from a small percentage of the shells, which is burned as fuel, the remaining is usually dumped as waste.

  8. Highly porous activated carbons prepared from carbon rich Mongolian anthracite by direct NaOH activation

    Energy Technology Data Exchange (ETDEWEB)

    Byamba-Ochir, Narandalai [School of Chemical Engineering, Chonnam National University, 77 Yongbong-Ro, Gwangju 61186 (Korea, Republic of); Shim, Wang Geun [Department of Polymer Science and Engineering, Sunchon National University, 255 Jungang-Ro, Suncheon, Jeollanam-Do 57922 (Korea, Republic of); Balathanigaimani, M.S., E-mail: msbala@rgipt.ac.in [Department of Chemical Engineering, Rajiv Gandhi Institute of Petroleum Technology, Ratapur Chowk, Rae Bareli, 229316 Uttar Pradesh (India); Moon, Hee, E-mail: hmoon@jnu.ac.kr [School of Chemical Engineering, Chonnam National University, 77 Yongbong-Ro, Gwangju 61186 (Korea, Republic of)

    2016-08-30

    Highlights: • Highly porous carbon materials from Mongolian anthracite by chemical activation. • Cheaper and eco-friendly activation process has been employed. • Activated carbons with graphitic structure and energetically heterogeneous surface. • Surface hydrophobicity and porosity of the activated carbons can be controlled. - Abstract: Highly porous activated carbons (ACs) were prepared from Mongolian raw anthracite (MRA) using sodium hydroxide as an activation agent by varying the mass ratio (powdered MRA/NaOH) as well as the mixing method of chemical agent and powdered MRA. The specific BET surface area and total pore volume of the prepared MRA-based activated carbons (MACs) are in the range of 816–2063 m{sup 2}/g and of 0.55–1.61 cm{sup 3}/g, respectively. The pore size distribution of MACs show that most of the pores are in the range from large micropores to small mesopores and their distribution can be controlled by the mass ratio and mixing method of the activating agent. As expected from the intrinsic property of the MRA, the highly graphitic surface morphology of prepared carbons was confirmed from Raman spectra and transmission electron microscopy (TEM) studies. Furthermore the FTIR and XPS results reveal that the preparation of MACs with hydrophobic in nature is highly possible by controlling the mixing conditions of activating agent and powdered MRA. Based on all the results, it is suggested that the prepared MACs could be used for many specific applications, requiring high surface area, optimal pore size distribution, proper surface hydrophobicity as well as strong physical strength.

  9. Evaluation of the activated carbon prepared from the algae ...

    African Journals Online (AJOL)

    The batch removal of copper (II) ions from aqueous solution and wastewater using the activated carbon prepared from Gracilaria by acid decomposition was investigated. The effect of pH, biosorption time, adsorbent dose, and metal ions concentration, were considered. The most effective pH was found to be 4.0.

  10. Lead removal in aqueous solution by activated carbons prepared ...

    African Journals Online (AJOL)

    Three activated carbons prepared from vegetable matters of Gabonese biomass are being investigated as adsorbents for the removal of Pb (II) ions from aqueous solutions by means of batch technique. The equilibrium adsorption level was determined to be a function of pH, contact time, temperature and adsorbent dosage.

  11. Activated Carbon Prepared in a Novel Gas Fired Static Bed ...

    African Journals Online (AJOL)

    Activated Carbon Prepared in a Novel Gas Fired Static Bed Pyrolysis-Gasification Reactor for Gold Di-Cyanide Adsorption. ... The PDF file you selected should load here if your Web browser has a PDF reader plug-in installed (for example, a recent version of Adobe Acrobat Reader). If you would like more information about ...

  12. Urea adsorption by activated carbon prepared from palm kernel shell

    Science.gov (United States)

    Ooi, Chee-Heong; Sim, Yoke-Leng; Yeoh, Fei-Yee

    2017-07-01

    Dialysis treatment is crucial for patients suffer from renal failure. The dialysis system removes the uremic toxin to a safe level in a patient's body. One of the major limitations of the current hemodialysis system is the capability to efficiently remove uremic toxins from patient's body. Nanoporous materials can be applied to improve the treatment. Palm kernel shell (PKS) biomass generated from palm oil mills can be utilized to prepare high quality nanoporous activated carbon (AC) and applied for urea adsorption in the dialysis system. In this study, AC was prepared from PKS via different carbonization temperatures and followed by carbon dioxide gas activation processes. The physical and chemical properties of the samples were studied. The results show that the porous AC with BET surface areas ranging from 541 to 622 m2g-1 and with total pore volumes varying from 0.254 to 0.297 cm3g-1, are formed with different carbonization temperatures. The equilibrium constant for urea adsorption by AC samples carbonized at 400, 500 and 600 °C are 0.091, 0.287 and 0.334, respectively. The increase of carbonization temperatures from 400 to 600 °C resulted in the increase in urea adsorption by AC predominantly due to increase in surface area. The present study reveals the feasibility of preparing AC with good porosity from PKS and potentially applied in urea adsorption application.

  13. Highly porous activated carbons prepared from carbon rich Mongolian anthracite by direct NaOH activation

    Science.gov (United States)

    Byamba-Ochir, Narandalai; Shim, Wang Geun; Balathanigaimani, M. S.; Moon, Hee

    2016-08-01

    Highly porous activated carbons (ACs) were prepared from Mongolian raw anthracite (MRA) using sodium hydroxide as an activation agent by varying the mass ratio (powdered MRA/NaOH) as well as the mixing method of chemical agent and powdered MRA. The specific BET surface area and total pore volume of the prepared MRA-based activated carbons (MACs) are in the range of 816-2063 m2/g and of 0.55-1.61 cm3/g, respectively. The pore size distribution of MACs show that most of the pores are in the range from large micropores to small mesopores and their distribution can be controlled by the mass ratio and mixing method of the activating agent. As expected from the intrinsic property of the MRA, the highly graphitic surface morphology of prepared carbons was confirmed from Raman spectra and transmission electron microscopy (TEM) studies. Furthermore the FTIR and XPS results reveal that the preparation of MACs with hydrophobic in nature is highly possible by controlling the mixing conditions of activating agent and powdered MRA. Based on all the results, it is suggested that the prepared MACs could be used for many specific applications, requiring high surface area, optimal pore size distribution, proper surface hydrophobicity as well as strong physical strength.

  14. Preparation of activated carbon fabrics from cotton fabric precursor

    Science.gov (United States)

    Salehi, R.; Dadashian, F.; Abedi, M.

    2017-10-01

    The preparation of activated carbon fabrics (ACFs) from cotton fabric was performed by chemical activation with phosphoric acid (H3PO4). The operation conditions for obtaining the ACFs with the highest the adsorption capacity and process yield, proposed. Optimized conditions were: impregnation ratio of 2, the rate of temperature rising of 7.5 °C min‑1, the activation temperature of 500 °C and the activation time of 30 min. The ACFs produced under optimized conditions was characterized by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The surface area and pore volume of carbon nanostructures was characterized by BET nitrogen adsorption isotherm at 77 °K. The pore size distribution calculated from the desorption branch according to BJH method. The iodine number of the prepared ACFs was determined by titration at 30 °C based on the ASTM D4607-94. The results showed the improvement of porous structure, fabric shape, surface area (690 m2/g), total pore volume (0.3216 cm3/g), and well-preserved fibers integrity.

  15. Preparation of Active Carbon by Additional Activation with Potassium Hydroxide and Characterization of Their Properties

    Directory of Open Access Journals (Sweden)

    Bronislaw Buczek

    2016-01-01

    Full Text Available A commercially available activated carbon was used to prepare active carbon via reactivation with KOH at 750°C. Active carbon was obtained with 60.5% yield. The resulting active carbon showed a well-developed porous structure with specific surface area 2939 m2/g, total pore volume 1.488 cm3/g, and micropore volume 1.001 cm3/g. Process reactivation of carbon changes its particle size as well as density properties and increases by nearly twice the amounts of methane and carbon dioxide adsorbed under high pressure conditions. Such active carbon may be used to enrich methane or carbon dioxide by pressure swing adsorption technique. Other possible applications of reactivated carbon are storage of hydrogen and methane and sequestration of carbon dioxide.

  16. Preparation and Characterization of Activated Carbons from Parthenium biomass by Physical and Chemical Activation Techniques

    Directory of Open Access Journals (Sweden)

    Rajeshwari Sivaraj

    2010-01-01

    Full Text Available Parthenium hysterphorous (Linn, a perennial weed of no known beneficial use was introduced as a containment of food grains imported from US with P1480 scheme. The colonization efficiency of the weed was much higher than other indigenous weeds resulting in the reduction of cultivable areas of agricultural lands. Therefore, attention was focused to find out the potential use of its biomass. In the present study the preparation and characterization of activated carbons by physical and chemical activation methods are reported and aims to prepare relatively well developed porous activated carbons as well as study various conditions and parameters that were involved during the process. Among the carbons prepared Zncl2 impregnated carbon at the ratio of 1 was found to possess the characteristic features of an efficient adsorbent. Experimental results showed that pyrolytic and activation conditions leading to various final average temperatures had significant effect on the properties of activated carbons prepared.

  17. Preparation And Characterization Of Cr/Activated Carbon Catalyst From Palm Empty Fruit Bunch

    OpenAIRE

    Zainal Fanani; Dedi Rohendi; Tri Kurnia Dewi; Muhammad Dzulfikar A

    2016-01-01

    Preparation and characterization of Cr/activated carbon catalyst from palm empty fruit bunch had been done. The research were to determine the effect of carbonization temperature towards adsorption of ammonia, iodine number, metilen blue number, and porosity of activated carbon and Cr/activated carbon catalyst. The determination of porosity include surface area, micropore volume and total pore volume. The results showed the best carbonization temperature activated carbon and Cr/activated carb...

  18. Preparation and characterization of activated carbon produced from pomegranate seeds by ZnCl 2 activation

    Science.gov (United States)

    Uçar, Suat; Erdem, Murat; Tay, Turgay; Karagöz, Selhan

    2009-08-01

    In this study, pomegranate seeds, a by-product of fruit juice industry, were used as precursor for the preparation of activated carbon by chemical activation with ZnCl 2. The influence of process variables such as the carbonization temperature and the impregnation ratio on textural and chemical-surface properties of the activated carbons was studied. When using the 2.0 impregnation ratio at the carbonization temperature of 600 °C, the specific surface area of the resultant carbon is as high as 978.8 m 2 g -1. The results showed that the surface area and total pore volume of the activated carbons at the lowest impregnation ratio and the carbonization temperature were achieved as high as 709.4 m 2 g -1 and 0.329 cm 3 g -1. The surface area was strongly influenced by the impregnation ratio of activation reagent and the subsequent carbonization temperature.

  19. Preparation and characterization of active carbon using palm kernel ...

    African Journals Online (AJOL)

    Chemical activation was done by heating a mixture of carbonized material and the activating agents at a temperature of 700C to form a paste, followed by subsequent cooling and using the active carbon to purify effluents from a Bottling Company. NaCl, KOH, H2SO4 and H3PO4 were used as the activating agents at 1M ...

  20. Activated Carbon Prepared in a Novel Gas Fired Static Bed ...

    African Journals Online (AJOL)

    Michael O. Mensah

    2015-12-02

    Dec 2, 2015 ... The problem of gold recovery from their ores by adsorption onto activated carbon is complex and a number of adsorption mechanisms of gold adsorption from potassium or sodium aurocyanide solutions and gold chloride solutions onto activated carbons have been proposed over the years in the literature ...

  1. Lead removal in aqueous solution by activated carbons prepared ...

    African Journals Online (AJOL)

    AJL

    and battery manufacturing, paint, paper and pulp industries. ... metals aqueous solutions is realizable using many methods such as: ion exchange, .... Table 1. Characteristics of the activated carbon. Activated carbons. Ash (%). Acidity neutralizations (meq/L). Surface area (m2/g). NaOH. NaHCO3. Na2CO3. CAo. 1.3. 0.8.

  2. Preparation, characterization and phenol adsorption capacity of activated carbons from African beech wood sawdust

    OpenAIRE

    N.T. Abdel-Ghani; G.A. El-Chaghaby; F. Helal

    2016-01-01

    In the present study, different activated carbons were prepared from carbonized African beech wood sawdust by potassium hydroxide activation. The activated carbons were characterized by brunauer–emmett–teller, scanning electron microscope, fourier transform infrared spectroscopy, and thermogravimetric analyzer. The phenol adsorption capacity of the prepared carbons was evaluated. The different factors affecting phenol’s removal were studied including: contact time, solution pH and initial phe...

  3. Preparation And Characterization Of Cr/Activated Carbon Catalyst From Palm Empty Fruit Bunch

    Directory of Open Access Journals (Sweden)

    Zainal Fanani

    2016-02-01

    Full Text Available Preparation and characterization of Cr/activated carbon catalyst from palm empty fruit bunch had been done. The research were to determine the effect of carbonization temperature towards adsorption of ammonia, iodine number, metilen blue number, and porosity of activated carbon and Cr/activated carbon catalyst. The determination of porosity include surface area, micropore volume and total pore volume. The results showed the best carbonization temperature activated carbon and Cr/activated carbon catalyst at 700°C. The adsorption ammonia of activated carbon and Cr/activated carbon catalyst as 6.379 mmol/g and 8.1624 mmol/g. The iodine number of activated carbon and Cr/activated carbon catalyst as 1520.16 mg/g and 1535.67 mg/g. The metilen blue number of activated carbon and Cr/activated carbon catalyst as 281.71 mg/g and 319.18 mg/g. The surface area of activated carbon and Cr/activated carbon catalyst as 1527.80 m2/g and 1652.58 m2/g. The micropore volume of activated carbon and Cr/activated carbon catalyst as 0.7460 cm3/g and 0.8670 cm3/g. The total pore volume of activated carbon and Cr/activated carbon catalyst as 0.8243 cm3/g and 0.8970 cm3/g.

  4. Binding of nickel and zinc ions with activated carbon prepared from ...

    African Journals Online (AJOL)

    Activated carbon was prepared from sugar cane fibre by carbonizing at 500 oC for 30 minutes. This was followed by activation with ammonium chloride. The activated carbon was characterised in terms of pH, bulk density, ash content, surface area and surface charge. Equilibrium sorption of nickel and zinc ions by the ...

  5. Preparation and characterization of activated carbon from water ...

    African Journals Online (AJOL)

    Water hyacinth and water spinach were used as novel precursor materials for the production of powdered activated carbons. They were activated chemically with H3PO4, KOH, H2O2 pyrolyzed at 4500C and characterized in terms of pH, density, surface area, iodine number, porosity, ash content and moisture content.

  6. Preparation of activated carbon from a renewable agricultural ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-05-10

    May 10, 2010 ... India, Korea, Japan and Thailand where the leaves are used as food for silkworms (Wang ... mulberry shoot is a normal work in mulberry field industry annually; C: Parasitic insect and ..... Figure 7. Scanning electronic micrograph for the pruning mulberry shoot-based activated carbon (A: magnification: 100× ...

  7. Preparation of activated carbons from walnut wood: a study of microporosity and fractal dimension

    Science.gov (United States)

    Gómez-Serrano, Vicente; Cuerda-Correa, Eduardo M.; Fernández-González, M. Carmen; Alexandre-Franco, María F.; Macías-García, Antonio

    2005-04-01

    Agricultural and forest residues constitute an extraordinarily important source of precursors for the manufacture of activated carbons. Activated carbons are well known as porous solids with a highly developed apparent surface area. In the present work, activated carbon has been prepared from forest residues of walnut tree wood (a raw material not studied until now) by physical activation. Raw material has been carbonized between 573 and 1073 K and afterwards activated in air at temperatures between 623 and 823 K. The apparent surface area, micropore volume, mesopore volume and fractal dimension of the samples prepared have been calculated.

  8. Preparation of creating active carbon from cigarette filter waste using microwave-induced KOH activation

    Science.gov (United States)

    Hamzah, Yanuar; Umar, Lazuardi

    2017-05-01

    For the first time, cigarette filter waste, which is an environmental hazardous material, is used as basic material prepared for creating activated carbon (AC) via KOH chemical activation using a microwave input power of 630 W and irradiation time of 20 minutes. Active carbon was characterized by TGA, x-ray diffraction, scanning electron microscopy, energy dispersive x-ray, nitrogen adsorption-desorption, and absorption of methylene blue (MB). The results of x-ray diffraction showed that active carbon has a semi-crystalline structure with peaks of 2θ of 22.87° and 43.70°. Active carbon microstructure analysis showed that the layer height (Lc ) is inversely proportional to the width of the layer (La ), and the distance between the two layers is d002 and d100 , which depends significantly on the ratio of AC: KOH. It was found that the optimum BET surface area and adsorption capacity for MB were 328.13 m2 / g and 88.76 m2 / g, respectively. The results revealed the potential to prepare activated carbon from cigarette filter waste using microwave irradiation.

  9. Experimental design to optimize preparation of activated carbons for use in water treatment.

    Science.gov (United States)

    Baçaoui, Abdelaziz; Dahbi, Abderrahman; Yaacoubi, Abdelrani; Bennouna, Chakib; Maldonado-Hódar, Francisco J; Rivera-Utrilla, José; Carrasco-Marín, Francisco; Moreno-Castilla, Carlos

    2002-09-01

    A series of seven activated carbons was obtained for use in drinking water treatments by steam-activation of olive-waste cakes. This raw material is an abundant and cheap waste byproduct of oil production, making these activated carbons economically feasible. The activated carbons, prepared by the one step method, were characterized, and the evolution of their characteristics (yield, adsorption capacities, and porosity) was analyzed as a function of the experimental parameters (activation temperature and activation time), using the Doehlert matrix. The Doehlert matrix allows the response surface to be studied with a good quality parameter estimation of the quadratic model. Each response has been described by a second order model that was adequate to predict responses in all experimental regions. The coefficients of the postulated model were calculated from the experimental responses by means of least squares regression, using the NEMROD software. We determined the region in which the optimum values of both activation temperature and activation time were achieved for the preparation of activated carbons suitable for use in water treatments. The "optimal activated carbon" was experimentally obtained, and its characteristic parameters showed a good agreement with those calculated from the model. The results obtained for activated carbons prepared by the one-step method were compared with those for activated carbons prepared by the two-step method. The characteristics of activated carbons obtained by the one-step and two-step methods showed that "one-step" activated carbons have a highly developed porous texture formed mainly of large macropores and micropores, whereas "two-step" activated carbons have a predominance of mesopores and narrow micropores. These activated carbons from olive-waste cakes showed a high capacity to adsorb herbicides (2,4-dichlorophenoxyacetic acid, 2,4-D; and 2-methyl, 4-chlorophenoxyacetic acid, MCPA) from water, with adsorption capacity

  10. Microwave-Assisted Preparation of Activated Carbon from Eupatorium Adenophorum: Effects of Preparation Parameters

    Science.gov (United States)

    Cheng, Song; Zhang, Shengzhou; Zhang, Libo; Xia, Hongying; Peng, Jinhui; Wang, Shixing

    2017-09-01

    Eupatorium adenophorum, global exotic weeds, was utilized as feedstock for preparation of activated carbon (AC) via microwave-induced KOH activation. Influences of the three vital process parameters - microwave power, activation time and impregnation ratio (IR) - have been assessed on the adsorption capacity and yield of AC. The process parameters were optimized utilizing the Design Expert software and were identified to be a microwave power of 700 W, an activation time of 15 min and an IR of 4, with the resultant iodine adsorption number and yield being 2,621 mg/g and 28.25 %, respectively. The key parameters that characterize the AC such as the brunauer emmett teller (BET) surface area, total pore volume and average pore diameter were estimated to be 3,918 m2/g, 2,383 ml/g and 2.43 nm, respectively, under the optimized process conditions. The surface characteristics of AC were characterized by Fourier transform infrared spectroscopy, scanning electron microscope and Transmission electron microscope.

  11. High hydrogen storage capacity of porous carbons prepared by using activated carbon.

    Science.gov (United States)

    Wang, Huanlei; Gao, Qiuming; Hu, Juan

    2009-05-27

    A kind of activated carbon with further carbon dioxide and potassium hydroxide activations for hydrogen storage was investigated. The carbon dioxide and potassium hydroxide activations have apparently different effects on the pore structures and textures of the activated carbon which closely associated with the hydrogen storage properties. The potassium hydroxide activation can remarkably donate microporosity to the frameworks of the activated carbon. One of the resultant porous carbons exhibited a high surface area of up to 3190 m(2) g(-1) and large gravimetric hydrogen uptake capacity of 7.08 wt % at 77 K and 20 bar, which is one of the largest data reported for the porous carbon materials. This result suggests that the porous carbon with large amounts of active sites, high surface area, and high micropore volume related to optimum pore size could achieve high gravimetric hydrogen storage.

  12. Preparation of activated carbon from walnut shell and its application in industrial wastewater

    Science.gov (United States)

    Jiang, Yilin

    2017-05-01

    With the development of China's industry, the content of heavy metal ions in wastewater is increasing. In this paper, analyzed the performance of activated carbon prepared from walnut shell by chemical activation method, and conduct the experimental research on the factors influencing the performance of activated carbon by using the control variable method. The best method for preparing activated carbon from walnut shell was put forward. In the industrial wastewater treatment technology to lay the foundation for the application. Lay the foundation for the promotion of industrial wastewater treatment technology.

  13. Preparation of sodium dodecyl sulphate-functionalized activated carbon from Gnetum gnemon shell for dye adsorption

    Science.gov (United States)

    Fatimah, Is; Yahya, Amri; Sasti, Rilis Akista Tria

    2017-03-01

    Preparation of functionalized activated carbon from Gnetum gnemon shell was investigated. This work aimed to prepare highly active adsorbent for dye adsorption process by carbonization of Gnetum gnemon shell followed by functionalization using sodium dodecyl sulphate (SDS) to form SDS-modified activated carbon (SDS-AC). The study of physicochemical character change was performed by SEM and FTIR analysis while the adsorptivity of the materials was tested in methylene blue adsorption. According to the results, it is found that SDS-AC exhibits the greater adsorptivity compared to AC.

  14. Preparation of steam activated carbon from rubberwood sawdust (Hevea brasiliensis) and its adsorption kinetics.

    Science.gov (United States)

    Prakash Kumar, B G; Shivakamy, K; Miranda, Lima Rose; Velan, M

    2006-08-25

    Activated carbon was produced from a biowaste product, rubberwood sawdust (RWSD) using steam in a high temperature fluidized bed reactor. Experiments were carried out to investigate the influence of various process parameters such as activation time, activation temperature, particle size and fluidising velocity on the quality of the activated carbon. The activated carbon was characterized based on its iodine number, methylene blue number, Brauner Emmet Teller (BET) surface area and surface area obtained using the ethylene glycol mono ethyl ether (EGME) retention method. The best quality activated carbon was obtained at an activation time and temperature of 1h and 750 degrees C for an average particle size of 0.46 mm. The adsorption kinetics shows that pseudo-second-order rate fitted the adsorption kinetics better than pseudo-first-order rate equation. The adsorption capacity of carbon produced from RWSD was found to be 1250 mg g(-1) for the Bismark Brown dye. The rate constant and diffusion coefficient for intraparticle transport were determined for steam activated carbon. The characteristic of the prepared activated carbon was found comparable to the commercial activated carbon.

  15. Preparation of steam activated carbon from rubberwood sawdust (Hevea brasiliensis) and its adsorption kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Prakash Kumar, B.G. [Department of Chemical Engineering, Alagappa College of Technology, Anna University, Chennai 600 025 (India); Shivakamy, K. [Centralised Waste Management Facility, Bhabha Atomic Research Centre, Kalpakkam 603 102 (India); Miranda, Lima Rose [Department of Chemical Engineering, Alagappa College of Technology, Anna University, Chennai 600 025 (India); Velan, M. [Department of Chemical Engineering, Alagappa College of Technology, Anna University, Chennai 600 025 (India)]. E-mail: velan@annauniv.edu

    2006-08-25

    Activated carbon was produced from a biowaste product, rubberwood sawdust (RWSD) using steam in a high temperature fluidized bed reactor. Experiments were carried out to investigate the influence of various process parameters such as activation time, activation temperature, particle size and fluidising velocity on the quality of the activated carbon. The activated carbon was characterized based on its iodine number, methylene blue number, Brauner Emmet Teller (BET) surface area and surface area obtained using the ethylene glycol mono ethyl ether (EGME) retention method. The best quality activated carbon was obtained at an activation time and temperature of 1 h and 750 deg. C for an average particle size of 0.46 mm. The adsorption kinetics shows that pseudo-second-order rate fitted the adsorption kinetics better than pseudo-first-order rate equation. The adsorption capacity of carbon produced from RWSD was found to be 1250 mg g{sup -1} for the Bismark Brown dye. The rate constant and diffusion coefficient for intraparticle transport were determined for steam activated carbon. The characteristic of the prepared activated carbon was found comparable to the commercial activated carbon.

  16. Amoxicillin removal from aqueous solution using activated carbon prepared by chemical activation of olive stone.

    Science.gov (United States)

    Limousy, Lionel; Ghouma, Imen; Ouederni, Abdelmottaleb; Jeguirim, Mejdi

    2017-04-01

    A chemical-activated carbon (CAC) was prepared by phosphoric acid activation of olive stone. The CAC was characterized using various analytical techniques and evaluated for the removal of amoxicillin from aqueous solutions under different operating conditions (initial concentration, 12.5-100 mg L -1 , temperature, 20-25 °C, contact time, 0-7000 min). The CAC characterization indicates that it is a microporous carbon with a specific surface area of 1174 m 2 /g and a pore volume of 0.46 cm 3 /g and contains essentially acidic functional groups. The adsorption tests indicated that 93 % of amoxicillin was removed at 20 °C for 25 mg L -1 initial concentration. Moreover, it was found that adsorption capacity increased with contact time and temperature. Kinetic study shows that the highest correlation was obtained for the pseudo-second-order kinetic model, which confirms that the process of adsorption of amoxicillin is mainly chemisorption. Using the intraparticle diffusion model, the mechanism of the adsorption process was determined. The equilibrium data analysis showed that the Sips and Langmuir models fitted well the experimental data with maximal adsorption capacities of 67.7 and 57 mg/g, respectively, at 25 °C. The chemical-activated carbon of olive stones could be considered as an efficient adsorbent for amoxicillin removal from aqueous solutions.

  17. Activated Carbon Prepared in a Novel Gas Fired Static Bed ...

    African Journals Online (AJOL)

    A novel gas fired static-bed pyrolysis-gasification/activation reactor has been designed. A special feature of the reactor is its rectangular cross-section, having a square groove positioned symmetrically at the bottom part of the reactor, which allows efficient heat transfer into the bed of material being pyrolysed. The reactor is ...

  18. Adsorption studies of methylene blue and phenol onto vetiver roots activated carbon prepared by chemical activation.

    Science.gov (United States)

    Altenor, Sandro; Carene, Betty; Emmanuel, Evens; Lambert, Jacques; Ehrhardt, Jean-Jacques; Gaspard, Sarra

    2009-06-15

    Vetiver roots have been utilized for the preparation of activated carbon (AC) by chemical activation with different impregnation ratios of phosphoric acid, X(P) (gH(3)PO(4)/g precursor): 0.5:1; 1:1 and 1.5:1. Textural characterization, determined by nitrogen adsorption at 77K shows that mixed microporous and mesoporous structures activated carbons (ACs) with high surface area (>1000 m(2)/g) and high pore volume (up to 1.19 cm(3)/g) can be obtained. The surface chemical properties of these ACs were investigated by X-ray photoelectron spectroscopy (XPS) and Boehm titration. Their textural and chemical characteristics were compared to those of an AC sample obtained by steam activation of vetiver roots. Classical molecules used for characterizing liquid phase adsorption, phenol and methylene blue (MB), were used. Adsorption kinetics of MB and phenol have been studied using commonly used kinetic models, i.e., the pseudo-first-order model, the pseudo-second-order model, the intraparticle diffusion model and as well the fractal, BWS (Brouers, Weron and Sotolongo) kinetic equation. The correlation coefficients (R(2)) and the normalized standard deviation Deltaq (%) were determined showing globally, that the recently derived fractal kinetic equation could best describe the adsorption kinetics for the adsorbates tested here, indicating a complex adsorption mechanism. The experimental adsorption isotherms of these molecules on the activated carbon were as well analysed using four isotherms: the classical Freundlich, Langmuir, Redlich-Peterson equations, but as well the newly published deformed Weibull Brouers-Sotolongo isotherm. The results obtained from the application of the equations show that the best fits were achieved with the Brouers-Sotolongo equation and with the Redlich-Peterson equation. Influence of surface functional groups towards MB adsorption is as well studied using various ACs prepared from vetiver roots and sugar cane bagasse. Opposite effects governing MB

  19. Preparation of activated carbon from waste plastics polyethylene terephthalate as adsorbent in natural gas storage

    Science.gov (United States)

    Yuliusman; Nasruddin; Sanal, A.; Bernama, A.; Haris, F.; Ramadhan, I. T.

    2017-02-01

    The main problem is the process of natural gas storage and distribution, because in normal conditions of natural gas in the gas phase causes the storage capacity be small and efficient to use. The technology is commonly used Compressed Natural Gas (CNG) and Liquefied Natural Gas (LNG). The weakness of this technology safety level is low because the requirement for high-pressure CNG (250 bar) and LNG requires a low temperature (-161°C). It takes innovation in the storage of natural gas using the technology ANG (Adsorbed Natural Gas) with activated carbon as an adsorbent, causing natural gas can be stored in a low pressure of about 34.5. In this research, preparation of activated carbon using waste plastic polyethylene terephthalate (PET). PET plastic waste is a good raw material for making activated carbon because of its availability and the price is a lot cheaper. Besides plastic PET has the appropriate characteristics as activated carbon raw material required for the storage of natural gas because the material is hard and has a high carbon content of about 62.5% wt. The process of making activated carbon done is carbonized at a temperature of 400 ° C and physical activation using CO2 gas at a temperature of 975 ° C. The parameters varied in the activation process is the flow rate of carbon dioxide and activation time. The results obtained in the carbonization process yield of 21.47%, while the yield on the activation process by 62%. At the optimum process conditions, the CO2 flow rate of 200 ml/min and the activation time of 240 minutes, the value % burn off amounted to 86.69% and a surface area of 1591.72 m2/g.

  20. Preparation of porous bio-char and activated carbon from rice husk by leaching ash and chemical activation.

    Science.gov (United States)

    Ahiduzzaman, Md; Sadrul Islam, A K M

    2016-01-01

    Preparation porous bio-char and activated carbon from rice husk char study has been conducted in this study. Rice husk char contains high amount silica that retards the porousness of bio-char. Porousness of rice husk char could be enhanced by removing the silica from char and applying heat at high temperature. Furthermore, the char is activated by using chemical activation under high temperature. In this study no inert media is used. The study is conducted at low oxygen environment by applying biomass for consuming oxygen inside reactor and double crucible method (one crucible inside another) is applied to prevent intrusion of oxygen into the char. The study results shows that porous carbon is prepared successfully without using any inert media. The adsorption capacity of material increased due to removal of silica and due to the activation with zinc chloride compared to using raw rice husk char. The surface area of porous carbon and activated carbon are found to be 28, 331 and 645 m(2) g(-1) for raw rice husk char, silica removed rice husk char and zinc chloride activated rice husk char, respectively. It is concluded from this study that porous bio-char and activated carbon could be prepared in normal environmental conditions instead of inert media. This study shows a method and possibility of activated carbon from agro-waste, and it could be scaled up for commercial production.

  1. Microporous activated carbons prepared from palm shell by thermal activation and their application to sulfur dioxide adsorption.

    Science.gov (United States)

    Guo, Jia; Lua, Aik Chong

    2002-07-15

    Textural characterization of activated carbons prepared from palm shell by thermal activation with carbon dioxide (CO(2)) gas is reported in this paper. Palm shell (endocarp) is an abundant agricultural solid waste from palm-oil processing mills in many tropical countries such as Malaysia, Indonesia, and Thailand. The effects of activation temperature on the textural properties of the palm-shell activated carbons, namely specific surface area (BET method), porosity, and microporosity, were investigated. The activated carbons prepared from palm shell possessed well-developed porosity, predominantly microporosity, leading to potential applications in gas-phase adsorption for air pollution control. Static and dynamic adsorption tests for sulfur dioxide (SO(2)), a common gaseous pollutant, were carried out in a thermogravimetric analyzer and a packed column configuration respectively. The effects of adsorption temperature, adsorbate inlet concentration, and adsorbate superficial velocity on the adsorptive performance of the prepared activated carbons were studied. The palm-shell activated carbon was found to have substantial capability for the adsorption of SO(2), comparable to those of some commercial products and an adsorbent derived from another biomass.

  2. Preparation, characterization and phenol adsorption capacity of activated carbons from African beech wood sawdust

    Directory of Open Access Journals (Sweden)

    N.T. Abdel-Ghani

    2016-05-01

    Full Text Available In the present study, different activated carbons were prepared from carbonized African beech wood sawdust by potassium hydroxide activation. The activated carbons were characterized by brunauer–emmett–teller, scanning electron microscope, fourier transform infrared spectroscopy, and thermogravimetric analyzer. The phenol adsorption capacity of the prepared carbons was evaluated. The different factors affecting phenol’s removal were studied including: contact time, solution pH and initial phenol concentration. The optimum phenol removal was obtained after a contact time of 300 min. and at an initial phenol solution pH 7. The maximum removal percentages were determined at 5mg/l initial phenol concentration as 79, 93, 94 and 98% for AC0, AC1, AC2 and AC3; respectively. The adsorption of phenol on African beech sawdust activated carbons was found to follow the Lagergren first order kinetics and the intraparticle diffusion mechanism gave a good fit to the experimental data. The isothermal models applied fitted the experimental data in the order: Langmuir> Dubinin–Radushkevich> Freundlich and Temkin.

  3. Microstructure of polyacrylonitrile-based activated carbon fibers prepared from solvent-free coagulation process

    Directory of Open Access Journals (Sweden)

    Norhaniza Yusof

    2016-02-01

    Full Text Available Polyacrylonitrile precursor fibers prepared using a solvent-free coagulation process were stabilized, carbonized, and physically activated by carbon dioxide into activated carbon fibers (ACFs. The activation temperature varied from 600 to 900 °C while the activation time was 1 h. Atomic force microscopy was used to observe the surface morphology, as well as the surface roughness of the ACFs. Higher pyrolysis temperature formed rougher surfaces, and increased the pore sizes. Meanwhile, Fourier transform infrared spectroscopy revealed more conversion of oxygen containing functional groups to carbonaceous materials as the activation temperature increased. Moreover, the microstructure properties were thoroughly characterized by the X-ray photoelectron spectroscopy (XPS and X-ray diffraction (XRD studies. XRD analysis showed that the activation of the ACFs shrank the ordered structure, reducing the D-spacing from 0.358 to 0.347 nm for the fibers prepared at activation temperatures of 600 to 900 °C. Meanwhile, XPS analysis concluded that that the oxygen containing functional groups were still retained even at high activation temperatures while the nitrogen containing functional groups were reduced during the high temperature activation in the CO2 atmosphere.

  4. Elimination of textile dyes using activated carbons prepared from vegetable residues and their characterization.

    Science.gov (United States)

    Peláez-Cid, Alejandra-Alicia; Herrera-González, Ana-María; Salazar-Villanueva, Martín; Bautista-Hernández, Alejandro

    2016-10-01

    In this study, three mesoporous activated carbons prepared from vegetable residues were used to remove acid, basic, and direct dyes from aqueous solutions, and reactive and vat dyes from textile wastewater. Granular carbons obtained by chemical activation at 673 K with phosphoric acid from prickly pear peels (CarTunaQ), broccoli stems (CarBrocQ), and white sapote seeds (CarZapQ) were highly efficient for the removal of dyes. Adsorption equilibrium studies were carried out in batch systems and treated with Langmuir and Freundlich isotherms. The maximum adsorption capacities calculated from the Langmuir isotherms ranged between 131.6 and 312.5 mg/g for acid dyes, and between 277.8 and 500.0 mg/g for basic dyes at 303 K. Our objective in this paper was to show that vegetable wastes can serve as precursors for activated carbons that can be used for the adsorption of dyes. Specifically CarBrocQ was the best carbon produced for the removal of textile dyes. The color removal of dyes present in textile wastewaters was compared with that of a commercial powdered carbon, and it was found that the carbons produced using waste material reached similar efficiency levels. Carbon samples were characterized by bulk density, point of zero charge, thermogravimetric analysis, elemental analysis, Fourier transform infrared spectroscopy, scanning electron microscopy, methylene blue adsorption isotherms at 303 K, and nitrogen adsorption isotherms at 77 K (SBET). The results show that the activated carbons possess a large specific surface area (1025-1177 m(2)/g) and high total pore volume (1.06-2.16 cm(3)/g) with average pore size diameters between 4.1 and 8.4 nm. Desorption and regeneration tests were made to test the viability of reusing the activated carbons. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Preparation of the sludge activated carbon with domestic sludge mixed agricultural straw

    Science.gov (United States)

    Wang, Laifu; Wang, Yan; Lian, Jingyan

    2017-01-01

    Urban sewage sludge with complicated composition produce largely each year, pollution problem and resource utilization has increasingly become the focus of attention. Sewage sludge is utilized to prepare adsorbent that is a new type method. Agricultural stalks was added to material (urban sewage sludge) and activator (ZnCl2), calcined under the condition of no inert gas, and obtained domestic sludge activated carbon. The properties were measured by iodine adsorption value and BET, discussed influence factors of sludge activated carbon preparation, including activator concentration, solid-liquid ratio, calcific temperature and calcific time. The best process condition of orthogonal experiment had explored that activated time is 10 minutes, calcific temperature is 350°C, the activator concentration ZnCl2 is 3 mol/L and the mixing ratio of raw materials and activator is approximately 1:5. The iodine adsorption value and the optimal BET of as-obtained domestic sludge activated carbon is 445.06 mg/g, 525.31m2/g, respectively.

  6. Preparation and Properties of Paraffin/TiO2/Active-carbon Composite Phase Change Materials

    Directory of Open Access Journals (Sweden)

    HAO Yong-gan

    2016-11-01

    Full Text Available A novel composite phase change materials (PCMs of paraffin/TiO2/active-carbon was prepared by a microemulsion method, where paraffin acted as a PCM and titanium dioxide (TiO2 as matrix material, and a small amount of active carbon was added to improve the thermal conductivity. The compositions, morphology and thermal properties of the paraffin/TiO2/active-carbon composite PCMs were characterized by XRD, SEM, TGA and DSC respectively. The shape stability during phase change process of this composite was also tested. The results show that paraffin is well encapsulated by TiO2 matrix, and thus exhibiting excellent shape-stabilized phase change feature. Besides, this composite PCM also presents superhydrophobic property. Therefore, these multifunctional features will endow PCMs with important application potential in energy efficient buildings.

  7. Study on the preparation of straw activated carbon and its phenol adsorption properties

    Science.gov (United States)

    Chen, Liping

    2017-01-01

    Using sunflower straw as raw materials to manufacture straw activated carbon-modified by phosphoric acidand adsorption isotherm of phenol on straw activated carbon was studied in a batch reactor. The physical properties of the prepared straw activated carbons were characterized by scanning electron microscopy. The effect of various parameters, adsorbent dose, pH and temperature, were studied on optimum conditions. The results have shown that the absorbent was efficient, the removal ratio of phenol up to 99.36% with an adsorbent dosage of 16 g·L-1, a pH of 6.0-8.0, at 25 °C. The experimental adsorption data fitted reasonably well to the Langmuir isotherm, the maximum adsorption capacity was 109.89 mg/g. The process of adsorption is a exothermic process.

  8. Optimization of activation temperature on the preparation of sliced porous activated carbon from date fronds by physical activation

    Directory of Open Access Journals (Sweden)

    Shoaib Muhammad

    2016-01-01

    Full Text Available Saudi Arabia is the major date producer in the world. In order to get the maximum production from date tree there is a need to prune the trees on annual basis and is considered as a serious environmental threat. The single step procedure for the synthesis of porous activated carbon (AC from Saudi date tree fronds using mixture of gases (N2 and CO2 was carried out at different carbonization/activation temperatures staring from 700°C to 1000°C at a ramp rate of 10 degree per minute. Alloy 330 horizontal reactor was used in tube furnace. Flow rate of N2 and CO2 gases were kept at 150 and 50ml/min respectively. Results reveal that at 850oC larger surface area was achieved and can offer higher potential to produce activated carbon of greater adsorption capacity from date fronds waste. The BET surface areas of the activated carbons prepared at 850°C after 30 minutes activation time are 1094 m2/g.

  9. A method for preparing ferric activated carbon composites adsorbents to remove arsenic from drinking water.

    Science.gov (United States)

    Zhang, Qiao Li; Lin, Y C; Chen, X; Gao, Nai Yun

    2007-09-30

    Iron oxide/activated carbon (FeO/AC) composite adsorbent material, which was used to modify the coal-based activated carbon (AC) 12 x 40, was prepared by the special ferric oxide microcrystal in this study. This composite can be used as the adsorbent to remove arsenic from drinking water, and Langmuir isotherm adsorption equation well describes the experimental adsorption isotherms. Then, the arsenic desorption can subsequently be separated from the medium by using a 1% aqueous NaOH solution. The apparent characters and physical chemistry performances of FeO/AC composite were investigated by X-ray diffraction (XRD), nitrogen adsorption, scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Batch and column adsorption experiments were carried out to investigate and compare the arsenic removal capability of the prepared FeO/AC composite material and virgin activated carbon. It can be concluded that: (1) the main phase present in this composite are magnetite (Fe(3)O(4)), maghemite (gamma-Fe(2)O(3)), hematite (alpha-Fe(2)O(3)) and goethite (alpha-FeO(OH)); (2) the presence of iron oxides did not significantly affect the surface area or the pore structure of the activated carbon; (3) the comparisons between the adsorption isotherms of arsenic from aqueous solution onto the composite and virgin activated carbon showed that the FeO/AC composite behave an excellent capacity of adsorption arsenic than the virgin activated carbon; (4) column adsorption experiments with FeO/AC composite adsorbent showed that the arsenic could be removed to below 0.01 mg/L within 1250 mL empty bed volume when influent concentration was 0.5mg/L.

  10. Preparation and characterization of activated carbon fiber (ACF) from cotton woven waste

    Science.gov (United States)

    Zheng, Jieying; Zhao, Quanlin; Ye, Zhengfang

    2014-04-01

    In this study, the activated carbon fibers (ACFs) were prepared using cotton woven waste as precursor. The cotton woven waste was first partly dissolved by 80% phosphoric acid and then was pre-soaked in 7.5% diammonium hydrogen phosphate solution. Finally, carbonization and activation were proceeded to get ACF. The optimum preparation conditions, including carbonization temperature, carbonization time, activation temperature and activation time, were chosen by orthogonal design. Nitrogen adsorption/desorption test was conducted to characterize the prepared ACF's pore structure. Fourier transform infrared spectroscopy (FTIR) analysis, X-ray photoelectron spectroscopy (XPS) and environmental scanning electron microscope (ESEM) were employed to characterize its chemical properties and morphology. Adsorption of oilfield wastewater was used to evaluate its adsorption properties. The results show that the prepared ACF is in the form of fiber, with the sectional diameters of 11.7 × 2.6 μm and the surface area of 789 m2/g. XPS results show that carbon concentration of the prepared ACF is higher than that of the commercial ACF. When the prepared ACF dosage is 6 g/L, over 80% of COD and over 70% of chrominance can be removed after 24 h of adsorption at 18 °C. We demonstrated the catalytic growth of m-axial InxGa1-xN (0.10 ≤ x ≤ 0.17) nanocolumn arrays with high crystallinity on silicon substrates using metal-organic chemical vapor deposition with trimethylindium (TMIn), triethylgallium (TEGa), and ammonia as precursors. The high quality of InGaN nanocolumns (NCs) were believed to be due to the utilization of TEGa that achieved less carbon impurities and offered more comparable vapor pressure with that of TMIn at low temperature. In addition, these NCs were grown in non-polar m-axis, which the internal electric field of the InGaN that often deteriorates the device performances might be able to be eliminated. Furthermore, the bandgap of this InGaN can be modulated from

  11. Factors Affecting the Adsorption of Trivalent Chromium Ions by Activated Carbon Prepared from Waste Rubber Tyres

    Directory of Open Access Journals (Sweden)

    Sylvia E. Benjamin

    2017-08-01

    Full Text Available Economic gains are generally the outcome of industrialization and consequently urbanization. However, positive fiscal index generates a negative impact on natural environment sources heaving pollutant burden on soil, air and water. Industries throw tones of contaminated water into soil and water bodies without proper treatment and create a potential threat for both living and non-living species. Chromium in trivalent state (Cr3+ is added in water bodies and soil through waste water from tanneries, cooling water systems, chemical and pulp and paper industries. The present research work aims at the preparation of an inexpensive activated carbon prepared from non- degradable waste scrap rubber tyres. The carbon produced from scrap rubber tyres was activated by 5% solution of BaCl2 and 0.4 N solution of HCl and verified by ethylene blue solution. The adsorption capacity of the Tyre activated carbon (TAC was investigated for different parameters i.e., initial chromium (III ion concentration, activated carbon dosage, contact/ stirring time and pH. The adsorption capacity of TAC depends on the initial metal ion concentration and the TAC dose. pH of the chromium solution effects the adsorption capacity of TAC due to the formation of tetra hydroxochromate(III complexes,. The results show that TAC offers a cost effective reclamation process for the removal of Cr3+ from effluent waters.

  12. Physical and chemical properties and adsorption type of activated carbon prepared from plum kernels by NaOH activation.

    Science.gov (United States)

    Tseng, Ru-Ling

    2007-08-25

    Activated carbon was prepared from plum kernels by NaOH activation at six different NaOH/char ratios. The physical properties including the BET surface area, the total pore volume, the micropore ratio, the pore diameter, the burn-off, and the scanning electron microscope (SEM) observation as well as the chemical properties, namely elemental analysis and temperature programmed desorption (TPD), were measured. The results revealed a two-stage activation process: stage 1 activated carbons were obtained at NaOH/char ratios of 0-1, surface pyrolysis being the main reaction; stage 2 activated carbons were obtained at NaOH/char ratios of 2-4, etching and swelling being the main reactions. The physical properties of stage 2 activated carbons were similar, and specific area was from 1478 to 1887m(2)g(-1). The results of reaction mechanism of NaOH activation revealed that it was apparently because of the loss ratio of elements C, H, and O in the activated carbon, and the variations in the surface functional groups and the physical properties. The adsorption of the above activated carbons on phenol and three kinds of dyes (MB, BB1, and AB74) were used for an isotherm equilibrium adsorption study. The data fitted the Langmuir isotherm equation. Various kinds of adsorbents showed different adsorption types; separation factor (R(L)) was used to determine the level of favorability of the adsorption type. In this work, activated carbons prepared by NaOH activation were evaluated in terms of their physical properties, chemical properties, and adsorption type; and activated carbon PKN2 was found to have most application potential.

  13. Effect of KOH activation in the desulfurization process of activated carbon prepared by sewage sludge & corn straw.

    Science.gov (United States)

    Zeng, Fan; Liao, Xiaofeng; Hu, Hui; Liao, Li

    2017-12-07

    Series sludge-straw based activated carbons were prepared by sewage sludge and corn straw with potassium hydroxide activation, and the desulfurization performance of activated carbons were studied. To obtain the best desulfurization performance, the optimum ratio between the raw materials and the activator was investigated. The results showed that as the mass ratio of sewage sludge, corn straw and potassium hydroxide was 3:7:2, the activated carbon obtained the best breakthrough and saturation sulfur sorption capacity, which were 12.38 and 5.74 times of sample prepared by the non-activated raw materials, respectively. The appropriate KOH could improve the microporosity and alkaline groups, meanwhile reduce the lactone groups, which were all beneficial to their desulfurization performance. The chemical adsorption process of desulfurization can be simplified to four main steps, and the main desulfurization products are elemental sulfur and sulfate. Implication Sewage sludge (SS) and corn straw (CS) both were great production, wide distribution, readily available in China. Much attention has been paid on how to deal with them effectively. Based on the environment protection idea of waste treatment with waste and resource recycling, low-cost adsorbents were prepared by them. The proposed method can be expanded to the municipal solid waste recycling programs and renewable energy plan. Thus, proceed with the study of prepared AC by SS and straw as a carbon-based dry desulfurization agent could obtain huge social, economical and environmental benefits.

  14. Preparation of activated carbons from macadamia nut shell and coconut shell by air activation

    Energy Technology Data Exchange (ETDEWEB)

    Tam, M.S.; Antal, M.J. Jr.

    1999-11-01

    A novel, three-step process for the production of high-quality activated carbons from macadamia nut shell and coconut shell charcoals is described. In this process the charcoal is (1) heated to a high temperature (carbonized), (2) oxidized in air following a stepwise heating program from low (ca. 450 K) to high (ca. 660 K) temperatures (oxygenated), and (3) heated again in an inert environment to a high temperature (activated). By use of this procedure, activated carbons with surface areas greater than 1,000 m{sub 2}/g are manufactured with an overall yield of 15% (based on the dry shell feed). Removal of carbon mass by the development of mesopores and macropores is largely responsible for increases in the surface area of the carbons above 600 m{sub 2}/g. Thus, the surface area per gram of activated carbon can be represented by an inverse function of the yield for burnoffs between 15 and 60%. These findings are supported by mass-transfer calculations and pore-size distribution measurements. A kinetic model for gasification of carbon by oxygen, which provides for an Eley-Rideal type reaction of a surface oxide with oxygen in air, fits the measured gasification rates reasonably well over the temperature range of 550--660 K.

  15. Optimization of Activated Carbons Prepared by H3PO4 and Steam Activation of Oil Palm Shells

    Directory of Open Access Journals (Sweden)

    Daouda Kouotou

    2013-01-01

    Full Text Available In this study, activated carbons were prepared from oil palm shells by physicochemical activation. The methodology of experimental design was used to optimize the preparation conditions. The influences of the impregnation ratio (0.6–3.4 and the activation temperature between 601°C and 799°C on the following three responses: activated carbon yield (R/AC-H3PO4, the iodine adsorption (I2/AC-H3PO4, and the methylene blue adsorption (MB/AC-H3PO4 results were investigated using analysis of variance (ANOVA to identify the significant parameters. Under the experimental conditions investigated, the activation temperature of 770°C and impregnation ratio of 2/1 leading to the R/AC-H3PO4 of 52.10%, the I2/AC-H3PO4 of 697.86 mg/g, and the MB/AC-H3PO4 of 346.25 mg/g were found to be optimum conditions for producing activated carbon with well compromise of desirability. The two factors had both synergetic and antagonistic effects on the three responses studied. The micrographs of activated carbons examined with scanning electron microscopy revealed that the activated carbons were found to be mainly microporous and mesoporous.

  16. Characterization, preparation, and reaction mechanism of hemp stem based activated carbon

    Science.gov (United States)

    Zhang, Ji; Gao, Jianmin; Chen, Yao; Hao, Xinmin; Jin, Xiaojuan

    In this study, hemp stem was used to prepare high surface area activated carbon (AC) by KOH activation. The structure, characterization, thermal and structure analysis on reaction mechanisms of AC were investigated via N2 adsorption-desorption isotherm, Fourier transform infrared (FTIR) spectroscopy and thermogravimetric-mass (TG-MS) spectrometry. Results show that when the impregnation ratio is 4.5:1 (KOH/char), the activation temperature is 800 °C, and the activation time is 1.5 h, AC has the highest specific surface area of 2388 m2·g-1 and exhibits narrow pore size distributions with maxima in the micropore areas. The reaction mechanism of AC from hemp stems by KOH activation is as follows: In the first carbonization stage, it is primarily because of the substitution, scission, and oxidization reactions of methylene. Then in the second activation stage, it is mainly related to polycyclic reactions, reactions between carbon and KOH, and reactions between intermediate potassium oxide species and carbon.

  17. Preparation of manganese dioxide loaded activated carbon adsorbents and their desulfurization performance

    Science.gov (United States)

    Zhang, Jiaojing; Wang, Guojian; Wang, Wenyi; Song, Hua; Wang, Lu

    2016-12-01

    Manganese dioxide loaded activated carbon adsorbents (MnO2/AC) were prepared and characterized by N2 adsorption-desorption, BET method, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectrometry (FT-IR) and scanning electron microscopy (SEM). Effects of preparation conditions and adsorption conditions on desulfurization performance of the adsorbents were studied in a fixed-bed adsorption apparatus. Experimental results show that the surface area and pore volume of MnO2/AC decreased compared with the unmodified activated carbon, but the adsorption capacity to H2S was improved greatly. A suitable H2S removal activity was obtained with manganese dioxide to activated carbon ratio of 1.1: 1 and the calcination temperature of 250°C. At the adsorption temperature of 40°C and gas flow rate of 20 mL/min, the H2S saturation capacity and H2S removal rate reached up to 713.25 mg/g and 89.9%, respectively.

  18. Optimization of microwave-assisted rubberwood sawdust based activated carbon preparation conditions for methylene blue removal

    Science.gov (United States)

    Khasri, Azduwin; Ahmad, Mohd Azmier

    2017-10-01

    Optimum preparation conditions of rubberwood sawdust based activated carbon (RSAC) for methylene blue (MB) dye removal was studied. RSAC was produced by applying physiochemical activation method by using potassium hydroxide as a chemical agent which accompanied by carbon dioxide gasification under microwave heating. The effects of microwave power, irradiation time and impregnation ratio on two types of responses namely MB removal and RSAC yield using the center composite design (CCD) were also included in this study. The preparation variables correlation for responses was developed by two quadratic models. Optimum preparation conditions of RSAC were obtained at microwave power, irradiation time and IR of 354 W, 4.5 minutes and 0.98, respectively, which resulted MB removal and yield of 83.79% and 28%, respectively. The average pore diameter, surface area and total pore volume of optimized RSAC were 4.12 nm, 796.33 m2/g and 0.4219 cm3/g, respectively. This sample was found to has well-developed pores on its surface and can be a promising adsorbent for MB removal from aqueous solution.

  19. Preparation and characterization of activated carbon from sunflower seed oil residue via microwave assisted K2CO3 activation.

    Science.gov (United States)

    Foo, K Y; Hameed, B H

    2011-10-01

    Sunflower seed oil residue, a by-product of sunflower seed oil refining, was utilized as a feedstock for preparation of activated carbon (SSHAC) via microwave induced K(2)CO(3) chemical activation. SSHAC was characterized by Fourier transform infrared spectroscopy, nitrogen adsorption-desorption and elemental analysis. Surface acidity/basicity was examined with acid-base titration, while the adsorptive properties of SSHAC were quantified using methylene blue (MB) and acid blue 15 (AB). The monolayer adsorption capacities of MB and AB were 473.44 and 430.37 mg/g, while the Brunauer-Emmett-Teller surface area, Langmuir surface area and total pore volume were 1411.55 m(2)/g, 2137.72 m(2)/g and 0.836 cm(3)/g, respectively. The findings revealed the potential to prepare high surface area activated carbon from sunflower seed oil residue by microwave irradiation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Optimization of Preparation Program for Biomass Based Porous Active Carbon by Response Surface Methodology Based on Adsorptive Property

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    ZHANG Hao

    2017-06-01

    Full Text Available With waste walnut shell as raw material, biomass based porous active carbon was made by microwave oven method. The effects of microwave power, activation time and mass fraction of phosphoric acid on adsorptive property of biomass based porous active carbon in the process of physical activation of active carbon precursor were studied by response surface method and numerical simulation method, the preparation plan of biomass based porous active carbon was optimized, and the optimal biomass based porous active carbon property was characterized. The results show that three factors affect the adsorptive property of biomass based porous active carbon, but the effect of microwave power is obviously more significant than that of mass fraction of phosphoric acid, and the effect of mass fraction of phosphoric acid is more significant than that of activation time. The optimized preparation conditions are:microwave power is 746W, activation time is 11.2min and mass fraction of phosphoric acid is 85.9% in the process of physical activation of activated carbon precursor by microwave heating method. For the optimal biomass based porous active carbon, the adsorption value of iodine is 1074.57mg/g, adsorption value of methylene blue is 294.4mL/g and gain rate is 52.1%.

  1. Effect of Activation Temperature and Heating Duration on Physical Characteristics of Activated Carbon Prepared from Agriculture Waste

    Directory of Open Access Journals (Sweden)

    Tham Yee Jun

    2010-01-01

    Full Text Available This study was conducted to determine the physical characteristics of activated carbon prepared from durian shell in varied heating durations from 10 min to 30 min and activation temperatures of 400C and 500C. Durian shells have been characterized in term of ultimate and proximate analysis, chemical composition and thermal behaviour with a view to be used as activated carbon precursor. Durian shell activated carbon was prepared by impregnating 10g of sample in 10% (v/v concentration of phosphoric acid for 24 h, followed by carbonization at 400C and 500C with different heating durations under nitrogen atmosphere. The results showed that various treatment conditions affect the percentage of yield, BET surface area, micropore volume, and average pore diameter. The highest surface area (SBET 1024 m2/g was obtained at 500C and 20 min of heating duration with 63% of yield and 0.21 cm3/g micropore volume.

  2. TEXTURAL AND CHEMICAL CHARACTERISATION OF ACTIVATED CARBONS PREPARED FROM RICE HUSK (ORYZA SATIVA USING A TWO- STAGE ACTIVATION PROCESS

    Directory of Open Access Journals (Sweden)

    JOSEPH G. COLLIN

    2008-12-01

    Full Text Available Activated carbons from agro-industrial wastes; rice husk; were prepared by physical and chemical activation using phosphoric acid as the dehydrating agent. A two-stage activation process method was used; with semi-carbonisation stage at 200oC for 15 minutes as the first stage followed by an activation stage at 500oC for 45 minutes as the second stage. The precursor material with the impregnation agent was exposed straightaway to semi-carbonization and activation temperature unlike the specific temperature progression as reported in the literature. All experiments were conducted in a laboratory scale muffle furnace under static conditions in a self generated atmosphere covering process parameters such as impregnation ratios. We found that by using this method, the AC5 had the highest iodine number and methylene blue adsorption capacity which was 506.6 mg/g and 319.0 mg/g respectively.

  3. Preparation of carbon-supported Bi/Ti composites and its catalytic activity under solar irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Peng; Wu, Yanlin; Shi, Jin; Liu, Dan; Dong, Wenbo, E-mail: wbdong@fudan.edu.cn

    2014-02-15

    Carbon-supported photocatalysts of Bi/Ti oxides (Bi/Ti-C) were synthesized by a facile sol–gel process. Carbon was mounted as support substrate by controlling calcination temperature. The as-prepared materials were characterized through X-ray diffraction, and the N{sub 2} adsorption–desorption isotherm and surface texture of Bi/Ti-C at 673 K were observed by scanning electron microscopy and transmission electron microscopy. Characterization results revealed that BiOCl was the major phase of the catalytic composites, and that Bi/Ti-673 K was endowed with the porous structure of the coated C. The photocatalytic degradation activity of these samples to Rhodamine B was determined through ultraviolet-visible spectrophotometry. The composite prepared at 673 K demonstrated the highest photocatalytic efficiency. The addition of C avoided the need to modify the surface area of the crystals. In addition, the photocatalytic activities of the Bi/Ti composites were significantly improved by the compounded microstructure.

  4. Preparation of mesoporous carbon from fructose using zinc-based activators

    OpenAIRE

    Tutik Setianingsih; Indriana Kartini; Yateman Arryanto

    2015-01-01

    Mesoporous carbons were synthesized from fructose using activators of zinc silicate (ZS), zinc borate (ZB), and zinc borosilicate (ZBS). The synthesis involves 3 steps, including caramelization of sugar, carbonization of caramel, and washing of carbon to separate the activator from the carbon. The solid products were characterized by N2 gas adsorption-desorption, X-ray diffraction, FTIR spectrophotometry, and Transmission Electron Microscopy. The pore characterizations of the carbons in...

  5. Preparation of sulfurized powdered activated carbon from waste tires using an innovative compositive impregnation process.

    Science.gov (United States)

    Yuan, Chung-Shin; Lin, Hsun-Yu; Wu, Chun-Hsin; Liu, Ming-Han; Hung, Chung-Hsuang

    2004-07-01

    The objective of this study is to develop an innovative compositive impregnation process for preparing sulfurized powdered activated carbon (PAC) from waste tires. An experimental apparatus, including a pyrolysis and activation system and a sulfur (S) impregnation system, was designed and applied to produce sulfurized PAC with a high specific surface area. Experimental tests involved the pyrolysis, activation, and sulfurization of waste tires. Waste-tire-derived PAC (WPAC) was initially produced in the pyrolysis and activation system. Experimental results indicated that the Brunauer-Emmett-Teller (BET) surface area of WPAC increased, and the average pore radius of WPAC decreased, as water feed rate and activation time increased. In this study, a conventional direct impregnation process was used to prepare the sulfurized PAC by impregnating WPAC with sodium sulfide (Na2S) solution. Furthermore, an innovative compositive impregnation process was developed and then compared with the conventional direct impregnation process. Experimental results showed that the compositive impregnation process produced the sulfurized WPAC with high BET surface area and a high S content. A maximum BET surface area of 886 m2/g and the S content of 2.61% by mass were obtained at 900 degrees C and at the S feed ratio of 2160 mg Na2S/g C. However, the direct impregnation process led to a BET surface area of sulfurized WPAC that decreased significantly as the S content increased.

  6. Preparation, Surface and Pore Structure of High Surface Area Activated Carbon Fibers from Bamboo by Steam Activation

    Directory of Open Access Journals (Sweden)

    Xiaojun Ma

    2014-06-01

    Full Text Available High surface area activated carbon fibers (ACF have been prepared from bamboo by steam activation after liquefaction and curing. The influences of activation temperature on the microstructure, surface area and porosity were investigated. The results showed that ACF from bamboo at 850 °C have the maximum iodine and methylene blue adsorption values. Aside from the graphitic carbon, phenolic and carbonyl groups were the predominant functions on the surface of activated carbon fiber from bamboo. The prepared ACF from bamboo were found to be mainly type I of isotherm, but the mesoporosity presented an increasing trend after 700 °C. The surface area and micropore volume of samples, which were determined by application of the Brunauer-Emmett-Teller (BET and t-plot methods, were as high as 2024 m2/g and 0.569 cm3/g, respectively. It was also found that the higher activation temperature produced the more ordered microcrystalline structure of ACF from bamboo.

  7. Adsorption of caffeine on mesoporous activated carbon fibers prepared from pineapple plant leaves.

    Science.gov (United States)

    Beltrame, Karla K; Cazetta, André L; de Souza, Patrícia S C; Spessato, Lucas; Silva, Taís L; Almeida, Vitor C

    2018-01-01

    The present work reports the preparation of activated carbon fibers (ACFs) from pineapple plant leaves, and its application on caffeine (CFN) removal from aqueous solution. The preparation procedure was carried out using the H3PO4 as activating agent and slow pyrolysis under N2 atmosphere. The characterization of materials was performed from the N2 adsorption and desorption isotherms, scanning electron microscopy (SEM), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Raman spectroscopy, Boehm titration and pHpzc method. ACFs showed high BET surface area value (SBET = 1031m2 g-1), well-developed mesoporous structure (mesopore volume of 1.27cm³ g-1) and pores with average diameter (DM) of 5.87nm. Additionally, ACFs showed features of fibrous material with predominance of acid groups on its surface. Adsorption studies indicated that the pseudo-second order kinetic and Langmuir isotherm models were that best fitted to the experimental data. The monolayer adsorption capacity was found to be 155.50mgg-1. thermodynamic studies revealed that adsorption process is spontaneous, exothermic and occurs preferably via physisorption. The pineapple leaves are an efficient precursor for preparation of ACFs, which were successful applied as adsorbent material for removal of caffeine from the aqueous solutions. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Preparation of biochar by simultaneous carbonization, magnetization and activation for norfloxacin removal in water.

    Science.gov (United States)

    Wang, Bo; Jiang, Yan-Song; Li, Fa-Yun; Yang, Deng-Yue

    2017-06-01

    Activated magnetic biochar (AMB) was prepared with corn stalks, reed stalks, and willow branches by simultaneous carbonization, magnetization, and activation, and used for norfloxacin removal in water. The exploration results showed that the zeta potential was positively charged at pH 2-10. These prepared activated magnetic biochars have a large specific surface area (>700m(2)·g(-1)) and pore volume (>0.3cm(3)·g(-1)). The quasi-second-order kinetic adsorption equation could better describe the adsorption of NOR on AMB. The Langmuir isotherm showed the better fitting results on AMB. The AMB showed the strong adsorption of NOR, and the saturated adsorption capacity of corn activated magnetic biochar was the highest, 7.6249mg·g(-1). The adsorption of NOR on AMB was a spontaneous endothermic process. The effect of pH on the adsorption behaviors of NOR on AMB was not obvious, and AMB had a good adsorption effect on NOR in a wide pH range. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Activated carbon fibers/poly(lactic-co-glycolic) acid composite scaffolds: Preparation and characterizations

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Yanni [State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, Shanghai 201620 (China); College of Materials Science and Engineering, Donghua University, Shanghai 201620 (China); Han, Hao [College of Materials Science and Engineering, Donghua University, Shanghai 201620 (China); Bayer Material Science China Co., Ltd, Shanghai 200120 (China); Quan, Haiyu; Zang, Yongju; Wang, Ning; Ren, Guizhi [College of Materials Science and Engineering, Donghua University, Shanghai 201620 (China); Xing, Melcolm [Department of Mechanical Engineering, Faculty of Engineering and Department of Biochemistry and Genetics, Faculty of Medicine P.I., Manitoba Institute of Child Health, University of Manitoba, Winnipeg, Manitoba (Canada); Wu, Qilin, E-mail: wql@dhu.edu.cn [State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, Shanghai 201620 (China); College of Materials Science and Engineering, Donghua University, Shanghai 201620 (China)

    2014-10-01

    The present work is a first trial to introduce activated carbon fibers (ACF) with high adsorption capacity into poly(lactic-co-glycolic) acid (PLGA), resulting in a novel kind of scaffolds for tissue engineering applications. ACF, prepared via high-temperature processing of carbon fibers, are considered to possess bioactivity and biocompatibility. The ACF/PLGA composite scaffolds are prepared by solvent casting/particulate leaching method. Increments in both pore quantity and quality over the surface of ACF as well as a robust combination between ACF and PLGA matrix are observed via scanning electron microscopy (SEM). The high adsorption capacity of ACF is confirmed by methylene blue solution absorbency test. The surfaces of ACF are affiliated with many hydrophilic groups and characterized by Fourier transform infrared spectroscopy. Furthermore, the SEM images show that cells possess a favorable spreading morphology on the ACF/PLGA scaffolds. Besides, vivo experiments are also carried out to evaluate the histocompatibility of the composite scaffolds. The results show that ACF have the potential to become one of the most promising materials in biological fields. - Highlights: • ACF with strong adsorption capacity and porous structure for enhanced surface area • The incorporation of ACF promoting the porosity of composite scaffolds • The composite scaffolds having no side effect on cell adhesion and proliferation • The composite scaffolds presenting good biocompatibility in vivo.

  10. Kinetics of adsorption of dyes from aqueous solution using activated carbon prepared from waste apricot

    Energy Technology Data Exchange (ETDEWEB)

    Onal, Yunus [Inonu University, Faculty of Engineering, Department of Chemical Engineering, 44280 Malatya (Turkey)]. E-mail: yonal@inonu.edu.tr

    2006-10-11

    Adsorbent (WA11Zn5) has been prepared from waste apricot by chemical activation with ZnCl{sub 2}. Pore properties of the activated carbon such as BET surface area, pore volume, pore size distribution, and pore diameter were characterized by N{sub 2} adsorption and DFT plus software. Adsorption of three dyes, namely, Methylene Blue (MB), Malachite Green (MG), Crystal Violet (CV), onto activated carbon in aqueous solution was studied in a batch system with respect to contact time, temperature. The kinetics of adsorption of MB, MG and CV have been discussed using six kinetic models, i.e., the pseudo-first-order model, the pseudo-second-order model, the Elovich equation, the intraparticle diffusion model, the Bangham equation, the modified Freundlich equation. Kinetic parameters and correlation coefficients were determined. It was shown that the second-order kinetic equation could describe the adsorption kinetics for three dyes. The dyes uptake process was found to be controlled by external mass transfer at earlier stages (before 5 min) and by intraparticle diffusion at later stages (after 5 min). Thermodynamic parameters, such as {delta}G, {delta}H and {delta}S, have been calculated by using the thermodynamic equilibrium coefficient obtained at different temperatures and concentrations. The thermodynamics of dyes-WA11Zn5 system indicates endothermic process.

  11. Optically active substituted polyacetylene@carbon nanotube hybrids: Preparation, characterization and infrared emissivity property study

    Energy Technology Data Exchange (ETDEWEB)

    Bu, Xiaohai; Zhou, Yuming, E-mail: ymzhou@seu.edu.cn; Zhang, Tao; Wang, Yongjuan; Zhang, Zewu; He, Man

    2014-08-15

    Optically active substituted polyacetylene@multiwalled carbon nanotubes (SPA@MWCNTs) nanohybrids were fabricated by wrapping helical SPA copolymers onto the surface of modified nanotubes through ester bonding linkage. SPA copolymer based on chiral phenylalanine and serine was pre-polymerized by a rhodium zwitterion catalyst in THF, and evidently proved to possess strong optical activity and adopt a predominately one-handed helical conformation. Various characterizations including Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and transmission electron microscopy (TEM) demonstrated that the SPA had been covalently grafted onto the nanotubes without destroying their original graphite structure. The wrapped SPA was found to exhibit an enhancement in thermal stability and still maintained considerable optical activity after grafting. The infrared emissivity property of the nanohybrids at 8–14 μm was investigated in addition. The results indicated that the SPA@MWCNTs hybrid matrix could possess a much lower infrared emissivity value (ε=0.707) than raw MWCNTs, which might be due to synergistic effect of the unique helical conformation of optically active SPA and strengthened interfacial interaction between the organic polymers and inorganic nanoparticles. - Graphical abstract: Optically active SPA@MWCNTs nanohybrids with low infrared emissivity. - Highlights: • Synthesis of optically active SPA copolymer derived from serine and phenylalanine. • Preparation and characterization of optically active SPA@MWCNTs nanohybrids. • Application study of the SPA@MWCNTs nanohybrids (ε=0.707) in lowering the infrared emissivity.

  12. Comparison of sorption capacity and surface area of activated carbon prepared from Jatropha curcas fruit pericarp and seed coat

    Directory of Open Access Journals (Sweden)

    O.M. Ameen

    2012-08-01

    Full Text Available Activated carbons were prepared from fruit pericarp and seed coat of Jatropha curcas using KOH and NaCl as activating agents leading to the production of four samples of activated carbons JPS, JPP, JCS and JCP. The adsorption capacity based on adsorption of methylene blue was determined for each sample. A further study of adsorptive properties of the most efficient activated carbon (JPS was made by contacting it with standard solutions of methylene blue, acetic acid and potassium permanganate. The effects of mass of active carbon used, initial concentration of the solute and the pH of the solution on adsorption performance were investigated. Ash content and percentage fixed carbon were determined for two of the activated carbons (JPS and JCS with the highest adsorptive capacity. Equilibrium study on adsorption was carried out and the adsorption data were analyzed using the Langmuir isotherm. The results obtained indicate that activated carbons from the fruit pericarp and the seed coat of J. curcas can be used as high performance adsorbents with the fruit pericarp activated carbon showing the higher adsorption capacity. The adsorption data fitted well to the Langmuir model and adsorptive area of 824–910 m2/g was obtained for the activated carbon.DOI: http://dx.doi.org/10.4314/bcse.v26i2.2

  13. The potential use of activated carbon prepared from Ziziphus species for removing dyes from waste waters

    Science.gov (United States)

    Regti, Abdelmajid; Laamari, My Rachid; Stiriba, Salah-Eddine; El Haddad, Mohammadine

    2017-11-01

    In this study, the adsorption potential of activated carbon prepared from Ziziphus mauritiana nuts for the removal of methylene blue (MB) from aqueous solution has been investigated using batch mode experiments. The effects of some operating parameters on the removal dye such as, initial pH (2-12), temperature (298-328 K), initial MB concentration (20-100 mg L-1), and contact time (5-70 min) were investigated. Adsorption kinetic showed that the rate adsorption followed the pseudo-second-order kinetic model. Four adsorption isotherms models were applied to experimental equilibrium data (Langmuir, Freundlich, Redlich-Peterson, and Fritz-Schlunder) and the different constants were calculated using non-linear equations models. Fritz-Schlunder model was found the best one to describe the adsorption process which suggests that the adsorption of MB onto activated carbon derived from Ziziphus mauritiana is heterogeneous with a multilayer. Thermodynamic adsorption showed that the process was endothermic and spontaneous in nature.

  14. Preparation and Adsorption Performances of Phragmites australis Activated Carbon with High Acidity

    Directory of Open Access Journals (Sweden)

    FU Cheng-kai

    2017-03-01

    Full Text Available For removal of heavy metals from wastewater and recycling the wetland plants, the present study investigated the viability of using silage of Phragmites australis (PA to prepare activated carbons (ACs with high acidity. BET surface area, porous texture and surface functional characteristics of ACs were analyzed by N2 adsorption/desorption, elemental analysis and Boehm titration method. ACs presented well-developed micro-porosity and favorable surface acidity. The sorption equilibrium data for Ni (Ⅱ and Cd (Ⅱ sorption onto ACs were analyzed by the Langmuir and Freundlich models. The Langmuir model was fitted well to the adsorption behavior. The properties of high surface acidity promoted the adsorption of heavy metals by the silage-treated ACs and the chemical sorption played the key role in the sorption process.

  15. Efficacy evaluation of activated carbon prepared from date stones in cyanide adsorption from synthetic wastewater

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    Bahman Ramavandi

    2013-02-01

    Results: The maximum adsorption capacity of 50.21 mg/g corresponded with Langmuir model. Kinetic evaluation indicated that the adsorption of cyanide ions by the adsorbent clearly followed the pseudo-second order rate reaction. The absorption was pH dependent and the maximum adsorption was done by solutions having pH 9. At an optimum pH 9, over 97% removal of 100 mg/L cyanide was attained for an adsorbent dose of 1.25 g/L during a 40 min contact time. Conclusion: Activated carbon prepared from date stones is an efficient and low-cost adsorbent for removing of different concentrations of cyanide from water and wastewater.

  16. Preparation and Characterisation of Activated Carbon From Pumpkin Seed Shell Using H3PO4

    OpenAIRE

    DEMIRAL, Ilknur; AYDIN ŞAMDAN, Canan

    2016-01-01

    In this study, activated carbons were produced from pumpkin seed shell by chemical activation. In chemical activation, H3PO4 was used as chemical agent. The effects of impregnation ratio (IR) and activation temperature were investigated. Activation temperatures and impregnation ratios were selected in the range of 400–600 °C and 1–3, respectively. The surface area, pore volumes, pore size distribution and average pore diameter of the activated carbons were characterized by N2 adsorption at 77...

  17. The effect of ultrasound on the catalytic activity of alkaline carbons: preparation of N-alkyl imidazoles

    Energy Technology Data Exchange (ETDEWEB)

    Duran-Valle, C.J.; Ferrera-Escudero, S.; Calvino-Casilda, V.; Diaz-Teran, J.; Martin-Aranda, R.M

    2004-11-15

    N-Alkyl imidazoles have been prepared by sonochemical irradiation of imidazole and 1-bromobutane using alkaline promoted carbons. Under the experimental conditions, N-alkyl imidazoles can be prepared with a high activity and selectivity. It is observed that imidazole conversion increases in parallel with increasing basicity of the catalyst. For comparison, the alkylation of imidazole has also been performed in a batch reactor system under thermal activation.

  18. Preparation and Characterization of Activated Carbon Obtained from Plantain (Musa paradisiaca Fruit Stem

    Directory of Open Access Journals (Sweden)

    O. A. Ekpete

    2017-01-01

    Full Text Available Carbonization of carbon obtained from plantain (Musa paradisiaca stem was achieved at a temperature of 400°C for one hour. The carbonized carbon was divided into two parts to be activated separately. The activated carbon CPPAC (carbonized plantain phosphoric acid activated carbon and CPZAC (carbonized plantain zinc chloride activated carbon were produced via the chemical activation process using H3PO4 and ZnCl2. Characterization of pH, bulk density, moisture content, ash content, volatile matter, iodine number, and oxygen functional group was conducted. When comparing the surface properties of both CPPAC and CPZAC with the untreated plantain carbon (UPC, it was observed that there existed significant differences in all properties with the exemption of carboxylic group for CPPAC and phenolic group for both CPPAC and CPZAC, thus signifying that a chemical transformation did occur. When comparing the results obtained from CPPAC to that of CPZAC, CPPAC was more preferable for adsorption due to its low bulk density, low ash content, and high iodine value, signifying thus that the activating agents both reacted differently with the plantain stem.

  19. Preparation And Characterization Of Microporous Activated Carbon From Oil Palm Shell By Physical Activation Using Purified Nitrogen

    Directory of Open Access Journals (Sweden)

    Allwar Allwar

    2012-02-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Oil palm shell, a byproduct of palm oil industry was successfully used as a raw material for the production of highly porous activated carbons. Preparation of activated carbon was carried out by physical activation under nitrogen at various activation temperatures. The nitrogen isotherms show Type I characteristics of microporous activated carbon. The maximum surface areas obtained at 900oC was 936 m2g-1. The morphology structure of the activated carbon indicated the existence of the porosities with different size pores. Keywords: Oil palm shell; Micropores; Physical activation; Nitrogen adsorption-desorption isotherm

  20. Activated carbon prepared from coffee pulp: potential adsorbent of organic contaminants in aqueous solution.

    Science.gov (United States)

    Gonçalves, Maraisa; Guerreiro, Mário César; Ramos, Paulize Honorato; de Oliveira, Luiz Carlos Alves; Sapag, Karim

    2013-01-01

    The processing of coffee beans generates large amounts of solid and liquid residues. The solid residues (pulp, husk and parchment) represent a serious environmental problem and do not have an adequate disposal mechanism. In this work, activated carbons (ACs) for adsorption of organic compounds were prepared from coffee pulp by controlled temperature at different pulp/Na2HPO4 ratios (4:1, 2:1, 5:4 and 1:1). The N2 adsorption/desorption isotherms showed ACs with high quantities of mesopores and micropores and specific surface areas of 140, 150, 450 and 440 m(2)g(-1) for AC 4:1, AC 2:1, AC 5:4 and AC 1:1, respectively. The prepared material AC 5:4 showed a higher removal capacity of the organic contaminants methylene blue (MB), direct red (DR) and phenol than did a Merck AC. The maximum capacities for this AC are approximately 150, 120 and 120 mg g(-1) for MB, DR and phenol, respectively. Thus, a good adsorbent was obtained from coffee pulp, an abundant Brazilian residue.

  1. Removal of phenol by powdered activated carbon prepared from coal gasification tar residue.

    Science.gov (United States)

    Wang, Xiong-Lei; Shen, Jun; Niu, Yan-Xia; Wang, Yu-Gao; Liu, Gang; Sheng, Qing-Tao

    2018-03-01

    Coal gasification tar residue (CGTR) is a kind of environmentally hazardous byproduct generated in fixed-bed coal gasification process. The CGTR extracted by ethyl acetate was used to prepare powdered activated carbon (PAC), which is applied later for adsorption of phenol. The results showed that the PAC prepared under optimum conditions had enormous mesoporous structure, and the iodine number reached 2030.11 mg/g, with a specific surface area of 1981 m 2 /g and a total pore volume of 0.92 ml/g. Especially, without loading other substances, the PAC, having a strong magnetism, can be easily separated after it adsorbs phenol. The adsorption of phenol by PAC was studied as functions of contact time, temperature, PAC dosage, solution concentration and pH. The results showed a fast adsorption speed and a high adsorption capacity of PAC. The adsorption process was exothermic and conformed to the Freundlich models. The adsorption kinetics fitted better to the pseudo-second-order model. These results show that CGTR can be used as a potential adsorbent of phenols in wastewater.

  2. Preparation of Nano-Porous Activated Carbon Aerogel Using a Single-Step Activation Method for Use as High-Power EDLC Electrode in Organic Electrolyte.

    Science.gov (United States)

    Kwon, Soon Hyung; Kim, Bum-Soo; Kim, Sang-Gil; Lee, Byung-Jun; Kim, Myung-Soo; Jung, Ji Chul

    2016-05-01

    Carbon aerogel was chemically activated with KOH using two different activation methods (conventional activation method and single-step activation method) to yield the nano-porous activated carbon aerogel. Both nano-porous activated carbon aerogels exhibited a better capacitive behavior than carbon aerogel in organic electrolyte. However, a drastic decrease in the specific capacitance with increasing current density was observed in the ACA_C (activated carbon aerogel prepared by a conventional activation method), which is a general tendency of carbon electrode for EDLC in organic electrolyte. Interestingly, the specific capacitance of ACA_S electrode (activated carbon aerogel prepared by a single-step activation method) decreased slowly with increasing current density and its CV curve maintained a rectangular shape well even at a high scan rate of 500 mV/s. The enhanced electrochemical performance of ACA_S at a high current density was attributed to its low ionic resistance caused by the well-developed pore structure with appropriate pore size for easy moving of organic electrolyte ion. Therefore, it can be concluded that single-step activation method could be one of the efficient methods for preparation of nano-porous activated carbon aerogel electrode for high-power EDLC in organic electrolyte.

  3. Activated Carbon-Fly Ash-Nanometal Oxide Composite Materials: Preparation, Characterization, and Tributyltin Removal Efficiency

    Directory of Open Access Journals (Sweden)

    Olushola S. Ayanda

    2013-01-01

    Full Text Available The physicochemical properties, nature, and morphology of composite materials involving activated carbon, fly ash, nFe3O4, nSiO2, and nZnO were investigated and compared. Nature and morphology characterizations were carried out by means of scanning electron and transmission electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. Other physicochemical characterizations undertaken were CNH analysis, ash content, pH, point of zero charge, and surface area and porosity determination by BET. Experimental results obtained revealed that activated carbon, nSiO2, activated carbon-fly ash, activated carbon-fly ash-nFe3O4, activated carbon-fly ash-nSiO2, and activated carbon-fly ash-nZnO composite materials exhibited net negative charge on their surfaces while fly ash, nFe3O4, and nZnO possessed net positive charge on their surfaces. Relatively higher removal efficiency (>99% of TBT was obtained for all the composite materials compared to their respective precursors except for activated carbon. These composite materials therefore offer great potential for the remediation of TBT in wastewaters.

  4. Preparing electrochemical active hierarchically porous carbons for detecting nitrite in drinkable water

    KAUST Repository

    Ding, Baojun

    2016-01-13

    A class of hierarchically porous carbons were prepared by a facile dual-templating approach. The obtained samples were characterized by scanning electron microscopy, X-ray diffraction, Raman spectroscopy, Brunaner-Emmett-Teller measurement and electrochemical work station, respectively. The porous carbons could possess large specific surface area, interconnected pore structures, high conductivity and graphitizing degree. The resulting materials were used to prepare integrated modified electrodes. Based on the experimental results, the as-prepared hierarchically porous graphite (HPG) modified electrode showed the best electroactive performances toward the detection of nitrite with a detection limit of 8.1 × 10-3 mM. This HPG electrode was also repeatable and stable for 6 weeks. Moreover, this electrode was used for the determination of nitrite in drinkable water, and had acceptable recoveries. © The Royal Society of Chemistry 2016.

  5. Simple preparation of tungsten supported carbon nanoreactors for specific applications: Adsorption, catalysis and electrochemical activity

    Energy Technology Data Exchange (ETDEWEB)

    Mayani, Vishal J.; Mayani, Suranjana V.; Kim, Sang Wook, E-mail: swkim@dongguk.ac.kr

    2015-08-01

    Graphical abstract: - Highlights: • Tungsten carbon composites have shown great recognition in catalysis and electrochemistry. • W-carbon composites are prepared by template replication and W-doping on carbon cage. • Nanocomposites offer enormous assurance as adsorbent, electrode and heterogeneous catalyst. - Abstract: Porous carbon supported tungsten carbide nanoreactors, two sizes (∼25 and 170 nm), were designed using economical petroleum pitch residue followed by tungsten (W) doping. X-ray diffractions showed both carbon tungsten composites (CTC-25 and CTC-170) contained tungsten subcarbide (W{sub 2}C) and monocarbide (WC) as the major and minor crystalline phases, respectively. The present study provides a multiple perspective of carbon tungsten composites (CTCs) for methanol oxidation (as an electrode), adsorption (as an adsorbent) and degradation (as a solid catalyst) of methylene blue (MB). The operational electrodes were designed from both CTCs and used as a catalyst in an electrocatalysis process. The electrocatalysts exhibited high and stable catalytic performance (CTCE-25 > CTCE-170) in methanol electro-oxidation. The newly synthesized W-doped carbon nanoreactors were used successfully as an adsorbent for MB and a heterogeneous catalyst for MB oxidation. Ordered CTC-25 and CTC-170 exhibited dynamic MB adsorption within 15 min and complete oxidation of MB in 25–40 min. A synergetic effect between tungsten carbide and the carbon cage framework was noted.

  6. Preparation of High Surface Area Activated Carbon from Spent Phenolic Resin by Microwave Heating and KOH Activation

    Science.gov (United States)

    Cheng, Song; Zhang, Libo; Zhang, Shengzhou; Xia, Hongying; Peng, Jinhui

    2018-01-01

    The spent phenolic resin is as raw material for preparing high surface area activated carbon (HSAAC) by microwave-assisted KOH activation. The effects of microwave power, activation duration and impregnation ratio (IR) on the iodine adsorption capability and yield of HSAAC were investigated. The surface characteristics of HSAAC were characterized by nitrogen adsorption isotherms, FTIR, SEM and TEM. The operating variables were optimized utilizing the response surface methodology (RSM) and were identified to be microwave power of 700 W, activation duration of 15 min and IR of 4, corresponding to a yield of 51.25 % and an iodine number of 2,384 mg/g. The pore structure parameters of the HSAAC, i. e., Brunauer-Emmett-Teller (BET) surface area, total pore volume, and average pore diameter were estimated to be 4,269 m2/g, 2.396 ml/g and 2.25 nm, respectively, under optimum conditions. The findings strongly support the feasibility of microwave-assisted KOH activation for preparation of HSAAC from spent phenolic resin.

  7. Sorption study of methylene blue on activated carbon prepared from Jatropha curcas and Terminalia catappa seed coats

    Directory of Open Access Journals (Sweden)

    Ismaila Olalekan Saheed

    2016-12-01

    Full Text Available This research work targets the effectiveness of the prepared activated carbon from Jatropha curcas and Terminalia catappa seed coats for the sorption of methylene blue (MB from aqueous solution. The prepared Jatropha activated carbon (JAC and Terminalia activated carbon (TAC were characterised using Fourier transform infrared spectroscopy (FTIR, Scanning electron microscopy (SEM and Branauer- Emmett-Teller (BET surface area analysis. Effect of initial concentration, pH, contact time, adsorbent dose and temperature on the sorption experiments were studied and the adsorption capacity of these adsorbents were found to be 37.84 mg/g and 17.44 mg/g for methylene blue uptake by JAC and TAC respectively. The experimental data were analysed using Langmuir, Fruendlich, and Dubinin-Radushkevich isotherms. The data fitted best into Langmuir isotherm for Methylene blue-JAC and Methylene blue-TAC systems. The kinetic studies fitted into pseudo second order kinetics model. The process chemistry was exothermic.

  8. Preparation of Activated Carbon from Palm Shells Using KOH and ZnCl2 as the Activating Agent

    Science.gov (United States)

    Yuliusman; Nasruddin; Afdhol, M. K.; Amiliana, R. A.; Hanafi, A.

    2017-07-01

    Palm shell is a potential source of raw materials for the produce of activated carbon as biosorbent for quite large numbers. The purpose of this study is to produce activated carbon qualified Indonesian Industrial Standard (SNI), which will be used as biosorbent to purify the impurities in the off gas petroleum refinery products. Stages of manufacture of activated carbon include carbonization, activation of chemistry and physics. Carbonization of activated carbon is done at a temperature of 400°C followed by chemical activation with active agent KOH and ZnCl2. Then the physical activation is done by flowing N2 gas for 1 hour at 850°C and followed by gas flow through the CO2 for 1 hour at 850°C. Research results indicate that activation of the active agent KOH produce activated carbon is better than using the active agent ZnCl2. The use of KOH as an active agent to produce activated carbon with a water content of 13.6%, ash content of 9.4%, iodine number of 884 mg/g and a surface area of 1115 m2/g. While the use of ZnCl2 as the active agent to produce activated carbon with a water content of 14.5%, total ash content of 9.0%, iodine number 648 mg/g and a surface area of 743 m2/g.

  9. Removal of some metal ions by activated carbon prepared from Phaseolus aureus hulls

    Energy Technology Data Exchange (ETDEWEB)

    Rao, M. Madhava; Ramana, D.K.; Seshaiah, K. [Analytical and Environmental Chemistry Division, Department of Chemistry, Sri Venkateswara University, Tirupati 517 502 (India); Wang, M.C., E-mail: mcwang@cyut.edu.tw [Department of Environmental Engineering and Management, Chaoyang University of Technology, Wufong Township 41349, Taichung County, Taiwan (China); Chien, S.W. Chang [Department of Environmental Engineering and Management, Chaoyang University of Technology, Wufong Township 41349, Taichung County, Taiwan (China)

    2009-07-30

    Removal of lead [Pb(II)], zinc [Zn(II)], copper [Cu(II)], and cadmium [Cd(II)] from aqueous solutions using activated carbon prepared from Phaseolus aureus hulls (ACPAH), an agricultural waste was studied. The influence of various parameters such as effect of pH, contact time, adsorbent dose, and initial concentration of metal ions on the removal was evaluated by batch method. The removal of metal ions by ACPAH was pH dependent and the optimum pH values were 7.0, 8.0, 7.0 and 6.0 for Cu(II), Cd(II), Zn(II), and Pb(II), respectively. The sorption isotherms were studied using Langmuir, Freundlich, Dubinin-Radushkevich (D-R), and Temkin isotherm models. The maximum adsorption capacity values of ACPAH for metal ions were 21.8 mg g{sup -1} for Pb(II), 21.2 mg g{sup -1} for Zn(II), 19.5 mg g{sup -1} for Cu(II), and 15.7 mg g{sup -1} for Cd(II). The experiments demonstrated that the removal of metal ions followed the pseudo-second-order kinetic model. Desorption experiments were carried out using HCl solution with a view to regenerate the spent adsorbent and to recover the adsorbed metal ions.

  10. The Adsorption Efficiency of Chemically Prepared Activated Carbon from Cola Nut Shells by on Methylene Blue

    Directory of Open Access Journals (Sweden)

    Julius Ndi Nsami

    2013-01-01

    Full Text Available The adsorption of methylene blue from aqueous solution onto activated carbon prepared from cola nut shell has been investigated under batch mode. The influence of major parameters governing the efficiency of the process such as, solution pH, sorbent dose, initial concentration, and contact time on the removal process was investigated. The time-dependent experimental studies showed that the adsorption quantity of methylene blue increases with initial concentration and decreasing adsorbent dosage. The equilibrium time of 180 min was observed and maximum adsorption was favoured at pH 3.5. The dye removal using 0.1 g of adsorbent was more than 90%. This dosage (0.1 g was considered as the optimum dosage to remove methylene blue from aqueous solutions. The equilibrium adsorption data were analyzed by the Freundlich, Langmuir adsorption isotherm models. The kinetics of methylene blue solution was discussed by pseudo-first-order, pseudo-second-order, and Elovich models. The adsorption process follows the Elovich rate kinetic model, having a correlation coefficient in the range between 0.9811 and 1.

  11. Preparation of mesoporous carbon from fructose using zinc-based activators

    Directory of Open Access Journals (Sweden)

    Tutik Setianingsih

    2015-07-01

    Full Text Available Mesoporous carbons were synthesized from fructose using activators of zinc silicate (ZS, zinc borate (ZB, and zinc borosilicate (ZBS. The synthesis involves 3 steps, including caramelization of sugar, carbonization of caramel, and washing of carbon to separate the activator from the carbon. The solid products were characterized by N2 gas adsorption-desorption, X-ray diffraction, FTIR spectrophotometry, and Transmission Electron Microscopy. The pore characterizations of the carbons indicate that in ZBS system, ZB may have the role as mesopore size controller, whereas silica component may improve porosity created by ZB without changing the size. This role of ZB may be connected to it’s performance as catalyst of caramelization and it’s crystalinity, as supported by measurement of caramel intermediete and characterization of the activators with X-ray diffraction. The infrared spectra confirms that the carbons’s surfaces have C=O, C-O, and O-H functional groups. The XRD patterns of the carbons show that all activators create the turbotratic carbons.

  12. Preparation of Activated Carbon From Polygonum orientale Linn. to Remove the Phenol in Aqueous Solutions.

    Directory of Open Access Journals (Sweden)

    Jia Feng

    Full Text Available Phenol components are major industry contaminants of aquatic environment. Among all practical methods for removing phenol substances from polluted water, activated carbon absorption is the most effective way. Here, we have produced low-cost activated carbon using Polygonum orientale Linn, a wide spreading species with large biomass. The phenol adsorption ability of this activated carbon was evaluated at different physico-chemical conditions. Average equilibrium time for adsorption was 120 min. The phenol adsorption ability of the P. orientale activated carbon was increased as the pH increases and reached to the max at pH 9.00. By contrast, the ionic strength had little effect on the phenol absorption. The optimum dose for phenol adsorption by the P. orientale activated carbon was 20.00 g/L. The dominant adsorption mechanism of the P. orientale activated carbon was chemisorption as its phenol adsorption kinetics matched with the pseudo-second-order kinetics. In addition, the equilibrium data were fit to the Langmuir model, with the negative standard free energy and the positive enthalpy, suggesting that adsorption was spontaneous and endothermic.

  13. Preparation and characterization of activated carbon from castor de-oiled cake

    Directory of Open Access Journals (Sweden)

    Viviana M. Ospina-Guarín

    2014-01-01

    Full Text Available Biomass residues have been used to produce activated carbons. On this process, the activation method and the raw composition determine the properties as porosity and surface area of the charcoal. After the extraction of castor oil, there is a solid byproduct (cake of low added value, which was used in the production of activated carbon to add value to this waste. For this purpose two traditional methods were used, first, physical activation using as activating agents steam, CO2 and mixture of both, and additionally chemical activation using K2CO3 as the activating agent. Some activated carbons were characterized using N2 adsorption isotherms, BET surface areas varied between 255.98 (m2/g and 1218.43 (m2/g. By SEM and EDS analysis was possible to observe that materials obtained by the two types of activation are principally amorphous and morphological characteristics of the carbon obtained by physical activation are very different from those obtained by chemical activation. Finally, through impregnation of inorganic phases of Ni and Mo was revealed that the high dispersion characteristics, these carbonaceous materials will have potential to be used as catalyst support.

  14. Characterization of mesoporous carbon prepared from date stems by H{sub 3}PO{sub 4} chemical activation

    Energy Technology Data Exchange (ETDEWEB)

    Hadoun, H., E-mail: hhadoun@hotmail.com [Nuclear Research Center, 2 Bd Frantz Fanon, Algiers (Algeria); Laboratory of Reaction Genius, Mechanical and Processes Genius Faculty, University of Sciences and Technology Houari – Boumediene, BP n°32, El alia, bab ezzouar, 16111 Algiers (Algeria); Sadaoui, Z. [Laboratory of Reaction Genius, Mechanical and Processes Genius Faculty, University of Sciences and Technology Houari – Boumediene, BP n°32, El alia, bab ezzouar, 16111 Algiers (Algeria); Souami, N.; Sahel, D.; Toumert, I. [Nuclear Research Center, 2 Bd Frantz Fanon, Algiers (Algeria)

    2013-09-01

    The present work was focused on the determination of texture, morphology, crystanillity and oxygenated surface groups characteristics of an activated carbon prepared from date stems. Chemical activation of this precursor at different temperatures (450, 550 and 650 °C) was adopted using phosphoric acid as dehydrating agent at (2/1) impregnation ratio. Fourier transform infrared spectroscopy study was carried out to identify surface groups in date stems activated carbons. The microscopic structure was examined by nitrogen adsorption at 77 K. The interlayer spacing (d{sub 200} and d{sub 100}), stack height (L{sub c}), stack width (L{sub a}) and effective dimension L of the turbostratic crystallites (microcrystallite) in the date stems activated carbons were estimated from X-ray diffraction data (XRD). Results yielded a surface area, S{sub BET}, and total pore volume of 682, 1455, 1319 m{sup 2}/g and 0,343, 1,045 and 0.735 cm{sup 3}/g, for the carbon prepared at 450, 550 and 650 °C, respectively. Scanning electron microscopy exhibits a highly developed porosity which is in good agreement with the porous texture derived from gas adsorption data and these results confirm that the activated carbon is dominated by network of slit-shaped mesopores morphology and in some cases by varied micropores morphologies.

  15. Adsorption of Reactive Blue 171 from Aqueous Solution using Low Cost Activated Carbon Prepared from Agricultural Solid Waste: Albizia amara

    Directory of Open Access Journals (Sweden)

    K. Anitha

    2015-07-01

    Full Text Available The adsorption of Reactive Blue 171 (Reactive Dye from aqueous solution using activated carbon prepared from Albizia amara pod shell waste as an adsorbent have been carried out. The experimental adsorption data fitted reasonably well to Langmuir and Freundlich adsorption isotherms. Kinetic parameters as a function of Initial dye concentration have been calculated and the kinetic data were substituted in Pseudo First Order, Elovich and Pseudo Second order equations. A probable explanation is offered to account for the results of kinetic study. The thermodynamic parameter enthalpy change (∆H suggests the exothermic nature of absorption of Reactive Blue 171 onto activated Albizia amara pod shell waste carbon.

  16. Preparation and characterisation of raw chars and physically activated carbons derived from marine Posidonia oceanica (L.) fibres

    Energy Technology Data Exchange (ETDEWEB)

    Ncibi, M.C., E-mail: ncibi_mc@yahoo.com [Laboratoire de chimie, Institut Superieur Agronomique, Chott Meriem 4042, Sousse (Tunisia); Unite de Recherche ' Chimie Appliquee et Environnement' , EPAM Sousse 4000 (Tunisia); Laboratoire COVACHIMM, EA 3592 Universite des Antilles et de la Guyane, BP 250, 97157 Pointe a Pitre Cedex, Guadeloupe (France); Jeanne-Rose, V. [Laboratoire COVACHIMM, EA 3592 Universite des Antilles et de la Guyane, BP 250, 97157 Pointe a Pitre Cedex, Guadeloupe (France); Mahjoub, B. [Laboratoire de chimie, Institut Superieur Agronomique, Chott Meriem 4042, Sousse (Tunisia); Unite de Recherche ' Chimie Appliquee et Environnement' , EPAM Sousse 4000 (Tunisia); Jean-Marius, C. [Laboratoire COVACHIMM, EA 3592 Universite des Antilles et de la Guyane, BP 250, 97157 Pointe a Pitre Cedex, Guadeloupe (France); Lambert, J.; Ehrhardt, J.J. [Laboratoire de Chimie Physique et Microbiologie pour l' Environnement, UMR 7564 CNRS, Universites de Nancy, 405, rue de Vandoeuvre, F 56600 Villers-les-Nancy cedex (France); Bercion, Y. [Groupe de Technologie des Surfaces et Interfaces (GTSI), EA 2432, Faculte des Sciences Exactes et Naturelles, Universite des Antilles et de la Guyane, BP 250, 97157 Pointe a Pitre Cedex, Guadeloupe (France); Seffen, M. [Laboratoire de chimie, Institut Superieur Agronomique, Chott Meriem 4042, Sousse (Tunisia); Unite de Recherche ' Chimie Appliquee et Environnement' , EPAM Sousse 4000 (Tunisia); Gaspard, S. [Laboratoire COVACHIMM, EA 3592 Universite des Antilles et de la Guyane, BP 250, 97157 Pointe a Pitre Cedex, Guadeloupe (France)

    2009-06-15

    Industrial valorisation of low cost and renewable biomass as raw precursor of activated carbon for environmental applications is an interesting alternative to costly commercial activated carbons. In this study, the possible use of Mediterranean, Posidonia oceanica fibrous biomass, as a precursor for chars and physically activated carbons, is investigated. Firstly, the raw marine material was chemically and biochemically characterised throughout dry-basis elemental, X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) analysis. Then, several P. oceanica chars were prepared and characterised under different pyrolysis times and temperatures. In addition, physically activated carbons (PACs) were produced via water steam flow under various activation periods. The results showed that the pyrolysis induces the creation of pores at different levels with respect to the involved temperature. Thereafter, the physical activation tends to enhance the development of the porous structure. In that issue, the performed Brunauer-Emmett-Teller (BET) and Barrett-Joiner-Halenda (BJH) analysis revealed that the prepared PACs have a mainly mesoporous inner morphology with a varying fraction of micropores.

  17. Preparation and characterization of activated carbon derived from the thermo-chemical conversion of chicken manure.

    Science.gov (United States)

    Koutcheiko, S; Monreal, C M; Kodama, H; McCracken, T; Kotlyar, L

    2007-09-01

    Physico-chemical properties of a bioorganic char were modified by pyrolysis in the presence of NaOH, and with subsequent physical activation of carbonaceous species with CO2 a value-added activated carbon was fabricated. Bioorganic char is produced as a co-product during the production of bio-fuel from the pyrolysis of chicken litter. Untreated char contains approximately 37 wt% of C and approximately 43-45 wt% of inorganic minerals containing K, Ca, Fe, P, Cu, Mg, and Si. Carbonization and chemical activation of the char at 600 degrees C in the presence of NaOH in forming gas (4% H2 balanced with Ar) produced mainly demineralized activated carbon having BET (Brunauer, Emmett, and Teller) surface area of 486 m2/g and average pore size of 2.8 nm. Further physical activation with CO2 at 800 degrees C for 30 min resulted in activated carbon with BET surface area of 788 m2/g and average pore size of 2.2 nm. The mineral content was 10 wt%. X-ray photoelectron spectroscopy (XPS) indicated that the latter activation process reduced the pyrrolic- and/or pyridonic-N, increased pyridinic-N and formed quaternary-N at the expense of pyrrolic- and/or pyridonic-N found in the untreated char.

  18. Environmental impact associated with activated carbon preparation from olive-waste cake via life cycle assessment.

    Science.gov (United States)

    Hjaila, K; Baccar, R; Sarrà, M; Gasol, C M; Blánquez, P

    2013-11-30

    The life cycle assessment (LCA) environmental tool was implemented to quantify the potential environmental impacts associated with the activated carbon (AC) production process from olive-waste cakes in Tunisia. On the basis of laboratory investigations for AC preparation, a flowchart was developed and the environmental impacts were determined. The LCA functional unit chosen was the production of 1 kg of AC from by-product olive-waste cakes. The results showed that impregnation using H3PO4 presented the highest environmental impacts for the majority of the indicators tested: acidification potential (62%), eutrophication (96%), ozone depletion potential (44%), human toxicity (64%), fresh water aquatic ecotoxicity (90%) and terrestrial ecotoxicity (92%). One of the highest impacts was found to be the global warming potential (11.096 kg CO2 eq/kg AC), which was equally weighted between the steps involving impregnation, pyrolysis, and drying the washed AC. The cumulative energy demand of the AC production process from the by-product olive-waste cakes was 167.63 MJ contributed by impregnation, pyrolysis, and drying the washed AC steps. The use of phosphoric acid and electricity in the AC production were the main factors responsible for the majority of the impacts. If certain modifications are incorporated into the AC production, such as implementing synthesis gas recovery and reusing it as an energy source and recovery of phosphoric acid after AC washing, additional savings could be realized, and environmental impacts could be minimized. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Preparation of activated carbon hollow fibers from ramie at low temperature for electric double-layer capacitor applications.

    Science.gov (United States)

    Du, Xuan; Zhao, Wei; Wang, Yi; Wang, Chengyang; Chen, Mingming; Qi, Tao; Hua, Chao; Ma, Mingguo

    2013-12-01

    Activated carbon hollow fibers (ACHFs) with high surface area were prepared from inexpensive, renewable ramie fibers (RFs) by a single-step activation method under lower temperature than that of other reports. The effects of activation conditions on the pore structure and turbostratic structure of ACHFs were investigated systematically. The results show that ACHFs surface area decreased but micropore volume and conductivity increased as the increase of activation temperature and activation time. The electrochemical measurements of supercapacitors fabricated from these ACHFs electrodes reveal that the electrochemical properties improved with the enhancing of activation degree. However, too high activation temperature can make the ion diffusion resistance increase. It suggests that pore structure and conductivity are as important as surface area to decide the electrochemical performances of ACHFs electrode materials. A maximum capacity of 287 F g(-1) at 50 mA g(-1) was obtained for the ACHFs electrode prepared under suitable conditions. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Fast and efficient adsorption of methylene green 5 on activated carbon prepared from new chemical activation method.

    Science.gov (United States)

    Tran, Hai Nguyen; You, Sheng-Jie; Chao, Huan-Ping

    2017-03-01

    Activated carbon (AC) was synthesized from golden shower (GS) through a new chemical activation process. The three-stage process comprised (1) hydrothermal carbonization of GS to produce hydrochar, (2) pyrolysis of hydrochar to produce biochar, and (3) subsequent chemical activation of biochar with K 2 CO 3 to obtain GSHBAC. The traditional synthesis processes (i.e., one-stage and two-stage) were also examined for comparison. In the one-stage process, GS that was impregnated with K 2 CO 3 was directly pyrolyzed (GSAC), and the two-stage process consisted of (1) pyrolytic or hydrothermal carbonization to produce biochar or hydrochar and (2) subsequent chemical activation was defined as GSBAC and GSHAC, respectively. The synthesized ACs were characterized by scanning electron microscope, Brunauer-Emmett-Teller (BET) surface area analysis, Fourier transform infrared spectrometry, point zero charge, and Boehm titration. The adsorption results demonstrated that the MG5 adsorption process was not remarkably affected by neither the solution pH (2.0-10) nor ionic strength (0-0.5 M NaCl). Kinetic studies showed that the adsorption equilibrium was quickly established, with a low activation energy required for adsorption (Ea; 3.30-27.8 kJ/mol), and the ACs removed 50-73% of the MG5 concentration from solution within 01 min. Desorption studies confirmed the adsorption was irreversible. Thermodynamic experiments suggested that the MG5 adsorption was spontaneous (-ΔG°) and endothermic (+ΔH°), and increased the randomness (+ΔS°) in the system. Although the specific surface areas of the ACs followed the order GSAC (1,413) > GSHAC (1,238) > GSHBAC (903) > GSBAC (812 m 2 /g), the maximum adsorption capacities determined from the Langmuir model (Q o max ) at 30 °C exhibited the following order: GSHBAC (531) > GSAC (344) > GSHAC (332) > GSBAC (253 mg/g). Oxygenation of the ACs' surface through a hydrothermal process with acrylic acid resulted in a decrease in

  1. Characterization and Properties of Activated Carbon Prepared from Tamarind Seeds by KOH Activation for Fe(III) Adsorption from Aqueous Solution.

    Science.gov (United States)

    Mopoung, Sumrit; Moonsri, Phansiri; Palas, Wanwimon; Khumpai, Sataporn

    2015-01-01

    This research studies the characterization of activated carbon from tamarind seed with KOH activation. The effects of 0.5 : 1-1.5 : 1 KOH : tamarind seed charcoal ratios and 500-700°C activation temperatures were studied. FTIR, SEM-EDS, XRD, and BET were used to characterize tamarind seed and the activated carbon prepared from them. Proximate analysis, percent yield, iodine number, methylene blue number, and preliminary test of Fe(III) adsorption were also studied. Fe(III) adsorption was carried out by 30 mL column with 5-20 ppm Fe(III) initial concentrations. The percent yield of activated carbon prepared from tamarind seed with KOH activation decreased with increasing activation temperature and impregnation ratios, which were in the range from 54.09 to 82.03 wt%. The surface functional groups of activated carbon are O-H, C=O, C-O, -CO3, C-H, and Si-H. The XRD result showed high crystallinity coming from a potassium compound in the activated carbon. The main elements found in the activated carbon by EDS are C, O, Si, and K. The results of iodine and methylene blue adsorption indicate that the pore size of the activated carbon is mostly in the range of mesopore and macropore. The average BET pore size and BET surface area of activated carbon are 67.9764 Å and 2.7167 m(2)/g, respectively. Finally, the tamarind seed based activated carbon produced with 500°C activation temperature and 1.0 : 1 KOH : tamarind seed charcoal ratio was used for Fe(III) adsorption test. It was shown that Fe(III) was adsorbed in alkaline conditions and adsorption increased with increasing Fe(III) initial concentration from 5 to 20 ppm with capacity adsorption of 0.0069-0.019 mg/g.

  2. Preparation of activated carbon from molasses-to-ethanol process waste vinasse and its performance as adsorbent material.

    Science.gov (United States)

    Kazak, Omer; Ramazan Eker, Yasin; Bingol, Haluk; Tor, Ali

    2017-10-01

    Herein, the preparation of activated carbon from waste vinasse by using hydrothermal H 2 O 2 oxidation combined with a two-step pyrolysis process has been described for the first time as a new utilization approach for the waste vinasse. The characterization studies were performed by TGA, FT-IR, Raman spectroscopy, SEM-EDX and gas adsorption measurements. The approach generated a microporous activated carbon with high specific surface area (989m 2 /g) from waste vinasse. After simple experiments on various dye solutions, adsorption performance of the activated carbon was specifically studied on the methylene blue solution as functions of solution pH, contact time, adsorbent amount and reusability. The obtained activated carbon had a higher Langmuir adsorption capacity towards methylene blue (909.091±31.900mg/g) than many other adsorbents and it is reusable for at least six cycles. The adsorption performance of the obtained activated carbon was also evaluated using both simulated and real dye-house effluents. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Increase of porosity by combining semi-carbonization and KOH activation of formaldehyde resins to prepare high surface area carbons for supercapacitor applications

    Science.gov (United States)

    Heimböckel, Ruben; Kraas, Sebastian; Hoffmann, Frank; Fröba, Michael

    2018-01-01

    A series of porous carbon samples were prepared by combining a semi-carbonization process of acidic polymerized phenol-formaldehyde resins and a following chemical activation with KOH used in different ratios to increase specific surface area, micropore content and pore sizes of the carbons which is favourable for supercapacitor applications. Samples were characterized by nitrogen physisorption, powder X-ray diffraction, Raman spectroscopy and scanning electron microscopy. The results show that the amount of KOH, combined with the semi-carbonization step had a remarkable effect on the specific surface area (up to SBET: 3595 m2 g-1 and SDFT: 2551 m2 g-1), pore volume (0.60-2.62 cm3 g-1) and pore sizes (up to 3.5 nm). The carbons were tested as electrode materials for electrochemical double layer capacitors (EDLC) in a two electrode setup with tetraethylammonium tetrafluoroborate in acetonitrile as electrolyte. The prepared carbon material with the largest surface area, pore volume and pore sizes exhibits a high specific capacitance of 145.1 F g-1 at a current density of 1 A g-1. With a high specific energy of 31 W h kg-1 at a power density of 33028 W kg-1 and a short time relaxation constant of 0.29 s, the carbon showed high power capability as an EDLC electrode material.

  4. Pyrolysis polygeneration of pine nut shell: Quality of pyrolysis products and study on the preparation of activated carbon from biochar.

    Science.gov (United States)

    Chen, Dengyu; Chen, Xiaojuan; Sun, Jun; Zheng, Zhongcheng; Fu, Kexin

    2016-09-01

    A lab-scale pyrolysis reactor was utilized to investigate the effect of pyrolysis temperature (300-700°C) on the yield, quality, and energy distribution of products issued from the pyrolysis polygeneration of pine nut shells. Afterward, activated carbon was prepared from biochar using the steam activation method. Pyrolysis temperatures ranging from 500 to 600°C were found to be optimal in inducing products with improved properties, such as higher heating values of non-condensable gas, lower water content and elevated heating values of bio-oil, and substantial fixed carbon content and greater specific surface area of biochar. In addition, it was noticed that the activation conditions had a significant effect on the yield and adsorption performance of the activated carbon. As a result, activated carbon with elevated specific surface area reaching 1057.8m(2)/g was obtained at the optimal conditions of 850°C activation temperature, 80min activation time, and 1.5 steam/biochar ratio. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Facile preparation of well-combined lignin-based carbon/ZnO hybrid composite with excellent photocatalytic activity

    Science.gov (United States)

    Wang, Huan; Qiu, Xueqing; Liu, Weifeng; Yang, Dongjie

    2017-12-01

    In this work, a novel lignin-based carbon/ZnO (LC/ZnO) hybrid composite with excellent photocatalytic performance was prepared through a convenient and environment friendly method using alkali lignin (AL) as carbon source. The morphological, microstructure and optical properties of the as-prepared LC/ZnO hybrid composite was characterized with scanning electron microscope (SEM), X-ray diffraction (XRD), Raman and UV-vis. The resulting LC/ZnO hybrid is composed of highly dispersed ZnO nanoparticles embedded on a lignin-based carbon nanosheet, showing excellent photogenerated electrons and holes separation and migration efficiency. The photocatalytic activity of LC/ZnO was much higher than the pure ZnO. The LC/ZnO hybrid composite showed different photocatalytic mechanism for degradation of negative methyl orange (MO) and positive Rhodamine B (RhB). It showed that h+ was the main photocatalytic active group during the degradation of MO, ·O2- and ·OH were the photocatalytic active groups during degradation of RhB. This reported photocatalyst with selective degradation of positive and negative organic dyes may have a great application prospect for photoelectric conversion and catalytic materials. Results of this work were of practical importance for high-valued utilization of lignin for carbon materials.

  6. Preparing to Capture Carbon

    National Research Council Canada - National Science Library

    Daniel P. Schrag

    2007-01-01

    .... Scientific and economic challenges still exist, but none are serious enough to suggest that carbon capture and storage will not work at the scale required to offset trillions of tons of carbon...

  7. Preparation and characterization of activated carbon from cotton stalk by microwave assisted chemical activation-Application in methylene blue adsorption from aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Deng Hui, E-mail: dengh@yahoo.com.cn [Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan, School of Chemistry and Chemical Engineering, Shihezi University, Shihezi 832003, Xinjiang (China); Yang Le [Agriculture college, Shihezi University, Shihezi 832003, Xinjiang (China); Tao Guanghui; Dai Jiulei [Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan, School of Chemistry and Chemical Engineering, Shihezi University, Shihezi 832003, Xinjiang (China)

    2009-07-30

    The activated carbon prepared from cotton stalk with ZnCl{sub 2} as activation was investigated under microwave radiation. Effects on the yield and adsorption capacities of activated carbon were evaluated then, such as, microwave power, microwave radiation time and the impregnation ratio of ZnCl{sub 2}. It indicated that the optimum conditions were as follows: microwave power of 560 W, microwave radiation time of 9 min and the impregnation ratio of ZnCl{sub 2} was 1.6 g/g. Iodine number, amount of methylene blue adsorption and the yield of activated carbon prepared under optimum conditions were 972.92 mg/g, 193.50 mg/g and 37.92%, respectively. Laboratory prepared activated carbons were characterized by pH{sub ZPC}, SEM, FT-IR, S{sub BET} and pore structural parameters. Then they were used as adsorbent for the removal of methylene blue from aqueous solutions under varying conditions of initial concentration, carbon dosage and pH. It indicated that Langmuir isotherm was fitter than Freundlich isotherm and Temkin isotherm.

  8. Preparation of green alga-based activated carbon with lower impregnation ratio and less activation time by potassium tartrate for adsorption of chloramphenicol.

    Science.gov (United States)

    Zhu, Xiuzhen; Gao, Yuan; Yue, Qinyan; Kan, Yujiao; Kong, Wenjia; Gao, Baoyu

    2017-11-01

    Potassium tartrate (C 4 H 6 K 2 O 7 ) was utilized as a novel activating agent to prepare activated carbon with relatively high specific surface area by using less activating agent and activation time from marine waste-green alga (Enteromorpha prolifera) for the first time. The influences of activation temperature, impregnation ratio and activation time on the pore structure were investigated to obtain the optimum conditions (activation temperature: 700°C, impregnation ratio: 1:1, and activation time: 30min). Meanwhile, the activation temperature was evaluated to be the essential factor that dominated the form of pore structure in activated carbon. The green alga-based activated carbon that was prepared under optimum conditions has shown the high surface area of 1692m 2 /g and total pore volume of 1.22cm 3 /g, which could be used as an effective adsorbent to remove chloramphenicol. The thermodynamic data of chloramphenicol were well fitted by Langmuir isotherm model and the green alga-based activated carbon has showed high adsorption capacity of 709.2mg/g towards chloramphenicol. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Adsorption of U(VI) ions from aqueous solutions by activated carbon prepared from Antep pistachio (Pistacia vera L.) shells

    Energy Technology Data Exchange (ETDEWEB)

    Donat, Ramazan [Pamukkale Univ., Denizli (Turkey). Dept. of Chemistry; Erden, Kadriye Esen [Pamukkale Univ., Kinikli-Denizli (Turkey). Denizli Vocational School of Technical Sciences

    2017-08-01

    Antep pistachio (Pistacia vera L.) shells an abundant and low cost natural resource in Turkey was used to prepare activated carbon by physiochemical activation and carbon dioxide (CO{sub 2}) atmosphere as the activating agents at 700 C for 2 h. The adsorption equilibrium of U(VI) from aqueous solutions on such carbon has been studied using a batch system. The parameters that affect the U(VI) adsorption, such as particle size of adsorbent, contact time, of pH of the solution, and temperature, have been investigated and conditions have also been optimized. The equilibrium data for U(VI) ions' adsorption onto activated carbon well fitted to the Langmuir equation, with a maximum monolayer adsorption capacity of 8.68 mg/g, The Freundlich and Dubinin-Radushkevich (D-R) isotherms have been applied and the data correlated well with Freundlich model and that the adsorption is physical in nature (E{sub a}=15.46 kJ/mol). Thermodynamic parameters [ΔH{sub s}=11.33 kJ/mol, ΔS=0.084 kJ/molK, ΔG (293.15 K)=-13.29 kJ/mol] showed the endothermic heat of adsorption and the feasibility of the process.

  10. The investigation of copper-based impregnated activated carbons prepared from water-soluble materials for broad spectrum respirator applications.

    Science.gov (United States)

    Smith, J W H; Westreich, P; Abdellatif, H; Filbee-Dexter, P; Smith, A J; Wood, T E; Croll, L M; Reynolds, J H; Dahn, J R

    2010-08-15

    The preparation of impregnated activated carbons (IACs) from aqueous, copper-containing solutions for broad spectrum gas filtration applications is studied here. Several samples were studied to determine the effect that impregnant loading, impregnant distribution and impregnant recipe had on the overall performance. Dynamic flow testing was used to determine the gas filtration capacity of the IAC samples versus a variety of challenge gases. X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX) were used to characterize the impregnant distribution on the carbon as a function of impregnant loading. Oven tests were performed to determine the thermal stability of the IAC samples exposed to elevated temperatures. The role impregnant distribution plays in gas filtration capacity and the overall performance of the IAC samples is discussed. The IAC samples prepared in this work were found to have gas filtration capacities as good as or better than broad spectrum respirator carbon samples prepared from the patent literature. IACs impregnated with an aqueous 2.4 M Cu(NO(3))(2)/0.04 M H(3)PO(4).12MoO(3)/4M HNO(3) solution that were heated to 200 degrees C under argon were found to have the best overall performance of the samples studied in this work. Copyright 2010 Elsevier B.V. All rights reserved.

  11. Advances in preparation of modified activated carbon and its applications in the removal of chromium (VI) from aqueous solutions

    Science.gov (United States)

    Deng, Z. L.; Liang, M. N.; Li, H. H.; Zhu, Z. J.

    2016-08-01

    The wastewater in which Cr(VI) is not fully treated has drawn environment researchers’ attention increasingly, due to its environmental pollution and harms to human health. Thus a high efficiency of modified activated carbon (MAC) to remove Cr(VI) has become one of the hot topics among environmental material research. This paper introduces the modification methods from the physical structure features and chemical properties of the activated carbon (AC) surface. At the same time, it briefly analyses the chemical characteristics of Cr(VI) in aqueous solutions, and on the basis of the aforementioned introduces the modification methods of the surface chemical characteristics of AC, such as: oxidation modification, reduction modification, loaded metal modification, and microwave modification. Combining studies on removing Cr(VI) from aqueous solutions by MAC in recent years, this paper anticipates the new trends of preparing MAC and the points in absorption research, offering some suggestions for future studies.

  12. Textural and chemical characterization of activated carbon prepared from shell of african palm (Elaeis guineensis by chemical activation with CaCl2 and MgCl2

    Directory of Open Access Journals (Sweden)

    Sergio Acevedo

    2015-09-01

    Full Text Available Activated carbons through chemical activation of African palm shells (Elaeis guineensis with magnesium chloride and calcium chloride solutions at different concentrations were obtained. The prepared materials were characterized textural and chemically. The results show that activated carbons with higher values of surface area and pore volume are obtained when solutions with lower concentrations of the activating agent are used. The obtained activated carbons have surface areas and pore volumes with values between 10 and 501 m2 /g and 0.01 and 0.29 cm3 /g respectively. Immersion enthalpies values of solids in water were between -14.3 and -32.8 J/g and benzene between -13.9 and -38.6 J/g. Total acidity and basicity of the activated carbons had values between 23 and 262 μmol/g 123 and 1724 μmol/g respectively. pH at the point of zero charge was also determined with values between 4.08 and 9.92 for set of activated carbons . The results show that activation with CaCl2 and MgCl2 salts produce activated carbons with pores in the range of mesopores for facilitate entry of the adsorbate into the materials.

  13. Adsorption studies on the removal of COD and BOD from treated sewage using activated carbon prepared from date palm waste.

    Science.gov (United States)

    Nayl, Abd ElAziz A; Elkhashab, Reda A; El Malah, Tamer; Yakout, Sobhy M; El-Khateeb, Mohamed A; Ali, Mahmoud M S; Ali, Hazim M

    2017-08-10

    In this work, the adsorption of chemical oxygen demand (COD) and biological oxygen demand (BOD) from treated sewage with low-cost activated carbon prepared from date palm shell waste by chemical activation method was studied. Different parameters affecting the adsorption process such as carbon dose, pH, contact time, agitation rate, and temperature were studied. Adsorption equilibrium was attained after 150 min at pH 6.0 with agitation rate of 400 rpm at 25 °C. The results showed that COD removal percentage of 95.4 and 92.8% for BOD was obtained with carbon dosage of 0.1 g/100 ml of solution. The experimental batch equilibrium results follow linear, Langmuir, and Freundlich isotherm models. The experimental data was fitted to a pseudo-second-order kinetics model controlled by pore diffusion. Thermodynamic parameter values of ΔH (0), ΔG (0), and ΔS (0) were calculated. The obtained data indicated that the adsorption was spontaneous, endothermic nature and reflects an increased randomness and degree of disorderliness at the activated carbon/sewage interface during the adsorption process investigated in this study. Concentrations of different impurities were reduced to very small value by investigated adsorption process.

  14. Simple preparation of rice husk activated carbon (RHAC) and applications for laundry and methylene blue wastewater treatment

    Science.gov (United States)

    Riyanto, Astuti, Rury; Mukti, Bayu Ismoyo

    2017-12-01

    The research of laundry and methylene blue wastewater treatment has been done using Rice Husk Activated Carbon (RHAC). Preparation of RHAC was doing by the furnace with temperature activating at 400 °C. RHAC preparation results were used for laundry and methylene blue wastewater treatment. In this study was also conducted the time and the weight of RHAC variation. 100 mL of laundry wastewater was mixed by RHAC powder as much 2 g then stirred and filtered. The performance of RHAC can be seen at the COD before and after treatment. The results showed that the time and weight of a good condition for methylene blue wastewater treatment are 60 minute and 7 g RHAC. The percentage of COD reduction for laundry wastewater treatment at 30 minutes is 79.39%. Meanwhile, the best percentage of COD reduction is 90.19% using RHAC with weight is 7 g.

  15. Adsorptive removal of phenol from aqueous solutions on activated carbon prepared from tobacco residues: Equilibrium, kinetics and thermodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Kilic, Murat; Apaydin-Varol, Esin [Department of Chemical Engineering, Anadolu University, Eskisehir 26470 (Turkey); Puetuen, Ayse E., E-mail: aeputun@anadolu.edu.tr [Department of Chemical Engineering, Anadolu University, Eskisehir 26470 (Turkey)

    2011-05-15

    This study consists of producing high surface area activated carbon from tobacco residues by chemical activation and its behavior of phenol removal from aqueous solutions. K{sub 2}CO{sub 3} and KOH were used as chemical activation agents and three impregnation ratios (50, 75 and 100 wt.%) were applied on biomass. Maximum BET surface areas of activated carbons were obtained from impregnation with 75 wt.% of K{sub 2}CO{sub 3} and 75 wt.% of KOH as 1635 and 1474 m{sup 2}/g, respectively. Optimum adsorption conditions were determined as a function of pH, adsorbent dosage, initial phenol concentration, contact time and temperature of solution for phenol removal. To describe the equilibrium isotherms the experimental data were analyzed by the Langmuir, Freundlich, Dubinin-Radushkevich (D-R) and Temkin isotherm models. Pseudo-first order, pseudo-second order and intraparticle diffusion kinetic models were used to find out the kinetic parameters and mechanism of adsorption process. The thermodynamic parameters such as {Delta}G{sup o}, {Delta}H{sup o} and {Delta}S{sup o} were calculated for predicting the nature of adsorption. According to the experimental results, activated carbon prepared from tobacco residue seems to be an effective, low-cost and alternative adsorbent precursor for the removal of phenol from aqueous solutions.

  16. Preparation of mesoporous activated carbon from palm-date pits: optimization study on removal of bentazon, carbofuran, and 2,4-D using response surface methodology.

    Science.gov (United States)

    Salman, J M; Abid, F M

    2013-01-01

    Palm-date pits were used to prepare activated carbon by physiochemical activation method, which consisted of potassium hydroxide (KOH) treatment and carbon dioxide (CO(2)) gasification. The effects of variable parameters, activation temperature, activation time and chemical impregnation ratios (KOH: char by weight) on the preparation of activated carbon and for removal of pesticides: bentazon, carbofuran and 2,4-dichlorophenoxyacetic acid (2,4-D) were investigated. Based on the central composite design (CCD), two factor interaction (2FI) and quadratic models were respectively employed to correlate the effect of variable parameters on the preparation of activated carbon used for removal of pesticides with carbon yield. From the analysis of variance (ANOVA), the most influential factor on each experimental design response was identified. The optimum conditions for preparing activated carbon from palm-date pits were found to be: activation temperature of 850 °C, activation time of 3 h and chemical impregnation ratio of 3.75, which resulted in an activated carbon yield of 19.5% and bentazon, carbofuran, and 2,4-D removal of 84, 83, and 93%, respectively.

  17. Adsorption of methylene blue onto activated carbon prepared from Lupinus Albus

    Directory of Open Access Journals (Sweden)

    Bağcı Safiye

    2016-01-01

    Full Text Available The adsorption of methylene blue (MB from synthetic aqueous solutions in batch experiments using Lupinus Albus-activated carbon (LAAC by chemical activation with zinc chloride was investigated. Prior to adsorption experiments, surface/physical properties of LAAC were determined using Scanning Electron Microscopy, Fourier transform infrared Spectroscopy and nitrogen adsorption isotherm. In the adsorption experiments, effects of adsorption time, solution pH, MB concentration and amount of LAAC were investigated. The isotherm and kinetic parameters were used to describe the experimental data. The BET surface area was 1254 m2/g while its total pore volume was found to be 0.484 cm3/g. Maximum adsorption capacity occurred at solution pH value 10 and was recorded as 109.89 mg/g. Adsorption data were modeled using Langmuir, Freundlich and Temkin adsorption isotherms. Langmuir isotherm and pseudo-second-order models fit to the process and reaction kinetics correspondingly.

  18. Preparation and Characterization of Activated Carbon from Iraqi Khestawy Date Palm

    Directory of Open Access Journals (Sweden)

    Falah H. Hussein

    2015-01-01

    Full Text Available This work includes a synthesis of three types of the activated carbon (AC from three different positions from the same Iraqi Khestawy date palm. These three positions are the palm fronds (AC1, the date palm seeds (AC2, and the palm fiber (AC3. These three types of AC were synthesized by a physiochemical activation method using the same activator which was H3PO4. These materials were investigated using different techniques such as Fourier transform infrared spectroscopy (FTIR and scanning electron microscopy (SEM. The adsorption activity of the synthesized AC samples was investigated by following the removal of both Bismarck brown G (BBG and reactive yellow dye 145 (RY145. Both the kinetics of adsorption and the removal percentage of these dyes were investigated from the batch tests in this study. Different reaction parameters and conditions for adsorption processes were investigated. Also an investigation of both Langmuir and Freundlich adsorption isotherms was considered. The different physical properties of these materials were undertaken such as the point zero charges of the synthesized samples (PZCs, the percentage of humidity, and the adsorption capacity also being investigated. The activity of these materials in the removal of BBG from the aqueous solution was as follows: AC1>AC2>AC3.

  19. Elucidation of the naproxen sodium adsorption onto activated carbon prepared from waste apricot: Kinetic, equilibrium and thermodynamic characterization

    Energy Technology Data Exchange (ETDEWEB)

    Onal, Y. [Inonu University, Faculty of Engineering, Department of Chemical Engineering, 44280 Malatya (Turkey)], E-mail: yonal@inonu.edu.tr; Akmil-Basar, C.; Sarici-Ozdemir, C. [Inonu University, Faculty of Engineering, Department of Chemical Engineering, 44280 Malatya (Turkey)

    2007-09-30

    In this study, activated carbon (WA11Zn5) was prepared from waste apricot, which is waste in apricot plants in Malatya, by chemical activation with ZnCl{sub 2}. BET surface area of activated carbon is determined as 1060 m{sup 2}/g. The ability of WA11Zn5, to remove naproxen sodium from effluent solutions by adsorption has been studied. Equilibrium isotherms for the adsorption of naproxen sodium on activated carbon were measured experimentally. Results were analyzed by the Langmiur, Freundlich equation using linearized correlation coefficient at 298 K. The characteristic parameters for each isotherm have been determined. Langmiur equation is found to best represent the equilibrium data for naproxen sodium-WA11Zn5 systems. The monolayer adsorption capacity of WA11Zn5 for naproxen sodium was found to be 106.38 mg/g at 298 K. The process was favorable and spontaneous. The kinetics of adsorption of naproxen sodium have been discussed using three kinetic models, i.e., the pseudo first-order model, the pseudo second-order model, the intraparticle diffusion model. Kinetic parameters and correlation coefficients were determined. It was shown that the pseudo second-order kinetic equation could describe the adsorption kinetics for naproxen sodium onto WA11Zn5. The thermodynamic parameters, such as {delta}G{sup o}, {delta}S{sup o} and {delta}H{sup o}, were calculated. The thermodynamics of naproxen sodium-WA11Zn5 system indicates endothermic process.

  20. Preparation and photocatalytic activity of cuprous oxide/carbon nanofibres composite films

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yuanqian; Liu, Lin; Cai, Yurong; Chen, Jianjun [The Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Ministry of Education, College of Materials and Textiles, Zhejiang Sci-Tech University, Xiasha Higher Education Park, Hangzhou 310018 (China); Yao, Juming, E-mail: yaoj@zstu.edu.cn [The Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Ministry of Education, College of Materials and Textiles, Zhejiang Sci-Tech University, Xiasha Higher Education Park, Hangzhou 310018 (China)

    2013-04-01

    Cuprous oxide (Cu{sub 2}O) nanocrystals have been successfully synthesized using copper acetate as precursors via a polyol process. The as-synthesized products were easily deposited on the surface of carbon nanofibres (CNFs) and then were characterized through XRD, FESEM, TEM and FTIR, etc. The photocatalytic performance of these composite films was evaluated using methyl orange as a model organic compound under visible light irradiation. Results showed that the shape of Cu{sub 2}O nanparticles could be changed from irregular nanoparticle to cubic, flower-like particle assembled by Cu{sub 2}O nanocubes with the change of the reaction conditions. All of these Cu{sub 2}O/CNFs composite films showed the satisfied photocatalytic activity to methyl orange even after 3 cycles of degradation experiment due to the protectable function of carbon fibre films to the Cu{sub 2}O nanocrystals. The Cu{sub 2}O/CNFs composite films may offer a feasible method for the potential application of Cu{sub 2}O nanocrystals in the treatment of organic contamination.

  1. Characterization and Properties of Activated Carbon Prepared from Tamarind Seeds by KOH Activation for Fe(III) Adsorption from Aqueous Solution

    Science.gov (United States)

    Mopoung, Sumrit; Moonsri, Phansiri; Palas, Wanwimon; Khumpai, Sataporn

    2015-01-01

    This research studies the characterization of activated carbon from tamarind seed with KOH activation. The effects of 0.5 : 1–1.5 : 1 KOH : tamarind seed charcoal ratios and 500–700°C activation temperatures were studied. FTIR, SEM-EDS, XRD, and BET were used to characterize tamarind seed and the activated carbon prepared from them. Proximate analysis, percent yield, iodine number, methylene blue number, and preliminary test of Fe(III) adsorption were also studied. Fe(III) adsorption was carried out by 30 mL column with 5–20 ppm Fe(III) initial concentrations. The percent yield of activated carbon prepared from tamarind seed with KOH activation decreased with increasing activation temperature and impregnation ratios, which were in the range from 54.09 to 82.03 wt%. The surface functional groups of activated carbon are O–H, C=O, C–O, –CO3, C–H, and Si–H. The XRD result showed high crystallinity coming from a potassium compound in the activated carbon. The main elements found in the activated carbon by EDS are C, O, Si, and K. The results of iodine and methylene blue adsorption indicate that the pore size of the activated carbon is mostly in the range of mesopore and macropore. The average BET pore size and BET surface area of activated carbon are 67.9764 Å and 2.7167 m2/g, respectively. Finally, the tamarind seed based activated carbon produced with 500°C activation temperature and 1.0 : 1 KOH : tamarind seed charcoal ratio was used for Fe(III) adsorption test. It was shown that Fe(III) was adsorbed in alkaline conditions and adsorption increased with increasing Fe(III) initial concentration from 5 to 20 ppm with capacity adsorption of 0.0069–0.019 mg/g. PMID:26689357

  2. Production of biodiesel fuel from canola oil with dimethyl carbonate using an active sodium methoxide catalyst prepared by crystallization.

    Science.gov (United States)

    Kai, Takami; Mak, Goon Lum; Wada, Shohei; Nakazato, Tsutomu; Takanashi, Hirokazu; Uemura, Yoshimitsu

    2014-07-01

    In this study, a novel method for the production of biodiesel under mild conditions using fine particles of sodium methoxide formed in dimethyl carbonate (DMC) is proposed. Biodiesel is generally produced from vegetable oils by the transesterification of triglycerides with methanol. However, this reaction produces glycerol as a byproduct, and raw materials are not effectively utilized. Transesterification with DMC has recently been studied because glycerol is not formed in the process. Although solid-state sodium methoxide has been reported to be inactive for this reaction, the catalytic activity dramatically increased with the preparation of fine catalyst powders by crystallization. The transesterification of canola oil with DMC was studied using this catalyst for the preparation of biodiesel. A conversion greater than 96% was obtained at 65°C for 2h with a 3:1M ratio of DMC and oil and 2.0 wt% catalyst. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Preparation of activated carbon from fly ash and its application for CO{sub 2} capture

    Energy Technology Data Exchange (ETDEWEB)

    Alhamed, Yahia Abobakor; Rather, Sami Ullah; El-Shazly, Ahmad Hasan; Zaman, Sharif Fakhruz; Daous, Mohammad Abdulrhaman; Al-Zahrani, Abdulrahim Ahmad [King Abdulaziz University, Jeddah (Saudi Arabia)

    2015-04-15

    Power and desalination plants are one of the main anthropogenic sources for CO{sub 2} generation, which is one of the key elements to cause greenhouse gas effect and thus contribute to the global warming. Fly ash (FA) generated in desalination and power plants was converted into activated carbon (AC) treated with KOH at higher temperature and tested for CO{sub 2} capturing efficiency. Morphological characteristics of FA such as BET specific surface area (SSA), pore volume, pore diameter, and pore size distribution (PSD) were performed using N{sub 2} adsorption isotherm. CO{sub 2} adsorption capacity and adsorption isotherms of CO{sub 2} over AC were measured by performing thermogravimetric analysis at different temperatures. BET SSA of 161m{sup 2}g{sup -1} and adsorption capacity of 26mg CO{sub 2}/g AC can be obtained by activation at KOH/FA ratio of 5 at 700 .deg. C and activation time of 2 h. Therefore, great potential exists for producing AC from FA, which will have the positive effect of reducing the landfill problem and global warming.

  4. A comprehensive review on removal of arsenic using activated carbon prepared from easily available waste materials.

    Science.gov (United States)

    Mondal, Monoj Kumar; Garg, Ravi

    2017-05-01

    Arsenic contamination in water bodies is a serious problem and causes various health problems due to which US Environment Protection Agency (USEPA) set its maximum permissible limit of 10 ppb. The present review article starts with the removal of toxic arsenic using adsorbents prepared from easily available waste materials. Adsorbent either commercial or low-cost adsorbent can be used for arsenic removal but recent research was focused on the low-cost adsorbent. Preparation and activation of various adsorbents were discussed. Adsorption capacities, surface area, thermodynamic, and kinetics data of various adsorbents for As(III) and As(V) removal were compiled. Desorption followed by regeneration and reuse of adsorbents is an important step in adsorption and leads to economical process. Various desorbing and regenerating agents were discussed for arsenic decontamination from the adsorbent surface. Strong acids, bases, and salts are the main desorbing agents. Disposal of arsenic-contaminated adsorbent and arsenic waste was also a big problem because of the toxic and leaching effect of arsenic. So, arsenic waste was disposed of by proper stabilization/solidification (S/S) technique by mixing it in Portland cement, iron, ash, etc. to reduce the leaching effect.

  5. Pesticides removal from waste water by activated carbon prepared from waste rubber tire.

    Science.gov (United States)

    Gupta, V K; Gupta, Bina; Rastogi, Arshi; Agarwal, Shilpi; Nayak, Arunima

    2011-07-01

    Waste rubber tire has been used for the removal of pesticides from waste water by adsorption phenomenon. By applying successive chemical and thermal treatment, a basically cabonaceous adsorbent is prepared which has not only a higher mesopore, macropore content but also has a favorable surface chemistry. Presence of oxygen functional groups as evidenced by FTIR spectra along with excellent porous and surface properties were the driving force for good adsorption efficiency observed for the studied pesticides: methoxychlor, methyl parathion and atrazine. Batch adsorption studies revealed maximum adsorption of 112.0 mg g(-1), 104.9 mg g(-1) and 88.9 mg g(-1) for methoxychlor, atrazine and methyl parathion respectively occurring at a contact time of 60 min at pH 2 from an initial pesticide concentration of 12 mg/L. These promising results were confirmed by column experiments; thereby establishing the practicality of the developed system. Effect of various operating parameters along with equilibrium, kinetic and thermodynamic studies reveal the efficacy of the adsorbent with a higher adsorption capacity than most other adsorbents. The adsorption equilibrium data obey Langmuir model and the kinetic data were well described by the pseudo-first-order model. Applicability of Bangham's equation indicates that diffusion of pesticide molecules into pores of the adsorbent mainly controls the adsorption process. Spontaneous, exothermic and random characteristics of the process are confirmed by thermodynamic studies. The developed sorbent is inexpensive in comparison to commercial carbon and has a far better efficiency for pesticide removal than most other adsorbents reported in literature. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Preparation and photocatalytic activity of multi-walled carbon nanotubes/Mg-doped ZnO nanohybrids

    Directory of Open Access Journals (Sweden)

    Chen C. S.

    2015-09-01

    Full Text Available Multi-walled carbon nanotubes/Mg-doped ZnO (MWNTs/Zn1-xMgxO nanohybrids were prepared by co-precipitation method, and their photocatalytic activity for methyl orange (MO was studied. Experimental results showed that Mg-doped ZnO nanoparticles were successfully deposited on the surface of MWNTs under annealing at 450 °C and 550 °C. The resultant MWNTs/Zn0.9Mg0.1O nanohybrids had better photocatalytic activity for degradation of methyl orange than pure ZnO: the rates of MO photodegradation were 100 % and 30 % for 1 h, respectively. The enhancement in the photocatalytic activity was attributed to the excellent electronic properties of MWNTs and Mg-doping.

  7. Adsorption of Bismark Brown dye on activated carbons prepared from rubberwood sawdust (Hevea brasiliensis) using different activation methods.

    Science.gov (United States)

    Prakash Kumar, B G; Miranda, Lima Rose; Velan, M

    2005-11-11

    Hevea brasiliensis or rubberwood tree, as it is commonly known finds limited use once the latex has been tapped. The sawdust of this tree is chosen to ascertain it viability as a precursor for activation. The carbons thus obtained were characterized in terms of iodine, methylene blue number and surface area. The best carbon in each method was utilized to study the adsorption of Bismark Brown, a dye used in the leather industry. Adsorption equilibrium studies were carried out with the synthetic solutions of the dye, at room temperature (298 K). Equilibrium data are fitted with the Langmuir and the Freundlich isotherms models for the system. The effects of contact time, adsorbent dosage and initial dye concentrations on sorption capacity were carried out. Excellent adsorption capacities of 2000 and 1111 mg g(-1) were obtained for steam and chemical followed by steam-activated carbons, respectively. Pilot-plant experimental studies have been performed using packed-bed column with different feed concentrations, flow rates and bed heights, to evaluate sorption of Bismark Brown on steam-activated carbon. Bed depth service time (BDST) design model have been used to analyze the data.

  8. Adsorption of Bismark Brown dye on activated carbons prepared from rubberwood sawdust (Hevea brasiliensis) using different activation methods

    Energy Technology Data Exchange (ETDEWEB)

    Prakash Kumar, B.G. [Department of Chemical Engineering, Alagappa College of Technology, Anna University, Chennai 600025 (India); Miranda, Lima Rose [Department of Chemical Engineering, Alagappa College of Technology, Anna University, Chennai 600025 (India); Velan, M. [Department of Chemical Engineering, Alagappa College of Technology, Anna University, Chennai 600025 (India)]. E-mail: velan@annauniv.edu

    2005-11-11

    Hevea brasiliensis or rubberwood tree, as it is commonly known finds limited use once the latex has been tapped. The sawdust of this tree is chosen to ascertain it viability as a precursor for activation. The carbons thus obtained were characterized in terms of iodine, methylene blue number and surface area. The best carbon in each method was utilized to study the adsorption of Bismark Brown, a dye used in the leather industry. Adsorption equilibrium studies were carried out with the synthetic solutions of the dye, at room temperature (298 K). Equilibrium data are fitted with the Langmuir and the Freundlich isotherms models for the system. The effects of contact time, adsorbent dosage and initial dye concentrations on sorption capacity were carried out. Excellent adsorption capacities of 2000 and 1111 mg g{sup -1} were obtained for steam and chemical followed by steam-activated carbons, respectively. Pilot-plant experimental studies have been performed using packed-bed column with different feed concentrations, flow rates and bed heights, to evaluate sorption of Bismark Brown on steam-activated carbon. Bed depth service time (BDST) design model have been used to analyze the data.

  9. Preparation of iron-impregnated granular activated carbon for arsenic removal from drinking water.

    Science.gov (United States)

    Chang, Qigang; Lin, Wei; Ying, Wei-chi

    2010-12-15

    Granular activated carbon (GAC) was impregnated with iron through a new multi-step procedure using ferrous chloride as the precursor for removing arsenic from drinking water. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) analysis demonstrated that the impregnated iron was distributed evenly on the internal surface of the GAC. Impregnated iron formed nano-size particles, and existed in both crystalline (akaganeite) and amorphous iron forms. Iron-impregnated GACs (Fe-GACs) were treated with sodium hydroxide to stabilize iron in GAC and impregnated iron was found very stable at the common pH range in water treatments. Synthetic arsenate-contaminated drinking water was used in isotherm tests to evaluate arsenic adsorption capacities and iron use efficiencies of Fe-GACs with iron contents ranging from 1.64% to 12.13% (by weight). Nonlinear regression was used to obtain unbiased estimates of Langmuir model parameters. The arsenic adsorption capacity of Fe-GAC increased significantly with impregnated iron up to 4.22% and then decreased with more impregnated iron. Fe-GACs synthesized in this study exhibited higher affinity for arsenate as compared with references in literature and shows great potential for real implementations. Copyright © 2010 Elsevier B.V. All rights reserved.

  10. Effective removal of tetracycline from aqueous solution using activated carbon prepared from tomato (Lycopersicon esculentum Mill.) industrial processing waste.

    Science.gov (United States)

    Sayğılı, Hasan; Güzel, Fuat

    2016-09-01

    Activated carbon (TAC) prepared under optimized conditions with ZnCl2 activation from a new precursor; tomato industrial processing waste (TW), was applied as an adsorbent to remove tetracycline (TC) from aqueous solution. The factors (TAC dosage, initial TC concentration, contact time, ionic strength and solution temperature) affecting the adsorption process were examined at natural pH (5.7) of TAC-TC system in aqueous solution. Kinetic data was found to be best complied by the pseudo-second order model. The isotherm analysis indicated that the equilibrium data could be represented by the Langmuir model. The maximum adsorption capacity was identified as 500.0mgg(-1) at 308K. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. An efficient visible-light photocatalyst prepared by modifying AgBr particles with a small amount of activated carbon

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Desong, E-mail: dswang06@126.com; Zhao, Mangmang; Luo, Qingzhi; Yin, Rong; An, Jing; Li, Xueyan

    2016-04-15

    Highlights: • An efficient visible-light photocatalyst was prepared by modifying AgBr particles. • A small amount of activated carbon was used to modify AgBr particles. • The modified AgBr exhibited improved visible-light photocatalytic performances. - Abstract: An efficient visible-light photocatalyst was successfully prepared by modifying AgBr particles with a small amount of activated carbon (AC) via a simple chemical precipitation approach. The AC/AgBr composite was characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, UV–vis diffuse reflection spectroscopy, photoluminescence spectroscopy, electrochemical impedance spectroscopy. The photocatalytic performances of the AC/AgBr composite were investigated by evaluating photodegradation of methyl orange (MO) and phenol under visible light irradiation, and the effects of the AC content in the composite, concentrations of AC/AgBr composite and MO, carrier scavengers on MO photodegradation rate were systematically investigated. The results indicated that the modification of AC can hardly change the crystalline and crystal size of AgBr particles, while significantly improve their specific surface areas, visible-light absorption and separation efficiency of photogenerated electron–hole pairs. Compared with pure AgBr, the AC/AgBr composite exhibited drastically enhanced visible-light photocatalytic activity and stability. The photogenerated electrons and holes, hydroxyl radicals are responsible to the photodegradation of organic pollutants, and the photogenerated holes are the main active species. On the basis of the results and the properties of AC and AgBr, the visible-light photocatalytic mechanism of the AC/AgBr composite was discussed.

  12. Toward new benchmark adsorbents: preparation and characterization of activated carbon from argan nut shell for bisphenol A removal.

    Science.gov (United States)

    Zbair, Mohamed; Ainassaari, Kaisu; Drif, Asmaa; Ojala, Satu; Bottlinger, Michael; Pirilä, Minna; Keiski, Riitta L; Bensitel, Mohammed; Brahmi, Rachid

    2018-01-01

    The use of argan nut shell as a precursor for producing activated carbon was investigated in this work. Two activated carbons AC-HP and AC-Na were prepared from argan nut shell by chemical activation method using phosphoric acid (H3PO4) and sodium hydroxide (NaOH), respectively. Textural, morphological, and surface chemistry characteristics were studied by nitrogen physisorption, TGA, SEM, TXRF, FTIR, XRD, and by determining the pHPZC of the AC-HP. The adsorption experiments revealed that AC-HP was more efficient in adsorption of BPA due to high specific surface area (1372 m2/g) compared to AC-Na (798 m2/g). The obtained adsorption data of BPA on AC-HP correlated well with the pseudo-second-order model and the Langmuir isotherm (Qmax = 1250 mg/g at 293 K). The thermodynamic parameters (ΔG° < 0, ΔH° < 0, and ΔS° < 0) indicate that adsorption of BPA on AC-HP was spontaneous and exothermic in nature. The regeneration of AC-HP showed excellent results after 5 cycles (95-93%). This work does not only provide a potential way to use argan nut shell but also represents a sustainable approach to synthesize AC-HP, which might be an ideal material for various applications (energy storage, catalysis, and environmental remediation).

  13. Catalytic activity vs. size correlation in platinum catalysts of PEM fuel cells prepared on carbon black by different methods

    Energy Technology Data Exchange (ETDEWEB)

    Nores-Pondal, F.J.; Granada, M.; Corti, H.R. [Departamento de Fisica de la Materia Condensada, Centro Atomico Constituyentes, Comision Nacional de Energia Atomica (CNEA), General Paz 1499, 1650 San Martin, Buenos Aires (Argentina); Vilella, I.M.J.; de Miguel, S.R.; Scelza, O.A. [Instituto de Investigaciones en Catalisis y Petroquimica (INCAPE), Facultad de Ingenieria Quimica (Universidad Nacional del Litoral) - CONICET, Santiago del Estero 2654, 3000 Santa Fe (Argentina); Troiani, H. [Departamento de Fisica, Centro Atomico Bariloche, Comision Nacional de Energia Atomica (CNEA), Av. Bustillo 9500, 8400 San Carlos de Bariloche (Argentina)

    2009-10-15

    In this work nanoparticulated platinum catalysts have been prepared on carbon Vulcan XC-72 using three methods starting with chloroplatinic acid as a precursor: (i) formic acid as a reductor agent; (ii) impregnation method followed by reduction in hydrogen atmosphere at moderated temperature; and (iii) microwave-assisted reduction in ethylene glycol. The catalytic and size studies were also performed on a commercial Pt catalyst (E-Tek, De Nora). The characterization of the particle size and distribution was performed by means of transmission electron microscopy (TEM) and X-ray diffraction (XRD). The characterizations of the catalytic and electrocatalytic properties of the catalysts were determined by studying the cyclohexane dehydrogenation reaction (CHD) and the behavior under cyclic voltammetry (CV) in sulfuric acid solutions. The measured electrochemical activity, along with the hydrogen chemisorption of the catalysts allows the estimation of effective particle sizes, which are much larger than those measured by TEM and XRD. The catalysts prepared by reduction with formic acid and ethylene glycol (microwave-assisted) show electrochemical activities very close to those of the commercial catalyst, and are almost insensitive to the Pt dispersion or Pt particle size. The chemical activity in CHD correlates well with the metallic dispersion determined by hydrogen chemisorption, indicating similar accesibility of H{sub 2} and cyclohexane to the catalyst surface. (author)

  14. A facile route for preparation of magnetic biomass activated carbon with high performance for removal of dye pollutants.

    Science.gov (United States)

    Luo, Hao; Zhang, Shengxiao; Li, Xiaoyan; Xu, Qiang; Liu, Junshen; Wang, Zhenhua

    2017-06-01

    A novel and simple method for preparing magnetic biomass activated carbon (BAC) was developed. The BAC was prepared by decomposing fallen leaves, and magnetic nanoparticles were grown in situ on BAC using solvothermal method. The prepared magnetic BAC was characterized with FT-IR, XRD, vibrating sample magnetometer, thermo-gravimetric apparatus, SEM, and high-resolution transmission electron microscope, and results indicate that BAC and magnetic nanoparticles were combined together successfully. To investigate the adsorption ability of the composites, several dyes were selected as sample pollutants, and the sorbent showed high adsorption capacity for the dyes. The solution pH had no significant effect on the adsorption in the range of 5-9. The adsorption behavior of magnetic BAC for dyes followed the Langmuir isotherm model, and the adsorption capacity of congo red, neutral red, and methyl green were 396.8, 171.2, and 403.2 mg/g, respectively. The maximum adsorption capacity in natural water showed no obvious decrease, indicating the strong anti-interference ability of the sorbents. The Gibbs free energy calculated from the thermodynamics data was negative, demonstrating that the adsorption of these dyes on the magnetic BAC was spontaneous. The magnetic BAC showed a great potential for the removal of dye pollutants from environment water.

  15. Batch and fixed-bed adsorption of tartrazine azo-dye onto activated carbon prepared from apricot stones

    Science.gov (United States)

    Albroomi, H. I.; Elsayed, M. A.; Baraka, A.; Abdelmaged, M. A.

    2017-07-01

    This work describes the potential of utilizing prepared activated carbon from apricot stones as an efficient adsorbent material for tartrazine (TZ) azo-dye removal in a batch and dynamic adsorption system. The results revealed that activated carbons with well-developed surface area (774 m2/g) and pore volume (1.26 cm3/g) can be manufactured from apricot stones by H3PO4 activation. In batch experiments, effects of the parameters such as initial dye concentration and temperature on the removal of the dye were studied. Equilibrium was achieved in 120 min. Adsorption capacity was found to be dependent on the initial concentration of dye solution, and maximum adsorption was found to be 76 mg/g at 100 mg/L of TZ. The adsorption capacity at equilibrium ( q e) increased from 22.6 to 76 mg/g with an increase in the initial dye concentrations from 25 to 100 mg/L. The thermodynamic parameters such as change in free energy (Δ G 0), enthalpy (Δ H 0) and entropy (Δ S 0) were determined and the positive value of (Δ H) 78.1 (K J mol-1) revealed that adsorption efficiency increased with an increase in the process temperature. In fixed-bed column experiments, the effect of selected operating parameters such as bed depth, flow rate and initial dye concentration on the adsorption capacity was evaluated. Increase in bed height of adsorption columns leads to an extension of breakthrough point as well as the exhaustion time of adsorbent. However, the maximum adsorption capacities decrease with increases of flow rate. The breakthrough data fitted well to bed depth service time and Thomas models with high coefficient of determination, R 2 ≥ 94.

  16. Preparation of ultrafine magnetic biochar and activated carbon for pharmaceutical adsorption and subsequent degradation by ball milling

    Science.gov (United States)

    Shan, Danna; Deng, Shubo; Zhao, Tianning; Wang, Bin; Wang, Yujue; Huang, Jun; Yu, Gang; Winglee, Judy; Wiesner, Mark R.

    2017-01-01

    Ball milling was used to prepare two ultrafine magnetic biochar/Fe3O4 and activated carbon (AC)/Fe3O4 hybrid materials targeted for use in pharmaceutical removal by adsorption and mechanochemical degradation of pharmaceutical compounds. Both hybrid adsorbents prepared after 2 hours milling exhibited high removal of carbamazepine (CBZ), and were easily separated magnetically. These adsorbents exhibited fast adsorption of CBZ and tetracycline (TC) in the initial 1 hour. The biochar/Fe3O4 had a maximum adsorption capacity of 62.7 mg/g for CBZ and 94.2 mg/g for TC, while values obtained for AC/Fe3O4 were 135.1 mg/g for CBZ and 45.3 mg/g for TC respectively when data were fitted using the Langmuir expression. Solution pH values slightly affected the sorption of TC on the adsorbents, while CBZ sorption was almost pH-independent. The spent adsorbents with adsorbed CBZ and TC were milled to degrade the adsorbed pollutants. The adsorbed TC itself was over 97% degraded after 3 hours of milling, while about half of adsorbed CBZ were remained. The addition of quartz sand was found to improve the mechanochemical degradation of CBZ on biochar/Fe3O4, and its degradation percent was up to 98.4% at the dose of 0.3 g quarts sand/g adsorbent. This research provided an easy method to prepare ultrafine magnetic adsorbents for the effective removal of typical pharmaceuticals from water or wastewater and degrade them using ball milling. PMID:26685062

  17. Silver nanoparticles-loaded activated carbon fibers using chitosan as binding agent: Preparation, mechanism, and their antibacterial activity

    Science.gov (United States)

    Tang, Chengli; Hu, Dongmei; Cao, Qianqian; Yan, Wei; Xing, Bo

    2017-02-01

    The effective and strong adherence of silver nanoparticles (AgNPs) to the substrate surface is pivotal to the practical application of those AgNPs-modified materials. In this work, AgNPs were synthesized through a green and facile hydrothermal method. Chitosan was introduced as the binding agent for the effective loading of AgNPs on activated carbon fibers (ACF) surface to fabricate the antibacterial material. Apart from conventional instrumental characterizations, i. e., scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), zeta potential and Brunauer-Emmett-Teller (BET) surface area measurement, molecular dynamics simulation method was also applied to explore the loading mechanism of AgNPs on the ACF surface. The AgNPs-loaded ACF material showed outstanding antibacterial activity for S. aureus and E. coli. The combination of experimental and theoretical calculation results proved chitosan to be a promising binding agent for the fabrication of AgNPs-loaded ACF material with excellent antibacterial activity.

  18. Silver nanoparticles-loaded activated carbon fibers using chitosan as binding agent: Preparation, mechanism, and their antibacterial activity

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Chengli, E-mail: tcl-lily@mail.zjxu.edu.cn [College of Mechanical and Electrical Engineering, Jiaxing University, Jiaxing 314001 (China); Hu, Dongmei [College of Mechanical Science and Engineering, Jilin University, Changchun 130022 (China); Cao, Qianqian [College of Mechanical and Electrical Engineering, Jiaxing University, Jiaxing 314001 (China); Yan, Wei [Department of Environmental Science and Engineering, Xi’an Jiaotong University, Xi’an 710049 (China); Xing, Bo [College of Mechanical and Electrical Engineering, Jiaxing University, Jiaxing 314001 (China)

    2017-02-01

    Highlights: • Chitosan was firstly introduced as binding agent for AgNPs loading on ACF surface. • Molecular dynamics simulation was used to explore the AgNPs loading mechanism. • Loading mechanism was proposed based on the experimental and simulation results. • Antibacterial AgNPs-loaded ACF showed use potential for water disinfection. - Abstract: The effective and strong adherence of silver nanoparticles (AgNPs) to the substrate surface is pivotal to the practical application of those AgNPs-modified materials. In this work, AgNPs were synthesized through a green and facile hydrothermal method. Chitosan was introduced as the binding agent for the effective loading of AgNPs on activated carbon fibers (ACF) surface to fabricate the antibacterial material. Apart from conventional instrumental characterizations, i. e., scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), zeta potential and Brunauer-Emmett-Teller (BET) surface area measurement, molecular dynamics simulation method was also applied to explore the loading mechanism of AgNPs on the ACF surface. The AgNPs-loaded ACF material showed outstanding antibacterial activity for S. aureus and E. coli. The combination of experimental and theoretical calculation results proved chitosan to be a promising binding agent for the fabrication of AgNPs-loaded ACF material with excellent antibacterial activity.

  19. Rapid Removal of Zinc(II) from Aqueous Solutions Using a Mesoporous Activated Carbon Prepared from Agricultural Waste.

    Science.gov (United States)

    Zhang, Xiaotao; Hao, Yinan; Wang, Ximing; Chen, Zhangjing

    2017-08-28

    A low-cost activated carbon (XSBLAC) prepared from XanthocerasSorbifoliaBungehull via chemical activation was investigated to determine its adsorption and desorption properties for zinc(II) ions from aqueous solutions. XSBLAC was characterized based on its N₂-adsorption/desorption isotherm, EDX, XRD, SEM and FTIR results. An adsorption study was conducted in a series of experiments to optimize the process variables for zinc(II) removal using XSBLAC. Modeling the adsorption kinetics indicated good agreement between the experimental data and the pseudo-second-order kinetic model. The Langmuir equilibrium isotherm fit the experimental data reasonably well. The calculated enthalpy (ΔH⁰), entropy (ΔS⁰) and Gibbs free energy (ΔG⁰) values revealed the endothermic and spontaneous nature of the adsorption process. HNO₃ displayed the best desorption performance. The adsorption mechanism was investigated in detail through FTIR and SEM/EDX spectroscopic analyses. The results suggested that XSBLAC is a potential biosorbent for removing zinc(II) from aqueous solutions.

  20. Characterization and use of high surface area activated carbons prepared from cane pith for liquid-phase adsorption

    Energy Technology Data Exchange (ETDEWEB)

    Tseng, R.-L. [Graduate Institute of Environmental Engineering, National Taiwan University, Taiwan (China) and Department of Safety, Health and Environmental Engineering, National United University, Miao-Li 360, Taiwan (China)]. E-mail: trl@nuu.edu.tw; Tseng, S.-K. [Graduate Institute of Environmental Engineering, National Taiwan University, Taiwan (China)

    2006-08-25

    Carbonaceous adsorbents with controllable surface areas were chemically activated with KOH at 780 deg. C from char that had been carbonized from cane pith at 450 deg. C. The pore properties including the BET surface area, pore volume, pore size distribution, and mean pore diameter of these activated carbons were characterized and derived using the t-plot method based on N{sub 2} adsorption isotherms. The activated cane pith carbons, with KOH/char ratios of 2-6, exhibited BET surface areas ranging from 912 to 2299 m{sup 2} g{sup -1}. The scanning electron microscopic (SEM) observations revealed that the surface morphology of honeycombed holes on all activated cane pith carbons was significantly influenced by the KOH/char ratio. The adsorption kinetics and equilibrium isotherms of acid blue 74, methylene blue, basic brown 1, p-nitrophenol, p-chlorophenol, p-cresol, and phenol from water at 30 deg. C on the activated carbons were studied. The adsorption kinetics were suitably described by a simplified kinetic model, the Elovich equation. All adsorption equilibrium isotherms were in agreement with the Langmuir equation, and were used to compare the covered area (S {sub c}/S {sub p}) of the activated carbons at different KOH/char ratios. The high-surface-area activated carbons were proven to be promising adsorbents for pollution control and for other applications.

  1. Effect of the preparation conditions on the catalytic activity of calcined Ca/Al-layered double hydroxides for the synthesis of glycerol carbonate

    OpenAIRE

    Salagre, P.; Granados-Reyes, J.; Cesteros, Y.

    2017-01-01

    Effect of the preparation conditions on the catalytic activity of calcined Ca/Al-layered double hydroxides for the synthesis of glycerol carbonate DOI: 10.1016/j.apcata.2017.02.013 URL: http://www.sciencedirect.com/science/article/pii/S0926860X17300686 Filiació URV: SI Memòria The effect of the preparation conditions of several calcined Ca/Al layered double hydroxide compounds (CaAl-LDH) on the catalytic transesterification of glycerol with dimethyl carbonate to obtain glycerol...

  2. Preparation and characterization of activated carbon from the char produced in the thermolysis of granulated scrap tyres.

    Science.gov (United States)

    López, F A; Centeno, T A; Rodríguez, O; Alguacil, E J

    2013-05-01

    The char produced in the thermolysis of granulated scrap tyres has few market outlets, reducing the economic viability of the thermolytic process. This paper reports the potential of this char as a low-cost precursor of porous carbons. The tyre-derived char was demineralized in either alkaline or acidic media to reduce its ash, zinc, sulfur, and silica contents. The lowest impurity content was achieved with an HNO3/H2O treatment. The resulting demineralized char was then subjected to activation by KOH or CO2. The Brunauer-Emmett-Teller (BET)-specific surface area of the activated carbon produced by the KOH treatment was 242 m2/g, whereas that of the CO2-activated carbon was 720 m2/g. The textural properties of the latter product were similar to those of some commercial activated carbons. The use of tyre-derived char as a precursor of porous carbons could render the thermolytic treatment of scrap tyres more economically attractive. Char produced in thermolysis of granulated scrap tyres has a few market outlets; in this paper an alternative for its use is presented. The char was converted into activated carbon with textural properties similar to those of some commercial activated carbons. This process could render the thermolytic treatment of scrap tyres more economically attractive.

  3. Particle size distribution and morphological changes in activated carbon-metal oxide hybrid catalysts prepared under different heating conditions.

    Science.gov (United States)

    Barroso-Bogeat, A; Alexandre-Franco, M; Fernández-González, C; Gómez-Serrano, V

    2016-03-01

    In catalysis processes, activated carbon (AC) and metal oxides (MOs) are widely used either as catalysts or as catalyst supports because of their unique properties. A combination of AC and a MO in a single hybrid material entails changes not only in the composition, microstructure and texture but also in the morphology, which may largely influence the catalytic behaviour of the resulting product. This work is aimed at investigating the modifications in the morphology and particle size distribution (PSD) for AC-MO hybrid catalysts as a result of their preparation under markedly different heating conditions. From a commercial AC and six MO (Al2O3, Fe2O3, ZnO, SnO2, TiO2 and WO3) precursors, two series of such catalysts are prepared by wet impregnation, oven-drying at 120 ºC, and subsequent heat treatment at 200 ºC or 850 ºC in inert atmosphere. The resulting samples are characterized in terms of their morphology and PSD by scanning electron microscopy and ImageJ processing program. Obtained results indicate that the morphology, PSD and degree of dispersion of the supported catalysts are strongly dependent both on the MO precursor and the heat treatment temperature. With the temperature rise, trends are towards the improvement of crystallinity, the broadening of the PSD and the increase in the average particle size, thus suggesting the involvement of sintering mechanisms. Such effects are more pronounced for the Fe, Sn and W catalysts due to the reduction of the corresponding MOs by AC during the heat treatment at 850 ºC. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.

  4. Equilibrium, kinetic and thermodynamic studies on the adsorption of 2-nitroaniline onto activated carbon prepared from cotton stalk fibre

    Energy Technology Data Exchange (ETDEWEB)

    Li Kunquan [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China); Nanjing Agricultural University, Nanjing 210031 (China); Zheng Zheng, E-mail: zzheng@nju.edu.cn [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China); Huang Xingfa; Zhao Guohua; Feng Jingwei; Zhang Jibiao [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China)

    2009-07-15

    Activated carbon prepared from cotton stalk fibre has been utilized as an adsorbent for the removal of 2-nitroaniline from aqueous solutions. The influence of adsorbent mass, contact time and temperature on the adsorption was investigated by conducting a series of batch adsorption experiments. The equilibrium data at different temperatures were fitted with the Langmuir, Freundlich, Tempkin, Redlich-Peterson and Langmuir-Freundlich models. The Langmuir-Freundlich isotherm was found to best describe the experimental data. The adsorption amount increased with increasing temperature. The maximum adsorption capacity of 2-nitroaniline was found to be 383 mg/g for initial 2-nitroaniline concentration of 200 mg/L at 45 {sup o}C. The kinetic rates were modeled by using the Lagergren-first-order, pseudo-second-order and Elovich models. The pseudo-second-order model was found to explain the adsorption kinetics most effectively. It was also found that the pore diffusion played an important role in the adsorption, and intraparticle diffusion was the rate-limiting step at the first 30 min for the temperatures of 25, 35 and 45 {sup o}C. FTIR and {sup 13}C NMR study revealed that the amino and isocyanate groups present on the surface of the adsorbent were involved in chemical interaction with 2-nitroaniline. The negative change in free energy ({Delta}G{sup o}) and positive change in enthalpy ({Delta}H{sup o}) indicated that the adsorption was a spontaneous and endothermic process.

  5. Preparation and Utilization of Corncob Activated Carbon for Dyes Removal from Aqueous Solutions: Batch and Continuous Study

    Directory of Open Access Journals (Sweden)

    Mohammad Abd Muslim AL- Tufaily

    2016-09-01

    Full Text Available Commercial activated carbon and produced corncob activated carbon were used for the adsorption of methylene blue dye from aqueous solution using batch and continuous processes. Batch processes were conducted to study the effects of solution pH, contact time, adsorbent dose, agitation speed and initial dye concentration. The optimum values for methylene blue dye adsorption were: solution pHs of 6 and 7, contact times of 8 and 5 hr., adsorbent dosages of 1.5, and 0.5 gm, agitation speeds of 200 and 250 rpm and initial dye concentration of 50 mg/l calculated by commercial activated carbon and corncob activated carbon respectively. Two isotherm models, Freundlich and Langmuir fitted with the experimental data found from batch processes, the Langmuir model fitted well than the Freundlich, with maximum adsorption capacities of 16.21 and 30.95 mg/g and R2 of 0.952 and 0.992 predicted by commercial activated carbon and corncob activated carbon respectively. Radial and vertical flow regime reactors were conducted in column tests for the two adsorbent materials at different three flow rates (0.2, 0.3 and 0.4 L/min and initial dye concentrations 15 mg/l, the same volume of (775 ml from adsorbent materials used for both radial and vertical reactors to make a comparison between the capacity of the adsorbent materials each with another and between the performance of radial and vertical flow regime reactors configurations on breakthrough curves behavior. Radial flow regime reactor showed good results in comparison with vertical flow regime reactor.

  6. production and characterization of activated carbon from leather ...

    African Journals Online (AJOL)

    dell

    ABSTRACT. Powdered activated carbon (PAC) was prepared from leather buffing waste, sawdust and lignite by carbonization ... Key words: Activated carbon, carbonization, Steam activation, Adsorption efficiency, Leather buffing waste. INTRODUCTION ..... Distribution Measurement” Separation Science and Technology 28 ...

  7. Evaluation of dynamics and equilibrium models for the sorption of Basic Violet 3 on activated carbon prepared from Moringa Oleifera fruit shell waste

    Directory of Open Access Journals (Sweden)

    C. Sumithra

    2014-03-01

    Full Text Available The feasibility of activated carbon prepared from Moringa oleifera fruit shell waste to remove Basic Violet 3 from aqueous solution was investigated through batch mode contact time studies. The surface chemistry of activated carbon is studied using Boehm titrations and pH of PZC measurements indicates that the surface oxygenated groups are mainly basic in nature. The surface area of the activated carbon is determined using BET method. The kinetics of Basic Violet 3 adsorption are observed to be pH dependent. The experimental data can be explained by Pseudo second order kinetic model. For, Basic Violet 3, the Langmuir model is best suited to stimulate the adsorption isotherms.

  8. Study on preparation of water hyacinth-based activated carbon for pulp and paper mill wastewater treatment.

    Science.gov (United States)

    Boonpoke, Anusorn

    2015-09-01

    Mulberry pulp and paper mills produce high chemical- and organic matter containing waste water in Thailand. Many of the mills are not equipped with wastewater treatment unit; their untreated effluent is directly discharged into recipient water resources. The effluent constituents are well recognized as acute and chronic pollutants that are hazardous to the environment. The present study aimed to investigate the utilization of an activated carbon from a low-cost material and to examine its adsorption performance using batch and fixed-bed adsorption. Water hyacinth was used as a raw material for activated carbon production via a chemical activation method. The results showed that water hyacinth-based activated carbon (WHAC) provided a high surface area of 912-1,066 m2g(-1) and exhibited micropore structure. Based on the Freundlich fit, the maximum adsorption capacity of COD and color was 4.52 mgg(-1) and 13.57 Pt-Cog(-1), respectively. The fixed bed adsorption provided maximum removal efficiency of 91.70 and 92.62% for COD and color, respectively. A continuous adsorption data agreed well with the Thomas kinetic model. In summary, water hyacinth can be used as a low-cost material for activated carbon production with high removal efficiency of COD and color for pulp and paper mill wastewater treatment.

  9. Preparation and textural characterisation of activated carbon from vine shoots ( Vitis vinifera) by H 3PO 4—Chemical activation

    Science.gov (United States)

    Corcho-Corral, B.; Olivares-Marín, M.; Fernández-González, C.; Gómez-Serrano, V.; Macías-García, A.

    2006-06-01

    An abundant and low-cost agricultural waste as vine shoots ( Vitis vinifera) (VS), which is generated by the annual pruning of vineyards, has been used as raw material in the preparation of powder activated carbon (AC) by the method of chemical activation with phosphoric acid. After size reduction, VS were impregnated for 2 h with 60 wt.% H 3PO 4 solution at room temperature, 50 and 85 °C. The three impregnated products were carbonised at 400 °C. The product impregnated at 50 °C was heated either first at 150-250 °C and then at 400 °C or simply at 350-550 °C in N 2 atmosphere. The time of isothermal treatment after each dynamic heating was 2 h. The carbons were texturally characterised by gas adsorption (N 2, -196 °C), mercury porosimetry, and density measurements. FT-IR spectroscopy was also applied. Better developments of surface area and microporosity are obtained when the impregnation of VS with the H 3PO 4 solution is effected at 50 °C and for the products heated isothermally at 200 and 450 °C. The mesopore volume is also usually higher for the products impregnated and heated at intermediate temperatures.

  10. Mesoporous-activated carbon prepared from chitosan flakes via single-step sodium hydroxide activation for the adsorption of methylene blue.

    Science.gov (United States)

    Marrakchi, F; Ahmed, M J; Khanday, W A; Asif, M; Hameed, B H

    2017-05-01

    In this work, mesoporous-activated carbon (CSAC) was prepared from chitosan flakes (CS) via single-step sodium hydroxide activation for the adsorption of methylene blue (MB). CSAC was prepared using different impregnation ratios of NaOH:CS (1:1, 2:1, 3:1, and 4:1) at 800°C for 90min. The adsorption performance of CSAC was evaluated for MB at different adsorption variables, such MB initial concentrations (25-400mg/L), solution pH (3-11), and temperature (30-50°C). The adsorption isotherm data of CSAC-MB were well fitted to Langmuir model with a maximum adsorption capacity 143.53mg/g at 50°C. Best representation of kinetic data was obtained by the pseudo-second order model. CSAC exhibited excellent adsorption uptake for MB and can potentially be used for other cationic dyes. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Preparation of nitrogen-doped graphene/activated carbon composite papers to enhance energy storage in supercapacitors

    Science.gov (United States)

    Li, Yong-feng; Liu, Yan-zhen; Liang, Yu; Guo, Xiao-hui; Chen, Cheng-meng

    2017-09-01

    This report presents a facile and effective method to synthesize freestanding nitrogen-doped reduced graphene oxide (rGO)/activated carbon (AC) composite papers for supercapacitors by a method combining vacuum filtration with post-annealing in NH3 atmosphere. The effect of activated carbon contents on the microstructure and capacitive behavior of the resulting composite papers before and after the annealing was investigated by X-ray diffraction, scanning electron microscopy, and Raman and X-ray photoelectron spectroscopy. Results show that the composite paper with a 30% activated carbon loading has a high nitrogen content of 14.6 at% and superior capacitive performance (308 F/g, 1 A/g) to the other composite papers with various activated carbon loadings. Nitrogen was doped and GO reduced during the annealing. The rGO nanosheets acted as a framework, and the AC particles served as spacers to avoid agglomeration of graphene sheets. The high capacitance of the composite paper is ascribed to the electric double-layer behavior and the reversible redox reactions of the nitrogen and oxygen groups. The entire process is simple, environmental friendly and easily scalable for mass production.

  12. Preparation of Co-Mo catalyst using activated carbon produced from egg shell and SiO2 as support – A hydrogenation study

    Directory of Open Access Journals (Sweden)

    Adeniyi Sunday Ogunlaja

    2010-12-01

    Full Text Available The preparation of a series of cobalt-molybdenum (Co-Mo catalysts supported on SiO2 and carbonized egg shells were investigated using standard procedures; the catalysts were further calcined at the 500 oC temperature to generate the internally consistent set, and the metal atoms content were varied in a regular manner. The ratio 1:4 (Co2+: Mo6+ by weight was employed for the various catalysts prepared. The carbonized egg shells were divided into two parts: the first part was leached with HNO3, as the other one was not leached. Activity tests were run using these catalysts containing leached and unleached carbon for the hydrogenation of methyl orange; the changes in absorbance regarding the unhydrogenated methyl orange at a wavelength of 460 nm were respectively 0.07 and 0.067 when the catalyst containing the leached carbonized egg shell (catalyst A and the catalyst containing the unleached activated carbon (catalyst B were used for the hydrogenation reaction. This confirms that catalyst A is more efficient in hydrogenating methyl orange than catalyst B.

  13. Preparation of different carbon materials by thermochemical conversion of Lignin

    Directory of Open Access Journals (Sweden)

    Juana Maria Rosas

    2014-12-01

    Full Text Available Lignin valorization plays a crucial role within the modern biorefinery scheme from both the economic and environmental points of view; and the structure and composition of lignin becomes it an ideal precursor for the preparation of advanced carbon materials with high added-value. This review provides an overview of the different carbonaceous materials obtained by thermochemical conversion of lignin, such as activated carbons, carbon fibers, template carbons; high ordered carbons; giving information about the new strategies in terms of the preparation method and their possible applications.

  14. Preparation of different carbon materials by thermochemical conversion of Lignin

    Science.gov (United States)

    Rosas, Juana; Berenguer, Raul; Valero-Romero, Maria; Rodriguez-Mirasol, Jose; Cordero, Tomás

    2014-12-01

    Lignin valorization plays a crucial role within the modern biorefinery scheme from both the economic and environmental points of view; and the structure and composition of lignin becomes it an ideal precursor for the preparation of advanced carbon materials with high added-value. This review provides an overview of the different carbonaceous materials obtained by thermochemical conversion of lignin, such as activated carbons, carbon fibers, template carbons; high ordered carbons; giving information about the new strategies in terms of the preparation method and their possible applications.

  15. Optimization of Preparation of Activated Carbon from Ricinus communis Leaves by Microwave-Assisted Zinc Chloride Chemical Activation: Competitive Adsorption of Ni2+ Ions from Aqueous Solution

    Directory of Open Access Journals (Sweden)

    M. Makeswari

    2013-01-01

    Full Text Available The preparation of activated carbon (AC from Ricinus communis leaves was investigated in this paper. Orthogonal array experimental design method was used to optimize the preparation of AC using microwave assisted zinc chloride. Optimized parameters were radiation power of 100 W, radiation time of 8 min, concentration of zinc chloride of 30% by volume, and impregnation time of 24 h, respectively. The surface characteristics of the AC prepared under optimized conditions were examined by pHZPC, SEM-EDAX, XRD, and FTIR. Competitive adsorption of Ni2+ ions on Ricinus communis leaves by microwave assisted zinc chloride chemical activation (ZLRC present in binary and ternary mixture was compared with the single metal solution. The effects of the presence of one metal ion on the adsorption of the other metal ion were investigated. The experimental results indicated that the uptake capacity of one metal ion was reduced by the presence of the other metal ion. The extent of adsorption capacity of the binary and ternary metal ions tested on ZLRC was low (48–69% as compared to single metal ions. Comparisons with the biosorption of Ni2+ ions by the biomass of ZLRC in the binary (48.98–68.41%-~Ni-Cu and 69.76–66.29%-~Ni-Cr and ternary solution (67.32–57.07%-~Ni–Cu and Cr could lead to the conclusion that biosorption of Ni2+ ions was reduced by the influence of Cu2+ and Cr3+ ions. The equilibrium data of the adsorption was well fitted to the Langmuir isotherm. The adsorption process follows the pseudo-second-order kinetic model.

  16. Kinetic, equilibrium and thermodynamic studies of synthetic dye removal using pomegranate peel activated carbon prepared by microwave-induced KOH activation

    Directory of Open Access Journals (Sweden)

    Mohd Azmier Ahmad

    2014-08-01

    Full Text Available Pomegranate peel was converted into activated carbon using microwave induced and KOH activation techniques. The prepared activated carbon (PPAC was characterized using FTIR, TGA, SEM, and nitrogen-adsorption surface area (BET. BET measurements gave remarkable increase in both the surface area (941.02 m2/g and total pore volume (0.470 cm3/g. Various operational parameters such as pH, initial dye concentration, contact time and solution temperature in batch systems were investigated on the use of PPAC in the adsorption of remazol brilliant blue reactive (RBBR dye. At pH 2, the optimum dye removal was 94.36%. The amount of dye removed was dependent on initial dye concentration and solution temperature. Adsorption kinetics was found to follow pseudo-second-order kinetic model. Experimental data were analyzed using eight model equations: Langmuir, Freundlich, Temkin, Dubinin–Radushkevich, Radke Prausnite, Sips, Viet–Sladek and Brouers – Sotolongo isotherms and it was found that the Freundlich isotherm model fitted the adsorption data most with the highest correlation (R2≥0.99 and lowest normalized standard deviation, ∆qe. Both intra-particle and film diffusion governed the adsorption process. Thermodynamic parameters, such as standard Gibbs free energy (∆G0, standard enthalpy (∆H0, standard entropy (∆S0, and the activation energy (Ea were calculated. The adsorption of RBBR dye onto PPAC was found to be spontaneous and exothermic in nature. This study shows that the adsorption follows physisorption mechanism.

  17. TiO2 Immobilized on Manihot Carbon: Optimal Preparation and Evaluation of Its Activity in the Decomposition of Indigo Carmine

    Directory of Open Access Journals (Sweden)

    Cynthia M. Antonio-Cisneros

    2015-01-01

    Full Text Available Applications of carbon-TiO2 materials have attracted attention in nanotechnology due to their synergic effects. We report the immobilization of TiO2 on carbon prepared from residues of the plant Manihot, commercial TiO2 and glycerol. The objective was to obtain a moderate loading of the anatase phase by preserving the carbonaceous external surface and micropores of the composite. Two preparation methods were compared, including mixing dry precursors and immobilization using a glycerol slurry. The evaluation of the micropore blocking was performed using nitrogen adsorption isotherms. The results indicated that it was possible to use Manihot residues and glycerol to prepare an anatase-containing material with a basic surface and a significant SBET value. The activities of the prepared materials were tested in a decomposition assay of indigo carmine. The TiO2/carbon eliminated nearly 100% of the dye under UV irradiation using the optimal conditions found by a Taguchi L4 orthogonal array considering the specific surface, temperature and initial concentration. The reaction was monitored by UV-Vis spectrophotometry and LC-ESI-(Qq-TOF-MS, enabling the identification of some intermediates. No isatin-5-sulfonic acid was detected after a 60 min photocatalytic reaction, and three sulfonated aromatic amines, including 4-amino-3-hydroxybenzenesulfonic acid, 2-(2-amino-5-sulfophenyl-2-oxoacetic acid and 2-amino-5-sulfobenzoic acid, were present in the reaction mixture.

  18. TiO2 Immobilized on Manihot Carbon: Optimal Preparation and Evaluation of Its Activity in the Decomposition of Indigo Carmine

    Science.gov (United States)

    Antonio-Cisneros, Cynthia M.; Dávila-Jiménez, Martín M.; Elizalde-González, María P.; García-Díaz, Esmeralda

    2015-01-01

    Applications of carbon-TiO2 materials have attracted attention in nanotechnology due to their synergic effects. We report the immobilization of TiO2 on carbon prepared from residues of the plant Manihot, commercial TiO2 and glycerol. The objective was to obtain a moderate loading of the anatase phase by preserving the carbonaceous external surface and micropores of the composite. Two preparation methods were compared, including mixing dry precursors and immobilization using a glycerol slurry. The evaluation of the micropore blocking was performed using nitrogen adsorption isotherms. The results indicated that it was possible to use Manihot residues and glycerol to prepare an anatase-containing material with a basic surface and a significant SBET value. The activities of the prepared materials were tested in a decomposition assay of indigo carmine. The TiO2/carbon eliminated nearly 100% of the dye under UV irradiation using the optimal conditions found by a Taguchi L4 orthogonal array considering the specific surface, temperature and initial concentration. The reaction was monitored by UV-Vis spectrophotometry and LC-ESI-(Qq)-TOF-MS, enabling the identification of some intermediates. No isatin-5-sulfonic acid was detected after a 60 min photocatalytic reaction, and three sulfonated aromatic amines, including 4-amino-3-hydroxybenzenesulfonic acid, 2-(2-amino-5-sulfophenyl)-2-oxoacetic acid and 2-amino-5-sulfobenzoic acid, were present in the reaction mixture. PMID:25588214

  19. TiO2 immobilized on Manihot carbon: optimal preparation and evaluation of its activity in the decomposition of indigo carmine.

    Science.gov (United States)

    Antonio-Cisneros, Cynthia M; Dávila-Jiménez, Martín M; Elizalde-González, María P; García-Díaz, Esmeralda

    2015-01-12

    Applications of carbon-TiO2 materials have attracted attention in nanotechnology due to their synergic effects. We report the immobilization of TiO2 on carbon prepared from residues of the plant Manihot, commercial TiO2 and glycerol. The objective was to obtain a moderate loading of the anatase phase by preserving the carbonaceous external surface and micropores of the composite. Two preparation methods were compared, including mixing dry precursors and immobilization using a glycerol slurry. The evaluation of the micropore blocking was performed using nitrogen adsorption isotherms. The results indicated that it was possible to use Manihot residues and glycerol to prepare an anatase-containing material with a basic surface and a significant SBET value. The activities of the prepared materials were tested in a decomposition assay of indigo carmine. The TiO2/carbon eliminated nearly 100% of the dye under UV irradiation using the optimal conditions found by a Taguchi L4 orthogonal array considering the specific surface, temperature and initial concentration. The reaction was monitored by UV-Vis spectrophotometry and LC-ESI-(Qq)-TOF-MS, enabling the identification of some intermediates. No isatin-5-sulfonic acid was detected after a 60 min photocatalytic reaction, and three sulfonated aromatic amines, including 4-amino-3-hydroxybenzenesulfonic acid, 2-(2-amino-5-sulfophenyl)-2-oxoacetic acid and 2-amino-5-sulfobenzoic acid, were present in the reaction mixture.

  20. Preparation of flat carbon support films

    NARCIS (Netherlands)

    Koning, RI; Oostergetel, GT; Brisson, A

    Wrinkling of carbon support films is known to limit the resolution of electron microscopy images of protein two-dimensional crystals. The origin of carbon wrinkling during preparation of the support films was investigated by reflected light microscopy. We observed that carbon films go through

  1. Evaluation of removal efficiency of heavy metals by low-cost activated carbon prepared from African palm fruit

    Science.gov (United States)

    Abdulrazak, Sani; Hussaini, K.; Sani, H. M.

    2017-10-01

    This study details the removal of heavy metals; Cadmium, Copper, Nickel, and Lead from wastewater effluent using an activated carbon produced from African palm fruit. The effluent was obtained from Old Panteka market; a metal scrap Market located in Kaduna State, Nigeria, which has several components that constitute high level of pollution in the environment. The effect of temperature and contact time on the removal of these heavy metals using the activated carbon produced was investigated. The activated carbon showed a significant ability in removing heavy metals; Cadmium, Copper, Nickel, and Lead from the wastewater. Higher percentage removal was observed at a temperature of 80 °C (93.23 ± 0.035, 96.71 ± 0.097, 92.01 ± 0.018, and 95.42 ± 0.067 % for Cadmium, Copper, Nickel, and Lead, respectively) and at an optimum contact time of 60 min (99.235 ± 0.148, 96.711 ± 0.083, 95.34 ± 0.015, and 97.750 ± 0.166 % for Cadmium, Copper, Nickel, and Lead, respectively) after which the percentage removal decreases. This work, therefore, suggests that African palm fruit can be successfully applied to solve this environmental pollution.

  2. Preparation of PtRu/carbon hybrids by hydrothermal carbonization process

    OpenAIRE

    Marcelo Marques Tusi; Michele Brandalise; Olandir Vercino Correa; Almir Oliveira Neto; Marcelo Linardi; Estevam Vitorio Spinacé

    2007-01-01

    PtRu/Carbon hybrids were prepared by hydrothermal carbonization process using glucose or starch as carbon sources and reducing agents and platinum and ruthenium salts as catalysts of carbonization process and metals source. The obtained PtRu/Carbon materials were characterized by SEM/EDX, TGA, XRD and cyclic voltammetry. The electro-oxidation of methanol was studied by cyclic voltammetry using the thin porous coating technique aiming fuel cell application. The catalytic activity was dependent...

  3. Preparation, Characterization, and In Vitro and Vivo Antitumor Activity of Oridonin-Conjugated Multiwalled Carbon Nanotubes Functionalized with Carboxylic Group

    Directory of Open Access Journals (Sweden)

    Chuanjin Wang

    2016-01-01

    Full Text Available Carbon nanotubes have shown great potential in tumor therapy. Oridonin (ORI is a poorly water-soluble diterpenoid compound (C20H28O6 used in the treatment of esophageal and hepatic carcinoma for decades. For the purpose of enhancing the antitumor potency and reducing cytotoxicity of ORI, multiwalled carbon nanotubes functionalized with carboxylic group (MWCNTs-COOH were used as ORI carrier. ORI was noncovalently encapsulated into (or onto the functionalized carbon nanotubes (MWCNTs-ORI. The obtained MWCNTs-ORI has been characterized. The ORI loading efficiency in MWCNTs-COOH carrier was studied to be about 82.6% (w/w. In vitro cytotoxicity assay on MWCNTs-ORI gave IC50 of 7.29±0.5 μg/mL and ORI-F gave IC50 of 14.5±1.4 μg/mL. The antitumor effect studies in vivo showed that MWCNTs-ORI improved antitumor activity of ORI in comparison with ORI-F. The tumor inhibition ratio for MWCNTs-ORI (1.68×10-2 g·Kg−1·d−1 was 86.4%, higher than that of ORI-F (1.68×10-2 g·Kg−1·d−1 which was 39.2%. This can greatly improve the pharmaceutical efficiency and reduce potential side effects.

  4. Porous carbons prepared by direct carbonization of MOFs for supercapacitors

    Science.gov (United States)

    Yan, Xinlong; Li, Xuejin; Yan, Zifeng; Komarneni, Sridhar

    2014-07-01

    Three porous carbons were prepared by direct carbonization of HKUST-1, MOF-5 and Al-PCP without additional carbon precursors. The carbon samples obtained by carbonization at 1073 K were characterized by XRD, TEM and N2 physisorption techniques followed by testing for electrochemical performance. The BET surface areas of the three carbons were in the range of 50-1103 m2/g. As electrode materials for supercapacitor, the MOF-5 and Al-PCP derived carbons displayed the ideal capacitor behavior, whereas the HKUST-1 derived carbon showed poor capacitive behavior at various sweep rates and current densities. Among those carbon samples, Al-PCP derived carbons exhibited highest specific capacitance (232.8 F/g) in 30% KOH solution at the current density of 100 mA/g.

  5. Carbon membranes: Precursor, preparation, and functionalization

    NARCIS (Netherlands)

    Barsema, J.N.

    2004-01-01

    In this thesis we study the preparation of Carbon Molecular Sieve (CMS) membranes for the separation of gases. The gases are separated based on their size difference and affinity for the membrane material.

  6. Preparation and use of maize tassels' activated carbon for the adsorption of phenolic compounds in environmental waste water samples.

    Science.gov (United States)

    Olorundare, O F; Msagati, T A M; Krause, R W M; Okonkwo, J O; Mamba, B B

    2015-04-01

    The determination and remediation of three phenolic compounds bisphenol A (BPA), ortho-nitrophenol (o-NTP), parachlorophenol (PCP) in wastewater is reported. The analysis of these molecules in wastewater was done using gas chromatography (GC) × GC time-of-flight mass spectrometry while activated carbon derived from maize tassel was used as an adsorbent. During the experimental procedures, the effect of various parameters such as initial concentration, pH of sample solution, eluent volume, and sample volume on the removal efficiency with respect to the three phenolic compounds was studied. The results showed that maize tassel produced activated carbon (MTAC) cartridge packed solid-phase extraction (SPE) system was able to remove the phenolic compounds effectively (90.84-98.49%, 80.75-97.11%, and 78.27-97.08% for BPA, o-NTP, and PCP, respectively). The MTAC cartridge packed SPE sorbent performance was compared to commercially produced C18 SPE cartridges and found to be comparable. All the parameters investigated were found to have a notable influence on the adsorption efficiency of the phenolic compounds from wastewaters at different magnitudes.

  7. Enhanced visible-light photocatalytic H2-generation activity of carbon/g-C3N4 nanocomposites prepared by two-step thermal treatment.

    Science.gov (United States)

    Xu, Quanlong; Jiang, Chuanjia; Cheng, Bei; Yu, Jiaguo

    2017-08-15

    Photocatalytic hydrogen (H2) production from water by using solar energy and a photocatalyst is a green and sustainable route to tackle the energy issues. Herein, carbon/g-C3N4 nanocomposites were successfully synthesized via a two-step thermal treatment of urea and glucose with different ratios. As confirmed by X-ray photoelectron spectroscopy, a C-O-C bond was formed between carbon and g-C3N4, which leads to a strong interaction between carbon and g-C3N4. The prepared samples were evaluated for photocatalytic H2 generation under visible light irradiation. The experimental results indicate that the carbon/g-C3N4 nanocomposites show great photocatalytic H2 evolution activity, as high as 410.1 μmol g(-1) h(-1), which is 13.6-fold of pure g-C3N4. The enhanced photocatalytic performance not only originates from the enlarged surface area and extended visible light response range, but also from the effectively separated photo-generated charge carriers. This spatial charge separation greatly suppresses the recombination of photo-generated hole-electron pairs and facilitates efficient H2 production. This work provides a facile way to design highly efficient carbon nitride-based photocatalysts for potential application in photocatalytic reaction by using solar energy.

  8. Comparison of ultrasonic with stirrer performance for removal of sunset yellow (SY) by activated carbon prepared from wood of orange tree: artificial neural network modeling.

    Science.gov (United States)

    Ghaedi, A M; Ghaedi, M; Karami, P

    2015-03-05

    The present work focused on the removal of sunset yellow (SY) dye from aqueous solution by ultrasound-assisted adsorption and stirrer by activated carbon prepared from wood of an orange tree. Also, the artificial neural network (ANN) model was used for predicting removal (%) of SY dye based on experimental data. In this study a green approach was described for the synthesis of activated carbon prepared from wood of an orange tree and usability of it for the removal of sunset yellow. This material was characterized using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The impact of variables, including initial dye concentration (mg/L), pH, adsorbent dosage (g), sonication time (min) and temperature (°C) on SY removal were studied. Fitting the experimental equilibrium data of different isotherm models such as Langmuir, Freundlich, Temkin and Dubinin-Radushkevich models display the suitability and applicability of the Langmuir model. Analysis of experimental adsorption data by different kinetic models including pseudo-first and second order, Elovich and intraparticle diffusion models indicate the applicability of the second-order equation model. The adsorbent (0.5g) is applicable for successful removal of SY (>98%) in short time (10min) under ultrasound condition. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Comparison of ultrasonic with stirrer performance for removal of sunset yellow (SY) by activated carbon prepared from wood of orange tree: Artificial neural network modeling

    Science.gov (United States)

    Ghaedi, A. M.; Ghaedi, M.; Karami, P.

    2015-03-01

    The present work focused on the removal of sunset yellow (SY) dye from aqueous solution by ultrasound-assisted adsorption and stirrer by activated carbon prepared from wood of an orange tree. Also, the artificial neural network (ANN) model was used for predicting removal (%) of SY dye based on experimental data. In this study a green approach was described for the synthesis of activated carbon prepared from wood of an orange tree and usability of it for the removal of sunset yellow. This material was characterized using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The impact of variables, including initial dye concentration (mg/L), pH, adsorbent dosage (g), sonication time (min) and temperature (°C) on SY removal were studied. Fitting the experimental equilibrium data of different isotherm models such as Langmuir, Freundlich, Temkin and Dubinin-Radushkevich models display the suitability and applicability of the Langmuir model. Analysis of experimental adsorption data by different kinetic models including pseudo-first and second order, Elovich and intraparticle diffusion models indicate the applicability of the second-order equation model. The adsorbent (0.5 g) is applicable for successful removal of SY (>98%) in short time (10 min) under ultrasound condition.

  10. Preparation and Characterization of the Activated Carbon-Nylon Beads: Novel Material for In Situ Microbe Sampler and Microcosm Experiment in Groundwater Environment

    Science.gov (United States)

    Liu, J.; Liu, H.

    2015-12-01

    The organic pollution of groundwater is a widespread problem in the word. It is significant to study the microbial community especially related to organic contaminant biodegradation and their variation with groundwater environment parameters, so as to evaluate the biodegradability of the organic contaminants and then make a right decision for bioremediation. One of good ways for this study is to build a microcosm in groundwater containing target contaminant, where microbes especially relating to biodegradation will grow in the microcosm and be collected for analysis. This research aims to prepare a novel material for in situ microbe sampler and microcosm experiment in groundwater environment. The novel material, namely, the activated carbon-nylon (AC-N) beads, was prepared using activated carbon and nylon as main raw materials. The material consists of 3-4mm diameter spherical beads (Fig.1A and Fig.2 A) which have an internal surface area greater than 500 m2 g-1. FT-IR spectra (Fig.3) indicated the composition of activated carbon and nylon due to the variation of the peaks at the near 1627 cm-1and 1558 -1538 cm-1 before and after complex reaction. The equilibrium adsorption capacity of benzene on the beads was 16.76 mg/g at the initial concentration of 100 mg/L. The adsorption kinetics was found to follow the pseudo-second-order kinetic model (Fig.4). The mechanism of the adsorption process was determined from the intraparticle diffusion model. Camera and SEM images (Fig.1 B and Fig.2 A and B) showed that the beads had an open and channel pore structures, the microbes might enter into and grow up in the beads (Fig.1 C and Fig.2 C). All these results showed that the AC-N beads could form the in situ microcosm of organic pollutants and microbes, which provided a promising prospect for assessing the biodegradability of the organic pollutants by intrinsic microbes in the groundwater.

  11. Optimization of process condition for the preparation of amine-impregnated activated carbon developed for CO2capture and applied to methylene blue adsorption by response surface methodology.

    Science.gov (United States)

    Das, Dipa; Meikap, Bhim C

    2017-10-15

    The present research describes the optimal adsorption condition for methylene blue (MB). The adsorbent used here was monoethanol amine-impregnated activated carbon (MEA-AC) prepared from green coconut shell. Response surface methodology (RSM) is the multivariate statistical technique used for the optimization of the process variables. The central composite design is used to determine the effect of activation temperature, activation time and impregnation ratio on the MB removal. The percentage (%) MB adsorption by MEA-AC is evaluated as a response of the system. A quadratic model was developed for response. From the analysis of variance, the factor which was the most influential on the experimental design response has been identified. The optimum condition for the preparation of MEA-AC from green coconut shells is the temperature of activation 545.6°C, activation time of 41.64 min and impregnation ratio of 0.33 to achieve the maximum removal efficiency of 98.21%. At the same optimum parameter, the % MB removal from the textile-effluent industry was examined and found to be 96.44%.

  12. Co-pyrolysis behaviour and kinetic of two typical solid wastes in China and characterisation of activated carbon prepared from pyrolytic char.

    Science.gov (United States)

    Ma, Yuhui; Niu, Ruxuan; Wang, Xiaona; Wang, Qunhui; Wang, Xiaoqiang; Sun, Xiaohong

    2014-11-01

    This is the first study on the co-pyrolysis of spent substrate of Pleurotus ostreatus and coal tar pitch, and the activated carbon prepared from the pyrolytic char. Thermogravimetry (TG) analysis was carried out taking spent substrate, coal tar pitch and spent substrate-coal tar pitch mixture. The activation energies of pyrolysis reactions were obtained via the Flynn-Wall-Ozawa and Kissinger-Akahira-Sunose methods. The kinetic models were determined by the master-plots method. The activated carbons were characterised by N2-adsorption, Fourier transform infrared spectroscopy and X-ray diffraction. Experimental results demonstrated a synergistic effect happened during co-pyrolysis, which was characterised by a decreased maximum decomposition rate and an enhanced char yield. The average activation energies of the pyrolysis reactions of spent substrate, coal tar pitch and the mixture were 115.94, 72.92 and 94.38 kJ mol(-1) for the Flynn-Wall-Ozawa method, and 112.17, 65.62 and 89.91 kJ mol(-1) for the Kissinger-Akahira-Sunose method. The reaction model functions were f(α) = (1-α)(3.42), (1-α)(1.72) and (1-α)(3.07) for spent substrate, coal tar pitch and the mixture, respectively. The mixture char-derived activated carbon had a Brunauer-Emmett-Teller surface area up to 1337 m(2) g(-1) and a total pore volume of 0.680 cm(3) g(-1). Mixing spent substrate with coal tar pitch led to the creation of more micropores and a higher surface area compared with the single spent substrate and coal tar pitch char. Also, the mixture char-derived activated carbon had a higher proportion of aromatic stacking. This study provides a reference for the utilisation of spent substrate and coal tar pitch via co-pyrolysis, and their pyrolytic char as a promising precursor of activated carbon. © The Author(s) 2014.

  13. Removal of fluoride from drinking water using aluminum hydroxide coated activated carbon prepared from bark of Morinda tinctoria

    Science.gov (United States)

    Amalraj, Augustine; Pius, Anitha

    2017-10-01

    The aim of this study is to design and develop a novel cost effective method for fluoride removal, applicable to rural areas of developing countries. Adsorption is widely considered as one of the appropriate technologies for water defluoridation. This study investigates the feasibility of using low-cost biomass based activated carbon from the bark of Morinda tinctoria coated with aluminum hydroxide (AHAC) for water defluoridation, at neutral pH range. Characterization of AHAC was done through IR, SEM with EDAX studies before and after fluoride treatment. The fluoride adsorption capacity of AHAC as a function of contact time, pH and initial fluoride concentration was investigated. The role of co-existing interfering ions also was studied. The isotherm and kinetic models were used to understand the nature of the fluoride adsorption onto AHAC. Freundlich isotherm and intra-particle diffusion were the best-fitting models for the adsorption of fluoride on AHAC. Fluoride adsorption kinetics well fitted with pseudo-second order model. The results showed excellent fluoride adsorption capacity was found to be 26.03 mg g-1 at neutral pH.

  14. Carbon particle induced foaming of molten sucrose for the preparation of carbon foams

    Energy Technology Data Exchange (ETDEWEB)

    Narasimman, R.; Vijayan, Sujith; Prabhakaran, K., E-mail: kp2952002@gmail.com

    2014-11-15

    Graphical abstract: - Highlights: • An easy method for the preparation of carbon foam from sucrose is presented. • Wood derived activated carbon particles are used to stabilize the molten sucrose foam. • The carbon foams show relatively good mechanical strength. • The carbon foams show excellent CO{sub 2} adsorption and oil absorption properties. • The process could be scaled up for the preparation of large foam bodies. - Abstract: Activated carbon powder was used as a foaming and foam setting agent for the preparation of carbon foams with a hierarchical pore structure from molten sucrose. The rheological measurements revealed the interruption of intermolecular hydrogen bonding in molten sucrose by the carbon particles. The carbon particles stabilized the bubbles in molten sucrose by adsorbing on the molten sucrose–gas interface. The carbon foams obtained at the activated carbon powder to sucrose weight ratios in the range of 0–0.25 had a compressive strength in the range of 1.35–0.31 MPa. The produced carbon foams adsorb 2.59–3.04 mmol/g of CO{sub 2} at 760 mmHg at 273 K and absorb oil from oil–water mixtures and surfactant stabilized oil-in-water emulsions with very good selectivity and recyclability.

  15. Preparation of nitrogen-doped carbon tubes

    Science.gov (United States)

    Chung, Hoon Taek; Zelenay, Piotr

    2015-12-22

    A method for synthesizing nitrogen-doped carbon tubes involves preparing a solution of cyanamide and a suitable transition metal-containing salt in a solvent, evaporating the solvent to form a solid, and pyrolyzing the solid under an inert atmosphere under conditions suitable for the production of nitrogen-doped carbon tubes from the solid. Pyrolyzing for a shorter period of time followed by rapid cooling resulted in a tubes with a narrower average diameter.

  16. Sorption properties of the activated carbon-zeolite composite prepared from coal fly ash for Ni(2+), Cu(2+), Cd(2+) and Pb(2+).

    Science.gov (United States)

    Jha, Vinay Kumar; Matsuda, Motohide; Miyake, Michihiro

    2008-12-15

    Composite materials of activated carbon and zeolite have been prepared successfully by activating coal fly ash (CFA) by fusion with NaOH at 750 degrees C in N(2) followed by hydrothermal treatments under various conditions. Uptake experiments for Ni(2+), Cu(2+), Cd(2+) and Pb(2+) were performed with the materials thus obtained from CFA. Of the various composite materials, that were obtained by hydrothermal treatment with NaOH solution (ca. 4M) at 80 degrees C (a composite of activated carbon and zeolite X/faujasite) proved to be the most suitable for the uptake of toxic metal ions. The relative selectivity of the present sorbents for the various ions was Pb(2+)>Cu(2+)>Cd(2+)>Ni(2+), with equilibrium uptake capacities of 2.65, 1.72, 1.44 and 1.20mmol/g, respectively. The sorption isotherm was a good fit to the Langmuir isotherm and the sorption is thought to progress mainly by ion exchange with Na(+). The overall reaction is pseudo-second order with rate constants of 0.14, 0.17, 0.21 and 0.20Lg/mmol min for the uptake of Pb(2+), Cu(2+), Cd(2+) and Ni(2+), respectively.

  17. Optimization of preparation conditions for activated carbon from banana pseudo-stem using response surface methodology on removal of color and COD from landfill leachate.

    Science.gov (United States)

    Ghani, Zaidi Ab; Yusoff, Mohd Suffian; Zaman, Nastaein Qamaruz; Zamri, Mohd Faiz Muaz Ahmad; Andas, Jeyashelly

    2017-04-01

    This study determined the optimum conditions for preparation and adsorptive treatment of landfill leachate from banana pseudo-stem based activated carbon. Response surface methodology (RSM) based on Box-Behnken was applied to optimize the combination effect of three important reaction variables, i.e. activation temperature (°C), activation time and impregnation ratio (IR). The reaction was performed via a single step activation with ZnCl2 in a closed activation system. A series of 17 individual experiments were conducted and the results showed that the RSM based on BBD is very applicable for adsorptive removal of pollutants from landfill leachate treatment. The optimum conditions obtained by Design of Experiments (DOE) was at 761°C activation temperature, 87min activation time and 4.5g/g impregnation ratio with product yield (27%), iodine number (1101mg/g), color removal (91.2%) and COD removal (83.0%). Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Application of least squares support vector regression and linear multiple regression for modeling removal of methyl orange onto tin oxide nanoparticles loaded on activated carbon and activated carbon prepared from Pistacia atlantica wood.

    Science.gov (United States)

    Ghaedi, M; Rahimi, Mahmoud Reza; Ghaedi, A M; Tyagi, Inderjeet; Agarwal, Shilpi; Gupta, Vinod Kumar

    2016-01-01

    Two novel and eco friendly adsorbents namely tin oxide nanoparticles loaded on activated carbon (SnO2-NP-AC) and activated carbon prepared from wood tree Pistacia atlantica (AC-PAW) were used for the rapid removal and fast adsorption of methyl orange (MO) from the aqueous phase. The dependency of MO removal with various adsorption influential parameters was well modeled and optimized using multiple linear regressions (MLR) and least squares support vector regression (LSSVR). The optimal parameters for the LSSVR model were found based on γ value of 0.76 and σ(2) of 0.15. For testing the data set, the mean square error (MSE) values of 0.0010 and the coefficient of determination (R(2)) values of 0.976 were obtained for LSSVR model, and the MSE value of 0.0037 and the R(2) value of 0.897 were obtained for the MLR model. The adsorption equilibrium and kinetic data was found to be well fitted and in good agreement with Langmuir isotherm model and second-order equation and intra-particle diffusion models respectively. The small amount of the proposed SnO2-NP-AC and AC-PAW (0.015 g and 0.08 g) is applicable for successful rapid removal of methyl orange (>95%). The maximum adsorption capacity for SnO2-NP-AC and AC-PAW was 250 mg g(-1) and 125 mg g(-1) respectively. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. In situ preparation of calcium carbonate films

    Energy Technology Data Exchange (ETDEWEB)

    Dahle, S. [Clausthaler Zentrum fuer Materialtechnik, Technische Universitaet Clausthal, Leibnizstrasse 4, 38678 Clausthal-Zellerfeld (Germany); Institut fuer Physik und Physikalische Technologien, Technische Universitaet Clausthal, Leibnizstrasse 4, 38678 Clausthal-Zellerfeld (Germany); Voigts, F. [Institut fuer Physik und Physikalische Technologien, Technische Universitaet Clausthal, Leibnizstrasse 4, 38678 Clausthal-Zellerfeld (Germany); Maus-Friedrichs, W., E-mail: w.maus-friedrichs@pe.tu-clausthal.de [Clausthaler Zentrum fuer Materialtechnik, Technische Universitaet Clausthal, Leibnizstrasse 4, 38678 Clausthal-Zellerfeld (Germany); Institut fuer Physik und Physikalische Technologien, Technische Universitaet Clausthal, Leibnizstrasse 4, 38678 Clausthal-Zellerfeld (Germany)

    2012-01-01

    The in situ preparation of calcium carbonate films in an ultra high vacuum (UHV) is inhibited by the decomposition of CO{sub 2} molecules at the surface and the absence of CO{sub 2} bulk diffusion. Therefore, it is not possible to prepare such films simply by CO{sub 2} exposure to a calcium layer. We investigated different approaches for the preparation of CaCO{sub 3} films in an UHV. Among these, only the simultaneous evaporation of Ca atoms in a mixed O{sub 2} and CO{sub 2} atmosphere is able to produce well defined stoichiometric calcium carbonate films. Metastable Induced Electron Spectroscopy, Ultraviolet Photoelectron Spectroscopy and X-ray Photoelectron Spectroscopy are employed to verify quality and purity of the films.

  20. Preparation of nitrogen-doped cotton stalk microporous activated carbon fiber electrodes with different surface area from hexamethylenetetramine-modified cotton stalk for electrochemical degradation of methylene blue

    Science.gov (United States)

    Li, Kunquan; Rong, Zhang; Li, Ye; Li, Cheng; Zheng, Zheng

    Cotton-stalk activated carbon fibers (CSCFs) with controllable micropore area and nitrogen content were prepared as an efficient electrode from hexamethylenetetramine-modified cotton stalk by steam/ammonia activation. The influence of microporous area, nitrogen content, voltage and initial concentration on the electrical degradation efficiency of methylene blue (MB) was evaluated by using CSCFs as anode. Results showed that the CSCF electrodes exhibited excellent MB electrochemical degradation ability including decolorization and COD removal. Increasing micropore surface area and nitrogen content of CSCF anode leaded to a corresponding increase in MB removal. The prepared CSCF-800-15-N, which has highest N content but lowest microporous area, attained the best degradation effect with 97% MB decolorization ratio for 5 mg/L MB at 12 V in 4 h, implying the doped nitrogen played a prominent role in improving the electrochemical degradation ability. The electrical degradation reaction was well described by first-order kinetics model. Overall, the aforesaid findings suggested that the nitrogen-doped CSCFs were potential electrode materials, and their electrical degradation abilities could be effectively enhanced by controlling the nitrogen content and micropore surface area.

  1. Preparation of a novel PAN/cellulose acetate-Ag based activated carbon nanofiber and its adsorption performance for low-concentration SO2

    Science.gov (United States)

    Wu, Yan-bo; Bi, Jun; Lou, Ting; Song, Tie-ben; Yu, Hong-quan

    2015-04-01

    Polyacrylonitrile (PAN), PAN/cellulose acetate (CA), and PAN/CA-Ag based activated carbon nanofiber (ACNF) were prepared using electrostatic spinning and further heat treatment. Thermogravimetry-differential scanning calorimetry (TG-DSC) analysis indicated that the addition of CA or Ag did not have a significant impact on the thermal decomposition of PAN materials but the yields of fibers could be improved. Scanning electron microscopy (SEM) analysis showed that the micromorphologies of produced fibers were greatly influenced by the viscosity and conductivity of precursor solutions. Fourier transform infrared spectroscopy (FT-IR) analysis proved that a cyclized or trapezoidal structure could form and the carbon scaffold composed of C=C bonds appeared in the PAN-based ACNFs. The characteristic diffraction peaks in X-ray diffraction (XRD) spectra were the evidence of a turbostratic structure and silver existed in the PAN/CA-Ag based ACNF. Brunner-Emmett-Teller (BET) analysis showed that the doping of CA and Ag increased surface area and micropore volume of fibers; particularly, PAN/CA-Ag based ACNF exhibited the best porosity feature. Furthermore, SO2 adsorption experiments indicated that all the three fibers had good adsorption effects on lower concentrations of SO2 at room temperature; especially, the PAN/CA-Ag based ACNF showed the best adsorption performance, and it may be one of the most promising adsorbents used in the fields of chemical industry and environment protection.

  2. Preparation of highly developed mesoporous activated carbon fiber from liquefied wood using wood charcoal as additive and its adsorption of methylene blue from solution.

    Science.gov (United States)

    Ma, Xiaojun; Zhang, Fan; Zhu, Junyan; Yu, Lili; Liu, Xinyan

    2014-07-01

    Activated carbon fiber (C-WACF) with super high surface area and well-developed small mesopores were prepared by liquefied wood and uses wood charcoal (WC) as additive. The characterization and properties of C-WACF were investigated by XRD, XPS and N2 adsorption. Results showed the pore development was significant at temperatures >750°C, and reached a maximum BET surface area (2604.7 m(2)/g) and total pore volume (1.433 cm(3)/g) at 850°C, of which 86.8% was from the contribution of the small mesopores of 2-4 nm. It was also found that the mesopore volume and methylene blue adsorption of C-WACF were highly increased as the temperature increases from 750 to 850°C. Additionally, the reduction of graphitic layers, the obvious changes of functional groups and the more unstable carbons on the surface of C-WACF, which played important roles in the formation of mesopores, were also observed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Preparation and characterization of corn cob activated carbon coated with nano-sized magnetite particles for the removal of Cr(VI).

    Science.gov (United States)

    Nethaji, S; Sivasamy, A; Mandal, A B

    2013-04-01

    Activated carbon prepared from corn cob biomass, magnetized by magnetite nanoparticles (MCCAC) was used for the adsorption of hexavalent chromium from aqueous solution. The adsorbent was characterized by SEM, TEM, XRD, VSM, surface functionality and zero-point charge. The iron oxide nanoparticles were of 50 nm sizes and the saturation magnetization value for the adsorbent is 48.43 emu/g. Adsorption was maximum at pH 2. Isotherm data were modeled using Langmuir, Freundlich and Temkin isotherm. The prepared MCCAC had a heterogeneous surface. The maximum monolayer adsorption capacity was 57.37 mg/g. Kinetic studies were carried out and the data fitted the pseudo second-order equation. The mechanism of the adsorption process was studied by incorporating the kinetic data with intraparticle diffusion model, Bangham equation and Boyd plot. The adsorption was by chemisorption and the external mass transfer was the rate-determining step. A micro column was designed and the basic column parameters were estimated. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Preparation of activated carbon from doum stone and its application on adsorption of 60Co and 152+154Eu: Equilibrium, kinetic and thermodynamic studies.

    Science.gov (United States)

    Hamed, Mostafa M; Ali, M M S; Holiel, M

    2016-11-01

    Removal of radionuclides from wastewater before discharging to environment is necessary for the safety of living beings. Activated carbon prepared from doum stone (DS), an agricultural waste by-product, has been used for the sorption of 60Co and 152+154Eu radionuclides from aqueous solutions. DS has been characterized by different analytical tools. The efficiency of the adsorbent was investigated using batch sorption technique under different experimental conditions. The equilibrium sorption data were analyzed using Freundlich and Langmuir isotherm models. The kinetic experimental data were analyzed using four kinetic models including pseudo-first order, pseudo-second order, Elovich and intraparticle diffusion model to examine the mechanism of sorption and potential rate-controlling step. The maximum capacity of DS was found to be 121 mg/g and 166 mg/g for cobalt and europium, respectively. Sorption efficiency of DS to remove 60Co, 152+154Eu and 134Cs from real radioactive wastewater and environmental (river water and sea water) samples was also investigated. The results revealed that the prepared DS as low cost could be used as a promising material for the simultaneous removal of different radionuclides such as 60Co, 152+154Eu and 134Cs, or trivalent actinides such as 241, 242m,243Am from real radioactive waste and environmental water samples. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Preparation of Co-Mo catalyst using activated carbon produced from egg shell and SiO2 as support – A hydrogenation study

    OpenAIRE

    Adeniyi Sunday Ogunlaja; Alade, Olalekan S.; Funmilola Y. Oladipo

    2010-01-01

    The preparation of a series of cobalt-molybdenum (Co-Mo) catalysts supported on SiO2 and carbonized egg shells were investigated using standard procedures; the catalysts were further calcined at the 500 oC temperature to generate the internally consistent set, and the metal atoms content were varied in a regular manner. The ratio 1:4 (Co2+: Mo6+) by weight was employed for the various catalysts prepared. The carbonized egg shells were divided into two parts: the first part was leached with HN...

  6. nanoparticles-decorated activated carbon nanocomposite based ...

    Indian Academy of Sciences (India)

    T K APARNA

    2018-02-07

    decorated activated carbon. (AC) nanocomposite for selective detection of dopamine (DA) in the presence of uric acid (UA) and ascorbic acid (AA). The nanocomposite was prepared by a simple hydrothermal method and the ...

  7. Preference of multi-walled carbon nanotube (MWCNT) to single-walled carbon nanotube (SWCNT) and activated carbon for preparing silica nanohybrid pickering emulsion for chemical enhanced oil recovery (C-EOR)

    Energy Technology Data Exchange (ETDEWEB)

    AfzaliTabar, M. [Department of Chemistry, Islamic Azad University Branch of Tehran North, Tehran (Iran, Islamic Republic of); Alaei, M., E-mail: alaiem@ripi.ir [Nanotechnology Research Center, Research Institute of Petroleum Industry (RIPI), Tehran (Iran, Islamic Republic of); Ranjineh Khojasteh, R.; Motiee, F. [Department of Chemistry, Islamic Azad University Branch of Tehran North, Tehran (Iran, Islamic Republic of); Rashidi, A.M. [Nanotechnology Research Center, Research Institute of Petroleum Industry (RIPI), Tehran (Iran, Islamic Republic of)

    2017-01-15

    The aim of this research was to determine the best nano hybrid that can be used as a Pickering emulsion Chemical Enhanced Oil Recovery (C-EOR). Therefore, we have prepared different carbon structures nano hybrids with SiO{sub 2} nano particles with different weight percent using sol-gel method. The as-prepared nano materials were characterized with X-Ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FE-SEM) and Thermal Gravimetric Analysis (TGA). Pickering emulsions of these nanohybrids were prepared at pH=7 in ambient temperature and with distilled water. Stability of the mentioned Pickering emulsions was controlled for one month. Emulsion phase morphology was investigated using optical microscopic imaging. Evaluation results demonstrated that the best sample is the 70% MWCNT/SiO{sub 2} nanohybrid. Stability of the selected nanohybrid (70% MWCNT/SiO{sub 2} nanohybrid) was investigated by alteration of salinity, pH and temperature. Results showed that the mentioned Pickering emulsion has very good stability at 0.1%, 1% salinity, moderate and high temperature (25 °C and 90 °C) and neutral and alkaline pH (7, 10) that is suitable for the oil reservoirs conditions. The effect of the related nano fluid on the wettability of carbonate rock was investigated by measuring the contact angle and interfacial tension. Results show that the nanofluid could significantly change the wettability of the carbonate rock from oil wet to water wet and can decrease the interfacial tension. Therefore, the 70% MWCNT/SiO{sub 2} nanohybrid Pickering emulsion can be used for Chemical Enhanced Oil Recovery (C-EOR).

  8. Preparation and Capacitive Behavior of Dandelion-Like γ-MnO2 Nanofibre/Activated Carbon Microbeads Composite for the Application of Supercapacitor

    Directory of Open Access Journals (Sweden)

    Li Bai

    2011-01-01

    Full Text Available Dandelion-like γ-manganese dioxide (γ-MnO2 nanofibre/activated carbon microbeads (ACMBs composite is prepared by an in situ coating technique. The structure and morphology of the composite are characterized by scanning electron microscopy and X-ray diffraction. The results show that γ-MnO2 nanofibre is uniformly encapsulated on the surface of ACMB, and the composite finally becomes a dandelion-like microbead. Cyclic voltammetry, galvanostatic current charge/discharge, and cycle life measurements are used to evaluate the electrochemical behaviors of the composite. Since the composite is able to undergo pseudofaradic charge transfer reactions and hereto contributes together with the double-layer effect to the total capacitance of the material, the specific capacitance of the composite is as high as 375.9 F g-1 at a scan rate of 1 mV s-1, which is significantly higher than the pure ACMB. Besides, the capacitance retention of the supercapacitor using the composite as electrode-active material keeps still 93% after 1000 cycles.

  9. Single and competitive adsorption of Cd(II) and Pb(II) from aqueous solution by activated carbon prepared with Salix matsudana Kiodz.

    Science.gov (United States)

    Shu, Yan; Li, Kelin; Song, Jinfeng; Li, Bing; Tang, Chunfang

    2016-12-01

    In this study, Salix matsudana activated carbon (SAC) was prepared by phosphoric acid activation, and the adsorption characteristics of Cd(II) and Pb(II) on SAC in single- and double-component solutions were investigated. In both systems, the adsorption capacities of both ions on SAC increased with the increasing initial pH value and temperature in the solutions, and the adsorption equilibrium was approached at 10 min. The adsorption process was spontaneous, endothermic, and depicted well by the pseudo-second-order adsorption model, and the equilibrium adsorption fitted reasonably well with the Langmuir isotherm. The maximum adsorption capacity (Qm) of Cd(II) and Pb(II) was 58.48 and 59.01 mg/g, respectively, in the single-element systems. However, it reduced to 25.32 and 31.09 mg/g, respectively, in the double-element system. The physicochemical property analysis showed that the specific surface area, total pore volume, and average pore diameter of SAC was 435.65 m2/g, 35.68 mL/g, and 3.86 nm, respectively. The SAC contained groups of -OH, C = O, and P = O. Results suggest that SAC had a good performance for the adsorption of Cd(II) and Pb(II) from solution, and the adsorption selectivity sequence was Pb(II) > Cd(II).

  10. Activities: Preparing for Pythagoras.

    Science.gov (United States)

    Laing, Robert A.

    1989-01-01

    Three worksheets are provided to help secondary students explore relationships among the areas of a variety of similar figures constructed on the sides of right triangles. The activity is extended to include the relationship among the lengths of the sides of the right triangle. Included are several student worksheets. (DC)

  11. Preparation, characterization, and application of activated carbon from low-cost material for the adsorption of tetracycline antibiotic from aqueous solutions.

    Science.gov (United States)

    Takdastan, Afshin; Mahvi, Amir Hossein; Lima, Eder C; Shirmardi, Mohammad; Babaei, Ali Akbar; Goudarzi, Gholamreza; Neisi, Abdolkazem; Heidari Farsani, Mohammad; Vosoughi, Mehdi

    2016-11-01

    In this study, a new zinc chloride (ZnCl2) impregnated activated carbon (Zn-AC) was prepared from oak charcoals as low-cost material and used as adsorbent for tetracycline (TC) adsorption. The Zn-AC was characterized using field emission-scanning electron microscope, powder X-ray diffraction, and CHNS-O analyses. Specific surface area of the adsorbent was also measured using the Brunauer, Emmett and Teller (BET) isotherm model. The TC adsorption onto the Zn-AC was investigated as a function of solution pH, adsorbent dosage, and inorganic cations (Li+, K+, Mg2+, Ca2+, Ni2+, and Fe3+) and anions (HCO3-, NO3- and SO42-) that could interfere in the adsorption of TC. The adsorbate solution pH had no considerable effect on TC adsorption. The adsorption of TC onto the adsorbent was relatively fast and reached the equilibrium after about 120 min. The results showed that all studied cations and anions decreased TC adsorption onto the Zn-AC, but this decrease in TC adsorption was strongly significant for Fe3+ and Ni2+ ions. The general order kinetic model and the Redlich-Peterson isotherm model provided the best fit to the experimental data. The maximum amount of TC adsorbed onto the Zn-AC (Qmax) is 282.06 mg g-1, indicating this adsorbent is a good adsorbent for the removal of TC from aqueous solutions.

  12. Preparation and Characterization of Mn/N Co-Doped TiO2 Loaded on Wood-Based Activated Carbon Fiber and Its Visible Light Photodegradation

    Directory of Open Access Journals (Sweden)

    Xiaojun Ma

    2015-09-01

    Full Text Available Using MnSO4·H2O as manganese source and urea as nitrogen source, Mn/N co-doped TiO2 loaded on wood-based activated carbon fiber (Mn/Ti-N-WACF was prepared by sol–gel method. Mn/Ti-N-WACF with different Mn doping contents was characterized by scanning electron microscopy, X-ray diffraction (XRD and X-ray photoelectron spectroscopies (XPS, and ultraviolet-visible spectrophotometer. Results showed that the loading rate of TiO2 in Mn/Ti-N-WACF was improved by Mn/N co-doping. After calcination at 450 °C, the degree of crystallinity of TiO2 was reduced due to Mn/N co-doption in the resulting Mn/Ti-N-WACF samples, but the TiO2 crystal phase was not changed. XPS spectra revealed that some Ti4+ ions from the TiO2 lattice of Mn/Ti-N-WACF system were substituted by doped Mn. Moreover, new bonds formed within N–Ti–N and Ti–N–O because of the doped N that substituted some oxygen atoms in the TiO2 lattice. Notably, the degradation rate of methylene blue for Mn/Ti-N-WACF was improved because of the co-doped Mn/N under visible-light irradiation.

  13. Preparation of low cost activated carbon from Myrtus communis and pomegranate and their efficient application for removal of Congo red from aqueous solution

    Science.gov (United States)

    Ghaedi, Mehrorang; Tavallali, Hossein; Sharifi, Mahdi; Kokhdan, Syamak Nasiri; Asghari, Alireza

    2012-02-01

    In this research, the potential applicability of activated carbon prepared from Myrtus communis (AC-MC) and pomegranate (AC-PG) as useful adsorbents for the removal of Congo red (CR) from aqueous solutions in batch method was investigated. The effects of pH, contact time, agitation time and amount of adsorbents on removal percentage of Congo red on both adsorbents were examined. Increase in pH up to 6 for AC-MC and pH 7 for AC-PG increase the adsorption percentage (capacity) and reach equilibrium within 30 min of contact time. Fitting the experimental data to conventional isotherm models like Freundlich, Langmuir, Tempkin and Dubinin-Radushkevich show that the experimental data fitted very well to the Freundlich isotherm for AC-MC and Langmuir isotherm for AC-PG. Fitting the experimental data to different kinetic models such as pseudo first-order, pseudo second-order, Elovich and intraparticle diffusion mechanism showed the applicability of a pseudo second-order with involvement of intraparticle diffusion model for interpretation of experimental data for both adsorbents. The adsorption capacity of AC-PG and AC-MC for the removal of CR was found to be 19.231 and 10 mg g -1. These results clearly indicate the efficiency of adsorbents as a low cost adsorbent for treatment of wastewater containing CR.

  14. Preparation and electrocatalytic property of WC/carbon nanotube composite

    Energy Technology Data Exchange (ETDEWEB)

    Li Guohua [State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Hangzhou 310014 (China) and Research Center of Nano Science and Technology, Zhejiang University of Technology, Hangzhou 310014 (China) and School of Chemical Engineering and Material Science, Zhejiang University of Technology, Hangzhou 310014 (China)]. E-mail: nanozjut@zjut.edu.cn; Ma Chunan [State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Hangzhou 310014 (China); Research Center of Nano Science and Technology, Zhejiang University of Technology, Hangzhou 310014 (China); School of Chemical Engineering and Material Science, Zhejiang University of Technology, Hangzhou 310014 (China); Tang Junyan [State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Hangzhou 310014 (China); School of Chemical Engineering and Material Science, Zhejiang University of Technology, Hangzhou 310014 (China); Sheng Jiangfeng [State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Hangzhou 310014 (China); School of Chemical Engineering and Material Science, Zhejiang University of Technology, Hangzhou 310014 (China)

    2007-01-01

    Tungsten carbide/carbon nanotube composite was prepared by surface decoration and in situ reduction-carbonization. The samples were characterized by XRD, SEM, EDS, TEM, HRTEM and BET, respectively. The XRD results show that the sample is composed of carbon nanotube, tungsten carbide and tungsten oxide. The EDS results show that the distribution of tungsten oxide is consistent with that of tungsten carbide. SEM, TEM and HRTEM results show that the tungsten carbide nanoparticle with irregular granule grows on the outside surface of carbon nanotube homogenously. The electrocatalytic activity of the sample for p-nitrophenol reduction was tested by a powder microelectrode in a basic solution. The results show that the electrocatalytic activity of the sample is higher than that of granular tungsten carbide, hollow globe tungsten carbide with mesoporosity and carbon nanotube purified. The improvement of the electrocatalytic activity of the sample can be attributed to its components and composite structure. These results indicate that tungsten carbide/carbon nanotube composite is one of the effective ways to improve the electrocatalytic activity of tungsten carbide.

  15. The effects of autohydrolysis pretreatment on the structural characteristics, adsorptive and catalytic properties of the activated carbon prepared from Eucommia ulmoides Oliver based on a biorefinery process.

    Science.gov (United States)

    Zhu, Ming-Qiang; Wang, Zhi-Wen; Wen, Jia-Long; Qiu, Ling; Zhu, Ya-Hong; Su, Yin-Quan; Wei, Qin; Sun, Run-Cang

    2017-05-01

    Eucommia ulmoides Oliver (EU) wood was consecutively treated by autohydrolysis pretreatment and chemical carbonization post-treatment based on a biorefinery process. Results showed that the optimal condition of the autohydrolysis pretreatment and carbonization process yielded 10.37kg xylooligosaccharides (XOS), 1.39kg degraded hemicellulosic products, 17.29kg other degraded products from hemicelluloses and 40.72kg activated carbon (S BET of 1534.06m 2 /g) from the 100kg raw materials. Simultaneously, 29.14kg gas products generated from the optimum integrated process was significantly lower than that from the direct carbonization process (68.84kg). Besides, the optimal activated carbon (AC 170-1.0 ) also showed a moderate catalytic activity and high stability for hydrogen production by catalytic methane decomposition. Overall, the data presented indicated that the integrated process is an eco-friendly and efficient process to produce XOS and activated carbon, which is beneficial for value-added and industrial application of EU wood. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. ACTIVATED CARBON FROM LIGNITE FOR WATER TREATMENT

    Energy Technology Data Exchange (ETDEWEB)

    Edwin S. Olson; Daniel J. Stepan

    2000-07-01

    High concentrations of humate in surface water result in the formation of excess amounts of chlorinated byproducts during disinfection treatment. These precursors can be removed in water treatment prior to disinfection using powdered activated carbon. In the interest of developing a more cost-effective method for removal of humates in surface water, a comparison of the activities of carbons prepared from North Dakota lignites with those of commercial carbons was conducted. Previous studies indicated that a commercial carbon prepared from Texas lignite (Darco HDB) was superior to those prepared from bituminous coals for water treatment. That the high alkali content of North Dakota lignites would result in favorable adsorptive properties for the very large humate molecules was hypothesized, owing to the formation of larger pores during activation. Since no standard humate test has been previously developed, initial adsorption testing was performed using smaller dye molecules with various types of ionic character. With the cationic dye, methylene blue, a carbon prepared from a high-sodium lignite (HSKRC) adsorbed more dye than the Darco HDB. The carbon from the low-sodium lignite was much inferior. With another cationic dye, malachite green, the Darco HDB was slightly better. With anionic dyes, methyl red and azocarmine-B, the results for the HSKRC and Darco HDB were comparable. A humate test was developed using Aldrich humic acid. The HSKRC and the Darco HDB gave equally high adsorption capacities for the humate (138 mg/g), consistent with the similarities observed in earlier tests. A carbon prepared from a high-sodium lignite from a different mine showed an outstanding improvement (201 mg/g). The carbons prepared from the low-sodium lignites from both mines showed poor adsorption capacities for humate. Adsorption isotherms were performed for the set of activated carbons in the humate system. These exhibited a complex behavior interpreted as resulting from two types

  17. Production and characterization of activated carbon from leather ...

    African Journals Online (AJOL)

    Powdered activated carbon (PAC) was prepared from leather buffing waste, sawdust and lignite by carbonization at temperatures between 500 – 800oC followed by steam activation. Experimental results reveal a general decrease in yield of carbon residue with increase in temperature of carbonization. Samples of lignite ...

  18. Great improvement on tetracycline removal using ZnO rod-activated carbon fiber composite prepared with a facile microwave method

    Energy Technology Data Exchange (ETDEWEB)

    Tran Thi, Viet Ha; Lee, Byeong-Kyu, E-mail: bklee@ulsan.ac.kr

    2017-02-15

    Highlights: • ZnO rod-ACF was prepared by a method involving a microwave within only 3 min. • ZnO rods (average diameter of 0.3–0.5 μm, length of 1.0–1.5 μm) were grown on ACF. • 99% of tetracycline was degraded and 90.7% TOC was removed within 1 h under UV light. • ZnO rod-ACF achieved high performances even after three cycles of uses. - Abstract: New composite materials of activated carbon fiber (ACF) coated with zinc oxide (ZnO) were obtained by applying a green, cost-effective and rapid synthetic route using a commercial microwave oven. ZnO rods with a uniform and stable structure and an average diameter of 0.3–0.5 μm and length of 1.0–1.5 μm were achieved after only 3-min microwave treatment. The properties of ZnO were efficiently transferred to ACF, such that the resulting material, termed ZnO rod-ACF, demonstrated a promising potential as an efficient photocatalyst and simultaneously as an adsorbent. Pharmaceutical tetracycline at a concentration of 40 mg/L was used to evaluate the organic pollutant removal capacity of the synthesized materials. At pH 8, ZnO rod-ACF exhibited excellent removal capacity (over 99%) and mineralization (90.7%) of tetracycline in aqueous solution within 1 h under UV irradiation. The stability of ZnO rod-ACF was maintained and the mineralization of tetracycline was also maintained at 81.35% after multiple usage cycles. The photodegradation pathways of tetracycline were proposed based on the identified reaction intermediates.

  19. Preparation and Application of Fluorescent Carbon Dots

    Directory of Open Access Journals (Sweden)

    Jun Zuo

    2015-01-01

    Full Text Available Fluorescent carbon dots (CDs are a novel type of fluorescent nanomaterials, which not only possess the specific quantum confinement effects of nanomaterials due to the small size of nanomaterials, but also have good biocompatibility and high fluorescence. Meanwhile, fluorescence CDs overcome the shortcomings of high toxicity of traditional nanomaterials. Moreover, the preparation procedure of fluorescent CDs is simple and easy. Therefore, fluorescent CDs have great potential applied in photocatalysis, biochemical sensing, bioimaging, drug delivery, and other related areas. In this paper, recent hot researches on fluorescent CDs are reviewed and some problems in the progress of fluorescent CDs are also summarized. At last, a future outlook in this direction is presented.

  20. Ultrasonic preparation of nano-nickel/activated carbon composite using spent electroless nickel plating bath and application in degradation of 2,6-dichlorophenol.

    Science.gov (United States)

    Su, Jingyu; Jin, Guanping; Li, Changyong; Zhu, Xiaohui; Dou, Yan; Li, Yong; Wang, Xin; Wang, Kunwei; Gu, Qianqian

    2014-11-01

    Ni was effectively recovered from spent electroless nickel (EN) plating baths by forming a nano-nickel coated activated carbon composite. With the aid of ultrasonication, melamine-formaldehyde-tetraoxalyl-ethylenediamine chelating resins were grafted on activated carbon (MFT/AC). PdCl2 sol was adsorbed on MFT/AC, which was then immersed in spent electroless nickel plating bath; then nano-nickel could be reduced by ascorbic acid to form a nano-nickel coating on the activated carbon composite (Ni/AC) in situ. The materials present were carefully examined by Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy, X-ray photoelectron spectroscopy and electrochemistry techniques. The resins were well distributed on the inside and outside surfaces of activated carbon with a size of 120 ± 30 nm in MFT/AC, and a great deal of nano-nickel particles were evenly deposited with a size of 3.8 ± 1.1 nm in Ni/MFT. Moreover, Ni/AC was successfully used as a catalyst for ultrasonic degradation of 2,6-dichlorophenol. Copyright © 2014. Published by Elsevier B.V.

  1. Novel preparation of carbon-TiO{sub 2} composites

    Energy Technology Data Exchange (ETDEWEB)

    Elizalde-González, María P., E-mail: maria.elizalde.uap.mx@gmail.com; García-Díaz, Esmeralda; Sabinas-Hernández, Sergio A.

    2013-12-15

    Highlights: • Glycerol and TiOSO{sub 4}·xH{sub 2}O produced a carbon-anatase precursor in a one-step sol–gel reaction. • Ultrasound irradiation led to the formation of crystalline TiO{sub 2} prior to thermal treatment. • Carbon and TiO{sub 2} nanocrystals developed larger specific surface in composites. • Large band gap (3.6 eV) in TiO{sub 2} was obtained. • Benzenesulfonic acid identified by LC–MS among decomposition reaction intermediates of the dye Acid Orange 7. -- Abstract: Carbon-TiO{sub 2} sulfated composites were obtained from TiOSO{sub 4}·xH{sub 2}O and glycerol as the TiO{sub 2} and carbon sources, respectively. The precursor xerogels were prepared in a one-step ultrasonic-assisted sol–gel reaction, followed by thermal treatment at 400 °C under a nitrogen atmosphere to produce carbon-TiO{sub 2} sulfated composites. XRD, micro-Raman, SEM, and TEM studies showed that the composites consisted of nanocrystalline clusters of TiO{sub 2} and carbon. Ultrasonication in glycerol promoted the crystallinity of the xerogel precursors prior to thermal treatment. X-ray powder diffraction and Raman spectroscopy studies confirmed that glycerol also facilitated the formation of small crystallites. The band gaps of carbon-TiO{sub 2} composites with two different carbon loadings were found to be 3.06 eV and 2.69 eV. By contrast, the band gap of TiO{sub 2} prepared by our method was 3.53 eV. Calcination of the precursors led to an unusual increase in the specific surface and porosity of the composites compared to TiO{sub 2}. The photocatalytic activities of the prepared composites were tested in a decomposition assay of Acid Orange 7. The reaction was monitored by UV–vis spectrophotometry and by LC-ESI-(Qq)-TOF-MS-DAD. Some intermediate species were identified by LC-ESI-QTOF-MS.

  2. Activated carbon preparation with pore nanosized from biomass precursors; Preparacao de carvoes ativados com poros de dimensoes nanometricas a partir de precursores de biomassa

    Energy Technology Data Exchange (ETDEWEB)

    Capobianco, Gino [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Fac. de Engenharia Mecanica. Dept. de Planejamento de Sistemas Energeticos; Coutinho, Aparecido dos Reis [Universidade Metodista de Piracicaba, SP (Brazil). Lab. de Materiais Carbonosos; Luengo, Carlos Alberto [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Inst. de Fisica Gleb Wataghin. Grupo Combustiveis Alternativos

    2004-07-01

    Here are reported preliminary tests using pinnus wood, mesocarpo of green coconut and macadamia shell. They are carbonized and later physically activated with CO{sub 2} or chemically with ZnCl{sub 2}. The resulting activated carbons (AC) are characterized with scanning electronic microscopy, the BET method for determination of the specific surface area-ASE, real density-DR, helium picnometry among others. The results indicate macadamia shell originates better AC, with average micropores in the range of 1,2-1,6 nm, apparent density of 1,08 g/cm{sup 3}, and ASE-BET 1400m{sup 2}/g. Then, these AC have the possibility to be applied in NG storage. (author)

  3. Preparation of Pt–Ru bimetallic catalyst supported on carbon ...

    Indian Academy of Sciences (India)

    Unknown

    Among the different strategies employed to synthesize the nanostruc- tured materials, template synthesis is an elegant app- roach. The template aided synthesis of ... In this communication, we report the use of polyphenyl acetylene as the carbon source to prepare carbon nano- tubes. Since it has a rich source of carbon and ...

  4. Dewatering Peat With Activated Carbon

    Science.gov (United States)

    Rohatgi, N. K.

    1984-01-01

    Proposed process produces enough gas and carbon to sustain itself. In proposed process peat slurry is dewatered to approximately 40 percent moisture content by mixing slurry with activated carbon and filtering with solid/liquid separation techniques.

  5. Production and characterization of granular activated carbon from activated sludge

    Directory of Open Access Journals (Sweden)

    Z. Al-Qodah

    2009-03-01

    Full Text Available In this study, activated sludge was used as a precursor to prepare activated carbon using sulfuric acid as a chemical activation agent. The effect of preparation conditions on the produced activated carbon characteristics as an adsorbent was investigated. The results indicate that the produced activated carbon has a highly porous structure and a specific surface area of 580 m²/g. The FT-IR analysis depicts the presence of a variety of functional groups which explain its improved adsorption behavior against pesticides. The XRD analysis reveals that the produced activated carbon has low content of inorganic constituents compared with the precursor. The adsorption isotherm data were fitted to three adsorption isotherm models and found to closely fit the BET model with R² equal 0.948 at pH 3, indicating a multilayer of pesticide adsorption. The maximum loading capacity of the produced activated carbon was 110 mg pesticides/g adsorbent and was obtained at this pH value. This maximum loading was found experimentally to steeply decrease as the solution pH increases. The obtained results show that activated sludge is a promising low cost precursor for the production of activated carbon.

  6. Effect of preparation method on the surface characteristics and activity of the Pd/OMS-2 catalysts for the oxidation of carbon monoxide, toluene, and ethyl acetate

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Lisha; Song, Yong; Fu, Zhidan [Key Laboratory of Beijing on Regional Air Pollution Control, Department of Environmental Science, College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124 (China); Ye, Qing, E-mail: yeqing@bjut.edu.cn [Key Laboratory of Beijing on Regional Air Pollution Control, Department of Environmental Science, College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124 (China); Cheng, Shuiyuan; Kang, Tianfang [Key Laboratory of Beijing on Regional Air Pollution Control, Department of Environmental Science, College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124 (China); Dai, Hongxing, E-mail: hxdai@bjut.edu.cn [Beijing Key Laboratory for Green Catalysis and Separation, Key Laboratory of Beijing on Regional Air Pollution Control, Department of Chemistry and Chemical Engineering, College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124 (China)

    2017-02-28

    Highlights: • The framework-structured of cryptomelane-type manganese oxide octahedral molecular sieve (OMS-2) has a 2 × 2 square tunnel. • Preparation route has an important impact on physicochemical property of the product. • Pd/OMS-2-DP via the deposition-precipitation route shows excellent catalytic activity. • Pd surface loading, surface atomic ratio of Mn ions, lattice oxygen mobility, oxygen vacancy, reducibility and acidity govern activity. - Abstract: The cryptomelane-type manganese oxide octahedral molecular sieve (OMS-2)-supported Pd (0.5 wt% Pd/OMS-2-DP, 0.5 wt% Pd/OMS-2-PI, and 0.5 wt% Pd/OMS-2-EX) catalysts were prepared by the deposition-precipitation, pre-incorporation, and ion-exchanging strategies, respectively. It is shown that the preparation method exerted an important effect on the physicochemical property of the sample. Among the OMS-2-supported Pd catalysts, 0.5 wt% Pd/OMS-2-DP possessed the highest surface (Mn{sup 2+} + Mn{sup 3+})/Mn{sup 4+} atomic ratio and the highest surface Pd loading and acid sites. The 0.5 wt% Pd/OMS-2 catalysts outperformed the Pd-free counterpart, among which 0.5 wt% Pd/OMS-2-DP presented the best catalytic activity (T{sub 50%} and T{sub 90%} were 25 and 55 °C for CO oxidation, 240 and 285 °C for toluene oxidation, and 160 and 200 °C for ethyl acetate oxidation, respectively). We believe that the high Pd surface loading, high surface atomic ratio of (Mn{sup 2+} + Mn{sup 3+})/Mn{sup 4+}, and good low-temperature reducibility, good oxygen mobility, and high acidity were responsible for the excellent performance of the 0.5 wt% Pd/OMS-2-DP catalyst.

  7. The Preparation of Flaky Layered Carbon by Using Layered Silicate Template

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Oh Yun [Yosu National University, Yeosu (Korea, Republic of); Park, Kyeong Won [Gyeongsang National University, Jinju (Korea, Republic of)

    2003-11-15

    Porous layered carbons with well-developed flake structure were successfully prepared by using layered silicate template. The gallery of layered silicate is composed of two-dimensional spaces with nano scale, which can have a role as nano reactor for chemicals introduced into the gallery. It confirmed that PFO, in this nano reactor, could be transformed easily to layered carbon or graphite structure by the heat treatment, allowing layered carbon-layered silicate nanocomposite (LC-LSN) piled carbon film or graphite sheet in layers of layered silicate. The removal of template from LC-LSN resulted in separated and well-developed flaky layered carbon or graphite with large surface area of 160-240 m{sup 2}/g, which was quite different from carbon black and activated carbon. In recent years, the preparation and application of nanostructure carbon materials such as carbon nanotube and nanoporous carbon has attracted increasing interests. We now report on the preparation of flaky layered carbon by using layered silicates as template. These layered carbons should be applicable potentially in technical field such as the electronics, catalytic and hydrogen-storage system. Layered silicates have exchangeable cations such as Na{sup +}, K{sup +}, Ca{sup 2+} and Mg{sup 2+} in the interlayer space.

  8. Preparation and Application of Fluorescent Carbon Dots

    National Research Council Canada - National Science Library

    Zuo, Jun; Jiang, Tao; Zhao, Xiaojing; Xiong, Xiaohong; Xiao, Saijin; Zhu, Zhiqiang

    2015-01-01

      Fluorescent carbon dots (CDs) are a novel type of fluorescent nanomaterials, which not only possess the specific quantum confinement effects of nanomaterials due to the small size of nanomaterials, but also have good...

  9. Preparation of array of long carbon nanotubes and fibers therefrom

    Energy Technology Data Exchange (ETDEWEB)

    Arendt, Paul N.; DePaula, Ramond F.; Zhu, Yuntian T.; Usov, Igor O.

    2015-11-19

    An array of carbon nanotubes is prepared by exposing a catalyst structure to a carbon nanotube precursor. Embodiment catalyst structures include one or more trenches, channels, or a combination of trenches and channels. A system for preparing the array includes a heated surface for heating the catalyst structure and a cooling portion that cools gas above the catalyst structure. The system heats the catalyst structure so that the interaction between the precursor and the catalyst structure results in the formation of an array of carbon nanotubes on the catalyst structure, and cools the gas near the catalyst structure and also cools any carbon nanotubes that form on the catalyst structure to prevent or at least minimize the formation of amorphous carbon. Arrays thus formed may be used for spinning fibers of carbon nanotubes.

  10. Removal of imidacloprid using activated carbon produced from ...

    African Journals Online (AJOL)

    In this study, Ricinodendron heudelotii (akpi) shells are used as precursor to prepare activated carbon via chemical activation using phosphoric acid. The characterization of the obtained activated carbon is performed using X-ray diffraction (XRD), Boehm titration method and adsorption of acetic acid. The results show that ...

  11. Preparation of Electrically Conductive Polystyrene/Carbon Nanofiber Nanocomposite Films

    Science.gov (United States)

    Sun, Luyi; O'Reilly, Jonathan Y.; Tien, Chi-Wei; Sue, Hung-Jue

    2008-01-01

    A simple and effective approach to prepare conductive polystyrene/carbon nanofiber (PS/CNF) nanocomposite films via a solution dispersion method is presented. Inexpensive CNF, which has a structure similar to multi-walled carbon nanotubes, is chosen as a nanofiller in this experiment to achieve conductivity in PS films. A good dispersion is…

  12. A new method of preparing single-walled carbon nanotubes

    Indian Academy of Sciences (India)

    A novel method of purification for single-walled carbon nanotubes, prepared by an arc-discharge method, is described. The method involves a combination of acid washing followed by high temperature hydrogen treatment to remove the metal nanoparticles and amorphous carbon present in the as-synthesized singlewalled ...

  13. CO2 adsorption at nitrogen-doped carbons prepared by K2CO3 activation of urea-modified coconut shell.

    Science.gov (United States)

    Yue, Limin; Xia, Qiongzhang; Wang, Liwei; Wang, Linlin; DaCosta, Herbert; Yang, Jie; Hu, Xin

    2018-02-01

    This article reports on the synthesis and characterization of porous nitrogen-doped carbons synthesized by carbonization of coconut shell followed by urea modification and K2CO3 activation. The as-synthesized samples were carefully characterized by various techniques. This series of samples demonstrate high CO2 uptake at 1bar, up to 3.71mmol/g at 25°C in addition to 5.12mmol/g at 0°C. Furthermore, these sorbents possess fast CO2 adsorption kinetics, stable reusability, moderate heat of CO2 adsorption, reasonable CO2/N2 selectivity, and high dynamic CO2 capture capacity under simulated flue gas conditions. It is found that, in addition to nitrogen content and narrow micropore volume, the pore size distribution of narrow micropore also plays a major role in determining the CO2 capture capacity under ambient condition. This work is intended to provide useful information and to inspire ways to develop new carbonaceous sorbents for removing CO2 from combustion flue gas. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Processes for preparing carbon fibers using gaseous sulfur trioxide

    Energy Technology Data Exchange (ETDEWEB)

    Barton, Bryan E.; Lysenko, Zenon; Bernius, Mark T.; Hukkanen, Eric J.

    2016-01-05

    Disclosed herein are processes for preparing carbonized polymers, such as carbon fibers, comprising: sulfonating a polymer with a sulfonating agent that comprises SO.sub.3 gas to form a sulfonated polymer; treating the sulfonated polymer with a heated solvent, wherein the temperature of said solvent is at least 95.degree. C.; and carbonizing the resulting product by heating it to a temperature of 500-3000.degree. C.

  15. Preparation and properties of carbon fibers based on lignin

    OpenAIRE

    Liu, Tengfei

    2017-01-01

    Abstract Lignin is one of the main components of plant fiber materials, and its stock in nature only inferior to cellulose. Lignin can be used as a carbon fiber materials owing to its high carbon content (usually 55% ~ 66%). Generally, lignin is a by-product of pulping process without recycling, which causes a big problem in environment protection and materials utilization. In this paper, formic acid lignin was extracted from black liquor, and nano-carbon fiber was prepared from formi...

  16. Method for the preparation of carbon fiber from polyolefin fiber precursor, and carbon fibers made thereby

    Science.gov (United States)

    Naskar, Amit Kumar; Hunt, Marcus Andrew; Saito, Tomonori

    2015-08-04

    Methods for the preparation of carbon fiber from polyolefin fiber precursor, wherein the polyolefin fiber precursor is partially sulfonated and then carbonized to produce carbon fiber. Methods for producing hollow carbon fibers, wherein the hollow core is circular- or complex-shaped, are also described. Methods for producing carbon fibers possessing a circular- or complex-shaped outer surface, which may be solid or hollow, are also described.

  17. (PSLW) Activated Carbon

    African Journals Online (AJOL)

    ADOWIE PERE

    2017-12-02

    Dec 2, 2017 ... ABSTRACT: Silver-impregnated carbon (SIC) and its precursor (un-impregnated) derived from an easily available low cost plant material Prosopis spicigera L. wood (PSLW) carbon was investigated for their ability to remove arsenic from aqueous solutions in batch and column experiments. Arsenic uptake ...

  18. Preparation of arrays of long carbon nanotubes using catalyst structure

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Yuntian T.; Arendt, Paul; Li, Qingwen; Zhang, Xiefie

    2016-03-22

    A structure for preparing an substantially aligned array of carbon nanotubes include a substrate having a first side and a second side, a buffer layer on the first side of the substrate, a catalyst on the buffer layer, and a plurality of channels through the structure for allowing a gaseous carbon source to enter the substrate at the second side and flow through the structure to the catalyst. After preparing the array, a fiber of carbon nanotubes may be spun from the array. Prior to spinning, the array can be immersed in a polymer solution. After spinning, the polymer can be cured.

  19. Effect of preparation method on the surface characteristics and activity of the Pd/OMS-2 catalysts for the oxidation of carbon monoxide, toluene, and ethyl acetate

    Science.gov (United States)

    Liu, Lisha; Song, Yong; Fu, Zhidan; Ye, Qing; Cheng, Shuiyuan; Kang, Tianfang; Dai, Hongxing

    2017-02-01

    The cryptomelane-type manganese oxide octahedral molecular sieve (OMS-2)-supported Pd (0.5 wt% Pd/OMS-2-DP, 0.5 wt% Pd/OMS-2-PI, and 0.5 wt% Pd/OMS-2-EX) catalysts were prepared by the deposition-precipitation, pre-incorporation, and ion-exchanging strategies, respectively. It is shown that the preparation method exerted an important effect on the physicochemical property of the sample. Among the OMS-2-supported Pd catalysts, 0.5 wt% Pd/OMS-2-DP possessed the highest surface (Mn2+ + Mn3+)/Mn4+ atomic ratio and the highest surface Pd loading and acid sites. The 0.5 wt% Pd/OMS-2 catalysts outperformed the Pd-free counterpart, among which 0.5 wt% Pd/OMS-2-DP presented the best catalytic activity (T50% and T90% were 25 and 55 °C for CO oxidation, 240 and 285 °C for toluene oxidation, and 160 and 200 °C for ethyl acetate oxidation, respectively). We believe that the high Pd surface loading, high surface atomic ratio of (Mn2+ + Mn3+)/Mn4+, and good low-temperature reducibility, good oxygen mobility, and high acidity were responsible for the excellent performance of the 0.5 wt% Pd/OMS-2-DP catalyst.

  20. [Preparation of nano zero-valent iron/Sargassum horneri based activated carbon for removal of Cr (VI) from aqueous solution].

    Science.gov (United States)

    Zeng, Gan-Ning; Wu, Xiao; Zheng, Lin; Wu, Xi; Tu, Mei-Ling; Wang, Tie-Gan; Ai, Ning

    2015-02-01

    Nanoscale zero-valent iron supported on Sargassum horneri activated carbon (NZVI/SAC) was synthesized by zinc chloride activation and incipient wetness method, and characterized with X-ray diffraction (XRD), Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). XRD confirmed the existence of nano zero-valent iron, and SEM revealed that the material consisted of mainly 30-150 nm spherical particles aggregated into chains of individual units. The valence state of iron conformed with the nuclear-shell model. The effects of NZVI loading on AC, pH and the initial concentration of Cr(VI) on the removal of Cr(VI) were investigated. The final Cr(VI) removal percentage was up to 100% under the following conditions: 30 degrees C, pH = 2, NZVI/SAC dosage of 2 g x L(-1) and the amounts of NZVI loaded on SAC of 30%. And the equilibrium time was 10 minutes. These results showed that NZVI/SAC could be potentially applied for removal of high concentration Cr(VI). By analyzing the chemical change of NZVI/ SAC, we demonstrated that Cr(VI) was mainly reduced to insoluble Cr (III) compound in the reaction when pH was less than 4, and adsorbed by NZVI and SAC when pH was over 4.

  1. Production of activated carbon from a new precursor: Molasses

    Science.gov (United States)

    Legrouri, K.; Ezzine, M.; Ichcho, S.; Hannache, H.; Denoyel, R.; Pailler, R.; Naslain, R.

    2005-03-01

    Activated carbon has been prepared from molasses, a natural precursor of vegetable origin resulting from the sugar industry in Morocco. The preparation of the activated carbon from the molasses has been carried out by impregnation of the precursor with sulfuric acid, followed by carbonization. The adsorption capacity, the BET surface area, and the pore volume of the activated carbon were determined. The micropore volume was assessed by Dubinin- Radushkevich (DR) equation. The activated materials are mainly microporous and show the type I isotherm of the Brunauer classification for nitrogen adsorption. The activation in steam yielded a carbon that contains both micropores and supermicropores. Analysis of the nitrogen isotherm by BET and DR methods established that most of obtained carbons are highly microporous, with high surface areas (≥ 1200 m2/g) and very low mesoporosity.

  2. Phenol adsorption by activated carbon produced from spent coffee grounds.

    Science.gov (United States)

    Castro, Cínthia S; Abreu, Anelise L; Silva, Carmen L T; Guerreiro, Mário C

    2011-01-01

    The present work highlights the preparation of activated carbons (ACs) using spent coffee grounds, an agricultural residue, as carbon precursor and two different activating agents: water vapor (ACW) and K(2)CO(3) (ACK). These ACs presented the microporous nature and high surface area (620-950 m(2) g(-1)). The carbons, as well as a commercial activated carbon (CAC) used as reference, were evaluated as phenol adsorbent showing high adsorption capacity (≈150 mg g(-1)). The investigation of the pH solution in the phenol adsorption was also performed. The different activating agents led to AC with distinct morphological properties, surface area and chemical composition, although similar phenol adsorption capacity was verified for both prepared carbons. The production of activated carbons from spent coffee grounds resulted in promising adsorbents for phenol removal while giving a noble destination to the residue.

  3. Preparation of porous carbon sphere from waste sugar solution for electric double-layer capacitor

    Science.gov (United States)

    Hao, Zhi-Qiang; Cao, Jing-Pei; Wu, Yan; Zhao, Xiao-Yan; Zhuang, Qi-Qi; Wang, Xing-Yong; Wei, Xian-Yong

    2017-09-01

    Waste sugar solution (WSS), which contains abundant 2-keto-L-gulonic acid, is harmful to the environment if discharged directly. For value-added utilization of the waste resource, a novel process is developed for preparation of porous carbon spheres by hydrothermal carbonization (HTC) of WSS followed by KOH activation. Additionally, the possible preparation mechanism of carbon spheres is proposed. The effects of hydrothermal and activation parameters on the properties of the carbon sphere are also investigated. The carbon sphere is applied to electric double-layer capacitor and its electrochemical performance is studied. These results show that the carbon sphere obtained by HTC at 180 °C for 12 h with the WSS/deionized water volume ratio of 2/3 possess the highest specific capacitance under identical activation conditions. The specific capacitance of the carbon spheres can reach 296.1 F g-1 at a current density of 40 mA g-1. Besides, excellent cycle life and good capacitance retention (89.6%) are observed at 1.5 A g-1 after 5000 cycles. This study not only provides a facile and potential method for the WSS treatment, but also achieves the high value-added recycling of WSS for the preparation of porous carbon spheres with superior electrochemical properties.

  4. 2,4-D adsorption to biochars: effect of preparation conditions on equilibrium adsorption capacity and comparison with commercial activated carbon literature data.

    Science.gov (United States)

    Kearns, J P; Wellborn, L S; Summers, R S; Knappe, D R U

    2014-10-01

    Batch isotherm experiments were conducted with chars to study adsorption of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D). Chars generated from corncobs, bamboo and wood chips in a laboratory pyrolyzer at 400-700 °C were compared with traditional kiln charcoals collected from villages in S/SE Asia and with activated carbons (ACs). 2,4-D uptake by laboratory chars obtained from bamboo and wood chips after 14 h of pyrolysis at 700 °C, from wood chips after 96 h of pyrolysis at 600 °C, and one of the field-collected chars (basudha) was comparable to ACs. H:C and O:C ratios declined with pyrolysis temperature and duration while surface area increased to >500 m(2)/g. Increasing pyrolysis intensity by increasing temperature and/or duration of heating was found to positively influence adsorption capacity yield (mg(2,4-D/g(feedstock))) over the range of conditions studied. Economic analysis showed that high temperature chars can be a cost-effective alternative to ACs for water treatment applications. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Preparation and characterization of PdO nanoparticles on trivalent metal (B, Al and Ga) substituted MCM-41: excellent catalytic activity in supercritical carbon dioxide.

    Science.gov (United States)

    Chatterjee, M; Ishizaka, T; Kawanami, H

    2014-04-15

    Palladium oxide (PdO) nanoparticles supported on B, Al and Ga modified mesoporous MCM-41with different Si/M ratios (where, M=B, Al or Ga) varied from 100 to 5 was synthesized in one-pot. Developed materials were characterized by several techniques such as XRD, TEM, UV-Vis, XPS and TG-DTA. A highly ordered structure was revealed by XRD for all the support materials depending on Si/M ratio. TEM analysis evidenced the presence of spherical PdO particles. Interestingly, the particle sizes correlated well with Si/M ratio as well as the nature of M. Spectroscopic characterization of calcined materials suggested the presence of Pd(2+), whereas XPS confirmed the existence of Pd(2+) in PdO form. The catalytic activity of resultant materials was investigated by the chemoselective hydrogenation of chloronitrobenzene in supercritical carbon dioxide. All the materials exhibit excellent conversion of chloronitrobenzene and selectivity to chloroaniline within the reaction time of 50 min. at 35 °C. Substitution of Si by trivalent metal cation improved the catalytic performance of B and Ga containing catalysts. Among the three catalysts, superior catalytic activity was observed for Pd/B-MCM-41 with highest conversion (100%) and selectivity to chloroaniline (100%) and thus, followed the reactivity order of PdO/B>PdO/Ga>PdO/Al. Considering o-, m- and p-chloronitrobenzene, for all the materials conversion followed the order of p->m->o-, whereas selectivity to chloroaniline for all three isomers were strongly influenced by the trivalent metal ion in the support material. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Production and Characterization of Activated Carbon Fiber from Textile PAN Fiber

    OpenAIRE

    Amaral Junior,Miguel Angelo do; Matsushima,Jorge Tadao; Rezende,Mirabel Cerqueira; Gonçalves,Emerson Sarmento; Marcuzzo,Jossano Saldanha; Baldan,Maurício Ribeiro

    2017-01-01

    ABSTRACT: This paper presents the preparation and characterization of carbon fiber felt and activated carbon fiber felt from textile polyacrylonitrile fiber. Carbon fibers are usually related to aircraft manufacturing or high mechanical purposes. Activated carbon fibers are known as excellent adsorbent materials. Despite all advantages, carbon fiber and activated carbon fiber are expensive materials because of their raw material cost. On the other hand, in this study, carbon fiber felt and ac...

  7. Preparation of porous carbon films from polyacrylonitrile by proton irradiation and carbonization

    Science.gov (United States)

    Lee, Hwa Su; Baek, Ga Young; Hwang, In-Tae; Jung, Chan-Hee; Choi, Jae-Hak

    2017-12-01

    Porous carbon films (PCFs) are widely used in various application fields, such as separation and water desalination as well as energy storage and conversion. In this study, PCFs were prepared from polyacrylonitrile (PAN) by proton irradiation and carbonization. Porous PAN films were prepared by a non-solvent-induced phase separation process. The porous PAN films were irradiated with proton ions, and then carbonized in a tube furnace at various fluences under an inert atmosphere. It was found that pore structures were well maintained during proton irradiation and high-temperature carbonization processes. The Raman and XRD results showed that pseudo-graphitic structures were formed by the carbonization of proton irradiated porous PAN films. The electrical conductivity of the prepared PCFs increased with an increasing carbonization temperature due to the formation of more graphitic structures at a higher temperature.

  8. Preparation of carbon-free TEM microgrids by metal sputtering.

    Science.gov (United States)

    Janbroers, S; de Kruijff, T R; Xu, Q; Kooyman, P J; Zandbergen, H W

    2009-08-01

    A new method for preparing carbon-free, temperature-stable Transmission Electron Microscope (TEM) grids is presented. An 80% Au/20% Pd metal film is deposited onto a 'holey' microgrid carbon supported on standard mixed-mesh Au TEM grids. Subsequently, the carbon film is selectively removed using plasma cleaning. In this way, an all-metal TEM film is made containing the 'same' microgrid as the original carbon film. Although electron transparency of the foil is reduced significantly, the open areas for TEM inspection of material over these areas are maintained. The metal foil can be prepared with various thicknesses and ensures good electrical conductivity. The new Au/Pd grids are stable to at least 775K under vacuum conditions.

  9. Preparation of supported electrocatalyst comprising multiwalled carbon nanotubes

    Science.gov (United States)

    Wu, Gang; Zelenay, Piotr

    2013-08-27

    A process for preparing a durable non-precious metal oxygen reduction electrocatalyst involves heat treatment of a ball-milled mixture of polyaniline and multiwalled carbon nanotubes in the presence of a Fe species. The catalyst is more durable than catalysts that use carbon black supports. Performance degradation was minimal or absent after 500 hours of operation at constant cell voltage of 0.40 V.

  10. Numerical analysis of the influence of the impregnation ratio on the microporous structure formation of activated carbons, prepared by chemical activation of waste biomass with phosphoric(V) acid

    Science.gov (United States)

    Kwiatkowski, Mirosław; Kalderis, Dimitrios; Diamadopoulos, Evan

    2017-06-01

    This paper presents the results of the application of new mathematical adsorption models with the unique numerical fast multivariate identification procedure as the tool for analysing the influence of the impregnation ratio i.e. activator to the raw material mass ratio on the microporous structure development of the activated carbons, obtained from sugarcane bagasse and rice husk by chemical activation with phosphoric(V) acid.

  11. Influence of different carbon monolith preparation parameters on pesticide adsorption

    Directory of Open Access Journals (Sweden)

    Vukčević Marija

    2013-01-01

    Full Text Available The capacity of carbon monolith for pesticide removal from water, and the mechanism of pesticide interaction with carbon surface were examined. Different carbon monolith samples were obtained by varying the carbonization and activation parameters. In order to examine the role of surface oxygen groups in pesticide adsorption, carbon monolith surface was functionalized by chemical treatment in HNO3, H2O2 and KOH. The surface properties of the obtained samples were investigated by BET surface area, pore size distribution and temperature-programmed desorption. Adsorption of pesticides from aqueous solution onto activated carbon monolith samples was studied by using five pesticides belonging to different chemical groups (acetamiprid, dimethoate, nicosulfuron, carbofuran and atrazine. Presented results show that higher temperature of carbonization and the amount of activating agent allow obtaining microporous carbon monolith with higher amount of surface functional groups. Adsorption properties of the activated carbon monolith were more readily affected by the amount of the surface functional groups than by specific surface area. Results obtained by carbon monolith functionalisation showed that π-π interactions were the main force for adsorption of pesticides with aromatic structure, while acidic groups play an important role in adsorption of pesticides with no aromatic ring in the chemical structure.

  12. High activity carbon sorbents for mercury capture

    Directory of Open Access Journals (Sweden)

    Stavropoulos George G.

    2006-01-01

    Full Text Available High efficiency activated carbons have been prepared for removing mercury from gas streams. Starting materials used were petroleum coke, lignite, charcoal and olive seed waste, and were chemically activated with KOH. Produced adsorbents were primarily characterized for their porosity by N2 adsorption at 77 K. Their mercury retention capacity was characterized based on the breakthrough curves. Compared with typical commercial carbons, they have exhibited considerably enhanced mercury adsorption capacity. An attempt has been made to correlate mercury entrapment and pore structure. It has been shown that physical surface area is increased during activation in contrast to the mercury adsorption capacity that initially increases and tends to decrease at latter stages. Desorption of active sites may be responsible for this behavior.

  13. Preparation and Electrochemical Properties of Silver Doped Hollow Carbon Nanofibers

    Directory of Open Access Journals (Sweden)

    LI Fu

    2016-11-01

    Full Text Available Silver doped PAN-based hollow carbon nanofibers were prepared combining co-electrospinning with in situ reduction technique subsequently heat treatment to improve the electrochemical performances of carbon based supercapacitor electrodes. The morphology, structure and electrochemical performances of the resulted nanofiber were studied. The results show that the silver nanoparticles can be doped on the surface of hollow carbon nanofibers and the addition of silver favors the improvement of the electrochemical performances, exhibiting the enhanced reversibility of electrode reaction and the capacitance and the reduced charge transfer impedance.

  14. Preparation and Characterization of a Calcium Carbonate Aerogel

    Directory of Open Access Journals (Sweden)

    Johann Plank

    2009-01-01

    Full Text Available We report on a facile method for the preparation of a calcium carbonate aerogel consisting of aggregated secondary vaterite particles with an approximate average diameter of 50 nm. It was synthesized via a sol-gel process by reacting calcium oxide with carbon dioxide in methanol and subsequent supercritical drying of the alcogel with carbon dioxide. The resulting monolith was opaque, brittle and had overall dimensions of 6×2×1 cm. It was characterized by X-ray powder diffraction, nitrogen adsorption method (BET, and scanning electron microscopy.

  15. Use of sawdust Eucalyptus sp. in the preparation of activated carbons Utilização de serragem de Eucalyptus sp. na preparação de carvões ativados

    Directory of Open Access Journals (Sweden)

    Gabriela Martucci Couto

    2012-02-01

    Full Text Available Wood sawdust is a solid residue, generated in the timber industry, which is of no profitable use and can cause serious environmental problems if disposed inadequately. The aim of this study was to use the eucalyptus sawdust in the preparation of activated carbons AC and test them as adsorbents of methylene blue (MB and phenol, representative pollutants from aqueous effluents of various industries. The eucalyptus sawdust was characterized by instrumental analysis such as elementary analysis (CHNS-O, thermogravimetric analysis (TGA, infrared spectroscopy (FTIR and scanning electron microscopy (SEM. The activated carbons were prepared by physical activation with carbon dioxide AC_CO2, (10º C min-1, 850º C, 1h and by chemical activation with potassium carbonate AC_K2CO3 (10º C min-1, 850º C, 3h. The AC_CO2 and AC_K2CO3 were characterized by CHN-O, TGA, FTIR, N2 adsorption/desorption (BET to evaluate the specific surface area and SEM. The resulting activated carbons were tested for their ability to adsorb MB and phenol in water. The activated carbons produced in this work were predominantly microporous and showed specific surface area of about 535 m² g-1. The AC_K2CO3 was more effective in the adsorption of MB (81 mg g-1 and phenol (330 mg g-1 than AC_CO2 (32 mg g-1 and 172 mg g-1, respectively, for MB and phenol.A serragem é um resíduo sólido, gerado na indústria madeireira, que não tem uso rentável e pode causar sérios problemas ambientais quando disposta inadequadamente. Neste estudo, objetivou-se utilizar a serragem de eucalipto na preparação de carvões ativados (AC e testá-los como adsorventes do corante azul de metileno (MB e fenol; moléculas que representam poluentes de efluentes industriais. A serragem de eucalipto foi caracterizada por análises instrumentais, tais como: análise elementar (CHNS-O, análise termogravimétrica (TGA, espectroscopia na região do infravermelho (FTIR e microscopia eletrônica de varredura (SEM

  16. Preparation of porous carbon particle with shell/core structure

    Directory of Open Access Journals (Sweden)

    2007-05-01

    Full Text Available Porous carbon particles with a shell/core structure have been prepared successfully by controlled precipitation of the polymer from droplets of oil-in-water emulsion, followed by curing and carbonization. The droplets of the oil phase are composed of phenolic resin (PFR, a good solvent (ethyl acetate and porogen (Poly(methyl methacrylate, PMMA. The microstructure was characterized in detail by scanning electron microscopy (SEM, transmission electron microscopy (TEM, nitrogen adsorption, and thermo gravimetric analysis (TGA. The obtained carbon particles have a capsular structure with a microporous carbon shell and a mesoporous carbon core. The BET surface area and porous volume are calculated to be 499 m2g-1 and 0.56 cm3g-1, respectively. The effects of the amount of porogen (PMMA, co-solvent (acetone and surfactant on the resultant structure were studied in detail.

  17. Carbon molecular sieve membranes prepared from porous fiber precursor

    NARCIS (Netherlands)

    Barsema, J.N.; van der Vegt, N.F.A.; Koops, G.H.; Wessling, Matthias

    2002-01-01

    Carbon molecular sieve (CMS) membranes are usually prepared from dense polymeric precursors that already show intrinsic gas separation properties. The rationale behind this approach is that the occurrence of any kind of initial porosity will deteriorate the final CMS performance. We will show that

  18. Morphology of carbon nanotubes prepared via chemical vapour ...

    Indian Academy of Sciences (India)

    2015-11-27

    Nov 27, 2015 ... Small angle neutron scattering (SANS) has been utilized to study the morphology of the multi-walled carbon nanotubes prepared by chemical vapour deposition of acetylene. The effects of various synthesis parameters like temperature, catalyst concentration and catalyst support on the size distribution of ...

  19. Morphology of carbon nanotubes prepared via chemical vapour ...

    Indian Academy of Sciences (India)

    Morphology of carbon nanotubes prepared via chemical vapour deposition technique using acetylene: A small angle neutron scattering investigation. D SEN1,∗, K DASGUPTA2, J BAHADUR1, S MAZUMDER1 and. D SATHIYAMOORTHY2. 1Solid State Physics; 2Powder Metallurgy Division, Bhabha Atomic Research ...

  20. Preparation of CN /Carbon Nanotube Intramolecular Junctions by ...

    African Journals Online (AJOL)

    NICO

    and 1(b) show the TEM images of the pure CNTs and CNx. Under these experimental conditions, the prepared CNTs are all multi-walled, i.e. MWCNTs. These MWCNTs demonstrate a typical tubular structure with hollow cores. The grown CNx have obvious bamboo-like morphology with transverse carbon bridges forming a ...

  1. Application of microcapsulation technology to the preparation of carbon foam

    Directory of Open Access Journals (Sweden)

    Ke-zhi Li, Zhen-hai Shi, He-jun Li, Zhuo Tian and Chuang Wang

    2008-01-01

    Full Text Available Microcapsules were prepared by in situ polymerization and microcapsulation. Tetraethyl orthosilicate was used as the core material and phenolic resin was used as the wall material in an emulsion system of polyacrylic and tetraethyl orthosilicate. The obtained microcapsules were slowly heated such that the core material was released by evaporation, leaving hollow-core spheres. The spheres were mixed with a phenolic resin-derived binder and molded to obtain a carbon foam precursor, which was carbonized at 1100 °C under the protection of N2 gas and graphitized at 2300 °C under the protection of Ar gas. Thus, the carbon foam of hollow closed-shelled microspheres with a graphitic structure was prepared. The properties and structure of this foam were discussed.

  2. Application of microcapsulation technology to the preparation of carbon foam.

    Science.gov (United States)

    Li, Ke-Zhi; Shi, Zhen-Hai; Li, He-Jun; Tian, Zhuo; Wang, Chuang

    2008-04-01

    Microcapsules were prepared by in situ polymerization and microcapsulation. Tetraethyl orthosilicate was used as the core material and phenolic resin was used as the wall material in an emulsion system of polyacrylic and tetraethyl orthosilicate. The obtained microcapsules were slowly heated such that the core material was released by evaporation, leaving hollow-core spheres. The spheres were mixed with a phenolic resin-derived binder and molded to obtain a carbon foam precursor, which was carbonized at 1100 °C under the protection of N 2 gas and graphitized at 2300 °C under the protection of Ar gas. Thus, the carbon foam of hollow closed-shelled microspheres with a graphitic structure was prepared. The properties and structure of this foam were discussed.

  3. Application of microcapsulation technology to the preparation of carbon foam

    Energy Technology Data Exchange (ETDEWEB)

    Li Kezhi; Shi Zhenhai; Li Hejun; Tian Zhuo; Wang Chuang [C/C Composites Technology Research Center, Northwestern Polytechnical University, Xi' an 710072 (China)], E-mail: likezhi@nwpu.edu.cn

    2008-04-15

    Microcapsules were prepared by in situ polymerization and microcapsulation. Tetraethyl orthosilicate was used as the core material and phenolic resin was used as the wall material in an emulsion system of polyacrylic and tetraethyl orthosilicate. The obtained microcapsules were slowly heated such that the core material was released by evaporation, leaving hollow-core spheres. The spheres were mixed with a phenolic resin-derived binder and molded to obtain a carbon foam precursor, which was carbonized at 1100 deg. C under the protection of N{sub 2} gas and graphitized at 2300 deg. C under the protection of Ar gas. Thus, the carbon foam of hollow closed-shelled microspheres with a graphitic structure was prepared. The properties and structure of this foam were discussed.

  4. Preparation of carbon nanoparticles and carbon nitride from high nitrogen compound

    Energy Technology Data Exchange (ETDEWEB)

    Huynh, My Hang V [Los Alamos, NM; Hiskey, Michael A [Los Alamos, NM

    2009-09-01

    The high-nitrogen compound 3,6-di(azido)-1,2,4,5-tetrazine (DiAT) was synthesized by a relatively simple method and used as a precursor for the preparation of carbon nanospheres and nanopolygons, and nitrogen-rich carbon nitrides.

  5. Calcium carbonate phase transformations during the carbonation reaction of calcium heavy alkylbenzene sulfonate overbased nanodetergents preparation.

    Science.gov (United States)

    Chen, Zhaocong; Xiao, Shan; Chen, Feng; Chen, Dongzhong; Fang, Jianglin; Zhao, Min

    2011-07-01

    The preparation and application of overbased nanodetergents with excess alkaline calcium carbonate is a good example of nanotechnology in practice. The phase transformation of calcium carbonate is of extensive concern since CaCO(3) serves both as an important industrial filling material and as the most abundant biomineral in nature. Industrially valuable overbased nanodetergents have been prepared based on calcium salts of heavy alkylbenzene sulfonate by a one-step process under ambient pressure, the carbonation reaction has been monitored by the instantaneous temperature changes and total base number (TBN). A number of analytical techniques such as TGA, DLS, SLS, TEM, FTIR, and XRD have been utilized to explore the carbonation reaction process and phase transformation mechanism of calcium carbonate. An enhanced understanding on the phase transformation of calcium carbonate involved in calcium sulfonate nanodetergents has been achieved and it has been unambiguously demonstrated that amorphous calcium carbonate (ACC) transforms into the vaterite polymorph rather than calcite, which would be of crucial importance for the preparation and quality control of lubricant additives and greases. Our results also show that a certain amount of residual Ca(OH)(2) prevents the phase transformation from ACC to crystalline polymorphs. Moreover, a vaterite nanodetergent has been prepared for the first time with low viscosity, high base number, and uniform particle size, nevertheless a notable improvement on its thermal stability is required for potential applications. Copyright © 2011 Elsevier Inc. All rights reserved.

  6. Obtenção e caracterização de carbono ativado a partir de resíduos provenientes de bandas de rodagem Preparation and characterization of activated carbons from thread of tire waste

    Directory of Open Access Journals (Sweden)

    Irene T. S. Garcia

    2007-12-01

    Full Text Available Neste trabalho foi investigada a preparação de carbonos ativados através da pirólise de composições elastoméricas provenientes de resíduos de bandas de rodagem de pneus de automóveis. O material foi processado nas temperaturas de 500, 620 e 700 °C, em atmosfera de N2, utilizando-se o hidróxido de potássio como agente ativador. Os produtos resultantes foram caracterizados pela fisisorção de N2 a 77 K, através de isotermas de Brunauer, Emmet e Teller e por microscopia eletrônica de varredura. Esses carbonos ativados apresentam estruturas típicas de sólidos mesoporosos e a temperatura de pirólise tem grande influência na área específica e distribuição de volume de poros. O carbono ativado obtido a 700 °C apresentou maior área específica e estrutura porosa compacta. Esse material apresenta melhor desempenho frente à adsorção de azul de metileno, removendo até 1,0 x 10-1 g de corante por grama de carbono utilizado, em tempos inferiores a 300 s.In this work, the preparation of activated carbons through the pyrolysis of elastomers, arising from car threads of tire waste, was investigated. The material was processed at 500, 620 and 700 °C, under N2 atmosphere, by using potassium hydroxide as activating agent. The resulting products were characterized by physisorption of N2 at 77 K, through Brunauer, Emmet and Teller isotherms, and scanning electron microscopy. The carbons obtained display a characteristic structure of mesoporous materials and the pyrolysis temperature has strong influence on the specific area and porous volume distribution. The activated carbon obtained at 700 °C has high specific area and compact structure. It exhibited high performance for adsorption of methylene blue solution, removing 1.1 x 10-1 g of the dye per gram of carbon in less than 300 s.

  7. Bioactive carbon-PEEK composites prepared by chemical surface treatment.

    Science.gov (United States)

    Miyazaki, Toshiki; Matsunami, Chisato; Shirosaki, Yuki

    2017-01-01

    Polyetheretherketone (PEEK) has attracted much attention as an artificial intervertebral spacer for spinal reconstruction. Furthermore, PEEK plastic reinforced with carbon fiber has twice the bending strength of pure PEEK. However, the PEEK-based materials do not show ability for direct bone bonding, i.e., bioactivity. Although several trials have been conducted for enabling PEEK with bioactivity, few studies have reported on bioactive surface modification of carbon-PEEK composites. In the present study, we attempted the preparation of bioactive carbon-PEEK composites by chemical treatments with H2SO4 and CaCl2. Bioactivity was evaluated by in vitro apatite formation in simulated body fluid (SBF). The apatite formation on the carbon-PEEK composite was compared with that of pure PEEK. Both pure PEEK and carbon-PEEK composite formed the apatite in SBF when they were treated with H2SO4 and CaCl2; the latter showed higher apatite-forming ability than the former. It is conjectured that many functional groups able to induce the apatite nucleation, such as sulfo and carboxyl groups, are incorporated into the dispersed carbon phase in the carbon-PEEK composites. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Preparation of porous carbon nanofibers derived from PBI/PLLA for supercapacitor electrodes

    Science.gov (United States)

    Jung, Kyung-Hye; Ferraris, John P.

    2016-10-01

    Porous carbon nanofibers were prepared by electrospinning blend solutions of polybenzimidazole/poly-L-lactic acid (PBI/PLLA) and carbonization. During thermal treatment, PLLA was decomposed, resulting in the creation of pores in the carbon nanofibers. From SEM images, it is shown that carbon nanofibers had diameters in the range of 100-200 nm. The conversion of PBI to carbon was confirmed by Raman spectroscopy, and the surface area and pore volume of carbon nanofibers were determined using nitrogen adsorption/desorption analyses. To investigate electrochemical performances, coin-type cells were assembled using free-standing carbon nanofiber electrodes and ionic liquid electrolyte. cyclic voltammetry studies show that the PBI/PLLA-derived porous carbon nanofiber electrodes have higher capacitance due to lower electrochemical impedance compared to carbon nanofiber electrode from PBI only. These porous carbon nanofibers were activated using ammonia for further porosity improvement and annealed to remove the surface functional groups to better match the polarity of electrode and electrolyte. Ragone plots, correlating energy density with power density calculated from galvanostatic charge-discharge curves, reveal that activation/annealing further improves energy and power densities.

  9. Activated Carbon Textile via Chemistry of Metal Extraction for Supercapacitors.

    Science.gov (United States)

    Lam, Do Van; Jo, Kyungmin; Kim, Chang-Hyun; Kim, Jae-Hyun; Lee, Hak-Joo; Lee, Seung-Mo

    2016-12-27

    Carbothermic reduction in the chemistry of metal extraction (MO(s) + C(s) → M(s) + CO(g)) using carbon as a sacrificial agent has been used to smelt metals from diverse oxide ores since ancient times. Here, we paid attention to another aspect of the carbothermic reduction to prepare an activated carbon textile for high-rate-performance supercapacitors. On the basis of thermodynamic reducibility of metal oxides reported by Ellingham, we employed not carbon, but metal oxide as a sacrificial agent in order to prepare an activated carbon textile. We conformally coated ZnO on a bare cotton textile using atomic layer deposition, followed by pyrolysis at high temperature (C(s) + ZnO(s) → C'(s) + Zn(g) + CO(g)). We figured out that it leads to concurrent carbonization and activation in a chemical as well as mechanical way. Particularly, the combined effects of mechanical buckling and fracture that occurred between ZnO and cotton turned out to play an important role in carbonizing and activating the cotton textile, thereby significantly increasing surface area (nearly 10 times) compared with the cotton textile prepared without ZnO. The carbon textiles prepared by carbothermic reduction showed impressive combination properties of high power and energy densities (over 20-fold increase) together with high cyclic stability.

  10. Preparation of Ceramic-Bonded Carbon Block for Blast Furnace

    Science.gov (United States)

    Li, Yiwei; Li, Yawei; Sang, Shaobai; Chen, Xilai; Zhao, Lei; Li, Yuanbing; Li, Shujing

    2014-01-01

    Traditional carbon blocks for blast furnaces are mainly produced with electrically calcined anthracite owing to its good hot metal corrosion resistance. However, this kind of material shows low thermal conductivity and does not meet the demands for cooling of the hearth and the bottom of blast furnaces. In this article, a new kind of a high-performance carbon block has been prepared via ceramic-bonded carbon (CBC) technology in a coke bed at 1673 K (1400 °C) using artificial graphite aggregate, alumina, metallic aluminum, and silicon powders as starting materials. The results showed that artificial graphite aggregates were strongly bonded by the three-dimensional network of ceramic phases in carbon blocks. In this case, the good resistance of the CBC blocks against erosion/corrosion by the hot metal is provided by the ceramic matrix and the high thermal conductivity by the graphite aggregates. The microstructure of this carbon block resembles that of CBC composites with a mean pore size of less than 0.1 μm, and up to 90 pct of the porosity shows a pore size <1 μm. Its thermal conductivity is higher than 30 W · m-1 · K-1 [293 K (20 °C)]. Meanwhile, its hot metal corrosion resistance is better than that of traditional carbon blocks.

  11. Application of microcapsulation technology to the preparation of carbon foam

    OpenAIRE

    Li, Ke-zhi; Shi, Zhen-hai; Li, He-jun; Tian, Zhuo; Wang, Chuang

    2008-01-01

    Microcapsules were prepared by in situ polymerization and microcapsulation. Tetraethyl orthosilicate was used as the core material and phenolic resin was used as the wall material in an emulsion system of polyacrylic and tetraethyl orthosilicate. The obtained microcapsules were slowly heated such that the core material was released by evaporation, leaving hollow-core spheres. The spheres were mixed with a phenolic resin-derived binder and molded to obtain a carbon foam precursor, which was ca...

  12. The Effect of Caramelization and Carbonization Temperatures toward Structural Properties of Mesoporous Carbon from Fructose with Zinc Borosilicate Activator

    OpenAIRE

    Tutik Setianingsih; Indriana Kartini; Yateman Arryanto

    2014-01-01

    Mesoporous carbon was prepared from fructose using zinc borosilicate (ZBS) activator. The synthesis involves caramelization and carbonization processes. The effect of both process temperature toward porosity and functional group of carbon surface are investigated in this research. The caramelization was conducted hydrothermally at 85 and 100 °C, followed by thermally 130 °C. The carbonization was conducted at various temperatures (450–750 °C). The carbon-ZBS composite were washed by using HF ...

  13. Photoconductivity of Activated Carbon Fibers

    Science.gov (United States)

    Kuriyama, K.; Dresselhaus, M. S.

    1990-08-01

    The photoconductivity is measured on a high-surface-area disordered carbon material, namely activated carbon fibers, to investigate their electronic properties. Measurements of decay time, recombination kinetics and temperature dependence of the photoconductivity generally reflect the electronic properties of a material. The material studied in this paper is a highly disordered carbon derived from a phenolic precursor, having a huge specific surface area of 1000--2000m{sup 2}/g. Our preliminary thermopower measurements suggest that this carbon material is a p-type semiconductor with an amorphous-like microstructure. The intrinsic electrical conductivity, on the order of 20S/cm at room temperature, increases with increasing temperature in the range 30--290K. In contrast with the intrinsic conductivity, the photoconductivity in vacuum decreases with increasing temperature. The recombination kinetics changes from a monomolecular process at room temperature to a biomolecular process at low temperatures. The observed decay time of the photoconductivity is {approx equal}0.3sec. The magnitude of the photoconductive signal was reduced by a factor of ten when the sample was exposed to air. The intrinsic carrier density and the activation energy for conduction are estimated to be {approx equal}10{sup 21}/cm{sup 3} and {approx equal}20meV, respectively. The majority of the induced photocarriers and of the intrinsic carriers are trapped, resulting in the long decay time of the photoconductivity and the positive temperature dependence of the conductivity.

  14. Removal of Heavy Metal Ions with Acid Activated Carbons Derived from Oil Palm and Coconut Shells

    Directory of Open Access Journals (Sweden)

    Mokhlesur M. Rahman

    2014-05-01

    Full Text Available In this work, batch adsorption experiments were carried out to investigate the suitability of prepared acid activated carbons in removing heavy metal ions such as nickel(II, lead(II and chromium(VI. Acid activated carbons were obtained from oil palm and coconut shells using phosphoric acid under similar activation process while the differences lie either in impregnation condition or in both pretreatment and impregnation conditions. Prepared activated carbons were modified by dispersing hydrated iron oxide. The adsorption equilibrium data for nickel(II and lead(II were obtained from adsorption by the prepared and commercial activated carbons. Langmuir and Freundlich models fit the data well. Prepared activated carbons showed higher adsorption capacity for nickel(II and lead(II. The removal of chromium(VI was studied by the prepared acid activated, modified and commercial activated carbons at different pH. The isotherms studies reveal that the prepared activated carbon performs better in low concentration region while the commercial ones in the high concentration region. Thus, a complete adsorption is expected in low concentration by the prepared activated carbon. The kinetics data for Ni(II, Pb(II and Cr(VI by the best selected activated carbon fitted very well to the pseudo-second-order kinetic model.

  15. The Adsorption Mechanism of Modified Activated Carbon on Phenol

    Directory of Open Access Journals (Sweden)

    Lin J. Q.

    2016-01-01

    Full Text Available Modified activated carbon was prepared by thermal treatment at high temperature under nitrogen flow. The surface properties of the activated carbon were characterized by Boehm titration, BET and point of zero charge determination. The adsorption mechanism of phenol on modified activated carbon was explained and the adsorption capacity of modified activated carbon for phenol when compared to plain activated carbon was evaluated through the analysis of adsorption isotherms, thermodynamic and kinetic properties. Results shows that after modification the surface alkaline property and pHpzc value of the activated carbon increase and the surface oxygen-containing functional groups decrease. The adsorption processes of the plain and modified carbon fit with Langmuir isotherm equation well, and the maximum adsorption capacity increase from 123.46, 111.11, 103.09mg/g to 192.31, 178.57, 163,93mg/g under 15, 25 and 35°C after modification, respectively. Thermodynamic parameters show that the adsorption of phenol on activated carbon is a spontaneously exothermic process of entropy reduction, implying that the adsorption is a physical adsorption. The adsorption of phenol on activated carbon follows the pseudo-second-order kinetics (R2>0.99. The optimum pH of adsorption is 6~8.

  16. Preparation of Fiber Based Binder Materials to Enhance the Gas Adsorption Efficiency of Carbon Air Filter.

    Science.gov (United States)

    Lim, Tae Hwan; Choi, Jeong Rak; Lim, Dae Young; Lee, So Hee; Yeo, Sang Young

    2015-10-01

    Fiber binder adapted carbon air filter is prepared to increase gas adsorption efficiency and environmental stability. The filter prevents harmful gases, as well as particle dusts in the air from entering the body when a human inhales. The basic structure of carbon air filter is composed of spunbond/meltblown/activated carbon/bottom substrate. Activated carbons and meltblown layer are adapted to increase gas adsorption and dust filtration efficiency, respectively. Liquid type adhesive is used in the conventional carbon air filter as a binder material between activated carbons and other layers. However, it is thought that the liquid binder is not an ideal material with respect to its bonding strength and liquid flow behavior that reduce gas adsorption efficiency. To overcome these disadvantages, fiber type binder is introduced in our study. It is confirmed that fiber type binder adapted air filter media show higher strip strength, and their gas adsorption efficiencies are measured over 42% during 60 sec. These values are higher than those of conventional filter. Although the differential pressure of fiber binder adapted air filter is relatively high compared to the conventional one, short fibers have a good potential as a binder materials of activated carbon based air filter.

  17. [Study on the preparation and application of individual artificial bone with carbon/carbon composites].

    Science.gov (United States)

    Ni, Xinye; Qian, Nong; Zhou, Dong; Miao, Yunliang; Xiong, Xinbo; Lin, Tao; Chen, Da; Zhao, Gongyin; Zhong, Ping

    2013-12-01

    The present paper is aimed to study the preparation and application of individual artificial bone of carbon/carbon composites. Using computer tomography images (CT), we acquired a three-dimensional image. Firstly, we described bone contour line outlined with manual and automatic method by the binary volume data. Secondly, we created 3D object surface information by marching cubes. Finally, we converted this information to non-uniform rational B-spine (NURBS) by using geomagic software. Individual artificial bone with carbon/carbon composite was prepared through the CNC Machining Center. We replaced the humeral head of the tested rabbit, and then observed the effects of implantation in neuroimaging and pathological section. Using this method, we found that the bone shape processed and bone shape replaced was consistent. After implantation, the implant and the surrounding bone tissue bound closely, and bone tissue grew well on the surface of the implant. It has laid a sound foundation of the preparation using this method for individual artificial bone of carbon/carbon composite material.

  18. Preparation and Photocatalytic Properties of SnO2 Coated on Nitrogen-Doped Carbon Nanotubes

    OpenAIRE

    Lingling Wang; Long Shen; Luping Zhu; Haiying Jin; Naici Bing; Lijun Wang

    2012-01-01

    SnO2 nanoparticles coated on nitrogen-doped carbon nanotubes were prepared successfully via a simple wet-chemical route. The as-obtained SnO2/CNx composites were characterized using X-ray powder diffraction, scanning electron microscopy, and transmission electron microscopy. The photocatalytic activity of as-prepared SnO2/CNx for degradation Rhodamine B under UV light irradiation was investigated. The results show that SnO2/CNx nanocomposites have a higher photocatalytic activity than pure Sn...

  19. Activated carbon briquettes from biomass materials.

    Science.gov (United States)

    Amaya, Alejandro; Medero, Natalia; Tancredi, Néstor; Silva, Hugo; Deiana, Cristina

    2007-05-01

    Disposal of biomass wastes, produced in different agricultural activities, is frequently an environmental problem. A solution for such situation is the recycling of these residues for the production of activated carbon, an adsorbent which has several applications, for instance in the elimination of contaminants. For some uses, high mechanical strength and good adsorption characteristics are required. To achieve this, carbonaceous materials are conformed as pellets or briquettes, in a process that involves mixing and pressing of char with adhesive materials prior to activation. In this work, the influence of the operation conditions on the mechanical and surface properties of briquettes was studied. Eucalyptus wood and rice husk from Uruguay were used as lignocellulosic raw materials, and concentrated grape must from Cuyo Region-Argentina, as a binder. Different wood:rice and solid:binder ratios were used to prepare briquettes in order to study their influence on mechanical and surface properties of the final products.

  20. Modified Activated Carbon Prepared from Acorn Shells as a New Solid-Phase Extraction Sorbent for the Preconcentration and Determination of Trace Amounts of Nickel in Food Samples Prior to Flame Atomic Absorption Spectrometry.

    Science.gov (United States)

    Ebrahimi, Bahram

    2017-03-01

    A new solid-phase extraction (SPE) sorbent was introduced based on acidic-modified (AM) activated carbon (AC) prepared from acorn shells of native oak trees in Kurdistan. Hydrochloric acid (15%, w/w) and nitric acid (32.5%, w/w) were used to condition and modify AC. The IR spectra of AC and AM-AC showed that AM lead to the formation of increasing numbers of acidic functional groups on AM-AC. AM-AC was used in the SPE method for the extraction and preconcentration of Ni+2 prior to flame atomic absorption spectrometric determination at ng/mL levels in model and real food samples. Effective parameters of the SPE procedure, such as the pH of the solutions, sorbent dosage, extraction time, sample volume, type of eluent, and matrix ions, were considered and optimized. An enrichment factor of 140 was obtained. The calibration curve was linear with an R2 of 0.997 in the concentration range of 1-220 ng/mL. The RSD was 5.67% (for n = 7), the LOD was 0.352 ng/mL, and relative recoveries in vegetable samples ranged from 96.7 to 103.7%.

  1. Carbon-based acid catalyst from waste seed shells: preparation and characterization

    Directory of Open Access Journals (Sweden)

    Wang Li H.

    2015-12-01

    Full Text Available A carbon-based solid acid catalyst was prepared by the sulfonation of carbonized seed shells of Jatropha curcas (J. curcas L.. The structure of amorphous carbon consisting of polycyclic aromatic carbon sheets attached a high density of acidic SO3H groups (2.0 mmol · g−1 was identified with scanning electron microscopy (SEM, fourier transform infrared (FTIR spectroscopy, powder X-ray diffraction (XRD, and X-ray photoelectron spectroscopy (XPS. The performance of the solid acid catalyst was evaluated for biodiesel production in the esterification of oleic acid with methanol. 95.7% yield of biodiesel was obtained after 2 h reaction and the conversions with reused catalyst varied in the range of 95.7% to 95.1%, showing better activity and stability than commercial catalyst amberlyst-46. It was also observed that the prepared catalyst showed enhanced activity in the transesterification of triolein with methanol when compared with other solid acid catalysts. A synergistic effect results from the high density of SO3H groups and the good access of reactants to the acidic sites can be used to explain the excellent catalytic activity, as well as the strong affinity between the hydrophilic reactants and the neutral OH groups bonded to the polycyclic aromatic carbon rings.

  2. Process for preparing tapes from thermoplastic polymers and carbon fibers

    Science.gov (United States)

    Chung, Tai-Shung (Inventor); Furst, Howard (Inventor); Gurion, Zev (Inventor); McMahon, Paul E. (Inventor); Orwoll, Richard D. (Inventor); Palangio, Daniel (Inventor)

    1986-01-01

    The instant invention involves a process for use in preparing tapes or rovings, which are formed from a thermoplastic material used to impregnate longitudinally extended bundles of carbon fibers. The process involves the steps of (a) gas spreading a tow of carbon fibers; (b) feeding the spread tow into a crosshead die; (c) impregnating the tow in the die with a thermoplastic polymer; (d) withdrawing the impregnated tow from the die; and (e) gas cooling the impregnated tow with a jet of air. The crosshead die useful in the instant invention includes a horizontally extended, carbon fiber bundle inlet channel, means for providing melted polymer under pressure to the die, means for dividing the polymeric material flowing into the die into an upper flow channel and a lower flow channel disposed above and below the moving carbon fiber bundle, means for applying the thermoplastic material from both the upper and lower channels to the fiber bundle, and means for withdrawing the resulting tape from the die.

  3. Activated, coal-based carbon foam

    Science.gov (United States)

    Rogers, Darren Kenneth; Plucinski, Janusz Wladyslaw

    2004-12-21

    An ablation resistant, monolithic, activated, carbon foam produced by the activation of a coal-based carbon foam through the action of carbon dioxide, ozone or some similar oxidative agent that pits and/or partially oxidizes the carbon foam skeleton, thereby significantly increasing its overall surface area and concurrently increasing its filtering ability. Such activated carbon foams are suitable for application in virtually all areas where particulate or gel form activated carbon materials have been used. Such an activated carbon foam can be fabricated, i.e. sawed, machined and otherwise shaped to fit virtually any required filtering location by simple insertion and without the need for handling the "dirty" and friable particulate activated carbon foam materials of the prior art.

  4. Adsorption Of Blue-Dye On Activated Carbons Produced From Rice ...

    African Journals Online (AJOL)

    The activated carbons prepared were used for the adsorption of blue-dye of concentration ranging from 100 to 2000 mg/l from aqueous solution. The results obtained indicated that ferric chloride-activated carbons produced from coconut coirpith are better adsorbents for blue-dye than those prepared from rice husk.

  5. APPLICATION OF ACTIVATED CARBON PREPARED FROM OLIVE ...

    African Journals Online (AJOL)

    g pore volume, essentially microporous, has been used for the adsorption of two basic dyes: Methylene Blue (MB) and Rhodamine B (RB) in aqueous solution. The equilibrium adsorption isotherms of the two dyes at 30°C shows Langmuir ...

  6. Nanocrystalline celluloses-assisted preparation of hierarchical carbon monoliths for hexavalent chromium removal.

    Science.gov (United States)

    Su, Haiping; Chong, Yanping; Wang, Jitong; Long, Donghui; Qiao, Wenming; Ling, Licheng

    2018-01-15

    Hierarchical porous carbon monoliths with a 3D framework were synthesized through a facile sol-gel process using resorcinol-melamine-formaldehyde (RMF) as carbon precursors, and nanocrystalline celluloses (NCCs) as the structural inducing agent, followed by ambient pressure drying and carbonization. Polymerization of the RMF resin occurs around the nanorod-like NCCs dispersed homogeneously in water, which is quite beneficial for the formation of an interconnected network and supports the rigid macroporous structure. A hierarchical porous carbon monolith with modest micropores and well-developed macropores was prepared after CO2 activation at 950°C. The microporous structure was generated from the network of RMF polymer chains, while the macroporous structure was formed from the interconnection of polymer networks induced by NCCs. The obtained carbon monolith has a large specific surface area of 1808m2g-1 and shows a high adsorption capacity of 463mgg-1 for toxic Cr(VI) ions. Moreover, the activated carbon monolith exhibits a high selectivity for Cr(VI) in the coexistence of several other metal ions. These outstanding advantages of carbon monoliths, including their micro/macroporous structures, rich functional groups, low cost and easy synthesis, endow them with potential for use in a wide range of applications. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Activated carbon from sugarcane bagasse ash for melanoidins recovery.

    Science.gov (United States)

    Kaushik, A; Basu, S; Singh, K; Batra, V S; Balakrishnan, M

    2017-09-15

    This work investigates the value added utilization of two sugar-distillery wastes: (i) melanoidins, which are complex Maillard reaction products in molasses distillery wastewater, and (ii) unburnt carbon in sugarcane bagasse ash. Activated unburnt carbon (AUC), prepared by deashing and steam activation, had properties comparable to commercial activated carbon (CAC). Both carbons are suitable for melanoidins adsorption followed by desorption using 25% pyridine solution. For AUC, the equilibrium adsorption data is well described by Langmuir isotherm up to 35 °C while Freundlich model fits better at higher temperature. Adsorption using CAC followed Freundlich isotherm at all temperatures. Both carbons followed pseudo second order kinetics and displayed endothermic physisorption. Recovery of melanoidins from AUC (78%) was close to that observed with CAC (80%). Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Composite supercapacitor electrodes made of activated carbon ...

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 36; Issue 4. Composite supercapacitor electrodes made of activated carbon/PEDOT:PSS and activated carbon/doped PEDOT. T S Sonia P A ... Carbon materials; composite materials; electrodeposition; energy storage and conversion; thin films; conducting polymers.

  9. Activated Carbon Fiber Monoliths as Supercapacitor Electrodes

    Directory of Open Access Journals (Sweden)

    Gelines Moreno-Fernandez

    2017-01-01

    Full Text Available Activated carbon fibers (ACF are interesting candidates for electrodes in electrochemical energy storage devices; however, one major drawback for practical application is their low density. In the present work, monoliths were synthesized from two different ACFs, reaching 3 times higher densities than the original ACFs’ apparent densities. The porosity of the monoliths was only slightly decreased with respect to the pristine ACFs, the employed PVDC binder developing additional porosity upon carbonization. The ACF monoliths are essentially microporous and reach BET surface areas of up to 1838 m2 g−1. SEM analysis reveals that the ACFs are well embedded into the monolith structure and that their length was significantly reduced due to the monolith preparation process. The carbonized monoliths were studied as supercapacitor electrodes in two- and three-electrode cells having 2 M H2SO4 as electrolyte. Maximum capacitances of around 200 F g−1 were reached. The results confirm that the capacitance of the bisulfate anions essentially originates from the double layer, while hydronium cations contribute with a mixture of both, double layer capacitance and pseudocapacitance.

  10. The effects of activation temperature on physico-chemical characteristics of activated carbons derived from biomass wastes

    Science.gov (United States)

    Sutrisno, Bachrun; Hidayat, Arif

    2015-12-01

    This research focused on investigating in the effect of activation temperature on the physico-chemical properties of palm empty fruit bunch (PEFB) based activated carbon prepared by physical activation with carbon dioxide. The activation temperature was studied in the range of 400-800°C by keeping the activation temperature at 800°C for 120 min. It was found that the porous properties of activated carbon decreased with an increase in carbonization temperature. The activated carbons prepared at the highest activation temperature at 800°C and activation time of 120 min gave the activated carbon with the highest of BET surface area and pore volume of 938 m2/g and 0.4502 cm3/g, respectively

  11. Cryogenic Adsorption of Nitrogen and Carbon Dioxide in Activated Carbon

    Science.gov (United States)

    Shen, Fuzhi; Liu, Huiming; Xu, Dong; Zhang, Hengcheng; Lu, Junfeng; Li, Laifeng

    2017-09-01

    Activated carbon have been used for a long time at low temperature for cryogenic applications. The knowledge of adsorption characteristics of activated carbon at cryogenic temperature is essential for some specific applications. However, such experimental data are very scare in the literature. In order to measure the adsorption characteristics of activated carbon under variable cryogenic temperatures, an adsorption measurement device was presented. The experiment system is based on the commercially available PCT-pro adsorption analyzer coupled to a two-stage Gifford McMahon refrigerator, which allows the sample to be cooled to 4.2K. Cryogenic environment can be maintained steadily without the cryogenic liquid through the cryocooler and temperature can be controlled precisely between 5K and 300K by the temperature controller. Adsorption measurements were performed in activated carbon for carbon dioxide and nitrogen and the adsorption isotherm were obtained.

  12. Preparation of a Ni-MgO-Al2O3 catalyst with high activity and resistance to potassium poisoning during direct internal reforming of methane in molten carbonate fuel cells

    Science.gov (United States)

    Jang, Won-Jun; Jung, You-Shick; Shim, Jae-Oh; Roh, Hyun-Seog; Yoon, Wang Lai

    2018-02-01

    Steam reforming of methane (SRM) is conducted using a series of Ni-MgO-Al2O3 catalysts for direct internal reforming (DIR) in molten carbonate fuel cells (MCFCs). Ni-MgO-Al2O3 catalysts are prepared by the homogeneous precipitation method with a variety of MgO loading amounts ranging from 3 to 15 wt%. In addition, each precursor concentrations are systemically changed (Ni: 1.2-4.8 mol L-1; Mg: 0.3-1.2 mol L-1; Al: 0.4-1.6 mol L-1) at the optimized composition (10 wt% MgO). The effects of MgO loading and precursor concentration on the catalytic performance and resistance against poisoning of the catalyst by potassium (K) are investigated. The Ni-MgO-Al2O3 catalyst with 10 wt% MgO and the original precursor concentration (Ni: 1.2 mol L-1; Mg: 0.3 mol L-1; Al: 0.4 mol L-1) exhibits the highest CH4 conversion and resistance against K poisoning even at the extremely high gas space velocity (GHSV) of 1,512,000 h-1. Excellent SRM performance of the Ni-MgO-Al2O3 catalyst is attributed to strong metal (Ni) to alumina support interaction (SMSI) when magnesium oxide (MgO) is co-precipitated with the Ni-Al2O3. The enhanced interaction of the Ni with MgO-Al2O3 support is found to protect the active Ni species against K poisoning.

  13. Sorption of lead from aqueous solution by modified activated carbon ...

    African Journals Online (AJOL)

    The present study aims to develop a simple and rapid procedure for lead (II) removal. Laboratory-scale adsorption experiments were conducted aiming to remove lead from water samples. They were based on using powdered activated carbon (PACI), which was prepared from olive stones generated, as plant wastes, and ...

  14. Determination of ascorbic acid in pharmaceutical preparation and fruit juice using modified carbon paste electrode

    Directory of Open Access Journals (Sweden)

    Simona Žabčíková

    2016-06-01

    Full Text Available Acrobic acid is key substance in the human metabolism and the rapid and accurate determination in food is of a great interest. Ascorbic acid is an electroactive compound, however poorly responded on the bare carbon paste electrodes. In this paper, brilliant cresyl blue and multi-walled carbon nanotubes were used for the modification of carbon paste electrode. Brilliant cresyl blue acts as a mediator improving the transition of electrons, whereas multiwalled carbon nanotubes increased the surface of the electrode. Both brilliant cresyl blue and multiwalled carbon nanotubes were added directly to the composite material. The electrochemical behavior of modified electode was determined in electrolyte at various pH, and the effect of the scan rate was also performed. It was shown that the electrochemical process on the surface of the modified carbon paste electrode was diffusion-controlled. The resulted modified carbon paste electrode showed a good electrocatalytic activity towards the oxidation of ascorbic acid at a reduced overpotential of +100 mV descreasing the risk of interferences. A linear response of the ascorbic acid oxidation current measured by the amperometry in the range of 0.1 - 350 µmol.L-1 was obtained applying the sensor for the standard solution. The limit of detection and limit of quantification was found to be 0.05 and 0.15 µmol.L-1, respectively. The novel method was applied for the determination of ascorbic acid in pharmaceutical vitamin preparation and fruit juice, and the results were in good agreement with the standard HPLC method. The presented modification of carbon paste electrode is suitable for the fast, sensitive and very accurate determination of ascorbic acid in fruit juices and pharmaceutical preparation.

  15. Preparation Of Melt Spun Electroconductive Fine Fibres Containing Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    Mirjalili Mohammad

    2015-06-01

    Full Text Available Preparation of electroconductive fine fibres containing carbon nanotubes (CNTs by melt spinning was the main goal of the present study. In this regard, the influence of the main operating parameters such as type of polymer used (polyester, polypropylene and polyamide, type and concentration of the CNTs on conductivity, and mechanical and thermal properties of the melt spun fibres was studied. The conductivity of melt spun fibres was measured based on the method developed by Morton and Hearl. The morphologies of the CNTs–polymer composite fibres were studied by scanning electron microscopy. Thermal behaviours and mechanical properties of the CNTs–polymer composite fibres were investigated using differential scanning calorimetry and tearing tester, respectively. The results reveal that using CNTs had tangible effect on electrical, thermal and mechanical properties of the melt spun fibres. Also, polyamide had a better dispersion of CNTs and correspondingly lower surface resistivity.

  16. Polymer/Carbon-Based Hybrid Aerogels: Preparation, Properties and Applications.

    Science.gov (United States)

    Zuo, Lizeng; Zhang, Youfang; Zhang, Longsheng; Miao, Yue-E; Fan, Wei; Liu, Tianxi

    2015-10-09

    Aerogels are synthetic porous materials derived from sol-gel materials in which the liquid component has been replaced with gas to leave intact solid nanostructures without pore collapse. Recently, aerogels based on natural or synthetic polymers, called polymer or organic aerogels, have been widely explored due to their porous structures and unique properties, such as high specific surface area, low density, low thermal conductivity and dielectric constant. This paper gives a comprehensive review about the most recent progresses in preparation, structures and properties of polymer and their derived carbon-based aerogels, as well as their potential applications in various fields including energy storage, adsorption, thermal insulation and flame retardancy. To facilitate further research and development, the technical challenges are discussed, and several future research directions are also suggested in this review.

  17. Polymer/Carbon-Based Hybrid Aerogels: Preparation, Properties and Applications

    Science.gov (United States)

    Zuo, Lizeng; Zhang, Youfang; Zhang, Longsheng; Miao, Yue-E; Fan, Wei; Liu, Tianxi

    2015-01-01

    Aerogels are synthetic porous materials derived from sol-gel materials in which the liquid component has been replaced with gas to leave intact solid nanostructures without pore collapse. Recently, aerogels based on natural or synthetic polymers, called polymer or organic aerogels, have been widely explored due to their porous structures and unique properties, such as high specific surface area, low density, low thermal conductivity and dielectric constant. This paper gives a comprehensive review about the most recent progresses in preparation, structures and properties of polymer and their derived carbon-based aerogels, as well as their potential applications in various fields including energy storage, adsorption, thermal insulation and flame retardancy. To facilitate further research and development, the technical challenges are discussed, and several future research directions are also suggested in this review. PMID:28793602

  18. Porous texture evolution in Nomex-derived activated carbon fibers.

    Science.gov (United States)

    Villar-Rodil, S; Denoyel, R; Rouquerol, J; Martínez-Alonso, A; Tascón, J M D

    2002-08-01

    In the present work, the textural evolution of a series of activated carbon fibers with increasing burn-off degree, prepared by the pyrolysis and steam activation of Nomex aramid fibers, is followed by measurements of physical adsorption of N(2) (77 K) and CO(2) (273 K) and immersion calorimetry into different liquids (dichloromethane, benzene, cyclohexane). The immersion calorimetry results are discussed in depth, paying special attention to the choice of the reference material. The activated carbon fibers studied possess an essentially homogeneous microporous texture, which suggests that these materials may be applied in gas separation, either directly or with additional CVD treatment.

  19. Studies of activated carbon and carbon black for supercapacitor applications

    Energy Technology Data Exchange (ETDEWEB)

    Richner, R.; Mueller, S.; Koetz, R.; Wokaun, A. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    Carbon Black and activated carbon materials providing high surface areas and a distinct pore distribution are prime materials for supercapacitor applications at frequencies < 0.5 Hz. A number of these materials were tested for their specific capacitance, surface and pore size distribution. High capacitance electrodes were manufactured on the laboratory scale with attention to ease of processability. (author) 1 fig., 1 ref.

  20. Production of activated carbon from peanut hill using phosphoric acid and microwave activation

    Directory of Open Access Journals (Sweden)

    Weerawat Clowutimon

    2015-06-01

    Full Text Available The optimum conditions for preparing activated carbon from peanut hulls by phosphoric acid and microwave activation were studied. Factors investigated in this study were temperature of carbonization at 300, 350, 400 and 450๐ C, and time of carbonization at 30, 60 and 90 minutes. The optimum yield was observed that carbonization temperature of 400๐ C and time at 60 minutes, respectively. The yield of charcoal was 39% and the f ix carbon was 69%. Then the charcoal was activated by phosphoric acid and microwave irradiation, respectively. The effect of the weight per volume ratios of charcoal to activating acid (1:1, 1:2 and 2:1(W/V, microwave power at (activated 300, 500 and 700 watts, and activated time (30, 60 and 90 seconds were studied. The results showed that the optimum conditions for activating peanut charcoal were 1:2 (W/V charcoal per activating acid, microwave power 700 watts for 90 seconds. The results yielding maximum surface area by BET method was 303.1 m2 /g and pore volume was 0.140 cm3 /g. An efficiency of maximum iodine adsorption was 418 mg iodine/g activated carbon. Comparing the adsorption efficiency of non- irradiated and irradiated activated carbon, the efficiency of irradiated activated carbon improved up to 31%, due to its larger surface area and pore volume.

  1. Adsorptive removal of sulfate from acid mine drainage by polypyrrole modified activated carbons: Effects of polypyrrole deposition protocols and activated carbon source.

    Science.gov (United States)

    Hong, Siqi; Cannon, Fred S; Hou, Pin; Byrne, Tim; Nieto-Delgado, Cesar

    2017-10-01

    Polypyrrole modified activated carbon was used to remove sulfate from acid mine drainage water. The polypyrrole modified activated carbon created positively charged functionality that offered elevated sorption capacity for sulfate. The effects of the activated carbon type, approach of polymerization, preparation temperature, solvent, and concentration of oxidant solution over the sulfate adsorption capacity were studied at an array of initial sulfate concentrations. A hardwood based activated carbon was the more favorable activated carbon template, and this offered better sulfate removal than when using bituminous based activated carbon or oak wood activated carbon as the template. The hardwood-based activated carbon modified with polypyrrole removed 44.7 mg/g sulfate, and this was five times higher than for the pristine hardwood-based activated carbon. Various protocols for depositing the polypyrrole onto the activated carbon were investigated. When ferric chloride was used as an oxidant, the deposition protocol that achieved the most N + atomic percent (3.35%) while also maintaining the least oxygen atomic percent (6.22%) offered the most favorable sulfate removal. For the rapid small scale column tests, when processing the AMD water, hardwood-based activated carbon modified with poly pyrrole exhibited 33 bed volume compared to the 5 bed volume of pristine activated carbons. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Attempts to prepare an all-carbon indigoid system

    Directory of Open Access Journals (Sweden)

    Şeref Yildizhan

    2015-03-01

    Full Text Available First attempts are described to prepare a precursor for an all-carbon analog of indigo, the tetracyclic triene 4. Starting from indan-2-one (9 the α-methylene ketone 13 was prepared. Upon subjecting this compound to a McMurry coupling reaction, it dimerized to the bis-indene derivative 17, rather than providing the tetramethyl derivative of 4, the hydrocarbon 14. In a second approach, indan-1-one (18 was dimerized to the conjugated enedione 21 through the bis-1-indene dimer 19. All attempts to methylenate 21 failed, however. When 19 was treated with the Tebbe reagent, the dimer 23 was produced, presumably through a Cope reaction of the intermediately generated isomer 22. The bis-indene derivative 23 can be alkylated with 1,2-dibromoethane to produce a 1:1 mixture of the spiro compounds 24 and 25. Although 9 could be reductively dimerized to 30, the conversion of this olefin to 14 failed.

  3. Preparation and characterization of dopamine-decorated hydrophilic carbon black

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Lijun; Lu Yonglai [State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029 (China); Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials, Beijing 100029 (China); Wang Yiqing [State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029 (China); Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing 100029 (China); Zhang Liqun [State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029 (China); Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials, Beijing 100029 (China); Wang Wencai, E-mail: wangw@mail.buct.edu.cn [State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029 (China); Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing 100029 (China)

    2012-05-01

    Inspired by the bio-adhesive proteins secreted by mussels for attachment to almost all wet substrates, a facile method involving oxidative polymerization of dopamine was proposed to prepare highly hydrophilic carbon black (CB) particles. A self-assembled polydopamine (PDA) ad-layer was formed via the oxidative polymerization of dopamine on the surface of CB simply by dipping the CB into an alkaline dopamine solution and mildly stirring at room temperature. The process is simple, controllable, and environment-friendly. The surface composition and structure of the CB were characterized by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). The surface morphology of the CB was observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results showed that the PDA ad-layer was successfully deposited on the CB surfaces. The PDA-functionalized CB (CB-PDA) gave a stable colloidal dispersion in water. Contact angle measurement results indicated that the hydrophilicity of CB was significantly improved after dopamine modification. TGA results confirmed that the modified CB maintained good heat resistance. The method provided a facile route to prepare hydrophilic CB having terminal hydroxyl groups.

  4. Preparation of carbon-11 labelled prazosin, a potent and selective. cap alpha. /sub 1/-adrenoreceptor antagonist

    Energy Technology Data Exchange (ETDEWEB)

    Ehrin, E.; Crouzel, C.; Luthra, S.K.; Pike, V.W.

    1988-02-01

    The ..cap alpha../sub 1/-adrenoreceptor antagonist, Prazosin : 2-(4-(2-furoyl) piperazin-1-yl)-4-amino-6,7-dimethoxyquinazoline, has been labelled with carbon-11 for in vivo studies of ..cap alpha../sub 1/-adrenoreceptors using positron emission tomography. The preparation of (2-/sup 11/C) furoyl chloride, from cyclotron-produced (/sup 11/C) carbon dioxide, and its reaction with the secondary amine, 2-(piperazin-1-yl)-4-amino-6,7-dimethoxyquinazoline, provides a fast (35 min) route to carbon-11 labelled prazosin in high radiochemical yield (30-40%, decay-corrected) with high specific activity (26-37 GBq..mu..mol, 0.7-1.0 Ci..mu..mol).

  5. Development of porosity and surface chemistry of textile waste jute-based activated carbon by physical activation.

    Science.gov (United States)

    Chen, Weifang; He, Feifei; Zhang, Sijia; Xv, Hui; Xv, Zhihua

    2018-01-25

    Two-step physical activation was used to prepare activated carbon from textile waste jute. Raw material was first carbonized under nitrogen and then activated by CO 2 . Based on yield and pore structure, the optimal carbonization temperature and time were 500 °C and 60 min, respectively. Carbonized sample was next activated. The development of porosity and surface chemistry was highly dependent on activation temperature and time. Activated carbon produced at 800 °C was predominantly microporous while that produced at 900 °C was more mesoporous and macroporous. The shift from microporosity to mesoporosity could be used to produce either microporous or mesoporous carbon just by changing the activation temperature. Activation also changed the surface chemistry and created a more carbonaceous structure. The jute-based activated carbon was mostly powdered in form, slightly acidic and effective in adsorbing both heavy metals and organics.

  6. Preparation and characterization of hierarchical porous carbons derived from solid leather waste for supercapacitor applications.

    Science.gov (United States)

    Konikkara, Niketha; Kennedy, L John; Vijaya, J Judith

    2016-11-15

    Utilization of crust leather waste (CLW) as precursors for the preparation of hierarchical porous carbons (HPC) were investigated. HPCs were prepared from CLW by pre-carbonization followed by chemical activation using KOH at relatively high temperatures. Textural properties of HPC's showed an extent of micro-and mesoporosity with maximum BET surface area of 716m(2)/g. Inducements of graphitic planes in leather waste derived carbons were observed from X-ray diffraction and HR-TEM analysis. Microstructure, thermal behavior and surface functional groups were identified using FT-Raman, thermo gravimetric analysis and FT-IR techniques. HPCs were evaluated for electrochemical properties by cyclic voltammetry (CV), galvanostatic charge/discharge (GCD) and electrochemical impedance spectroscopy (EIS) by three electrode system. CLC9 sample showed a maximum capacitance of 1960F/g in 1M KCl electrolyte. Results achieved from rectangular curves of CV, GCD symmetric curves and Nyquist plots show that the leather waste carbon is suitable to fabricate supercapacitors as it possess high specific capacitance and electrochemical cycle stability. The present study proposes an effective method for solid waste management in leather industry by the way of converting toxic leather waste to new graphitic porous carbonaceous materials as a potential candidate for energy storage devices. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Preparation and characterization of hierarchical porous carbons derived from solid leather waste for supercapacitor applications

    Energy Technology Data Exchange (ETDEWEB)

    Konikkara, Niketha [Materials Division, School of Advanced Sciences, Vellore Institute of Technology (VIT) University, Chennai Campus, Chennai 600 127 (India); Kennedy, L. John, E-mail: jklsac14@yahoo.co.in [Materials Division, School of Advanced Sciences, Vellore Institute of Technology (VIT) University, Chennai Campus, Chennai 600 127 (India); Vijaya, J. Judith [Catalysis and Nanomaterials Research Laboratory, Department of Chemistry, Loyola College (Autonomous) Chennai 600 034 (India)

    2016-11-15

    Highlights: • Solid leather waste was used as a precursor for preparing HPCs—waste to energy storage. • The textural, structural and morphological properties show the hierarchical porous nature. • Porous carbon with surface area 716 m{sup 2}/g and pore volume 0.4030 cm{sup 3}/g has been produced. • HPCs based supercapacitor electrodes are fabricated with three electrode system in 1 M KCl. • Specific capacitance of 1960 F/g is achieved at scan rate of 1 mV/s in 1 M KCl. - Abstract: Utilization of crust leather waste (CLW) as precursors for the preparation of hierarchical porous carbons (HPC) were investigated. HPCs were prepared from CLW by pre-carbonization followed by chemical activation using KOH at relatively high temperatures. Textural properties of HPC’s showed an extent of micro-and mesoporosity with maximum BET surface area of 716 m{sup 2}/g. Inducements of graphitic planes in leather waste derived carbons were observed from X-ray diffraction and HR-TEM analysis. Microstructure, thermal behavior and surface functional groups were identified using FT-Raman, thermo gravimetric analysis and FT-IR techniques. HPCs were evaluated for electrochemical properties by cyclic voltammetry (CV), galvanostatic charge/discharge (GCD) and electrochemical impedance spectroscopy (EIS) by three electrode system. CLC9 sample showed a maximum capacitance of 1960 F/g in 1 M KCl electrolyte. Results achieved from rectangular curves of CV, GCD symmetric curves and Nyquist plots show that the leather waste carbon is suitable to fabricate supercapacitors as it possess high specific capacitance and electrochemical cycle stability. The present study proposes an effective method for solid waste management in leather industry by the way of converting toxic leather waste to new graphitic porous carbonaceous materials as a potential candidate for energy storage devices.

  8. Calcium phosphorus bio-coating on carbon/carbon composites: Preparation, shear strength and bioactivity

    Science.gov (United States)

    Su, Yangyang; Li, Kezhi; Zhang, Leilei; Liu, Shoujie; Yuan, Ye; He, Song

    2017-10-01

    Microwave hydrothermal (MH) combining supersonic atmospheric plasma sprayed (SAPS) calcium phosphorus (Ca-P) bio-coatings on carbon/carbon (C/C) composite has been widely used due to their osteoconductivity and osteoproductivity. However, the erratic shear strength between coatings prepared only by SAPS (outer coating) and C/C substrates has attached more attention over the implant failure. Adding a coating prepared by MH (inner coating) before SAPS can possess superior shear strength to conventional outer coating. The inner coating with fine Ca-P particles was prepared through a unique MH method under different concentrations (10, 500 and 1000 mmol/L). The influence of concentration on microstructure, phase composition, roughness and shear strength are investigated in this paper. In particularly, the roughness of inner coatings on C/C substrates was found to related to the morphologies and particle size. Results showed that inner coatings have higher roughness which was beneficial for the promotion of shear strength between the obtained Ca-P bio-coating and the C/C substrates. Subsequently, the specimens were immersed in a simulated body fluid (SBF) to investigate the bioactivity.

  9. Fuzzy logic modeling of Pb (II) sorption onto mesoporous NiO/ZnCl2-Rosa Canina-L seeds activated carbon nanocomposite prepared by ultrasound-assisted co-precipitation technique.

    Science.gov (United States)

    Javadian, Hamedreza; Ghasemi, Maryam; Ruiz, Montserrat; Sastre, Ana Maria; Asl, Seyed Mostafa Hosseini; Masomi, Mojtaba

    2018-01-01

    In this study, NiO/Rosa Canina-L seeds activated carbon nanocomposite (NiO/ACNC) was prepared by adding dropwise NaOH solution (2mol/L) to raise the suspension pH to around 9 at room temperature under ultrasonic irradiation (200W) as an efficient method and characterized by FE-SEM, FTIR and N 2 adsorption-desorption isotherm. The effect of different parameters such as contact time (0-120min), initial metal ion concentration (25-200mg/L), temperature (298, 318 and 333K), amount of adsorbent (0.002-0.007g) and the solution's initial pH (1-7) on the adsorption of Pb (II) was investigated in batch-scale experiments. The equilibrium data were well fitted by Langmuir model type 1 (R 2 >0.99). The maximum monolayer adsorption capacity (q m ) of NiO/ACNC was 1428.57mg/L. Thermodynamic parameters (ΔG°, ΔH° and ΔS°) were also calculated. The results showed that the adsorption of Pb (II) onto NiO/ACNC was feasible, spontaneous and exothermic under studied conditions. In addition, a fuzzy-logic-based model including multiple inputs and one output was developed to predict the removal efficiency of Pb (II) from aqueous solution. Four input variables including pH, contact time (min), dosage (g) and initial concentration of Pb (II) were fuzzified using an artificial intelligence-based approach. The fuzzy subsets consisted of triangular membership functions with eight levels and a total of 26 rules in the IF-THEN approach which was implemented on a Mamdani-type of fuzzy inference system. Fuzzy data exhibited small deviation with satisfactory coefficient of determination (R 2 >0.98) that clearly proved very good performance of fuzzy-logic-based model in prediction of removal efficiency of Pb (II). It was confirmed that NiO/ACNC had a great potential as a novel adsorbent to remove Pb (II) from aqueous solution. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. (Hevea brasiliensis) SEED PERICARP-ACTIVATED CARBON

    African Journals Online (AJOL)

    2012-11-03

    Nov 3, 2012 ... abattoir waste water, activated carbon, adsorption isotherms, iron (III) chloride, lagergren equations, rubber seed pericarp. 1. ... threat to the environment, due to their acute toxic- ity to many life ... Wastewater Treatment Adsorption Potential of Rubber Seed Pericarp-Activated Carbon 347 and adsorption [10] ...

  11. Method for the preparation of carbon fiber from polyolefin fiber precursor

    Energy Technology Data Exchange (ETDEWEB)

    Naskar, Amit Kumar; Hunt, Marcus Andrew; Saito, Tomonori

    2017-11-28

    Methods for the preparation of carbon fiber from polyolefin fiber precursor, wherein the polyolefin fiber precursor is partially sulfonated and then carbonized to produce carbon fiber. Methods for producing hollow carbon fibers, wherein the hollow core is circular- or complex-shaped, are also described. Methods for producing carbon fibers possessing a circular- or complex-shaped outer surface, which may be solid or hollow, are also described.

  12. Novel Activated Carbons from Agricultural Wastes and their Characterization

    Directory of Open Access Journals (Sweden)

    S. Karthikeyan

    2008-01-01

    Full Text Available Solid waste disposal has become a major problem in India, Either it has to be disposed safely or used for the recovery of valuable materials as agricultural wastes like turmeric waste, ferronia shell waste, jatropha curcus seed shell waste, delonix shell waste and ipomea carnia stem. Therefore these wastes have been explored for the preparation of activated carbon employing various techniques. Activated carbons prepared from agricultural solid wastes by chemical activation processes shows excellent improvement in the surface characteristics. Their characterization studies such as bulk density, moisture content, ash content, fixed carbon content, matter soluble in water, matter soluble in acid, pH, decolourising power, phenol number, ion exchange capacity, ion content and surface area have been carried out to assess the suitability of these carbons as absorbents in the water and wastewater. For anionic dyes (reactive, direct, acid a close relationship between the surface area and surface chemical groups of the modified activated carbon and percentage of dye removal by adsorption can be observed. Cationic dyes large amount of surface chemical groups present in the sample (mainly carboxylic, anhydrides, lactones and phenols etc. are good anchoring sites for adsorption. The present study reveals the recovery of valuable adsorbents from readily and cheaply available agriculture wastes.

  13. REMOVAL OF IMIDACLOPRID USING ACTIVATED CARBON ...

    African Journals Online (AJOL)

    wastewater. KEY WORDS: Chemical activation, Adsorption, Activated carbon, Pesticide removal, Waste treatment. INTRODUCTION. Pesticides (insecticide, weed-killer, fungicide, etc.) are substances used in a wide range of applications especially in agriculture and households to eradicate pests including insects, wild.

  14. Preparation and structural characterization of turbostratic-carbon/graphene derived from amylose film

    Science.gov (United States)

    Sazali, N. E. S.; Deraman, M.; Omar, R.; Othman, M. A. R.; Suleman, M.; Shamsudin, S. A.; Tajuddin, N. S. M.; Hanappi, M. F. Y. M.; Hamdan, E.; Nor, N. S. M.; Basri, N. H.

    2016-11-01

    In this study, we report the preparation of turbostratic-carbon/graphene from biomass amylose film by carbonization (N2 gas) and activation (CO2 gas) over different temperatures 600, 700, 800, 900, and 1000 °C, respectively. The Raman spectroscopy results of the produced samples show that the values of the ID/IG ratio ranging from 0.75 to 0.99 are comparable to that of the commercial multilayer graphene and KOH treated multilayer graphene. The X-ray diffraction results of the produced samples show that a small decrease in the d002 (˜0.62 %) and d100 (˜0.57 %) values and a larger decrease in Lc (˜8.6 %) and La (˜27.2 %) values occurs as the carbonization and activation temperature increases, indicating that the increase in temperature has an effect on the growth of microcrystallites during carbonization and activation. This study demonstrates the potential of the amylose film to be used as a precursor for producing graphene flakes.

  15. Evaluation for characteristics of active carbon electrodes air cell

    Energy Technology Data Exchange (ETDEWEB)

    Kano, Gentaro; Horita, Kiyoshi; Nishino, Hiromi

    1988-04-15

    Characteristics as an air electrode in alkali solutions were investigated in connection with catalyst effect of manganese oxides, on Teflon-bonded active carbon electrodes prepared with Pittsburg active carbon, acetylene black and manganese oxide consisting of Mn/sub 5/O/sub 8/ and Mn/sub 3/O/sub 4/. As the results, the active carbon electrode containing 20wt% acethylene black and heat treated at 400C exhibited lower resistance polarization and better carbon electrode characteristics than same active carcon electrode heat treated at lower temperatures. The carbon electrode to which 20wt% manganese oxide was added, exhibited about two times larger exchange current density than that without manganese oxide. The voltage-recovery characteristics of the active carbon electrode was greatlty improved in the presence of manganese oxide because the catalytic effect of manganese oxide contributed to the decomposition of HO/sub 2//sup -/ ion on the electrode interface just after the circiut was opened. (10 figs, 2 tabs, 10 refs)

  16. Preparation of carbon quantum dots based high photostability luminescent membranes.

    Science.gov (United States)

    Zhao, Jinxing; Liu, Cui; Li, Yunchuan; Liang, Jiyuan; Liu, Jiyan; Qian, Tonghui; Ding, Jianjun; Cao, Yuan-Cheng

    2017-06-01

    Urethane acrylate (UA) was used to prepare carbon quantum dots (C-dots) luminescent membranes and the resultants were examined with FT-IR, mechanical strength, scanning electron microscope (SEM) and quantum yields (QYs). FT-IR results showed the polyurethane acrylate (PUA) prepolymer -C = C-vibration at 1101 cm-1 disappeared but there was strong vibration at1687cm-1 which was contributed from the-C = O groups in cross-linking PUA. Mechanical strength results showed that the different quantity of C-dots loadings and UV-curing time affect the strength. SEM observations on the cross-sections of the membranes are uniform and have no structural defects, which prove that the C-dots are compatible with the water-soluble PUA resin. The C-dot loading was increased from 0 to 1 g, the maximum tensile stress was nearly 2.67 MPa, but the tensile strain was decreased from 23.4% to 15.1% and 7.2% respectively. QYs results showed that the C-dots in the membrane were stable after 120 h continuous irradiation. Therefore, the C-dots photoluminescent film is the promising material for the flexible devices in the future applications. Copyright © 2016 John Wiley & Sons, Ltd.

  17. Making Activated Carbon by Wet Pressurized Pyrolysis

    Science.gov (United States)

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

    2006-01-01

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

  18. Nanostructured Carbon Materials as Supports in the Preparation of Direct Methanol Fuel Cell Electrocatalysts

    Directory of Open Access Journals (Sweden)

    María Jesús Lázaro

    2013-08-01

    Full Text Available Different advanced nanostructured carbon materials, such as carbon nanocoils, carbon nanofibers, graphitized ordered mesoporous carbons and carbon xerogels, presenting interesting features such as high electrical conductivity and extensively developed porous structure were synthesized and used as supports in the preparation of electrocatalysts for direct methanol fuel cells (DMFCs. The main advantage of these supports is that their physical properties and surface chemistry can be tailored to adapt the carbonaceous material to the catalytic requirements. Moreover, all of them present a highly mesoporous structure, diminishing diffusion problems, and both graphitic character and surface area can be conveniently modified. In the present work, the influence of the particular features of each material on the catalytic activity and stability was analyzed. Results have been compared with those obtained for commercial catalysts supported on Vulcan XC-72R, Pt/C and PtRu/C (ETEK. Both a highly ordered graphitic and mesopore-enriched structure of these advanced nanostructured materials resulted in an improved electrochemical performance in comparison to the commercial catalysts assayed, both towards CO and alcohol oxidation.

  19. Ammonia Activation of Carbonized Polysaccharides and their Application for the Carbon Capture

    Energy Technology Data Exchange (ETDEWEB)

    Han, Tae Youl; Park, Seo Kyoung; Lee, Je Seung [Kyung Hee University, Seoul (Korea, Republic of)

    2016-05-15

    Porous carbons derived from polysaccharides (cellulose, chitosan, and alginic acid) have been prepared by heat treatment under N{sub 2} atmosphere and activated at high temperature under ammonia gas atmosphere. The CO{sub 2} adsorption capacities of prepared porous carbon materials and their dependence on the surface area and pore volume were investigated. The surface area of pristine carbon from cellulose, chitosan, and alginic acid at 800 .deg. C was measured as 406.5, 206.8, and 258.2 m{sup 2}/g with the pore volume of 0.27, 0.14, and 0.15 cm{sup 3}/g, respectively. The surface area and pore volume of carbons derived from cellulose, chitosan, and alginic acid further increased up to 976.6, 883.4, and 1031.9 m{sup 2}/g and 0.54, 0.45, and 0.65 cm{sup 3}/g, respectively, after the activation at high temperature under ammonia gas environment. The CO{sub 2} adsorption capacities of pristine carbons were measured as high as 1.85 mmol/g and further increased up to 2.44 mmol/g by ammonia activation.

  20. Preparation of catechol-linked chitosan/carbon nanocomposite-modified electrode and its applications

    Energy Technology Data Exchange (ETDEWEB)

    Jirimali, Harishchandra Digambar; Saravanakumar, Duraisamy; Shin, Woon Sup [Dept. of Chemistry and Interdisciplinary Program of Integrated Biotechnology, Sogang University, Seoul (Korea, Republic of)

    2015-04-15

    In this study, we report the synthesis of 2,3-dihydroxybenzaldehyde (catechol)-linked chitosan (cat-chitosan) and the preparation of its composite with carbon (cat-chitosan/carbon) to construct a catechol-modified electrode. The synthesis is similar to our previous work on hydroquinone–chitosan/carbon composite electrode. We synthesized catechol-linked chitosan polymer and prepared the its composite electrode with carbon. The catchitosan/carbon composite electrode shows a reversible confined redox behavior by the catechol functional group. The electrode catalyzes the oxidation of NADH. It has Cu{sup 2+} ion-binding capability and its binding constant 8.7 μM.

  1. Mesoporous carbon prepared from carbohydrate as hard template for hierarchical zeolites

    DEFF Research Database (Denmark)

    Egeblad, Kresten; Christensen, Claus H.

    2007-01-01

    A mesoporous carbon prepared from sucrose was successfully employed as a hard template to produce hierarchical silicalite-1, thus providing a very simple and inexpensive route to desirable zeolite catalysts from widely available raw materials. The porous carbon was prepared by hydrothermal...... treatment of a mixture of sucrose and ammonia followed by carbonization of the mixture in N-2 at high temperatures. The porous carbon produced by this method was subsequently applied as a hard template in the synthesis of mesoporous silicalite-1 and removed by combustion after synthesis. X-ray diffraction...... the porous carbon template as well as the mesoporous zeolite single-crystal material....

  2. Preparation of Fe-cored carbon nanomaterials from mountain pine beetle-killed pine wood

    Science.gov (United States)

    Sung Phil Mun; Zhiyong Cai; Jilei Zhang

    2015-01-01

    The mountain pine beetle-killed lodgepole pine (Pinus contorta) wood treated with iron (III) nitrate solution was used for the preparation of Fe-cored carbon nanomaterials (Fe-CNs) under various carbonization temperatures. The carbonization yield of Fe-treated sample (5% as Fe) was always 1–3% higher (after ash compensation) than that of the non-...

  3. Preparation of mesohollow and microporous carbon nanofiber and its application in cathode material for lithium–sulfur batteries

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Yuanhe; Gao, Mingxia, E-mail: gaomx@zju.edu.cn; Li, Xiang; Liu, Yongfeng; Pan, Hongge, E-mail: hgpan@zju.edu.cn

    2014-09-01

    Highlights: • Mesohollow and microporous carbon fibers were prepared via electrospinning and carbonization. • Sulfur (S) incorporated into the porous fibers by thermal heating in 60 wt.%, forming composite. • S fills fully in the micropores and partially in the mesohollows of the carbon fibers. • The composite shows high capacity and capacity retention as cathode material for Li–S batteries. • Mesohollow and microporous structure is effective in improving the property of S cathode. - Abstract: Mesohollow and microporous carbon nanofibers (MhMpCFs) were prepared by a coaxial electrospinning with polyacrylonitrile (PAN) and polymethylmethacrylate (PMMA) as outer and inner spinning solutions followed by a carbonization. The carbon fibers were thermal treated with sublimed sulfur to form S/MhMpCFs composite, which was used as cathode material for lithium–sulfur batteries. Electrochemical study shows that the S/MhMpCFs cathode material provides a maximum capacity of 815 mA h/g after several cycles of activation, and the capacity retains 715 mA h/g after 70 cycles, corresponding to a retention of 88%. The electrochemical property of the S/MhMpCFs composite is much superior than the S-incorporated solid carbon fibers prepared from electrospinning of single PAN. The mechanism of the enhanced electrochemical property of the S/MhMpCFs composite is discussed.

  4. Selection of pecan shell based activated carbons for removal of organic and inorganic impurities from simulated well-water

    Science.gov (United States)

    Activated carbons are a byproduct from pyrolysis and have value as a purifying agent. The effectiveness of activated carbons is dependent on feedstock selection and pyrolysis conditions that modify its surface properties. Therefore, pecan shell-based activated carbons (PSACs) were prepared by soakin...

  5. Preparation of Pt–Ru bimetallic catalyst supported on carbon ...

    Indian Academy of Sciences (India)

    Keywords. Carbon nanotubes; template synthesis; fuel cell catalyst; nanoparticles. Abstract. The template carbonization of polyphenyl acetylene yields hollow, uniform cylindrical carbon nanotubes with outer diameter almost equal to pore diameter of the template used. High resolution transmission electron microscopic ...

  6. The Transport Properties of Activated Carbon Fibers

    Science.gov (United States)

    di Vittorio, S. L.; Dresselhaus, M. S.; Endo, M.; Issi, J-P.; Piraux, L.

    1990-07-01

    The transport properties of activated isotropic pitch-based carbon fibers with surface area 1000 m{sup 2}/g have been investigated. We report preliminary results on the electrical conductivity, the magnetoresistance, the thermal conductivity and the thermopower of these fibers as a function of temperature. Comparisons are made to transport properties of other disordered carbons.

  7. Nano-sized Mn-doped activated carbon aerogel as electrode material for electrochemical capacitor: effect of activation conditions.

    Science.gov (United States)

    Lee, Yoon Jae; Park, Hai Woong; Park, Sunyoung; Song, In Kyu

    2012-07-01

    Carbon aerogel (CA) was prepared by a sol-gel polymerization of resorcinol and formaldehyde, and a series of activated carbon aerogels (ACA-KOH-X, X = 0, 0.3, 0.7, 1, and 2) were then prepared by a chemical activation using different amount of potassium hydroxide (X represented weight ratio of KOH with respect to CA). Specific capacitances of activated carbon aerogels were measured by cyclic voltammetry and galvanostatic charge/discharge methods in 6 M KOH electrolyte. Among the samples prepared, ACA-KOH-0.7 showed the highest specific capacitance (149 F/g). In order to combine excellent electrochemical performance of activated carbon aerogel with pseudocapacitive property of manganese oxide, 7 wt% Mn was doped on activated carbon aerogel (Mn/ACA-KOH-0.7) by an incipient wetness impregnation method. For comparison, 7 wt% Mn was also impregnated on carbon aerogel (Mn/ACA-KOH-0) by the same method. It was revealed that 7 wt% Mn-doped activated carbon aerogel (Mn/ACA-KOH-0.7) showed higher specific capacitance than 7 wt% Mn-doped carbon aerogel (Mn/ACA-KOH-0) (178 F/g vs. 98 F/g). The enhanced capacitance of Mn/ACA-KOH-0.7 was attributed to the outstanding electric properties of activated carbon aerogel as well as the faradaic redox reactions of manganese oxide.

  8. Production of activated carbon from a new precursor molasses by activation with sulphuric acid.

    Science.gov (United States)

    Legrouri, K; Khouya, E; Ezzine, M; Hannache, H; Denoyel, R; Pallier, R; Naslain, R

    2005-02-14

    Activated carbon has been prepared from molasses, a natural precursor of vegetable origin resulting from the sugar industry in Morocco. The preparation of the activated carbon from the molasses has been carried out by impregnation of the precursor with sulphuric acid, followed by carbonisation at varying conditions (temperature and gas coverage) in order to optimize preparation parameters. The influence of activation conditions was investigated by determination of adsorption capacity of methylene blue and iodine, the BET surface area, and the pore volume of the activated carbon were determined while the micropore volume was determined by the Dubinin-Radushkevich (DR) equation. The activated materials are mainly microporous and reveal the type I isotherm of the Brunauer classification for nitrogen adsorption. The activated carbons properties in this study were found for activation of the mixture (molasses/sulphuric acid) in steam at 750 degrees C. The samples obtained in this condition were highly microporous, with high surface area (> or =1200 m2/g) and the maximum adsorption capacity of methylene blue and iodine were 435 and 1430 mg/g, respectively.

  9. Preparation and enhanced photocatalytic activity of carbon nitride/titania(001 vs 101 facets)/reduced graphene oxide (g-C3N4/TiO2/rGO) hybrids under visible light

    Science.gov (United States)

    Huang, Meina; Yu, Jianhua; Hu, Qun; Su, Wenli; Fan, Minguang; Li, Bin; Dong, Lihui

    2016-12-01

    Herein, a novel photocatalyst, anatase TiO2 nanoparticles with both exposed (101) and (001) facets synchronously incorporated with g-C3N4 and graphene, was successfully prepared via a simple one-step solvothermal route. The morphology and structure of as-prepared composites were confirmed by X-ray diffraction (XRD), transmission electron microscopy (TEM), N2 adsorption, Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) and ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS). Efficiency of the prepared samples was investigated by monitoring the degradation of Methyl Orange (MO), Rhodamine B (RhB) and phenol under visible light irradiation. Improved photocatalytic activity in g-C3N4/TiO2/rGO is observed owing to higher specific surface area and enhanced visible light absorption capability. Most importantly, the in situ g-C3N4 and rGO doping might enhance the interaction among g-C3N4, TiO2 (001 vs 101) and rGO, which generates more synergistic heteroconjunctions in g-C3N4/TiO2/rGO facilitating a fast electron transfer at the interface among them. This synergistic approach could prove useful for the design and development of other visible light active photocatalysts with high chemical stability.

  10. Carbon composition with hierarchical porosity, and methods of preparation

    Science.gov (United States)

    Mayes, Richard T; Dai, Sheng

    2014-10-21

    A method for fabricating a porous carbon material possessing a hierarchical porosity, the method comprising subjecting a precursor composition to a curing step followed by a carbonization step, the precursor composition comprising: (i) a templating component comprised of a block copolymer, (ii) a phenolic component, (iii) a dione component in which carbonyl groups are adjacent, and (iv) an acidic component, wherein said carbonization step comprises heating the precursor composition at a carbonizing temperature for sufficient time to convert the precursor composition to a carbon material possessing a hierarchical porosity comprised of mesopores and macropores. Also described are the resulting hierarchical porous carbon material, a capacitive deionization device in which the porous carbon material is incorporated, as well as methods for desalinating water by use of said capacitive deionization device.

  11. Preparation of carbon nanotube-alginate nanocomposite gel for tissue engineering.

    Science.gov (United States)

    Kawaguchi, Minoru; Fukushima, Tadao; Hayakawa, Toru; Nakashima, Naotoshi; Inoue, Yusuke; Takeda, Shoji; Okamura, Kazuhiko; Taniguchi, Kunihisa

    2006-12-01

    A novel scaffold material based on an alginate hydrogel which contained carbon nanotubes (CNTs) was prepared, and its mechanical property and biocompatibility evaluated. Soluble CNTs were prepared with acid treatment and dispersed in sodium alginate solution as a cross-linker. After which, the mechanical property (elastic deformation), saline sorption, histological reaction, and cell viability of the resultant nanocomposite gel (CNT-Alg gel) were evaluated. The CNT-Alg gel showed faster gelling and higher mechanical strength than the conventional alginate gel. Saline sorption amount of freeze-dried CNT-Alg gel was equal to that of the alginate gel. In terms of histological evaluation and cell viability assay, CNT-Alg gel exhibited a mild inflammatory response and non-cytotoxicity. These results thus suggested that CNT-Alg gel could be useful as a scaffold material in tissue engineering with the sidewalls of CNTs acting as active sites for chemical functionalization.

  12. Processes for preparing carbon fibers using sulfur trioxide in a halogenated solvent

    Science.gov (United States)

    Patton, Jasson T.; Barton, Bryan E.; Bernius, Mark T.; Chen, Xiaoyun; Hukkanen, Eric J.; Rhoton, Christina A.; Lysenko, Zenon

    2015-12-29

    Disclosed here are processes for preparing carbonized polymers (preferably carbon fibers), comprising sulfonating a polymer with a sulfonating agent that comprises SO.sub.3 dissolved in a solvent to form a sulfonated polymer; treating the sulfonated polymer with a heated solvent, wherein the temperature of the solvent is at least 95.degree. C.; and carbonizing the resulting product by heating it to a temperature of 500-3000.degree. C. Carbon fibers made according to these methods are also disclosed herein.

  13. Carbon dioxide adsorption in chemically activated carbon from sewage sludge.

    Science.gov (United States)

    de Andrés, Juan Manuel; Orjales, Luis; Narros, Adolfo; de la Fuente, María del Mar; Encarnación Rodríguez, María

    2013-05-01

    In this work, sewage sludge was used as precursor in the production of activated carbon by means of chemical activation with KOH and NaOH. The sludge-based activated carbons were investigated for their gaseous adsorption characteristics using CO2 as adsorbate. Although both chemicals were effective in the development of the adsorption capacity, the best results were obtained with solid NaOH (SBA(T16)). Adsorption results were modeled according to the Langmuir and Freundlich models, with resulting CO2 adsorption capacities about 56 mg/g. The SBA(T16) was characterized for its surface and pore characteristics using continuous volumetric nitrogen gas adsorption and mercury porosimetry. The results informed about the mesoporous character of the SBA(T16) (average pore diameter of 56.5 angstroms). The Brunauer-Emmett-Teller (BET) surface area of the SBA(T16) was low (179 m2/g) in comparison with a commercial activated carbon (Airpel 10; 1020 m2/g) and was mainly composed of mesopores and macropores. On the other hand, the SBA(T16) adsorption capacity was higher than that of Airpel 10, which can be explained by the formation of basic surface sites in the SBA(T16) where CO2 experienced chemisorption. According to these results, it can be concluded that the use of sewage-sludge-based activated carbons is a promising option for the capture of CO2. Adsorption methods are one of the current ways to reduce CO2 emissions. Taking this into account, sewage-sludge-based activated carbons were produced to study their CO2 adsorption capacity. Specifically, chemical activation with KOH and NaOH of previously pyrolyzed sewage sludge was carried out. The results obtained show that even with a low BET surface area, the adsorption capacity of these materials was comparable to that of a commercial activated carbon. As a consequence, the use of sewage-sludge-based activated carbons is a promising option for the capture of CO2 and an interesting application for this waste.

  14. Monitoring by Control Technique - Activated Carbon Adsorber

    Science.gov (United States)

    Stationary source emissions monitoring is required to demonstrate that a source is meeting the requirements in Federal or state rules. This page is about Activated Carbon Adsorber control techniques used to reduce pollutant emissions.

  15. Bimodal activated carbons derived from resorcinol-formaldehyde cryogels

    Energy Technology Data Exchange (ETDEWEB)

    Szczurek, Andrzej; Amaral-Labat, Gisele; Fierro, Vanessa; Celzard, Alain [Institut Jean Lamour-UMR CNRS 7198, CNRS-Nancy-Universite-UPV-Metz, Departement Chimie et Physique des Solides et des Surfaces. ENSTIB, 27 rue Philippe Seguin, BP 1041, 88051 Epinal cedex 9 (France); Pizzi, Antonio, E-mail: Alain.Celzard@enstib.uhp-nancy.fr [ENSTIB-LERMAB, Nancy-Universite, 27 rue Philippe Seguin, BP1041, 88051 Epinal cedex 9 (France)

    2011-06-15

    Resorcinol-formaldehyde cryogels prepared at different dilution ratios have been activated with phosphoric acid at 450 deg. C and compared with their carbonaceous counterparts obtained by pyrolysis at 900 deg. C. Whereas the latter were, as expected, highly mesoporous carbons, the former cryogels had very different pore textures. Highly diluted cryogels allowed preparation of microporous materials with high surface areas, but activation of initially dense cryogels led to almost non-porous carbons, with much lower surface areas than those obtained by pyrolysis. The optimal acid concentration for activation, corresponding to stoichiometry between molecules of acid and hydroxyl groups, was 2 M l{sup -1}, and the acid-cryogel contact time also had an optimal value. Such optimization allowed us to achieve surface areas and micropore volumes among the highest ever obtained by activation with H{sub 3}PO{sub 4}, close to 2200 m{sup 2} g{sup -1} and 0.7 cm{sup 3} g{sup -1}, respectively. Activation of diluted cryogels with a lower acid concentration of 1.2 M l{sup -1} led to authentic bimodal activated carbons, having a surface area as high as 1780 m{sup 2} g{sup -1} and 0.6 cm{sup 3} g{sup -1} of microporous volume easily accessible through a widely developed macroporosity.

  16. Bimodal activated carbons derived from resorcinol-formaldehyde cryogels

    Directory of Open Access Journals (Sweden)

    Andrzej Szczurek, Gisele Amaral-Labat, Vanessa Fierro, Antonio Pizzi and Alain Celzard

    2011-01-01

    Full Text Available Resorcinol-formaldehyde cryogels prepared at different dilution ratios have been activated with phosphoric acid at 450 °C and compared with their carbonaceous counterparts obtained by pyrolysis at 900 °C. Whereas the latter were, as expected, highly mesoporous carbons, the former cryogels had very different pore textures. Highly diluted cryogels allowed preparation of microporous materials with high surface areas, but activation of initially dense cryogels led to almost non-porous carbons, with much lower surface areas than those obtained by pyrolysis. The optimal acid concentration for activation, corresponding to stoichiometry between molecules of acid and hydroxyl groups, was 2 M l−1, and the acid–cryogel contact time also had an optimal value. Such optimization allowed us to achieve surface areas and micropore volumes among the highest ever obtained by activation with H3PO4, close to 2200 m2 g−1 and 0.7 cm3 g−1, respectively. Activation of diluted cryogels with a lower acid concentration of 1.2 M l−1 led to authentic bimodal activated carbons, having a surface area as high as 1780 m2 g−1 and 0.6 cm3 g−1 of microporous volume easily accessible through a widely developed macroporosity.

  17. Preparation and mechanical properties of photo-crosslinked poly(trimethylene carbonate) and nano-hydroxyapatite composites

    NARCIS (Netherlands)

    Geven, Mike Alexander; Barbieri, D.; Yuan, Huipin; de Bruijn, Joost Dick; Grijpma, Dirk W.

    2015-01-01

    Composite materials of photo-crosslinked poly(trimethylene carbonate) and nanoscale hydroxyapatite were prepared and their mechanical characteristics for application as orbital floor implants were assessed. The composites were prepared by solvent casting poly(trimethylene carbonate) macromers with

  18. Optical and structural properties of carbon dots/TiO2 nanostructures prepared via DC arc discharge in liquid

    Science.gov (United States)

    Biazar, Nooshin; Poursalehi, Reza; Delavari, Hamid

    2018-01-01

    Synthesis and development of visible active catalysts is an important issue in photocatalytic applications of nanomaterials. TiO2 nanostructures coupled with carbon dots demonstrate a considerable photocatalytic activity in visible wavelengths. Extending optical absorption of a wide band gap semiconductor such as TiO2 with carbon dots is the origin of the visible activity of carbon dots modified semiconductor nanostructures. In addition, carbon dots exhibit high photostability, appropriate electron transport and chemical stability without considerable toxicity or environmental footprints. In this study, optical and structural properties of carbon dots/TiO2 nanostructures prepared via (direct current) DC arc discharge in liquid were investigated. Crystal structure, morphology and optical properties of the samples were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV-visible spectroscopy respectively. SEM images show formation of spherical nanoparticles with an average size of 27 nm. In comparison with pristine TiO2, optical transmission spectrum of carbon dots/TiO2 nanostructures demonstrates an absorption edge at longer wavelengths as well a high optical absorption in visible wavelengths which is significant for visible activity of nanostructures as a photocatalyst. Finally, these results can provide a flexible and versatile pathway for synthesis of carbon dots/oxide semiconductor nanostructures with an appropriate activity under visible light.

  19. Preparation and characterization of nanomaterials based on bifacial carbon nanotubes and iron oxides: Application in catalysis

    Directory of Open Access Journals (Sweden)

    Zafour-Hadj-Ziane A.

    2013-09-01

    Full Text Available The application of magnetic particles technology for the development of new nanomaterials has received considerable attention in recent years. In this context, the objective of this study is firstly, to prepare new catalytic materials that gather the strong adsorption capacities of carbon nanotubes and magnetic properties of iron, it concerns nanocomposites based on a mixture of carbon nanotubes in a very small amounts and iron oxide. Secondly we want to appear their capacities in catalytic oxidation reactions of phenol. Synthesis under the optimal conditions was carried out at different pH. And the characterization of this new nanomaterial reveals a good specific surface area BET, the identification of carbon nanotubes within the matrix was performed by infrared spectroscopy and transmission electron microscopy. The use of this new material as a catalytic support in catalytic oxidation reactions of phenol indicates the high selectivity of this latter and a yield better than this obtained with iron oxide supported by activated carbon. The good catalyst regeneration of the new catalysis and the improvement in their properties are the interesting parameters for the new type nanomaterials.

  20. The roles and electrochemical characterizations of activated carbon in zinc air battery cathodes

    Energy Technology Data Exchange (ETDEWEB)

    Eom, Seung-Wook; Lee, Chang-Woo; Yun, Mun-Soo [Battery Research Group, Korea Electrotechnology Research Institute (KERI), P.O. Box 20, Changwon 641-600 (Korea, Republic of); Sun, Yang-Kook [Department of Chemical Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of)

    2006-12-01

    We prepared cathodes with various types of activated carbon and measured the cathodes' electrochemical performance according to the kind of activated carbon. Activated carbon supplies airflow channels and reaction sites in the cathode of zinc air batteries. When we use activated carbon with a high specific surface area as the cathode's catalyst substrate, we expect high electrochemical performance because this type of carbon provides more air flow channels and reaction sites. We focused on investigating the relationship between the cathode's pore structure and its electrochemical characterizations. We also studied the effects of the various activated carbon materials on the zinc air batteries' performance. Increasing the macropores or mesopores in the activated carbon resulted in achieving more power from the battery. (author)

  1. Preparation and characterization of carbonic anhydrase-conjugated liposomes for catalytic synthesis of calcium carbonate particles.

    Science.gov (United States)

    Maeshima, Keisuke; Yoshimoto, Makoto

    2017-10-01

    The biomimetic approach using immobilized enzymes is useful for the synthesis of structurally defined inorganic materials. In this work, carbonic anhydrase (CA) from bovine erythrocytes was covalently conjugated at 25°C to the liposomes composed of 15mol% 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine-N-(glutaryl) (NG-POPE), and the zwitterionic and anionic phospholipids with the same acyl chains as NG-POPE. For the conjugation, the carboxyl groups of liposomal NG-POPE were activated with 11mM 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and 4.6mM N-hydroxysulfosuccinimide (sulfo-NHS). The carbonic anhydrase-conjugated liposomes (CALs) with the mean hydrodynamic diameter of 149nm showed the esterase activity corresponding to on average 5.5×102 free CA molecules per liposome. On the other hand, the intrinsic fluorescence and absorbance measurements consistently revealed that on average 1.4×103 CA molecules were conjugated to a liposome, suggesting that the molecular orientation of enzyme affected its activity. The formation of calcium carbonate particles was significantly accelerated by the CALs ([lipid]=50μ M) in the 0.3M Tris solution at 10-40°C with dissolved CO2 (≈17mM) and CaCl2 (46mM). The anionic CALs were adsorbed with calcium as revealed with the ζ-potential measurements. The CAL system offered the calcium-rich colloidal interface where the bicarbonate ions were catalytically produced by the liposome-conjugated CA molecules. The CALs also functioned in the external loop airlift bubble column operated with a model flue gas (10vol/vo% CO2), yielding partly agglomerated calcium carbonate particles as observed with the scanning electron microscopy (SEM). Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Orthophosphoric Acid Activated Babul Seed Carbon as an Adsorbent for the Removal of Methylene Blue

    Directory of Open Access Journals (Sweden)

    M. Sujatha

    2008-01-01

    Full Text Available An Experimental and theoretical study has been conducted on the adsorption of methylene blue dye using activated carbon prepared from babul seed by chemical activation with orthophosphoric acid. BET surface area of the activated carbon was determined as 1060 m2/g. Adsorption kinetics, equilibrium and thermodynamics were investigated as a function of initial dye concentration, temperature and pH. First order Lagergren, pseudo-second order and Elovich kinetic models were used to test the adsorption kinetics. Results were analyzed by the Langmuir, Freundlich and Temkin isotherm models. Based on regression coefficient, the equilibrium data found fitted well to the Langmuir equilibrium model than other models. The characteristics of the prepared activated carbon were found comparable to the commercial activated carbon. It is found that the babul seed activated carbon is very effective for the removal of colouring matter.

  3. Preparation and enhanced photocatalytic activity of carbon nitride/titania(001 vs 101 facets)/reduced graphene oxide (g-C{sub 3}N{sub 4}/TiO{sub 2}/rGO) hybrids under visible light

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Meina [School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004 (China); Yu, Jianhua [School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004 (China); Tobacoo Monopoly Bureau, Guangxi Zhuang Autonomous Rejion, Nanning, 530022 (China); Hu, Qun; Su, Wenli [School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004 (China); Fan, Minguang, E-mail: fanmg@gxu.edu.cn [School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004 (China); Guangxi Key Laboratory Petrochemical Rescource Processing and Process Intensification Technology, Nanning 530004 (China); Li, Bin [School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004 (China); Dong, Lihui, E-mail: donglihui2005@126.com [School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004 (China)

    2016-12-15

    Graphical abstract: Schematic for the enhanced photocatalytic activity of CN/T/rGO hybrids upon visible light irradiation. - Highlights: • g-C{sub 3}N{sub 4}/TiO{sub 2}(001 vs 101 Facets)/rGO were prepared via one-step solvothermal route. • Performance evaluation was carried out under visible light irradiation. • Samples show excellent photocatalytic activities and stablity. • A possible photocatalytic mechanism is proposed. • The structural effects of g-C{sub 3}N{sub 4}/TiO{sub 2}/rGO explain excellent performance. - Abstract: Herein, a novel photocatalyst, anatase TiO{sub 2} nanoparticles with both exposed (101) and (001) facets synchronously incorporated with g-C{sub 3}N{sub 4} and graphene, was successfully prepared via a simple one-step solvothermal route. The morphology and structure of as-prepared composites were confirmed by X-ray diffraction (XRD), transmission electron microscopy (TEM), N{sub 2} adsorption, Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) and ultraviolet-visible diffuse reflectance spectroscopy (UV–vis DRS). Efficiency of the prepared samples was investigated by monitoring the degradation of Methyl Orange (MO), Rhodamine B (RhB) and phenol under visible light irradiation. Improved photocatalytic activity in g-C{sub 3}N{sub 4}/TiO{sub 2}/rGO is observed owing to higher specific surface area and enhanced visible light absorption capability. Most importantly, the in situ g-C{sub 3}N{sub 4} and rGO doping might enhance the interaction among g-C{sub 3}N{sub 4}, TiO{sub 2} (001 vs 101) and rGO, which generates more synergistic heteroconjunctions in g-C{sub 3}N{sub 4}/TiO{sub 2}/rGO facilitating a fast electron transfer at the interface among them. This synergistic approach could prove useful for the design and development of other visible light active photocatalysts with high chemical stability.

  4. Antimicrobial Activity of Carbon-Based Nanoparticles

    Directory of Open Access Journals (Sweden)

    Solmaz Maleki Dizaj

    2015-03-01

    Full Text Available Due to the vast and inappropriate use of the antibiotics, microorganisms have begun to develop resistance to the commonly used antimicrobial agents. So therefore, development of the new and effective antimicrobial agents seems to be necessary. According to some recent reports, carbon-based nanomaterials such as fullerenes, carbon nanotubes (CNTs (especially single-walled carbon nanotubes (SWCNTs and graphene oxide (GO nanoparticles show potent antimicrobial properties. In present review, we have briefly summarized the antimicrobial activity of carbon-based nanoparticles together with their mechanism of action. Reviewed literature show that the size of carbon nanoparticles plays an important role in the inactivation of the microorganisms. As major mechanism, direct contact of microorganisms with carbon nanostructures seriously affects their cellular membrane integrity, metabolic processes and morphology. The antimicrobial activity of carbon-based nanostructures may interestingly be investigated in the near future owing to their high surface/volume ratio, large inner volume and other unique chemical and physical properties. In addition, application of functionalized carbon nanomaterials as carriers for the ordinary antibiotics possibly will decrease the associated resistance, enhance their bioavailability and provide their targeted delivery.

  5. Preparation of carbon nanotubes with different morphology by microwave plasma enhanced chemical vapour deposition

    Energy Technology Data Exchange (ETDEWEB)

    Duraia, El-Shazly M. [Suez Canal University, Faculty of Science, Physics Department, Ismailia (Egypt); Al-Farabi Kazakh National University, 71 Al-Farabi av., 050038 Almaty (Kazakhstan); Institute of Physics and Technology, Ibragimov Street 11, 050032 Almaty (Kazakhstan); Mansurov, Zulkhair [Al-Farabi Kazakh National University, 71 Al-Farabi av., 050038 Almaty (Kazakhstan); Tokmoldin, S.Zh. [Institute of Physics and Technology, Ibragimov Street 11, 050032 Almaty (Kazakhstan)

    2010-04-15

    In this work we present a part of our results about the preparation of carbon nanotube with different morphologies by using microwave plasma enhanced chemical vapour deposition MPECVD. Well aligned, curly, carbon nanosheets, coiled carbon sheets and carbon microcoils have been prepared. We have investigated the effect of the different growth condition parameters such as the growth temperature, pressure and the hydrogen to methane flow rate ratio on the morphology of the carbon nanotubes. The results showed that there is a great dependence of the morphology of carbon nanotubes on these parameters. The yield of the carbon microcoils was high when the growth temperature was 700 C. There is a linear relation between the growth rate and the methane to hydrogen ratio. The effect of the gas pressure on the CNTs was also studied. Our samples were investigated by scanning electron microscope and Raman spectroscopy (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  6. Scale-up activation of carbon fibres for hydrogen storage

    Energy Technology Data Exchange (ETDEWEB)

    Kunowsky, M.; Marco-Lozar, J.P.; Cazorla-Amoros, D.; Linares-Solano, A. [Grupo de Materiales Carbonosos y Medio Ambiente, Departamento de Quimica Inorganica, Universidad de Alicante, Ap. 99, E-03080 Alicante (Spain)

    2010-03-15

    In a previous study, we investigated, at a laboratory scale, the chemical activation of two different carbon fibres (CF), their porosity characterization, and their optimization for hydrogen storage. In the present work, this study is extended to: (i) a larger range of KOH activated carbon fibres, (ii) a larger range of hydrogen adsorption measurements at different temperatures and pressures (i.e. at room temperature, up to 20 MPa, and at 77 K, up to 4 MPa), and (iii) a scaling-up activation approach in which the obtained activated carbon fibres (ACF) are compared with those from laboratory-scale activation. The prepared samples cover a large range of porosities, which is found to govern their ability for hydrogen adsorption. The hydrogen uptake capacities of all the prepared samples have been analysed both in volumetric and in gravimetric bases. Thus, maximum adsorption capacities of around 5 wt% are obtained at 77 K, and 1.1 wt% at room temperature, respectively. The packing densities of the materials have been measured, turning out to play an important role in order to estimate the total storage capacity of a tank volume. Maximum values of 17.4 g l{sup -1} at 298 K, and 38.6 g l{sup -1} at 77 K were obtained. (author)

  7. Carbon nitride transparent counter electrode prepared by magnetron sputtering for a dye-sensitized solar cell

    Directory of Open Access Journals (Sweden)

    Chaoyu Wu

    2017-07-01

    Full Text Available Carbon nitride (CNx films supported on fluorine-doped tin oxide (FTO glass are prepared by radio frequency magnetron sputtering, in which the film thicknesses are 90–100 nm, and the element components in the CNx films are in the range of x = 0.15–0.25. The as-prepared CNx is for the first time used as counter electrode for dye-sensitized solar cells (DSSCs, and show a preparation-temperature dependent electrochemical performance. X-ray photoelectron spectroscopy (XPS demonstrates that there is a higher proportion of sp2 CC and sp3 CN hybridized bonds in CNx-500 (the sample treated at 500 °C than in CNx-RT (the sample without a heat treatment. It is proposed that the sp2 CC and sp3 C–N hybridized bonds in the CNx films are helpful for improving the electrocatalytic activities in DSSCs. Meanwhile, Raman spectra also prove that CNx-500 has a relatively high graphitization level that means an increasing electrical conductivity. This further explains why the sample after the heat treatment has a higher electrochemical performance in DSSCs. In addition, the as-prepared CNx counter electrodes have a good light transmittance in the visible light region. The results are meaningful for developing low-cost metal-free transparent counter electrodes for DSSCs. Keywords: Solar cells, Counter electrodes, Carbon nitride, Electrocatalysis, Magnetron sputtering

  8. Preparation and Characterization of Mesophase Pitch via Co-Carbonization of Waste Polyethylene]Petroleum Pitch

    National Research Council Canada - National Science Library

    Youliang Cheng Lu Yang Tao Luo Changqing Fang Jian Su Jian Hui

    2015-01-01

    The low-cost petroleum pitch and waste polyethylene (WPE) were used as raw materials to prepare the mesophase pitch by co-carbonization method and the forming mechanization of mesophase pitch was also investigated...

  9. Activated carbons from KOH-activation of argan (Argania spinosa) seed shells as supercapacitor electrodes.

    Science.gov (United States)

    Elmouwahidi, Abdelhakim; Zapata-Benabithe, Zulamita; Carrasco-Marín, Francisco; Moreno-Castilla, Carlos

    2012-05-01

    Activated carbons were prepared by KOH-activation of argan seed shells (ASS). The activated carbon with the largest surface area and most developed porosity was superficially treated to introduce oxygen and nitrogen functionalities. Activated carbons with a surface area of around 2100 m(2)/g were obtained. Electrochemical measurements were carried out with a three-electrode cell using 1M H(2)SO(4) as electrolyte and Ag/AgCl as reference electrode. The O-rich activated carbon showed the lowest capacitance (259 F/g at 125 mA/g) and the lowest capacity retention (52% at 1A/g), due to surface carboxyl groups hindering electrolyte diffusion into the pores. Conversely, the N-rich activated carbon showed the highest capacitance (355 F/g at 125 mA/g) with the highest retention (93% at 1A/g), due to its well-developed micro-mesoporosity and the pseudocapacitance effects of N functionalities. This capacitance performance was among the highest reported for other activated carbons from a large variety of biomass precursors. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Production of activated carbons from almond shell

    Energy Technology Data Exchange (ETDEWEB)

    Nabais, Joao M. Valente; Laginhas, Carlos Eduardo C.; Carrott, P.J.M.; Ribeiro Carrott, M.M.L. [Evora Univ. (Portugal). Centro de Quimica de Evora

    2011-02-15

    The production of activated carbons from almond shell, using physical activation by CO{sub 2} is reported in this work. The used method has produced activated carbons with apparent BET surface areas and micropore volume as high as 1138 m{sup 2} g{sup -1} and 0.49 cm{sup 3} g{sup -1}, respectively. The activated carbons produced have essentially primary micropores and only a small volume of wider micropores. By FTIR analysis it was possible to identify, in the surface of the activated carbons, several functional groups, namely hydroxyls (free and phenol), ethers, esters, lactones, pyrones and Si-H bonds. By the analysis of the XRD patterns it was possible to calculate the microcrystallites dimensions with height between 1.178 and 1.881 nm and width between 3.106 and 5.917 nm. From the XRD it was also possible to identify the presence of traces of inorganic heteroatoms such as Si, Pb, K, Fe and P. All activated carbons showed basic characteristics with point of zero charge between 9.42 and 10.43. (author)

  11. Imobilização da pancreatina em carvão ativado e em alumina para o preparo de hidrolisados de soro de leite = Immobilization of pancreatin in activated carbon and in alumina for preparing whey hydrolysates

    Directory of Open Access Journals (Sweden)

    Viviane Dias Medeiros Silva

    2005-07-01

    Full Text Available Tendo como objetivo a redução de custos do processo de fabricação dehidrolisados protéicos, estudou-se neste trabalho a imobilização da pancreatina, por adsorção, em carvão ativado e em alumina. Para isso, foram testadas diferentes condições de imobilização (30, 60 e 90min a 25°C, e 12h a 5°C. Para verificar a taxa de imobilização, determinou-se indiretamente a enzima não adsorvida nos suportes. Ao se utilizar o carvão ativado, não foi observada diferença significativa entre as condições testadas, tendo-se obtido 100% de imobilização enzimática. Para a alumina, a melhor condição foi a de 90min, na qual se obteve 37% de imobilização. A medida do grau de exposição da fenilalanina, pela espectrofotometria derivada segunda, foi empregada para a determinação da estabilidade operacional da enzima, tendo sido mostrado que a imobilização em carvão ativado e emalumina permitiu a reutilização da pancreatina por até 5 vezes e 2 vezes, respectivamente.Immobilization of pancreatin in activated carbon and in alumina was studied for producing protein hydrolysates, in order to reduce the process costs. Different immobilization conditions were tested (30, 60 and 90min at 25°C, and 12h at 5°C. For estimating the immobilization rate the amount of the non-adsorbed enzyme on the supports was indirectly determined. When activated carbon was used, no significant difference was observed among the tested conditions, obtaining 100% of enzymatic immobilization. In case of alumina, the best condition showed to be the 90min treatment which produced 37% of immobilization. The evaluation of the degree of exposition ofphenylalanine, by second derivative spectrophotometry, was used for the determination of the enzyme operational stability, and showed that the immobilization in activated carbon and in alumina allowed the reusability of the pancreatin for 5 times and 2 times,respectively.

  12. 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...

  13. Activated coconut shell charcoal carbon using chemical-physical activation

    Science.gov (United States)

    Budi, Esmar; Umiatin, Nasbey, Hadi; Bintoro, Ridho Akbar; Wulandari, Futri; Erlina

    2016-02-01

    The use of activated carbon from natural material such as coconut shell charcoal as metal absorbance of the wastewater is a new trend. The activation of coconut shell charcoal carbon by using chemical-physical activation has been investigated. Coconut shell was pyrolized in kiln at temperature about 75 - 150 °C for about 6 hours in producing charcoal. The charcoal as the sample was shieved into milimeter sized granule particle and chemically activated by immersing in various concentration of HCl, H3PO4, KOH and NaOH solutions. The samples then was physically activated using horizontal furnace at 400°C for 1 hours in argon gas environment with flow rate of 200 kg/m3. The surface morphology and carbon content of activated carbon were characterized by using SEM/EDS. The result shows that the pores of activated carbon are openned wider as the chemical activator concentration is increased due to an excessive chemical attack. However, the pores tend to be closed as further increasing in chemical activator concentration due to carbon collapsing.

  14. Formation of continuous activated carbon fibers for barrier fabrics

    Science.gov (United States)

    Liang, Ying

    1997-08-01

    Commercial protective suits made of active carbon granules or nonwoven fabrics are heavy, have low moisture vapor transport rate, and are uncomfortable. Inherent problems due to construction of barrier fabrics lead to severe heat stress when worn for even short time in warm environments. One proposed method to eliminate these problems is to facilitate the construction of a fabric made of continuous activated carbon fibers (CACF). This study is directed toward investigating the possibility of developing CAFC from two precursors: aramid and fibrillated PAN fiber. It was shown in this study that Kevlar-29 fibers could be quickly carbonized and activated to CACF with high adsorptivity and relatively low weight loss. CACF with high surface area (>500 msp2/g) and reasonable tenacity (≈1g/denier) were successfully prepared from Kevlar fibers through a three-step process: pretreatment, carbonization, and activation. X-ray diffraction, Fourier Transform Infrared Spectroscopy (FTIR), and thermal analysis were conducted to understand the evolution of physical and chemical properties during pretreatment. The influence of temperature, heating rate, and pyrolysis environment on the thermal behavior was determined by DSC and TGA/DTA and used as an indicator for optimizing the pyrolysis conditions. Surface analysis by nitrogen isotherms indicated that the resultant fibers had micropores and mesopores on the surface of CACF. This was also inferred by studies on the surface morphology through Scanning Electron Microscopy (SEM) and Scanning Tunneling Microscopy (STM). An investigation of the surface chemical structure by X-ray photoelectron spectroscopy (XPS) before and after activation and elemental analysis confirmed that adsorption of Kevlar based CACF mainly arises due to the physisorption instead of chemisorption. A multistep stabilization along with carbonization and activation was used to prepare active carbon fiber from fibrillated PAN fiber. The resultant fiber retained

  15. Various conformations of carbon nanocoils prepared by supported Ni-Fe/molecular sieve catalyst.

    Science.gov (United States)

    Yang, Shaoming; Chen, Xiuqin; Takeuchi, K; Motojima, Seiji

    2006-01-01

    The carbon nanocoils with various kinds of conformations were prepared by the catalytic pyrolysis of acetylene using the Ni metal catalyst supported on molecular Sieves which was prepared using Fe-containing kaolin as the raw material. There are four kinds of carbon nanocoils conformations produced by this catalyst. The influences of reaction temperature and gas conditions on the conformations of the nanocoils were investigated and the reasons of forming nano-size coils were discussed by comparison with pure Ni metal catalyst.

  16. Enhanced adsorption of perfluorooctane sulfonate and perfluorooctanoate by bamboo-derived granular activated carbon.

    Science.gov (United States)

    Deng, Shubo; Nie, Yao; Du, Ziwen; Huang, Qian; Meng, Pingping; Wang, Bin; Huang, Jun; Yu, Gang

    2015-01-23

    A bamboo-derived granular activated carbon with large pores was successfully prepared by KOH activation, and used to remove perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) from aqueous solution. The granular activated carbon prepared at the KOH/C mass ratio of 4 and activation temperature of 900°C had fast and high adsorption for PFOS and PFOA. Their adsorption equilibrium was achieved within 24h, which was attributed to their fast diffusion in the micron-sized pores of activated carbon. This granular activated carbon exhibited the maximum adsorbed amount of 2.32mmol/g for PFOS and 1.15mmol/g for PFOA at pH 5.0, much higher than other granular and powdered activated carbons reported. The activated carbon prepared under the severe activation condition contained many enlarged pores, favorable for the adsorption of PFOS and PFOA. In addition, the spent activated carbon was hardly regenerated in NaOH/NaCl solution, while the regeneration efficiency was significantly enhanced in hot water and methanol/ethanol solution, indicating that hydrophobic interaction was mainly responsible for the adsorption. The regeneration percent was up to 98% using 50% ethanol solution at 45°C. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Activated carbon derived from rice husk by NaOH activation and its application in supercapacitor

    Directory of Open Access Journals (Sweden)

    Khu Le Van

    2014-06-01

    Full Text Available Four activated carbon (AC samples prepared from rice husk under different activation temperatures have been characterized by N2 adsorption–desorption isotherms, thermogravimetric analysis (TGA–DTA, Fourier transform infrared spectroscopy (FTIR and scanning electron microscopy (SEM. The specific surface area of AC sample reached 2681 m2 g−1 under activation temperature of 800 °C. The AC samples were then tested as electrode material; the specific capacitance of the as-prepared activated carbon electrode was found to be 172.3 F g−1 using cyclic voltammetry at a scan rate of 5 mV s−1 and 198.4 F g−1 at current density 1000 mA g−1 in the charge/discharge mode.

  18. Study of the interactions bacteria - phenanthrene - activated carbon for the preparation of a permeable reactive barrier; Etude des interactions bacteries - phenanthrene - charbon en vue de l'elaboration d'une barriere permeable reactive

    Energy Technology Data Exchange (ETDEWEB)

    Leglize, P.

    2004-12-01

    Permeable Reactive Barrier (PRB) is a new way for the remediation of contaminated groundwater, but up to now Polycyclic Aromatic Hydrocarbons (PAHs) were rarely considered. We investigated PAH - bacteria - materials interactions in order to validate the feasibility of PRB for PAH contamination. PHE Adsorption/desorption kinetics onto different materials, activated carbons (CA), pozzolana (Pz) and pozzolana coated with heavy fuel (PzF), were investigated. PHE biodegradation were performed on batch using PAH degrading bacteria and the PRB materials. CA was a good media for PRB process: Phenanthrene sorption capacity is 100 to 10000 fold higher than PzF and Pz. Phenanthrene mineralization with CA was higher than without material. Bacterial properties affected PHE biodegradation. Bio-film production improved PHE biodegradation by PAH degrading bacteria. Column studies showed that inoculation of the column improved its efficiency: adsorbed PHE degradation and increased retardation of PHE. (author)

  19. Converting Poultry Litter into Activated Carbon

    Science.gov (United States)

    Disposal of animal manure is one of the biggest problems facing agriculture today. Now new technology has been designed to covert manure into environmentally friendly and highly valued activated carbon. When pelletized and activated under specific conditions, the litter becomes a highly porous mat...

  20. Preparation of carbon nanotube bioconjugates for biomedical applications

    OpenAIRE

    Liu, Zhuang; Tabakman, Scott M; Chen, Zhuo; Dai, Hongjie

    2009-01-01

    Biomedical applications of carbon nanotubes have attracted much attention in recent years. Here, we summarize our previously developed protocols for functionalization and bioconjugation of single-walled carbon nanotubes (SWNTs) for various biomedical applications including biological imaging; using nanotubes as Raman, photoluminescence and photoacoustic labels; sensing using nanotubes as Raman tags and drug delivery. Sonication of SWNTs in solutions of phospholipid-polyethylene glycol (PL-PEG...

  1. The effect of the use of 2% chlorhexidine gel in post-space preparation on carbon fiber post retention.

    Science.gov (United States)

    da Silva, Ricardo Souza; de Almeida Antunes, Rossana Pereira; Ferraz, Caio Cézar Randi; Orsi, Iara Augusta

    2005-03-01

    Evaluate the bond strength of a resin cement used to lute carbon fiber posts, when drills and 4 different substances were used for the post-space preparation. Forty human canines were treated endodontically, and had a 10-mm length post space preparation. Four different substances were used with the drills: G1 -saline, G2 -2% chlorhexidine gel, G3 -EDTA/NaOCl, and G4 -xylene. Carbon fiber posts (C-Post) were cemented with Allbond2 and Hi-X. Then, the posts were dislodged by tensional forces. The groups of chlrohexidine (G2) and xylene (G4) obtained superior average values of bond strength at the 5% significance level (Parametric analyzes ANOVA/Tukey/Scheffe) differing statistically from the other groups. There was no statistical significant difference between groups 2 and 4. Xylene and chlorhexidine gel are good substances for the post-space preparation but the second has the advantage of antimicrobial activity and low toxicity.

  2. Preparation and characterization of carbon-enriched coal fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Rubio, B.; Izquierdo, M.T.; Mayoral, M.C.; Bona, M.T.; Martinez-Tarazona, R.M. [CSIC, Zaragoza (Spain)

    2008-09-15

    Carbon-enriched fractions have been obtained from two coal fly ash (FA) samples. The FA came from two pulverized-coal fired power stations (Lada and Escucha, Spain) and were collected from baghouse filters. Sieving was used to obtain carbon-enriched fractions, which were further subjected to two beneficiation processes: acid demineralization using HCl and HF, and oil agglomeration using soya oil-water. Yield in weight after sieving, unburned carbon content, and several physicochemical characteristics, of the obtained fractions were used to compare the performance of the beneficiation methods. Low carbon concentration was obtained by sieving. particularly in the case of Escucha FA. However, after acid demineralization or oil agglomeration, fractions containing unburned carbon in a range of 63% to 68% were obtained. These fractions showed differences in mineral phase composition and distribution depending on the FA and oil the beneficiation method used. The textural properties of the obtained fractions varied as a function of their carbon content and the beneficiation method used. However, no significant differences in morphology of the carbonaceous particles were found

  3. Preparation of Ultra-fine Calcium Carbonate by a Solvent-free ...

    African Journals Online (AJOL)

    NJD

    2008-09-19

    Sep 19, 2008 ... circulating carbonation7 and absorption spraying.8 In this paper, we report a new solid-state reaction method using solvent-free conditions at low temperature and by application of a super- sonic airflow for the preparation of ultra-fine calcium carbonate. This new method could be extended to large-scale ...

  4. Carbon-coated copper nanoparticles prepared by detonation method and their thermocatalysis on ammonium perchlorate

    Directory of Open Access Journals (Sweden)

    Chongwei An

    2017-03-01

    Full Text Available Carbon-coated copper nanoparticles (CCNPs were prepared by initiating a high-density charge pressed with a mixture of microcrystalline wax, hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX, and copper nitrate hydrate (Cu(NO32·3H2O in an explosion vessel filled with nitrogen gas. The detonation products were characterized by transmission electron microcopy (TEM, high resolution transmission electron microcopy (HRTEM, energy dispersive X-ray spectroscopy (EDX, X-ray diffraction (XRD, and Raman spectroscopy. The effects of CCNPs on thermal decomposition of ammonium perchlorate (AP were also investigated by differential scanning calorimeter (DSC. Results indicated that the detonation products were spherical, 25-40 nm in size, and had an apparent core-shell structure. In this structure, the carbon shell was 3-5 nm thick and mainly composed of graphite, C8 (a kind of carbyne, and amorphous carbon. When 5 wt.% CCNPs was mixed with 95 wt.% AP, the high-temperature decomposition peak of AP decreased by 95.97, 96.99, and 96.69 °Cat heating rates of 5, 10, and 20 °C/min, respectively. Moreover, CCNPs decreased the activation energy of AP as calculated through Kissinger’s method by 25%, which indicated outstanding catalysis for the thermal decomposition of AP.

  5. Preparation of Multiwalled Carbon Nanotube-Poly (4-Styrenesulfonic Acid Aqueous Dispersion for Dopamine Sensing

    Directory of Open Access Journals (Sweden)

    Aihua LIU

    2006-12-01

    Full Text Available A simple and facile method for the non-covalent functionalization of multi-walled carbon nanotubes (MWNTs using poly(4-styrenesulfonic acid (PSS is proposed. The resulting PSS-MWNTs dispersion is readily soluble in water and can be left to stand for 2 weeks at room temperature, no phase separation with aggregation of nanotubes at the bottom of the vials was observed. The as-prepared PSS-MWNTs dispersions could facilitate the processing of the nanotubes into composites with high nanotube loading. The PSS-MWNTs complex shows high electrocatalytic activity to the oxidation of neutrontransmitter of dopamine, suggesting that the coating of PSS onto carbon nanotubes surface without destroying the electronic structures of the pristine carbon nanotubes; therefore, the unique properties including the catalytic property of the nanotubes retained. It is envisioned that the PSS-MWNTs aqueous dispersions may find possible applications in the development of biosensors, bioelectronics, separation and environment protection as well as other biological events where water-based environment is required.

  6. Carbon-coated copper nanoparticles prepared by detonation method and their thermocatalysis on ammonium perchlorate

    Science.gov (United States)

    An, Chongwei; Ding, Penghui; Ye, Baoyun; Geng, Xiaoheng; Wang, Jingyu

    2017-03-01

    Carbon-coated copper nanoparticles (CCNPs) were prepared by initiating a high-density charge pressed with a mixture of microcrystalline wax, hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), and copper nitrate hydrate (Cu(NO3)2.3H2O) in an explosion vessel filled with nitrogen gas. The detonation products were characterized by transmission electron microcopy (TEM), high resolution transmission electron microcopy (HRTEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and Raman spectroscopy. The effects of CCNPs on thermal decomposition of ammonium perchlorate (AP) were also investigated by differential scanning calorimeter (DSC). Results indicated that the detonation products were spherical, 25-40 nm in size, and had an apparent core-shell structure. In this structure, the carbon shell was 3-5 nm thick and mainly composed of graphite, C8 (a kind of carbyne), and amorphous carbon. When 5 wt.% CCNPs was mixed with 95 wt.% AP, the high-temperature decomposition peak of AP decreased by 95.97, 96.99, and 96.69 °Cat heating rates of 5, 10, and 20 °C/min, respectively. Moreover, CCNPs decreased the activation energy of AP as calculated through Kissinger's method by 25%, which indicated outstanding catalysis for the thermal decomposition of AP.

  7. Preparation and Electrocapacitive Properties of Hierarchical Porous Carbons Based on Loofah Sponge

    Directory of Open Access Journals (Sweden)

    Zichao Li

    2016-11-01

    Full Text Available Four porous carbon samples denoted as LSC-1, LSC-2, LCS-3, and LSC-4 were prepared by carbonization of loofah sponge pretreated by ZnCl2 activation, immersion in N,N-dimethylformamide (DMF, DMF-assisted solvothermal and melamine-assisted hydrothermal processes, and the specific surface areas were 1007, 799, 773, and 538 m2·g−1 with mainly micropores, respectively. Electrocapacitive properties of four porous carbon-based electrodes were investigated with cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy in symmetric supercapacitors. All the cyclic voltammetries of four types of supercapacitors showed a rectangular shape, even under a high scan rate of 500 mV·s−1. The capacitances of LSC-1, LSC-2, LSC-3, and LSC-4 were 107.4, 92.5, 60.3, and 82.3 F·g−1 at the current density of 0.1 A·g−1, respectively, and LSC-1 displayed the excellent capacitance retention of about 81.3% with a current density up to 5 A·g−1. All supercapacitors showed excellent electrochemical stability, and the LSC-1-based supercapacitor showed a cycle stability with 92.6% capacitance retention after 5000 cycles at 1 A·g−1. The structure–property relationship of LSC samples is discussed and analyzed on the basis of the experimental data.

  8. Activated carbon derived from carbon residue from biomass gasification and its application for dye adsorption: Kinetics, isotherms and thermodynamic studies.

    Science.gov (United States)

    Maneerung, Thawatchai; Liew, Johan; Dai, Yanjun; Kawi, Sibudjing; Chong, Clive; Wang, Chi-Hwa

    2016-01-01

    In this work, activated carbon (AC) as an effective and low-cost adsorbent was successfully prepared from carbon residue (or char, one of the by-products from woody biomass gasification) via physical activation. The surface area of char was significantly increased from 172.24 to 776.46m(2)/g after steam activation at 900°C. The obtained activated carbons were then employed for the adsorption of dye (Rhodamine B) and it was found that activated carbon obtained from steam activation exhibited the highest adsorption capability, which is mainly attributed to the higher surface area and the abundance of hydroxyl (-OH) and carboxyl (-COOH) groups on the activated carbon surface. Moreover, it was also found that the adsorption capability significantly increased under the basic condition, which can be attributed to the increased electrostatic interaction between the deprotonated (negatively charged) activated carbon and dye molecules. Furthermore, the equilibrium data were fitted into different adsorption isotherms and found to fit well with Langmuir model (indicating that dye molecules form monolayer coverage on activated carbon) with a maximum monolayer adsorption capability of 189.83mg/g, whereas the adsorption kinetics followed the pseudo-second-order kinetics. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Increase in the dosage amount of vitamin D3 preparations by switching from calcium carbonate to lanthanum carbonate.

    Science.gov (United States)

    Hyodo, Toru; Kawakami, Junko; Mikami, Noriko; Wakai, Haruki; Ishii, Daisuke; Yoshida, Kazunari; Iwamura, Masatsugu; Hida, Miho; Kurata, Yasuhisa

    2014-06-01

    It is widely known that dialysis patients who are administered vitamin D preparations have a better prognosis than patients who are not. In this study, of 22 patients on maintenance dialysis who had been administered calcium (Ca) carbonate in our hospital, we investigated the dosage amount of vitamin D3 preparations after the phosphorus (P) binder was switched from Ca carbonate to the newly developed lanthanum carbonate (LC). After completely switching to LC, the dosage amount of oral vitamin D3 preparation (alfacalcidol equivalent) was significantly increased from 0.094 μg/day to 0.375 μg/day (P = 0.0090). No significant changes were observed in the values of serum corrected Ca, alkaline phosphatase, intact parathyroid hormone and P after switching. The administration of LC enabled complete cessation of the administration of Ca carbonate preparations, and increased the dosage amount of vitamin D3 preparations. Therefore, LC may be a useful P binder to improve patient prognosis. © 2014 The Authors. Therapeutic Apheresis and Dialysis © 2014 International Society for Apheresis.

  10. Preparation of self-supporting carbon thin films

    CERN Document Server

    Lommel, B; Kindler, B; Klemm, J; Steiner, J

    2002-01-01

    For heavy-ion beam experiments, self-supporting carbon thin films are needed as targets, stripper foils and as backings (Nucl. Instr. and Meth. A 334 (1993) 69) for materials which cannot be produced self-supporting. Using resistance evaporation under high vacuum, self-supporting carbon foils with a thickness of 5 mu g/cm sup 2 and a diameter of 10 mm, a thickness of 10 mu g/cm sup 2 and a diameter of 50 mm up to a thickness of 50 mu g/cm sup 2 and a diameter of 300 mm can be obtained. Due to the energy impact of the heavy-ion beam, the amorphous carbon is restructured into textured graphite, as was found already by Dollinger et al. (Nucl. Instr. and Meth. A 303 (1991) 79). The discuss the production process as well as the change of the layer structure caused by the energy deposit.

  11. Fe-N-doped carbon catalysts prepared by hybrid PECVD/sputtering system for oxygen reduction reaction

    Science.gov (United States)

    Hotozuka, Kozue; Yoshie, Ryo; Murata, Hidenobu; Tateno, Akira; Ito, Gen; Kawaguchi, Norihito; Matsuo, Takahiro; Ito, Hitomi; Kinoshita, Ikuo; Tachibana, Masaru

    2017-07-01

    A hybrid plasma-enhanced chemical vapor deposition (PECVD)/sputtering system was developed to prepare iron (Fe)-nitrogen (N)-doped carbon catalysts for oxygen reduction reaction (ORR). This hybrid system combines PECVD effective for the synthesis of nanocarbons with sputtering technique for the doping of metals such as Fe where the amount of the doping can be independently controlled during synthesizing nanocarbons. By using this system, Fe-N-doped carbon catalysts are directly synthesized on carbon papers which have been widely used as a gas diffusion layer in fuel cells. The synthesized catalysts with carbon papers exhibit high ORR activity. This is attributed to Fe-N coordination bonds which are stably formed in the synthesized catalysts.

  12. Activated Carbon, Carbon Nanofiber and Carbon Nanotube Supported Molybdenum Carbide Catalysts for the Hydrodeoxygenation of Guaiacol

    Directory of Open Access Journals (Sweden)

    Eduardo Santillan-Jimenez

    2015-03-01

    Full Text Available Molybdenum carbide was supported on three types of carbon support—activated carbon; multi-walled carbon nanotubes; and carbon nanofibers—using ammonium molybdate and molybdic acid as Mo precursors. The use of activated carbon as support afforded an X-ray amorphous Mo phase, whereas crystalline molybdenum carbide phases were obtained on carbon nanofibers and, in some cases, on carbon nanotubes. When the resulting catalysts were tested in the hydrodeoxygenation (HDO of guaiacol in dodecane, catechol and phenol were obtained as the main products, although in some instances significant amounts of cyclohexane were produced. The observation of catechol in all reaction mixtures suggests that guaiacol was converted into phenol via sequential demethylation and HDO, although the simultaneous occurrence of a direct demethoxylation pathway cannot be discounted. Catalysts based on carbon nanofibers generally afforded the highest yields of phenol; notably, the only crystalline phase detected in these samples was Mo2C or Mo2C-ζ, suggesting that crystalline Mo2C is particularly selective to phenol. At 350 °C, carbon nanofiber supported Mo2C afforded near quantitative guaiacol conversion, the selectivity to phenol approaching 50%. When guaiacol HDO was performed in the presence of acetic acid and furfural, guaiacol conversion decreased, although the selectivity to both catechol and phenol was increased.

  13. Activated carbon derived from marine Posidonia Oceanica for electric energy storage

    Directory of Open Access Journals (Sweden)

    N. Boukmouche

    2014-07-01

    Full Text Available In this paper, the synthesis and characterization of activated carbon from marine Posidonia Oceanica were studied. The activated carbon was prepared by a simple process namely pyrolysis under inert atmosphere. The activated carbon can be used as electrodes for supercapacitor devices. X-ray diffraction result revealed a polycrystalline graphitic structure. While scanning electron microscope investigation showed a layered structure with micropores. The EDS analysis showed that the activated carbon contains the carbon element in high atomic percentage. Electrochemical impedance spectroscopy revealed a capacitive behavior (electrostatic phenomena. The specific capacity per unit area of the electrochemical double layer of activated carbon electrode in sulfuric acid electrolyte was 3.16 F cm−2. Cyclic voltammetry and galvanostatic chronopotentiometry demonstrated that the electrode has excellent electrochemical reversibility. It has been found that the surface capacitance was strongly related to the specific surface area and pore size.

  14. Characterization of carbon-encapsulated permalloy nanoparticles prepared through detonation

    Science.gov (United States)

    Li, Xueqi; Li, Xiaojie; Wang, Xiaohong; Pan, Xuncen; Yan, Honghao

    2017-07-01

    Carbon-encapsulated Fe-Ni alloy nanoparticles were synthesized through detonation using two composite explosive precursors doped with Fe (NO3)3 · 9H2O and Ni(NO3)2 · 6H2O · The morphology, components, and magnetism of the synthesized carbon-encapsulated alloy nanoparticles were characterized through x-ray diffraction studies (XRD, Rigaku, D/Max 2400, Japan), Raman spectroscopy (Raman, Thermo Fisher, DXR Microscope, USA), Transmission electron microscopy (TEM, FEI, Technai F30, USA) attached with energy dispersive x-ray spectroscopy (EDS), and vibrating sample magnetometer (VSM, JDM-13, China) analyses. The denotation products of the two precursors were compared. The influence of the components of the two precursors on the products was also analyzed. Results showed that both precursors detonated and synthesized the carbon-encapsulated Fe-Ni nanoparticles with a core-shell structure. The grains exhibited sizes ranging from 10 nm to 100 nm and were uniformly distributed. The encapsulated metal core was mainly composed of different proportions of Fe and Ni. The outer shell was composed of graphite and amorphous carbon. VSM analysis indicated that the detonated composite nanoparticles showed superparamagnetism at room temperature.

  15. Autogenic reactions for preparing carbon-encapsulated, nanoparticulate TiO 2 electrodes for lithium-ion batteries

    Science.gov (United States)

    Pol, Vilas G.; Kang, Sun-Ho; Calderon-Moreno, Jose M.; Johnson, Christopher S.; Thackeray, Michael M.

    We report an anhydrous, autogenic technique for synthesizing electronically interconnected, carbon-encapsulated, nanoparticulate anatase anode materials (TiO 2-C) for lithium-ion batteries. The TiO 2-C nanoparticles provide a reversible capacity of ∼200 mAh g -1, which exceeds the theoretical capacity of the commercially attractive spinel anode, Li 4Ti 5O 12 (175 mAh g -1) and is competitive with the capacity reported for other TiO 2 products. The processing method is extremely versatile and has implications for preparing, in a single step, a wide variety of electrochemically active compounds that are coated, in situ, with carbon.

  16. Preparation of coal-based microfiltration carbon membrane and application in oily wastewater treatment

    Energy Technology Data Exchange (ETDEWEB)

    Song, C.W.; Wang, T.H.; Pan, Y.Q.; Qiu, J.S. [Dalian University of Technology, Dalian (China). Carbon Research Laboratory

    2006-08-15

    The coal-based microfiltration carbon membrane with low cost for the treatment of oily wastewater was prepared by carbonization of tubular carbonaceous precursor obtained by extrusion method. The pore size of carbon membrane was controlled by adjusting the particle size of coal. Effects of pore size of carbon membrane, transmembrane pressure and crossflow velocity on the filtration flux were investigated in the treatment of oily wastewater. The results indicate it is feasible to treat oily wastewater by coal-base microfiltration carbon membrane. The carbon membrane with pore size of 1.0 {mu} m and the operation conditions of 0.10 MPa transmembrane pressure and 0.1 m/s crossflow velocity are recommended. After treated by coal-based microfiltration carbon membrane, the oil rejection coefficients of oily wastewater are up to 97%, and the oil concentrations of the permeate are less than 10 mg/L, which can meet the National Discharge Standard of China for wastewater.

  17. Research Progress in Preparation of Cyclodextrin Functionalized Carbon Nanomaterials and Their Applications in Electrochemical Analysis

    Directory of Open Access Journals (Sweden)

    YI Yin-hui

    2017-12-01

    Full Text Available Cyclodextrin (CD molecules have a toroidal shape with a hydrophobic inner cavity and a hydrophilic exterior. The hydrophobic inner cavity can enable CD molecules to show high molecular selectivity and enrichment capability, and the hydrophilic exterior can make CD have high solubility in various solvents. On the other hand, because of the large theoretical surface areas and excellent electrochemical properties of carbon nanomaterials, they have important potential applications in electroanalytical chemistry. However, pure carbon nanomaterials usually are insoluble in solvents. Thus, it's of great significance to functionalize carbon nanomaterials with CD:CD not only improves the dispersity of carbon nanomaterials, but also enables high molecular selectivity and enrichment capacity, and hence shows extremely high electroanalytical capability. This review shows the methods and mechanism for preparing CD functionalized carbon nanomaterials (carbon nanotube, graphene, hollow carbon sphere,etc. and their applications in electroanalytical chemistry. Finally, some critical challenges and prospects in this field were also briefly discussed.

  18. Significance of the carbonization of volatile pyrolytic products on the properties of activated carbons from phosphoric acid activation of lignocellulosic material

    Energy Technology Data Exchange (ETDEWEB)

    Zuo, Songlin; Yang, Jianxiao; Cai, Xuan [Faculty of Chemical Engineering, Nanjing Forestry University, Nanjing 210037 (China); Liu, Junli [Institute of Chemical Industry of Forest Products, CAF, Nanjing 210042 (China)

    2009-07-15

    Two series of activated carbons derived from China fir (Cunninghamia lanceolata) wood impregnated with phosphoric acid were prepared in a cylindrical container that was kept in a closed state covered with a lid (the covered case) or in an open state. The effects of the carbonization of volatile pyrolytic products of starting materials on the properties of activated carbon were investigated in the process of phosphoric acid activation. Elemental analysis and SEM observation showed that both activating in the covered case and increasing the mass of starting material used favored the carbonization of volatile pyrolytic products. An investigation of N{sub 2} adsorption isotherms revealed that the carbonization of volatile pyrolytic products significantly enhanced mesopore development in the final carbons, especially pores with a size range from 2.5 to 30 nm, with little influence on micropores, and therefore produced a large increase in the adsorption capacity to Vitamin B12 (with a molecular size of 2.09 nm). Activated carbons with highly developed mesopores could be obtained in the covered case. The carbonization mechanism of volatiles was discussed and two different carbonization pathways (in solid and gas phases) were proposed during phosphoric acid activation. (author)

  19. Carbon-mineral adsorbents prepared by pyrolysis of waste materials in the presence of tetrachloromethane.

    Science.gov (United States)

    Leboda, Roman; Charmas, Barbara; Skubiszewska-Zieba, Jadwiga; Chodorowski, Stanislaw; Oleszczuk, Patryk; Gun'ko, Vladimir M; Pokrovskiy, Valery A

    2005-04-01

    Natural bentonite spent in the process of plant oil bleaching was used as an initial material for preparation of carbon-mineral adsorbents. The spent bleaching earth was treated using four procedures: T (thermal treatment); H (hydrothermal treatment); C (thermal treatment with addition of CCl4 vapor); M (modification of porous structure). Raw bentonite, RB (raw bleaching earth), and carbon materials prepared using plant oil were compared. The physicochemical characteristics of the adsorbents were determined using different methods: nitrogen adsorption/desorption, XRD, TEM, and MS-TPD. Carbon-mineral adsorbents contain from 5.23 to 19.92% C (w/w) and carbon adsorbents include from 84.2 to 91.18% C (w/w). Parallel processes of organic substance carbonization, porous structure modification, sublimation or evaporation of metal chlorides, and removal of hydrogen chloride take place during pyrolysis of waste mineral materials in the CCl4 atmosphere.

  20. Spherical carbon particles and carbon nanotubes prepared by autogenic reactions : evaluation as anodes in lithium electrochemical cells.

    Energy Technology Data Exchange (ETDEWEB)

    Pol, V. G.; Thackeray, M. M. (Chemical Sciences and Engineering Division)

    2011-05-01

    Autogenic reactions, based on the decomposition of one or more precursors at elevated temperatures with self generated pressures can be used to prepare a wide range of materials with interesting structural, morphological and technological properties. Recent reports that spherical carbon particles and carbon nanotubes can be prepared by this technique from waste products, such as used plastic bags, have highlighted this environmentally-attractive approach to synthesize new or modified carbon-based materials. In this paper, we report the synthesis of spherical carbon particles and carbon nanotubes and their evaluation as negative electrodes (anodes) in lithium electrochemical cells. A steady reversible capacity of approximately 240 mAh/g for hundreds of cycles was achieved from both types of carbon, when cycled at a 1C rate between 1.5 V and 5 mV. A reversible capacity of 372 mAh/g, i.e., the theoretical value for graphite, was obtained from the carbon nanotube electrodes by raising the upper voltage limit to 3 V. To increase the graphitic order in the carbon spheres, the particles were heated to 2400 C in an inert atmosphere. This treatment reduced the first cycle irreversible capacity loss of Li/C half cells from 60 to 20%, the spherical carbon electrodes yielding a stable 252 mAh/g discharge capacity for numerous cycles. Structural and morphological information about the parent and cycled carbon electrodes, obtained by powder X-ray diffraction, Raman spectroscopy, high-resolution scanning electron microscopy, and electron dispersive analysis of X-rays is provided.

  1. Spherical Carbon Particles and Carbon Nanotubes Prepared by Autogenic Reactions: Evaluation as Anodes in Lithium Electrochemical Cells

    Energy Technology Data Exchange (ETDEWEB)

    Pol, Vilas G.; Thackeray, Michael

    2010-01-01

    Autogenic reactions, based on the decomposition of one or more precursors at elevated temperatures with self generated pressures can be used to prepare a wide range of materials with interesting structural, morphological and technological properties. Recent reports that spherical carbon particles and carbon nanotubes can be prepared by this technique from waste products, such as used plastic bags, have highlighted this environmentally-attractive approach to synthesize new or modified carbon-based materials. In this paper, we report the synthesis of spherical carbon particles and carbon nanotubes and their evaluation as negative electrodes (anodes) in lithium electrochemical cells. A steady reversible capacity of approximately 240 mAh/g for hundreds of cycles was achieved from both types of carbon, when cycled at a 1C rate between 1.5 V and 5 mV. A reversible capacity of 372 mAh/g, i.e., the theoretical value for graphite, was obtained from the carbon nanotube electrodes by raising the upper voltage limit to 3 V. To increase the graphitic order in the carbon spheres, the particles were heated to 2400 °C in an inert atmosphere. This treatment reduced the first cycle irreversible capacity loss of Li/C half cells from 60 to 20%, the spherical carbon electrodes yielding a stable 252 mAh/g discharge capacity for numerous cycles. Structural and morphological information about the parent and cycled carbon electrodes, obtained by powder X-ray diffraction, Raman spectroscopy, high-resolution scanning electron microscopy, and electron dispersive analysis of X-rays is provided.

  2. Platinum dispersed on carbon catalyst for a fuel cell; A preparation with sorbitan monolaurate

    Energy Technology Data Exchange (ETDEWEB)

    Honji, A.; Mori, T.; Hishinuma, Y. (Hitachi Limited, Hitachi Research Lab., 4026 Kuji-cho, Hitachi-shi, Ibaraki-ken 319-12 (JP))

    1990-07-01

    This paper reports platinum highly dispersed on acetylene black by the reduction of chloroplatinic acid with methyl alcohol containing sorbitan monolaurate. When the preparation concentration of sorbitan monolaurate was 5.0 g/liter and the heat-treatment temperature to decompose the residual sorbitan monolaurate in the catalyst was 500{degrees}C, the electrode fabricated with this catalyst showed the highest performance for oxygen reduction in phosphoric acid at 190{degrees}C. The residual surface-active agent was carbonized on heat-treatment and the pore distribution of the catalyst was changed. The time dependence of the change in platinum particle diameter was measured at 0.80 V {ital vs.} RHE in phosphoric acid at 205{degrees}C. The particle diameter hardly changed during a period of about 400 h.

  3. Biomass-based palm shell activated carbon and palm shell carbon molecular sieve as gas separation adsorbents.

    Science.gov (United States)

    Sethupathi, Sumathi; Bashir, Mohammed Jk; Akbar, Zinatizadeh Ali; Mohamed, Abdul Rahman

    2015-04-01

    Lignocellulosic biomass has been widely recognised as a potential low-cost source for the production of high added value materials and proved to be a good precursor for the production of activated carbons. One of such valuable biomasses used for the production of activated carbons is palm shell. Palm shell (endocarp) is an abundant by-product produced from the palm oil industries throughout tropical countries. Palm shell activated carbon and palm shell carbon molecular sieve has been widely applied in various environmental pollution control technologies, mainly owing to its high adsorption performance, well-developed porosity and low cost, leading to potential applications in gas-phase separation using adsorption processes. This mini-review represents a comprehensive overview of the palm shell activated carbon and palm shell carbon molecular sieve preparation method, physicochemical properties and feasibility of palm shell activated carbon and palm shell carbon molecular sieve in gas separation processes. Some of the limitations are outlined and suggestions for future improvements are pointed out. © The Author(s) 2015.

  4. Development of activated carbon using vine shoots (Vitis vinifera) and its use for wine treatment.

    Science.gov (United States)

    Corcho-Corral, B; Olivares-Marín, M; Valdes-Sánchez, E; Fernández-González, C; Macías-García, A; Gómez-Serrano, V

    2005-02-09

    An abundant and low-cost agricultural waste such as vine shoots (Vitis vinifera) (VS), which is generated by the annual pruning of vineyards, has been used as raw material in the preparation of powder activated carbon (AC) with a view to develop a new fining agent for white wines. A commercial activated carbon, S5X-Agrovin, was used for comparison purposes. From VS size-reduced pieces, AC was prepared using phosphoric acid as activating agent. The concentration of the H(3)PO(4) solution, the impregnation temperature, and the carbonization conditions were controlled. The carbons were texturally characterized by gas adsorption (N(2), -196 degrees C), mercury porosimetry, and density measurements. FT-IR spectroscopy was used in the analysis of the surface functional groups and structures of the carbons. Three varieties of white wine (i.e., cv. Cayetana, cv. Macabeo, and cv. Sauvignon Blanc) were treated with the activated carbons. Color changes were monitored by UV-vis spectrometry. Significant differences in the degree of uptake of polyphenols were observed depending on the wine variety and on the method of preparation of activated carbon. The carbon prepared by first impregnation of VS with the 60 vol% H(3)PO(4) solution at 50 degrees C and by then carbonization of the resultant product at 400 degrees C for 2 h presents a higher ability to discolor the white wines. The action of this carbon is comparable to that shown by the commercial product. Both carbons possess a well-developed porosity in the macropore range.

  5. Methods of analyzing carbon nanostructures, methods of preparation of analytes from carbon nanostructures, and systems for analyzing carbon nanostructures

    KAUST Repository

    Da Costa, Pedro Miquel Ferreira Joaquim

    2016-09-09

    Provided herein is a method determining the concentration of impurities in a carbon material, comprising: mixing a flux and a carbon material to form a mixture, wherein the carbon material is selected from the group consisting of graphene, carbon nanotubes, fullerene, carbon onions, graphite, carbon fibers, and a combination thereof; heating the mixture using microwave energy to form fused materials; dissolution of the fused materials in an acid mixture; and measuring the concentration of one or more impurities.

  6. Making Activated Carbon for Storing Gas

    Science.gov (United States)

    Wojtowicz, Marek A.; Serio, Michael A.; Suuberg, Eric M.

    2005-01-01

    Solid disks of microporous activated carbon, produced by a method that enables optimization of pore structure, have been investigated as means of storing gas (especially hydrogen for use as a fuel) at relatively low pressure through adsorption on pore surfaces. For hydrogen and other gases of practical interest, a narrow distribution of pore sizes carbon is alternately (1) heated to the lower of two elevated temperatures in air or other oxidizing gas, causing the formation of stable carbon/oxygen surface complexes; then (2) heated to the higher of the two elevated temperatures in flowing helium or other inert gas, causing the desorption of the surface complexes in the form of carbon monoxide. In the present method, pore structure is optimized partly by heating to a temperature of 1,100 C during carbonization. Another aspect of the method exploits the finding that for each gas-storage pressure, gas-storage capacity can be maximized by burning off a specific proportion (typically between 10 and 20 weight percent) of the carbon during the cyclic chemisorption/desorption process.

  7. Preparation of Nickel-Copper Bilayers Coated on Single-Walled Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    Zhong Zheng

    2015-01-01

    Full Text Available Due to oxidizability of copper coating on carbon nanotubes, the interfacial bond strength between copper coating and its matrix is weak, which leads to the reduction of the macroscopic properties of copper matrix composite. The electroless coating technics was applied to prepare nickel-copper bilayers coated on single-walled carbon nanotubes. The coated single-walled carbon nanotubes were characterized through transmission electron microscope spectroscopy, field-emission electron microscope spectroscopy, X-ray diffractometry, and thermogravimetric analysis. The results demonstrated that the nickel-copper bilayers coated on single-walled carbon nanotubes possessed higher purity of unoxidized copper fine-grains than copper monolayers.

  8. Activation of peroxymonosulfate by graphitic carbon nitride loaded on activated carbon for organic pollutants degradation

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Mingyu; Gao, Long; Li, Jun [School of Environmental Engineering, Wuhan Textile University, Wuhan 430073 (China); Fang, Jia [School of Chemistry and Chemical Engineering, Wuhan Textile University, Wuhan 430073 (China); Cai, Wenxuan [School of Environmental Engineering, Wuhan Textile University, Wuhan 430073 (China); Li, Xiaoxia [School of Chemistry and Chemical Engineering, Wuhan Textile University, Wuhan 430073 (China); Xu, Aihua, E-mail: xahspinel@sina.com [School of Environmental Engineering, Wuhan Textile University, Wuhan 430073 (China); Engineering Research Center for Clean Production of Textile Dyeing and Printing, Ministry of Education, Wuhan 430073 (China)

    2016-10-05

    Highlights: • Supported g-C{sub 3}N{sub 4} on AC catalysts with different loadings were prepared. • The metal free catalysts exhibited high efficiency for dyes degradation with PMS. • The catalyst presented a long-term stability for multiple runs. • The C=O groups played a key role in the oxidation process. - Abstract: Graphitic carbon nitride supported on activated carbon (g-C{sub 3}N{sub 4}/AC) was prepared through an in situ thermal approach and used as a metal free catalyst for pollutants degradation in the presence of peroxymonosulfate (PMS) without light irradiation. It was found that g-C{sub 3}N{sub 4} was highly dispersed on the surface of AC with the increase of surface area and the exposition of more edges and defects. The much easier oxidation of C species in g-C{sub 3}N{sub 4} to C=O was also observed from XPS spectra. Acid Orange 7 (AO7) and other organic pollutants could be completely degraded by the g-C{sub 3}N{sub 4}/AC catalyst within 20 min with PMS, while g-C{sub 3}N{sub 4}+PMS and AC+PMS showed no significant activity for the reaction. The performance of the catalyst was significantly influenced by the amount of g-C{sub 3}N{sub 4} loaded on AC; but was nearly not affected by the initial solution pH and reaction temperature. In addition, the catalysts presented good stability. A nonradical mechanism accompanied by radical generation (HO· and SO{sub 4}·{sup −}) in AO7 oxidation was proposed in the system. The C=O groups play a key role in the process; while the exposure of more N-(C){sub 3} group can further increase its electron density and basicity. This study can contribute to the development of green materials for sustainable remediation of aqueous organic pollutants.

  9. ACTIVATED CARBON/REFRIGERANT COMBINATIONS FOR ...

    African Journals Online (AJOL)

    ES Obe

    No. 1, March, 2001. 53. ACTIVATED CARBON/REFRIGERANT COMBINATIONS. FOR SOLAR REFRIGERATION APPLICATION. By. E.E. ANYANWU. 1. AND N.V. .... may be assumed that the perfect gas law is obeyed approximately by the vapour. Thus,. (2). Hence by integrating,. This linear relationship between log P and.

  10. Catalyst deposition for the preparation of carbon nanotubes

    DEFF Research Database (Denmark)

    2013-01-01

    Disclosed is a method of depositing islands of catalyst with a predetermined density, wherein in said method comprises the steps of: obtaining a diffusion barrier covered nano patterned surface comprising a plurality of plateaus, having a density of plateaus dependent on the predetermined density...... of islands of catalyst; depositing catalyst on said diffusion barrier covered nano patterned surface; and heating the diffusion barrier covered nano patterned surface after catalyst has been deposited, to anneal the catalyst, whereby islands of catalyst is formed. Wherein said diffusion barrier covered nano...... patterned surface is configured to ensure that no more than a single island of catalyst is formed on each plateau, so that a sub sequent growth of carbon nanotubes from the deposited islands result in that no more than a single carbon nanotube is grown from each plateau....

  11. Is Ammonium Peroxydisulate Indispensable for Preparation of Aniline-Derived Iron-Nitrogen-Carbon Electrocatalysts?

    Science.gov (United States)

    Xie, Nan-Hong; Yan, Xiang-Hui; Xu, Bo-Qing

    2016-09-08

    Iron and nitrogen co-doped carbon (Fe-N-C) materials are among the most active non-precious metal catalysts that could replace Pt-based electrocatalysts for the oxygen reduction reaction (ORR) in fuel cells and metal-air batteries. The synthesis of the Fe-N-C catalysts often involves the use of aniline as the precursor for both N and C and ammonium peroxydisulfate (APS) as an indispensable oxidative initiator for aniline polymerization. Herein, a detailed structure and catalytic ORR performance comparison of aniline-derived Fe-N-C catalysts synthesized with and without the use of APS is reported. The APS-free preparation, which uses Fe(III) ions as the Fe source as well as the aniline polymerization initiator, results in a simple Fe-N-C catalyst with a high activity for the ORR. We show that APS is not necessary for the preparation and even detrimental to the performance of the catalyst. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Burner Characteristics for Activated Carbon Production

    Directory of Open Access Journals (Sweden)

    zakaria Supaat

    2017-01-01

    Full Text Available Carbonization process has become an important stage in developing activated carbon. However, existing burner are not efficient in time production which take 24 hours to15 days for charcoal production. Therefore, new design of burner/kilns is quite needed in order to produce larger number of charcoal in short time production, to improve charcoal quality regarding to the smooth surface area and pore volume. This research proposed new design burner which divided into two types which are vertical and horizontal types. Vertical is not completed by auto-rotating system while horizontal type is complete by auto-rotating and fume handling system. It developed using several equipment such as welding, oxy-cutting, drilling grinding and cutting machine. From the result of carbonization process shows that coconut shell charcoal need shorter time of 30 minutes as compared to palm shell charcoal of 2 h to completely carbonized. This result claim that the new design better than existing kiln that need longer time up to 24 h. The result of the palm and coconut shell charcoal believe will produce better properties of activated carbon in large surface area and higher total volume of pores. Therefore, this burner is high recommended for producing palm and coconut shell charcoal as well as other bio-based material.

  13. Preparation and electrochemical performance of ultra-short carbon nanotubes

    Science.gov (United States)

    Wang, Xiao X.; Wang, Jian N.; Su, Lian F.

    Current carbon nanotubes (CNTs) are typically synthesized with micrometer lengths, low dispersion and low purity and thus oppose their applications in many fields. In this study, we make the first report on using a Fe compound (FeS) as a catalyst for controlling the length of CNTs to be less than 300 nm. This is achieved by dissolution of a proper proportion of ferrocene and thiophene in alcohol and pyrolysis of this solution at high temperature. Sulfur, resulting from the decomposition of thiophene, is shown to play key roles in promoting the growth of CNTs and limiting their length. The reason is suggested to be that FeS retards the dissociation of carbon source and diffusion of carbon in it as compared with pure Fe. Short CNTs from the present direct synthesis and from our previous solid-state cutting are used as an electrode material in Li-ion batteries and catalyst supports in fuel cells. Compared with conventional long CNTs, short CNTs show much better electrochemical performance. Due to the simplicity of the present synthetic technique, it may be used for mass production of short CNTs. Furthermore, the application of such a new material may be investigated in wide areas such as information technology, biomedicine, environmental and energy industries.

  14. Ultrahigh surface area carbon from carbonated beverages: Combining self-templating process and in situ activation

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Pengfei; Zhang, Zhiyong; Chen, Jihua; Dai, Sheng

    2015-11-01

    Ultrahigh surface area carbons (USACs, e.g., >2000 m2/g) are attracting tremendous attention due to their outstanding performance in energy-related applications. The state-of-art approaches to USACs involve templating or activation methods and all these techniques show certain drawbacks. In this work, a series of USACs with specific surface areas up to 3633 m2/g were prepared in two steps: hydrothermal carbonization (200 °C) of carbonated beverages (CBs) and further thermal treatment in nitrogen (600–1000 °C). The rich inner porosity is formed by a self-templated process during which acids and polyelectrolyte sodium salts in the beverage formulas make some contribution. This strategy covers various CBs such as Coca Cola®, Pepsi Cola®, Dr. Pepper®, and Fanta® and it enables an acceptable product yield (based on sugars), for example: 21 wt% for carbon (2940 m2/g) from Coca Cola®. Being potential electrode materials for supercapacitors, those carbon materials possessed a good specific capacitance (57.2–185.7 F g-1) even at a scan rate of 1000 mV s-1. Thus, a simple and efficient strategy to USACs has been presented.

  15. On the use of mesophase pitch for the preparation of hierarchical porous carbon monoliths by nanocasting

    Directory of Open Access Journals (Sweden)

    Philipp Adelhelm, Karin Cabrera and Bernd M Smarsly

    2012-01-01

    Full Text Available A detailed study is given on the synthesis of a hierarchical porous carbon, possessing both meso- and macropores, using a mesophase pitch (MP as the carbon precursor. This carbon material is prepared by the nanocasting approach involving the replication of a porous silica monolith (hard templating. While this carbon material has already been tested in energy storage applications, various detailed aspects of its formation and structure are addressed in this study. Scanning electron microscopy (SEM, Hg porosimetry and N2 physisorption are used to characterize the morphology and porosity of the carbon replica. A novel approach for the detailed analysis of wide-angle x-ray scattering (WAXS from non-graphitic carbons is applied to quantitatively compare the graphene microstructures of carbons prepared using MP and furfuryl alcohol (FA. This WAXS analysis underlines the importance of the carbon precursor in the synthesis of templated porous carbon materials via the nanocasting route. Our study demonstrates that a mesophase pitch is a superior precursor whenever a high-purity, low-micropore-content and well-developed graphene structure is desired.

  16. Production of activated carbons from pyrolysis of waste tires impregnated with potassium hydroxide.

    Science.gov (United States)

    Teng, H; Lin, Y C; Hsu, L Y

    2000-11-01

    Activated carbons were produced from waste tires using a chemical activation method. The carbon production process consisted of potassium hydroxide (KOH) impregnation followed by pyrolysis in N2 at 600-900 degrees C for 0-2 hr. The activation method can produce carbons with a surface area (SA) and total pore volume as high as 470 m2/g and 0.57 cm3/g, respectively. The influence of different parameters during chemical activation, such as pyrolysis temperature, holding time, and KOH/tire ratio, on the carbon yield and the surface characteristics was explored, and the optimum preparation conditions were recommended. The pore volume of the resulting carbons generally increases with the extent of carbon gasified by KOH and its derivatives, whereas the SA increases with degree of gasification to reach a maximum value, and then decreases upon further gasification.

  17. Activated carbons from African oil palm waste shells and fibre for hydrogen storage

    Directory of Open Access Journals (Sweden)

    Liliana Giraldo

    2013-06-01

    Full Text Available We prepared a series of activated carbons by chemical activation with two strong bases in-group that few use, and I with waste from shell and fibers and oil-palm African. Activated carbons are obtained with relatively high surface areas (1605 m2/g. We study the textural and chemical properties and its effect on hydrogen storage. The activated carbons obtained from fibrous wastes exhibit a high hydrogen storage capacity of 6.0 wt % at 77 K and 12 bar.

  18. Porous carbon with a large surface area and an ultrahigh carbon purity via templating carbonization coupling with KOH activation as excellent supercapacitor electrode materials

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Fei; Gao, Jihui, E-mail: gaojh@hit.edu.cn; Liu, Xin; Pi, Xinxin; Yang, Yuqi; Wu, Shaohua

    2016-11-30

    Highlights: • Simple templating carbonization method was developed to obtain porous carbons. • Surface etching by KOH activation greatly boosts surface area and carbon purity. • The as-obtained porous carbon delivers a high capacitance of 275 F g{sup −1}. • Symmetric supercapacitor can achieved high energy density and power density. - Abstract: Large surface area and good structural stability, for porous carbons, are two crucial requirements to enable the constructed supercapacitors with high capacitance and long cycling lifespan. Herein, we successfully prepare porous carbon with a large surface area (3175 m{sup 2} g{sup −1}) and an ultrahigh carbon purity (carbon atom ratio of 98.25%) via templating carbonization coupling with KOH activation. As-synthesized MTC-KOH exhibits excellent performances as supercapacitor electrode materials in terms of high specific capacitance and ultrahigh cycling stability. In a three electrode system, MTC-KOH delivers a high capacitance of 275 F g{sup −1} at 0.5 A g{sup −1} and still 120 F g{sup −1} at a high rate of 30 A g{sup −1}. There is almost no capacitance decay even after 10,000 cycles, demonstrating outstanding cycling stability. In comparison, pre-activated MTC with a hierarchical pore structure shows a better rate capability than microporous MTC-KOH. Moreover, the constructed symmetric supercapacitor using MTC-KOH can achieve high energy densities of 8.68 Wh kg{sup −1} and 4.03 Wh kg{sup −1} with the corresponding power densities of 108 W kg{sup −1} and 6.49 kW kg{sup −1}, respectively. Our work provides a simple design strategy to prepare highly porous carbons with high carbon purity for supercapacitors application.

  19. Effect of method of preparation on hydrodesulphurization activity of ...

    Indian Academy of Sciences (India)

    molybdenum sulphide catalysts through precipitation from homogeneous solution (PFHS) technique with the. Mo content varying from 2–12 wt%. The prepared catalysts were evaluated for thiophene hydrodesulphuriza- tion catalytic activities at 400. ◦. C. Catalysts prepared through PFHS method resulted in highly dispersed ...

  20. Preparation and characterization of amphiphilic multi-walled carbon nanotubes

    Science.gov (United States)

    Qiu, Jun; Wang, Guojian; Zhao, Caixia

    2008-04-01

    Multiwalled carbon nanotubes (MWCNTs, average diameter 8 nm) functionalized by N-vinyl pyrrolidone (NVP) were synthesized by radical polymerization and characterized by Fourier transform infrared and Raman spectroscopies, thermogravimetric analysis and transmission electron microscopy. These NVP-MWCNTs exhibit remarkable solubility in water, ethanol and dimethyl formamide. The polyvinyl pyrrolidone can be attached onto the surface of the MWCNTs and the degree of functionalization is affected by NVP content. The functionalization causes possible grafting reaction and solid physical coating between MWCNTs and PVP.

  1. Composite-alumina-carbon molecular sieve membranes prepared from novolac resin and boehmite. Part I: Preparation, characterization and gas permeation studies

    OpenAIRE

    Llosa Tanco, Margot A.; David A. Pacheco Tanaka; Rodrigues, Sandra; Texeira, Miguel; Mendes, Adelio

    2015-01-01

    Supported composite alumina-carbon molecular sieve membranes (c-CMSM) were prepared from in house prepared novolac phenolic resin loaded with boehmite nanoparticles in a single dipping-drying-carbonization step. A porous a-alumina tube support was dipped into a N-methyl-2-pyrrolidone solution containing polymerized novolac resin loaded with boehmite, subsequently dried at 100 C and carbonized at 500 C under nitrogen environment. The structure, morphology and performance of th...

  2. Carbon sink activity of managed grasslands

    Science.gov (United States)

    Klumpp, Katja; Chabbi, Abad; Gastal, Francois; Senapati, Nimai; Charrier, Xavier; Darsonville, Olivier; Creme, Alexandra

    2017-04-01

    In agriculture, a large proportion of GHG emission saving potential may be achieved by means of soil C sequestration. Recent demonstrations of carbon sink activities however, often questioned the existence of C storing grasslands, as uncertainty surrounding estimates are often larger than the sink itself. Besides climate, key components of the carbon sink activity in grasslands are type and intensity of management practices. Here, we analysed long term data on C flux and soil organic carbon stocks for two long term (>13yrs) national observation sites in France (SOERE-ACBB). These sites comprise a number of grassland fields and managements options (i.e. permanent, sowing, grazing, mowing, and fertilization) offering an opportunity to study carbon offsets (i.e. compensation of CH4 and N2O emissions), climatic-management interactions and trade-offs concerning ecosystem services (e.g. production). Furthermore, for some grassland fields, the carbon sink activity was compared using two methods; repeated soil inventory and estimation of the ecosystem C budget by continuous measurement of CO2 exchange (i.e. eddy covariance) in combination with quantification of other C imports and exports, necessary to estimate net C storage. In general grasslands, were a potential sink of C (i.e. net ecosystem exchange, NEE), where grazed sites had lower NEE compared the cut site. However, when it comes to net C storage (NCS), mowing reduced markedly potential sink leading to very low NCS compared to grazed sites. Including non-CO2 fluxes (CH4 and N2O emission) in the budget, revealed that GHG emissions were offset by C sink activity.

  3. Adaptability of activated carbon from palm oil kernel shell in the development of brake friction materials

    Science.gov (United States)

    Talib, R. J.; Amri, M. H.; Selamat, M. A.; Basri, M. Hisyam; Ismail, N. I.; Sulaiman, Z. S.; Jumahat, A.

    2017-12-01

    Four friction material formulations composed of binder, reinforcing fiber, friction modifier and filler have been prepared through powder metallurgy route. The objective of this study is to investigate the possibility of palm oil kernel shell (PKS carbon) to replace the commercial carbon in the fabrication of brake friction materials. Sample H and HB are composed of the same vol. % of ingredients, except that sample H was utilizing commercial carbon (C Carbon) while sample HB was utilizing activated carbon from PKS carbon as their carbon ingredient. Selecting sample HB as based formulation, vol. % of PKS carbon was decreased by 50 % (sample HA) and increased by 50 % (sample HC). The other ingredients in the compositions are proportionally decreased and increased, accordingly. The samples were examined for their porosity, hardness, COF and thickness loss. The three samples which composed of PKS carbon had higher COF than sample which composed of commercial carbon. However, their thickness loss is higher than sample which composed of commercial carbon, particularly sample HC which composed of highest vol. % of PKS carbon. It was observed that sample HB which composed of 20 vol. % of PKS recorded the highest COF and slightly higher thickness loss than sample composed of commercial carbon. Thus, it could be postulated that PKS carbon can be used to replace the commercial carbon in developing a new brake friction material with the best formulation containing 20 vol. % PKS.

  4. Cooperative redox activation for carbon dioxide conversion.

    Science.gov (United States)

    Lian, Zhong; Nielsen, Dennis U; Lindhardt, Anders T; Daasbjerg, Kim; Skrydstrup, Troels

    2016-12-16

    A longstanding challenge in production chemistry is the development of catalytic methods for the transformation of carbon dioxide into useful chemicals. Silane and borane promoted reductions can be fined-tuned to provide a number of C1-building blocks under mild conditions, but these approaches are limited because of the production of stoichiometric waste compounds. Here we report on the conversion of CO2 with diaryldisilanes, which through cooperative redox activation generate carbon monoxide and a diaryldisiloxane that actively participate in a palladium-catalysed carbonylative Hiyama-Denmark coupling for the synthesis of an array of pharmaceutically relevant diarylketones. Thus the disilane reagent not only serves as the oxygen abstracting agent from CO2, but the silicon-containing 'waste', produced through oxygen insertion into the Si-Si bond, participates as a reagent for the transmetalation step in the carbonylative coupling. Hence this concept of cooperative redox activation opens up for new avenues in the conversion of CO2.

  5. Cooperative redox activation for carbon dioxide conversion

    Science.gov (United States)

    Lian, Zhong; Nielsen, Dennis U.; Lindhardt, Anders T.; Daasbjerg, Kim; Skrydstrup, Troels

    2016-12-01

    A longstanding challenge in production chemistry is the development of catalytic methods for the transformation of carbon dioxide into useful chemicals. Silane and borane promoted reductions can be fined-tuned to provide a number of C1-building blocks under mild conditions, but these approaches are limited because of the production of stoichiometric waste compounds. Here we report on the conversion of CO2 with diaryldisilanes, which through cooperative redox activation generate carbon monoxide and a diaryldisiloxane that actively participate in a palladium-catalysed carbonylative Hiyama-Denmark coupling for the synthesis of an array of pharmaceutically relevant diarylketones. Thus the disilane reagent not only serves as the oxygen abstracting agent from CO2, but the silicon-containing `waste', produced through oxygen insertion into the Si-Si bond, participates as a reagent for the transmetalation step in the carbonylative coupling. Hence this concept of cooperative redox activation opens up for new avenues in the conversion of CO2.

  6. Preparation of carbon nanotube bioconjugates for biomedical applications.

    Science.gov (United States)

    Liu, Zhuang; Tabakman, Scott M; Chen, Zhuo; Dai, Hongjie

    2009-01-01

    Biomedical applications of carbon nanotubes have attracted much attention in recent years. Here, we summarize our previously developed protocols for functionalization and bioconjugation of single-walled carbon nanotubes (SWNTs) for various biomedical applications including biological imaging; using nanotubes as Raman, photoluminescence and photoacoustic labels; sensing using nanotubes as Raman tags and drug delivery. Sonication of SWNTs in solutions of phospholipid-polyethylene glycol (PL-PEG) is our most commonly used protocol of SWNT functionalization. Compared with other frequently used covalent strategies, our non-covalent functionalization protocol largely retains the intrinsic optical properties of SWNTs, which are useful in various biological imaging and sensing applications. Functionalized SWNTs are conjugated with targeting ligands, including peptides and antibodies for specific cell labeling in vitro or tumor targeting in vivo. Radio labels are introduced for tracking and imaging of SWNTs in real time in vivo. Moreover, SWNTs can be conjugated with small interfering RNA (siRNA) or loaded with chemotherapy drugs for drug delivery. These procedures take various times ranging from 1 to 5 d.

  7. Preparation of SnO 2 /Carbon Composite Hollow Spheres and Their Lithium Storage Properties

    KAUST Repository

    Lou, Xiong Wen

    2008-10-28

    In this work, we present a novel concept of structural design for preparing functional composite hollow spheres and derived double-shelled hollow spheres. The approach involves two main steps: preparation of porous hollow spheres of one component and deposition of the other component onto both the interior and exterior surfaces of the shell as well as in the pores. We demonstrate the concept by preparing SnO2/carbon composite hollow spheres and evaluate them as potential anode materials for lithium-ion batteries. These SnO2/carbon hollow spheres are able to deliver a reversible Li storage capacity of 473 mA h g-1 after 50 cycles. Unusual double-shelled carbon hollow spheres are obtained by selective removal of the sandwiched porous SnO2 shells. © 2008 American Chemical Society.

  8. 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

  9. Preparation and antidiabetic activity of polysaccharide from ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-02-18

    Feb 18, 2009 ... ginseng (Panax ginseng C.A. Meyer) leaves on lipid peroxidation levels and antioxidant enzyme activities in streptozotocin diabetic rats. J. Ethnopharmacol. 98: 245-250. Li HY, Wang XS (2005). A study on extracting method of polysaccharide from porculata oleracea. J. Branch Campus First Military Med.

  10. Preparation and antidiabetic activity of polysaccharide from ...

    African Journals Online (AJOL)

    Extraction parameters of polysaccharide from Portulaca oleracea L. (POP) and antidiabetic activity of POP on alloxan induced diabetic mice were studied. Better extraction parameters of POP were obtained by the single factor test, as follows: extraction temperature 95°C, extraction time 5 h, and ratio of solvent to raw ...

  11. Investigation on cotton stalk and bamboo sawdust carbonization for barbecue charcoal preparation.

    Science.gov (United States)

    Xiong, Shaowu; Zhang, Shouyu; Wu, Qiaomei; Guo, Xi; Dong, Aixia; Chen, Chuan

    2014-01-01

    In the paper, biochar preparation from cotton stalk and bamboo sawdust by carbonization process was addressed. The physical and chemical properties and combustion characteristics of the biochar prepared using a tubular fixed bed were investigated. The combustion character index (S), the ignition temperature (Ti) and burnout temperature (Tf) were used to evaluate the combustion characteristics of the biochars. The results indicate that the yield and the volatile yield of the biochar decrease and the fixed carbon yield increases with the increase of the carbonization temperature. The ignition temperature and burnout temperature of the biochar increase and the value of S decreases when the carbonization temperature increases. The biochar produced from cotton stalk shows better combustion characteristics than the bamboo sawdust biochar does. Compared with commercial barbecue charcoal, the cotton stalk biochar produced under 600 °C can be utilized as barbecue charcoal. Copyright © 2013. Published by Elsevier Ltd.

  12. Carbon nanomaterials: Biologically active fullerene derivatives.

    Science.gov (United States)

    Bogdanović, Gordana; Djordjević, Aleksandar

    2016-01-01

    Since their discovery, fullerenes, carbon nanotubes, and graphene attract significant attention of researches in various scientific fields including biomedicine. Nano-scale size and a possibility for diverse surface modifications allow carbon nanoallotropes to become an indispensable nanostructured material in nanotechnologies, including nanomedicine. Manipulation of surface chemistry has created diverse populations of water-soluble derivatives of fullerenes, which exhibit different behaviors. Both non-derivatized and derivatized fullerenes show various biological activities. Cellular processes that underline their toxicity are oxidative, genotoxic, and cytotoxic responses.The antioxidant/cytoprotective properties of fullerenes and derivatives have been considered in the prevention of organ oxidative damage and treatment. The same unique physiochemical properties of nanomaterials may also be associated with potential health hazards. Non-biodegradability and toxicity of carbon nanoparticles still remain a great concern in the area of biomedical application. In this review, we report on basic physical and chemical properties of carbon nano-clusters--fullerenes, nanotubes, and grapheme--their specificities, activities, and potential application in biological systems. Special emphasis is given to our most important results obtained in vitro and in vivo using polyhydroxylated fullerene derivative C₆₀(OH)₂₄.

  13. Carbon nanomaterials: Biologically active fullerene derivatives

    Directory of Open Access Journals (Sweden)

    Bogdanović Gordana

    2016-01-01

    Full Text Available Since their discovery, fullerenes, carbon nanotubes, and graphene attract significant attention of researches in various scientific fields including biomedicine. Nano-scale size and a possibility for diverse surface modifications allow carbon nanoallotropes to become an indispensable nanostructured material in nanotechnologies, including nanomedicine. Manipulation of surface chemistry has created diverse populations of water-soluble derivatives of fullerenes, which exhibit different behaviors. Both non-derivatized and derivatized fullerenes show various biological activities. Cellular processes that underline their toxicity are oxidative, genotoxic, and cytotoxic responses. The antioxidant/cytoprotective properties of fullerenes and derivatives have been considered in the prevention of organ oxidative damage and treatment. The same unique physiochemical properties of nanomaterials may also be associated with potential health hazards. Non-biodegradability and toxicity of carbon nanoparticles still remain a great concern in the area of biomedical application. In this review, we report on basic physical and chemical properties of carbon nano-clusters - fullerenes, nanotubes, and graphene - their specificities, activities, and potential application in biological systems. Special emphasis is given to our most important results obtained in vitro and in vivo using polyhydroxylated fullerene derivative C60(OH24. [Projekat Ministarstva nauke Republike Srbije, br. III45005

  14. Preparation and characterization of polycarbonate/multiwalled carbon nanotube nanocomposites

    Directory of Open Access Journals (Sweden)

    Claudio Larosa

    2017-09-01

    Full Text Available A polymer nanocomposite was produced by ultrasonic-assisted dispersion of multiwalled carbon nanotubes (MWCNTs in a polycarbonate matrix using p-xylene and dichloromethane as the solvents. The filler loading was varied from 1 to 3 wt % in order to examine the effect of MWCNTs on the structure and properties of the composites. The nanocomposites were characterized by DSC, DTA, TGA, UV–vis, FTIR and Raman spectroscopy to evaluate the changes induced by the filler in the polymer matrix. UV–vis, FTIR and Raman spectroscopy measurements confirmed the presence of the dispersed phase in the composite films, while TGA and DSC analysis of the nanocomposites revealed enhanced thermal stability and decreased crystallinity, respectively, as compared to the neat polymer. The proposed composites can find application in a number of everyday products where polycarbonate is the base polymer.

  15. Preparation of nitrogen and sulfur co-doped ordered mesoporous carbon for enhanced microwave absorption performance

    Science.gov (United States)

    Yuan, Xiaoyan; Xue, Xingkun; Ma, Hailong; Guo, Shouwu; Cheng, Laifei

    2017-09-01

    Ordered mesoporous carbon nanomaterials (OMCs) co-doped with homogeneous nitrogen and sulfur heteroatoms were prepared by nanocasting with the pyrrole oligomer catalyzed by sulfuric acid as a precursor and ordered mesoporous silica SBA-15 as a hard-template. By multi-technique approach utilization, it was demonstrated that the N and S co-doped OMCs possessed high ordered mesoporous structures, large surface areas and homogeneous distribution of heteroatoms. As a microwave absorber, the as-prepared materials exhibited a minimum reflection loss (RL) of -32.5 dB at the thickness of 2.5 mm and an absorption bandwidth of 3.2 GHz (RL < -10 dB) in X-band (8.2-12.4 GHz). The good microwave absorption performance was mainly originated from the high electrical conductivity induced by the high surface activity and special structures. And microwave energy can be effectively attenuated through multiple reflections and absorptions in complex conductive network. The design strategy in this work would contribute to the production of a lightweight absorber, presenting a strong absorbency and a wide bandwidth in microwave frequency.

  16. Adsorption of cationic dye methylene blue onto activated carbon obtained from horse chestnut kernel

    OpenAIRE

    Momčilović Milan Z.; Purenović Milovan M.; Miljković Milena N.; Bojić Aleksandar Lj.; Ranđelović Marjan S.

    2011-01-01

    Horse chestnut kernel was used as the precursor for the preparation of powdered activated carbon using phosphoric acid as the activating agent. Batch adsorption experiments for the adsorption of cationic dye methylene blue from aqueous solutions were carried out using the obtained carbon as adsorbent. Equilibrium and kinetic experiments were conducted. The equilibrium data were fitted with the Langmuir, Freundlich and Temkin theoretical isotherm models. The best results was obtained in ...

  17. Porous carbon material containing CaO for acidic gas capture: preparation and properties.

    Science.gov (United States)

    Przepiórski, Jacek; Czyżewski, Adam; Pietrzak, Robert; Toyoda, Masahiro; Morawski, Antoni W

    2013-12-15

    A one-step process for the preparation of CaO-containing porous carbons is described. Mixtures of poly(ethylene terephthalate) with natural limestone were pyrolyzed and thus hybrid sorbents could be easily obtained. The polymeric material and the mineral served as a carbon precursor and CaO delivering agent, respectively. We discuss effects of the preparation conditions and the relative amounts of the raw materials used for the preparations on the porosity of the hybrid products. The micropore areas and volumes of the obtained products tended to decrease with increasing CaO contents. Increase in the preparation temperature entailed a decrease in the micropore volume, whereas the mesopore volume increased. The pore creation mechanism is proposed on the basis of thermogravimetric and temperature-programmed desorption measurements. The prepared CaO-containing porous carbons efficiently captured SO2 and CO2 from air. Washing out of CaO from the hybrid materials was confirmed as a suitable method to obtain highly porous carbon materials. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Enhanced capacitive properties of commercial activated carbon by re-activation in molten carbonates

    Science.gov (United States)

    Lu, Beihu; Xiao, Zuoan; Zhu, Hua; Xiao, Wei; Wu, Wenlong; Wang, Dihua

    2015-12-01

    Simple, affordable and green methods to improve capacitive properties of commercial activated carbon (AC) are intriguing since ACs possess a predominant role in the commercial supercapacitor market. Herein, we report a green reactivation of commercial ACs by soaking ACs in molten Na2CO3-K2CO3 (equal in mass ratios) at 850 °C combining the merits of both physical and chemical activation strategies. The mechanism of molten carbonate treatment and structure-capacitive activity correlations of the ACs are rationalized. Characterizations show that the molten carbonate treatment increases the electrical conductivity of AC without compromising its porosity and wettability of electrolytes. Electrochemical tests show the treated AC exhibited higher specific capacitance, enhanced high-rate capability and excellent cycle performance, promising its practical application in supercapacitors. The present study confirms that the molten carbonate reactivation is a green and effective method to enhance capacitive properties of ACs.

  19. Advances in preparing and characterizing low density pan-carbon microcellular foam

    Energy Technology Data Exchange (ETDEWEB)

    Lagasse, R.R.; Leslie, P.K.; Thompson, K.R.; Weagley, R.J.

    1993-09-01

    This report documents an improved preparation of low density microcellular carbon as well as characterization of spatial homogeneity. The report also documents the process for preparing the nficrocellular carbon from poly(acrylonitrile) raw material. A microcellular polymer precursor (0.025 g/cc) is first prepared via a solution-based process and then pyrolyzed to produce the microcellular carbon in a monolithic form (0.05 g/cc). The process improvement developed in this study permits the pore structure of the n-ficrocellular polymer precursor and the microcellular carbon to be reproduced consistently in different laboratories. Pore structure is affected by the completeness of dissolution of the polymer raw material, which variable can be adjusted via dissolution temperature or particle size of the raw material. The second topic in this report involves determining the spatial fluctuation in mass density caused by periodic, millimeter-scale bands, known as `tree rings` visible on machined surfaces of the carbon monoliths. To measure the fluctuations, we developed a high precision, spatially resolved X-ray transmission technique. The periodic bands caused less than {plus_minus}2% variation of mass density in a microcellular carbon having average density 0.041 g/cc.

  20. In vitro adsorption study of fluoxetine in activated carbons and activated carbon fibres

    Energy Technology Data Exchange (ETDEWEB)

    Nabais, J.M. Valente; Mouquinho, A.; Galacho, C.; Carrott, P.J.M.; Ribeiro Carrott, M.M.L. [Centro de Quimica de Evora e Departamento de Quimica da Universidade de Evora, Rua Romao Ramalho no. 59, 7000-671 Evora (Portugal)

    2008-05-15

    We study the in vitro adsorption of fluoxetine hydrochloride by different adsorbents in simulated gastric and intestinal fluid, pH 1.2 and 7.5, respectively. The tested materials were two commercial activated carbons, carbomix and maxsorb MSC30, one activated carbon fibre produced in our laboratory and also three MCM-41 samples, also produced by us. Selected samples were modified by liquid phase oxidation and thermal treatment in order to change the surface chemistry without significant modifications to the porous characteristics. The fluoxetine adsorption follows the Langmuir model. The calculated Q{sub 0} values range from 54 to 1112 mg/g. A different adsorption mechanism was found for the adsorption of fluoxetine in activated carbon fibres and activated carbons. In the first case the most relevant factors are the molecular sieving effect and the dispersive interactions whereas in the activated carbons the mechanism seams to be based on the electrostatic interactions between the fluoxetine molecules and the charged carbon surface. Despite the different behaviours most of the materials tested have potential for treating potential fluoxetine intoxications. (author)

  1. Carbon storage as affected by different site preparation techniques two years after mixed forest stand installation

    Directory of Open Access Journals (Sweden)

    Felicia Fonseca

    2014-04-01

    Full Text Available Aim of study: This study aims at evaluating the impact of site preparation techniques prior to plantation on carbon storage and distribution in a young mixed stand of Pseudotsuga menziesii (PM and Castanea sativa (CS. Area of study: The experimental field was established near Macedo de Cavaleiros, Northern Portugal, at 700 m elevation, mean annual temperature 12ºC and mean annual rainfall 678 mm. Material and Methods: The experimental layout includes three replicates, where the different treatments corresponding to different tillage intensities were randomly distributed (high, moderate and slight intensity, in plots with an area of 375 m2 each. Twenty six months after forest stand installation, samples of herbaceous vegetation (0.49 m2 quadrat, forest species (8 PM and 8 CS and mineral soil (at 0-5, 5-15, 15-30 and 30-60 cm depth were collected in 15 randomly selected points in each treatment, processed in laboratory and analyzed for carbon by elemental carbon analyzer. Main results: The results obtained showed that: (i more than 90% of the total carbon stored in the system is located in the soil, increasing in depth with tillage intensity; (ii the contribution of herbaceous vegetation and related roots to the carbon storage is very low; (iii the amount of carbon per tree is higher in CS than in PM; (iv the global carbon storage was affected by soil tillage generally decreasing with the increase of tillage intensity. Accordingly, carbon storage capacity as affected by the application of different site preparation techniques should be a decision support tool in afforestation schemes.Keywords: Site preparation; forest species; herbaceous vegetation; carbon storage; mineral soil; Portugal.

  2. Interactions of xanthines with activated carbon

    Energy Technology Data Exchange (ETDEWEB)

    Navarrete Casas, R. [Inorganic Chemistry Department, Granada University (Ugr), E-18071 Granada (Spain)]. E-mail: rncasas@ugr.es; Garcia Rodriguez, A. [Inorganic Chemistry Department, Granada University (Ugr), E-18071 Granada (Spain); Rey Bueno, F. [Inorganic Chemistry Department, Granada University (Ugr), E-18071 Granada (Spain); Espinola Lara, A. [Inorganic Chemistry Department, Granada University (Ugr), E-18071 Granada (Spain); Valenzuela Calahorro, C. [Inorganic Chemistry Department, Granada University (Ugr), E-18071 Granada (Spain); Navarrete Guijosa, A. [Inorganic Chemistry Department, Granada University (Ugr), E-18071 Granada (Spain)

    2006-06-30

    Because of their pharmaceutical and industrial applications, we have studied the adsorption of xanthine derivates (caffeine and theophylline) by activated carbon. To this end, we examined kinetic, equilibrium and thermodynamic aspects of the process. This paper reports the kinetics results. The experimental results indicate that the process was first order in C and the overall process was assumed to involve a single, reversible adsorption-desorption process obeying a kinetic law postulated by us.

  3. Anti-Oxidative Activity of An Aqueous Suspension of Commercial Preparation of The Mushroom Coprinus comatus

    OpenAIRE

    Mira Popović; Saša Vukmirović; Nebojša Stilinović; Ivan Čapo; Vida Jakovljević

    2010-01-01

    In this study the effects of an aqueous suspension of a commercial preparation of the mushroom Coprinus comatus on oxidative stress induced in rats by alloxane and carbon tetrachloride was examined. The effects were estimated from changes in the biochemical parameters (xanthine oxidase, glutathione peroxidase and catalase activity, reduced glutathione content, and extent of lipid peroxidation) of liver homogenate as well as histological changes in the liver of the rats treated with alloxane a...

  4. Polymer-assisted deposition of films and preparation of carbon nanotube arrays using the films

    Science.gov (United States)

    Luo, Hongmei; Li, Qingwen; Bauer, Eve; Burrell, Anthony Keiran; McCleskey, Thomas Mark; Jia, Quanxi

    2013-07-16

    Carbon nanotubes were prepared by coating a substrate with a coating solution including a suitable solvent, a soluble polymer, a metal precursor having a first metal selected from iron, nickel, cobalt, and molybdenum, and optionally a second metal selected from aluminum and magnesium, and also a binding agent that forms a complex with the first metal and a complex with the second metal. The coated substrate was exposed to a reducing atmosphere at elevated temperature, and then to a hydrocarbon in the reducing atmosphere. The result was decomposition of the polymer and formation of carbon nanotubes on the substrate. The carbon nanotubes were often in the form of an array on the substrate.

  5. Aqueous mercury adsorption by activated carbons.

    Science.gov (United States)

    Hadi, Pejman; To, Ming-Ho; Hui, Chi-Wai; Lin, Carol Sze Ki; McKay, Gordon

    2015-04-15

    Due to serious public health threats resulting from mercury pollution and its rapid distribution in our food chain through the contamination of water bodies, stringent regulations have been enacted on mercury-laden wastewater discharge. Activated carbons have been widely used in the removal of mercuric ions from aqueous effluents. The surface and textural characteristics of activated carbons are the two decisive factors in their efficiency in mercury removal from wastewater. Herein, the structural properties and binding affinity of mercuric ions from effluents have been presented. Also, specific attention has been directed to the effect of sulfur-containing functional moieties on enhancing the mercury adsorption. It has been demonstrated that surface area, pore size, pore size distribution and surface functional groups should collectively be taken into consideration in designing the optimal mercury removal process. Moreover, the mercury adsorption mechanism has been addressed using equilibrium adsorption isotherm, thermodynamic and kinetic studies. Further recommendations have been proposed with the aim of increasing the mercury removal efficiency using carbon activation processes with lower energy input, while achieving similar or even higher efficiencies. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Elastic Pore Structure in Activated Carbon

    Science.gov (United States)

    Connolly, M. J.; Wexler, Carlos

    2011-11-01

    Adsorbent materials such as activated carbon and Metal-Organic Frameworks (MOFs) have received significant attention as a potential storage material for hydrogen and natural gas. Typically the adsorbent material is assumed to consist of rigid slit- or cylindrical-shaped pores. Recent work, for MOFs in particular, revealed the importance of the mechanical response of the adsorbent in the presence of an adsorbate. In the absence of an adsorbate the pore structure is defined by the size, shape and inter-molecular interactions of the constituent parts of the solid. Here, we demonstrate the flexibility of pore walls in activated carbon and the effect this has on the pore structure of the bulk samples. The interaction is modeled as a competition between Van der Waals interactions between neighboring walls and a resistance to bending due to the rigidity of graphene. Minimal energy configurations were calculated analytically for a simplified potential and numerically for a more realistic potential. The pore structures are discussed in the context of pore measurements on activated carbon samples.

  7. Electrochemical impedance spectroscopy study of carbon electrodes prepared from date pits and fibers of oil palm empty fruit bunches

    Science.gov (United States)

    Hamdan, E.; Deraman, M.; Suleman, M.; Nor, N. S. M.; Basri, N. H.; Hanappi, M. F. Y. M.; Sazali, N. E. S.; Tajuddin, N. S. M.; Omar, R.; Othman, M. A. R.; Shamsudin, S. A.

    2016-11-01

    In this study, we produced pre-carbonized date pits (PDP) and self-adhesive carbon grains (SACGs) from oil palm empty fruit bunches (EFB) by a low temperature (200°C for DP and 280°C for SACGs, respectively) carbonization method followed by KOH treatment to obtain KOH treated PDP (T-PDP) and KOH treated SACGs (T-SACGs). Four sets of green monolith (GMs) denoted as GM-A, GM-B, GM-C and GM-D were prepared respectively from SACGs (100 wt. %), mixture of PDP and SACGs (50:50 wt. %), T-SACGs (100 wt. %), and mixture of T-SACGs and T-PDP (50:50 wt. %), respectively. From these GMs the respective activated carbon monolith (ACMs) electrodes namely ACM-A, ACM-B, ACM-C and ACM-D were prepared via carbonization (N2 carbonization) and activation (CO2 environment). These ACMs electrodes were used to fabricate the corresponding EDLC cells: Cell-A, Cell-B, Cell-C and Cell-D, respectively. The electrochemical impedance spectroscopy tests conducted on the cells found that the Cell-D showed the maximum value of specific capacitance, Csp (˜ 135 F g-1) whereas the Cell-A showed the minimum values of ESR and characteristic response time, respectively, ˜ 2.14 Ω and ˜ 46 s. Therefore, it can be concluded that the KOH treatment can improve the capacitance but caused the increase in the ESR and response time.

  8. Preparation, Applications, and Digital Simulation of Carbon Interdigitated Array Electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Fei; Kolesov, Grigory; Parkinson, Bruce A.

    2014-12-16

    Carbon interdigitated array (IDA) electrodes with features sizes down to 1.2 μm were fabricated by controlled pyrolysis of patterned photoresist. Cyclic voltam-metry of reversible redox species produced the expected steady-state currents. The collection efficiency depends on the IDA electrode spacing, which ranged from around 2.7 to 16.5 μm, with the smaller dimensions achieving higher collection efficiencies of up to 98%. The signal amplification because of redox cycling makes it possible to detect species at relatively low concentrations (10–5 molar) and the small spacing allows detection of transient electrogenerated species with much shorter lifetimes (submillisecond). Digital simulation software that accounts for both the width and height of electrode elements as well as the electrode spacing was developed to model the IDA electrode response. The simulations are in quantitative agreement with experimental data for both a simple fast one electron redox reaction and an electron transfer with a following chemical reaction at the IDAs with larger gaps whereas currents measured for the smallest IDA electrodes, that were larger than the simulated currents, are attributed to convection from induced charge electrokinetic flow. This work was supported as part of the Center for Molecular Electrocatalysis, an Energy Frontier Research Center funded by the Department of Energy, Office of Science Office of Basic Energy Sciences.

  9. Preparation, Characterization, and Modeling of Carbon Nanofiber/Epoxy Nanocomposites

    Directory of Open Access Journals (Sweden)

    Lan-Hui Sun

    2011-01-01

    Full Text Available There is a lack of systematic investigations on both mechanical and electrical properties of carbon nanofiber (CNF-reinforced epoxy matrix nanocomposites. In this paper, an in-depth study of both static and dynamic mechanical behaviors and electrical properties of CNF/epoxy nanocomposites with various contents of CNFs is provided. A modified Halpin-Tsai equation is used to evaluate the Young's modulus and storage modulus of the nanocomposites. The values of Young's modulus predicted using this method account for the effect of the CNF agglomeration and fit well with those obtained experimentally. The results show that the highest tensile strength is found in the epoxy nanocomposite with a 1.0 wt% CNFs. The alternate-current (AC electrical properties of the CNF/epoxy nanocomposites exhibit a typical insulator-conductor transition. The conductivity increases by four orders of magnitude with the addition of 0.1 wt% (0.058 vol% CNFs and by ten orders of magnitude for nanocomposites with CNF volume fractions higher than 1.0 wt% (0.578 vol%. The percolation threshold (i.e., the critical CNF volume fraction is found to be at 0.057 vol%.

  10. Si-doped carbon quantum dots: a facile and general preparation strategy, bioimaging application, and multifunctional sensor.

    Science.gov (United States)

    Qian, Zhaosheng; Shan, Xiaoyue; Chai, Lujing; Ma, Juanjuan; Chen, Jianrong; Feng, Hui

    2014-05-14

    Heteroatom doping of carbon quantum dots not only enables great improvement of fluorescence efficiency and tunability of fluorescence emission, but also provides active sites in carbon dots to broaden their application in sensor. Silicon as a biocompatible element offers a promising direction for doping of carbon quantum dots. Si-doped carbon quantum dots (SiCQDs) were synthesized through a facile and effective approach. The as-prepared Si-doped carbon quantum dots possess visible fluorescence with high quantum yield up to 19.2%, owing to fluorescence enhancement effect of introduced silicon atoms into carbon dots. The toxicity test on human Hela cells showed that SiCQDs have lower cellular toxicity than common CQDs, and bioimaging experiments clearly demonstrated their excellent biolabelling ability and outstanding performance in resistance to photobleaching. Strong fluorescence quenching effect of Fe(III) on SiCQDs can be used for its selective detection among general metal ions. Specific electron transfer between SiCQDs and hydrogen peroxide enables SiCQDs as a sensitive fluorescence sensing platform for hydrogen peroxide. The subsequent fluorescence recovery induced by removal of hydrogen peroxide from SiCQDs due to formation of the stable adducts between hydrogen peroxide and melamine was taken advantage of to construct effective sensor for melamine.

  11. Elastic modulus of diamond-like carbon films prepared by pulsed vacuum arc

    Science.gov (United States)

    Schultrich, B.; Scheibe, H.-J.; Grandremy, G.; Schneider, D.; Siemroth, P.

    1994-12-01

    Amorphous carbon films have been prepared by special pulsed vacuum arc depositon methods allowing high currents up to 1 kA and more. The Young's modulus of these films has been determined with respect to various technological parameters. For these measurements a method based on the propagation of ultrasonic surface waves has been applied which has been specially designed for the investigation of thin films below one micrometer. Large changes of the elastic modulus, depending on the technology, have been observed, contrasting with the common understanding of invariability of the elastic behavior. Reflecting the large structural variations possible in amorphous carbon, the elastic modulus represents a suitable parameter for characterizing the carbon-carbon network. Furthermore, the elastic modulus of amorphous carbon films may be used for a first estimation of film hardness because of the strong correlation of these two quantities.

  12. Preparation and Characterization of Lanthanum Carbonate Octahydrate for the Treatment of Hyperphosphatemia

    Directory of Open Access Journals (Sweden)

    Anqi He

    2013-01-01

    Full Text Available We proposed a new approach to prepare lanthanum carbonate via reactions between lanthanum chloride and NaHCO3. In the reaction, small amount of NaHCO3 solution was firstly added to the acidic lanthanum chloride solution to generate lanthanum carbonate nuclei and then NaHCO3 is added to the lanthanum chloride at a constant speed. This approach makes both precipitation reaction and neutralization reaction take place simultaneously. Consequently, lanthanum carbonate is produced at low pH environment (pH below 4.0 so that the risk of generating lanthanum carbonate hydroxide is reduced. The product of the above reaction is validated by EDTA titration, elemental analysis, and XRD characterization. In addition, we established a FTIR spectroscopic method to identify La(OHCO3 from La2(CO32·8H2O. Lanthanum carbonate exhibits considerable ability to bind phosphate.

  13. Characteristics of an activated carbon monolith for a helium adsorption compressor

    NARCIS (Netherlands)

    Lozano-Castello, D.; Jorda-Beneyto, M.; Cazorla-Amoros, D.; Linares-Solano, A.; Burger, Johannes Faas; ter Brake, Hermanus J.M.; Holland, Herman J.

    2010-01-01

    An activated carbon monolith (ACM) with a high helium adsorption/desorption capacity, high density, low pressure drop, low thermal expansion and good mechanical properties was prepared and applied successfully in a helium adsorption compressor as a part of a 4.5 K sorption cooler. The activated

  14. Activated carbon from baobab fruit shells through domestic processes

    African Journals Online (AJOL)

    Commercially produced activated carbon is expensive. The aim of the research was to investigate the production of activated carbon from baobab fruit shells (a cheap raw material) using a method that can be employed at rural homesteads in removing organic pollutants. Two methods of producing activated carbon were ...

  15. 78 FR 13894 - Certain Activated Carbon From China

    Science.gov (United States)

    2013-03-01

    ... COMMISSION Certain Activated Carbon From China Determination On the basis of the record \\1\\ developed in the... antidumping duty order on certain activated carbon from China would be likely to lead to continuation or... USITC Publication 4381 (February 2013), entitled Certain Activated Carbon from China: Investigation No...

  16. Less-costly activated carbon for sewage treatment

    Science.gov (United States)

    Ingham, J. D.; Kalvinskas, J. J.; Mueller, W. A.

    1977-01-01

    Lignite-aided sewage treatment is based on absorption of dissolved pollutants by activated carbon. Settling sludge is removed and dried into cakes that are pyrolyzed with lignites to yield activated carbon. Lignite is less expensive than activated carbon previously used to supplement pyrolysis yield.

  17. Carbon Monoxide Chemisorption- Characterization and Testing of Prepared Nickel Catalysts for Amination of Ethanol

    OpenAIRE

    Hanafi Setiawan, Achmad

    1994-01-01

    Three types of nickel metal catalyst supported on silica gel have been prepared using impregnation, ion exchanged sodium hydroxide and ion exchanged ammonia methods, in order to investigate the influence of preparation methods on metal dispersion and their activities for amination of ethanol. All the catalyst samples had a nominal nickel loading of 5 % (w/w). After preparation, the catalysts were activated by a drying stage followed by calcination and reduction. The result of transferring the...

  18. Carbon-based Composite Electrodes : Preparation, Characterization and Application in Electroanalysis

    NARCIS (Netherlands)

    Corb, I.; Manea, F.; Radovan, C.; Pop, A.; Burtica, G.; Malchev, P.G.; Picken, S.J.; Schoonman, J.

    2007-01-01

    Electrodes based on carbon, i.e., expanded graphite (20%, wt.)-epoxy composite (20EG-Epoxy) and expanded graphite (20%, wt.)-polystyrene composite (20EG-PS) have been prepared, characterized using scanning electron microscopy (SEM) and cyclic voltammetry (CV), and tested as anodic sensors. The

  19. Preparation of Designed Poly(trimethylene carbonate) Meniscus Implants by Stereolithography : Challenges in Stereolithography

    NARCIS (Netherlands)

    van Bochove, Bas; Hannink, Gerjon; Buma, Pieter; Grijpma, Dirk W.

    2016-01-01

    Three-armed poly(trimethylene carbonate) macromers with a relatively high molecular weight of 28.9 kg mol(-1) are prepared by ring opening polymerization and subsequent functionalization with methacrylate end groups. A resin suitable for processing by stereolithography is developed using propylene

  20. A novel method for preparation of hollow and solid carbon spheres

    Indian Academy of Sciences (India)

    Wintec

    Abstract. Hollow and solid carbon spheres were prepared by the reaction of ferrocene and ammonium carbo- nate in a sealed quartz tube at 500°C. The morphology and microstructure of the product were characterized by X-ray diffraction, Raman spectroscopy, scanning electron microscopy and transmission electron ...

  1. Field emission from individual multiwalled carbon nanotubes prepared in an electron microscope

    NARCIS (Netherlands)

    de Jonge, N.; van Druten, N.J.

    2003-01-01

    Individual multiwalled carbon nanotube field emitters were prepared in a scanning electron microscope. The angular current density, energy spectra, and the emission stability of the field-emitted electrons were measured. An estimate of the electron source brightness was extracted from the

  2. Preparation of Designed Poly(trimethylene carbonate) Meniscus Implants by Stereolithography: Challenges in Stereolithography

    NARCIS (Netherlands)

    van Bochove, Bas; Hannink, G.; Buma, P.; Grijpma, Dirk W.

    2016-01-01

    Three-armed poly(trimethylene carbonate) macromers with a relatively high molecular weight of 28.9 kg mol−1 are prepared by ring opening polymerization and subsequent functionalization with methacrylate end groups. A resin suitable for processing by stereolithography is developed using propylene

  3. Effect of mesoporous carbon microtube prepared by carbonizing the poplar catkin on sulfur cathode performance in Li/S batteries

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yongguang; Zhao, Yan [Research Institute for Energy Equipment Materials, Hebei University of Technology, Tianjin 300130 (China); Konarov, Aishuak; Li, Zhi [Department of Chemical Engineering, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L3G1 (Canada); Chen, P., E-mail: p4chen@uwaterloo.ca [Department of Chemical Engineering, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L3G1 (Canada)

    2015-01-15

    Highlights: • CMT was synthesized by carbonizing poplar catkins and used in Li/S battery. • CMT with mesoporous surface is beneficial to trapping soluble polysulfides. • The S/CMT composite exhibited good cycling and rate capability. - Abstract: A carbon microtube (CMT) was synthesized by carbonizing the poplar catkin and composited with sulfur, serving as a cathode for lithium/sulfur batteries. Scanning electron microscopy and energy dispersive spectroscopy mapping showed the formation of a tubular structure with uniform sulfur coating on the surface of CMTs. The CMT with a mesoporous surface is beneficial to both trapping soluble polysulfide intermediates and rendering the electrical conductivity of the prepared electrode. The resulting S/CMT composite cathode can deliver an 810 mAh g{sup −1} reversible specific discharge capacity after 100 cycles at 0.1 C, and 585 mAh g{sup −1} at 1 C.

  4. Carbon xerogel microspheres and monoliths from resorcinol-formaldehyde mixtures with varying dilution ratios: preparation, surface characteristics, and electrochemical double-layer capacitances.

    Science.gov (United States)

    Zapata-Benabithe, Zulamita; Carrasco-Marín, Francisco; de Vicente, Juan; Moreno-Castilla, Carlos

    2013-05-21

    Carbon xerogels in the form of microspheres and monoliths were obtained from the sol-gel polymerization of resorcinol and formaldehyde in the presence of potassium carbonate as catalyst, using water as solvent and two different molar dilution ratios. The objectives of this study were as follows: to investigate the effect of the dilution ratio, polymerization reaction time, and temperature on the rheological properties of the sols used to prepare the carbon xerogel microspheres and monoliths; and to determine the influence of their preparation methods and shapes on their surface characteristics and electrochemical double-layer (EDL) capacitance. An increase in the molar dilution ratio produced a decrease in the apparent activation energy of the sol-gel transition. Carbon xerogel microspheres were steam-activated at different burnoff percentages. The morphology, surface area, porosity, and surface chemistry of samples were determined. The main difference between the carbon xerogel microspheres and monoliths was that the latter are largely mesoporous. Better electrochemical behavior was shown by carbon xerogels in monolith than in microsphere form, but higher gravimetric and volumetric capacitances were found in activated carbon xerogel microspheres than in carbon xerogel monoliths.

  5. New catalyst supports prepared by surface modification of graphene- and carbon nanotube structures with nitrogen containing carbon coatings

    Science.gov (United States)

    Oh, Eun-Jin; Hempelmann, Rolf; Nica, Valentin; Radev, Ivan; Natter, Harald

    2017-02-01

    We present a new and facile method for preparation of nitrogen containing carbon coatings (NCC) on the surface of graphene- and carbon nanotubes (CNT), which has an increased electronic conductivity. The modified carbon system can be used as catalyst support for electrocatalytic applications, especially for polymer electrolyte membrane fuel cells (PEMFC). The surface modification is performed by impregnating carbon structures with a nitrogen containing ionic liquid (IL) with a defined C:N ratio, followed by a thermal treatment under ambient conditions. We investigate the influence of the main experimental parameters (IL amount, temperature, substrate morphology) on the formation of the NCC. Additionally, the structure and the chemical composition of the resulting products are analyzed by electron microscopic techniques (SEM, TEM), energy disperse X-ray analysis (EDX), X-ray photoelectron spectroscopy (XPS) and hot extraction analysis. The modified surface has a nitrogen content of 29 wt% which decreases strongly at temperatures above 600 °C. The new catalyst supports are used for the preparation of PEMFC anodes which are characterized by polarization measurements and electrochemical impedance spectroscopy (EIS). Compared to unmodified graphene and CNT samples the electronic conductivity of the modified systems is increased by a factor of 2 and shows improved mass transport properties.

  6. Characterization by SEM, TEM and Quantum-Chemical Simulations of the Spherical Carbon with Nitrogen (SCN Active Carbon Produced by Thermal Decomposition of Poly(vinylpyridine-divinylbenzene Copolymer

    Directory of Open Access Journals (Sweden)

    Vladyslav V. Lisnyak

    2009-09-01

    Full Text Available Amorphous Spherical Carbon with Nitrogen (SCN active carbon has been prepared by carbonization of poly(vinylpyridine-divinylbenzene (PVPDVB copolymer. The PVPDVB dehydrogenation copolymer has been quantum chemically (QC simulated using cluster and periodic models. Scanning electron microscopy (SEM, transmission electron microscopy (TEM and energy dispersive X-ray (EDX studies of the resulting product have conformed the QC computation results. Great structural similarity is found both at the nano- and micro-levels between the N-doped SCN carbon and its pure carbonic SKS analog.

  7. A systematic investigation of the preparation and properties of composite carbon molecular sieves containing inorganic oxides

    Science.gov (United States)

    Foley, Henry C.

    1990-01-01

    The objective of this research is to define the methodology for the preparation and characterization of new carbon-based molecular sieves with composite structures. Carbon molecular sieves have found increasing application in the field of separation and purification of gases. These materials are relatively easy to prepare and their surfaces can be modified to some extent. It is expected that by combining inorganic oxides with the carbonaceous structure one can begin to design composite materials with a wider range of possible chemical and physical properties. In this way, the IOM-CMS materials may confer distinct advantages over pure carbon molecular sieves, not just for separation, but also for catalysis. The most recent results in the design and characterization of these IOM-CMS materials are reviewed and summarized. Directions for further research are also presented.

  8. Method for the preparation of high surface area high permeability carbons

    Science.gov (United States)

    Lagasse, R.R.; Schroeder, J.L.

    1999-05-11

    A method for preparing carbon materials having high surface area and high macropore volume to provide high permeability. These carbon materials are prepared by dissolving a carbonizable polymer precursor, in a solvent. The solution is cooled to form a gel. The solvent is extracted from the gel by employing a non-solvent for the polymer. The non-solvent is removed by critical point drying in CO{sub 2} at an elevated pressure and temperature or evaporation in a vacuum oven. The dried product is heated in an inert atmosphere in a first heating step to a first temperature and maintained there for a time sufficient to substantially cross-link the polymer material. The cross-linked polymer material is then carbonized in an inert atmosphere. 3 figs.

  9. Carbon nanotubes functionalized by click chemistry as scaffolds for the preparation of electrochemical immunosensors. Application to the determination of TGF-beta 1 cytokine

    OpenAIRE

    Sánchez Tirado, Esther; González Cortés, Araceli; Yáñez Sedeño, Paloma; Pingarrón Carrazon, José Manuel

    2016-01-01

    An electrochemical immunosensor for the determination of the multifunctional Transforming Growth Factor β1 (TGF-β1) cytokine has been prepared using multi-walled carbon nanotube (MWCNT)-modified screen-printed carbon electrodes. MWCNTs were functionalized by means of copper(i) catalyzed azide-alkyne cycloaddition ("click" chemistry) as an efficient strategy for the covalent immobilization of immunoreagents without altering their configurations and preserving their biological activity. Alkyne-...

  10. Carbon Dioxide as a Traceless Caramelization Promotor: Preparation of Prebiotic Difructose Dianhydrides (DFAs)-Enriched Caramels from d-Fructose.

    Science.gov (United States)

    Audemar, Maïté; Atencio-Genes, Loyda; Ortiz Mellet, Carmen; Jérôme, François; Garcia Fernandez, José Manuel; De Oliveira Vigier, Karine

    2017-08-02

    Activation of a concentrated solution of d-fructose with carbonic acid, generated from carbon dioxide, induces the formation of difructose dianhydrides (DFAs) and their glycosylated derivatives (glycosyl-DFAs), a family of prebiotic oligosaccharides. Under optimized conditions, up to 70% of the active DFA species were obtained from a highly concentrated solution of fructose, avoiding the filtration step and contamination risk associated with the current procedures that employ heterogeneous catalysis with acid ion-exchange resins. The optimized CO2-promoted preparation of DFA-enriched caramel described here has been already successfully scaled up to 150 kg of d-fructose for nutritional studies, showing that implementation of this process is possible at a larger scale.

  11. Continuous preparation of carbon-nanotube-supported platinum catalysts in a flow reactor directly heated by electric current

    Directory of Open Access Journals (Sweden)

    Alicja Schlange

    2011-10-01

    Full Text Available In this contribution we present for the first time a continuous process for the production of highly active Pt catalysts supported by carbon nanotubes by use of an electrically heated tubular reactor. The synthesized catalysts show a high degree of dispersion and narrow distributions of cluster sizes. In comparison to catalysts synthesized by the conventional oil-bath method a significantly higher electrocatalytic activity was reached, which can be attributed to the higher metal loading and smaller and more uniformly distributed Pt particles on the carbon support. Our approach introduces a simple, time-saving and cost-efficient method for fuel cell catalyst preparation in a flow reactor which could be used at a large scale.

  12. Magnetic properties of magnetic glass-like carbon prepared from furan resin alloyed with magnetic fluid

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Kazumasa, E-mail: naka@sss.fukushima-u.ac.jp [Materials Science Area, Graduate School of Symbiotic Systems Science and Technology, Fukushima University, 1 Kanayagawa, Fukushima 960-1296 (Japan); Okuyama, Kyoko [Materials Science Area, Graduate School of Symbiotic Systems Science and Technology, Fukushima University, 1 Kanayagawa, Fukushima 960-1296 (Japan); Takase, Tsugiko [Institute of Environmental Radioactivity (IER), Fukushima University, 1 Kanayagawa, Fukushima 960-1296 (Japan)

    2017-03-01

    Magnetic glass-like carbons that were heat-treated at different temperatures or were filled with different magnetic nanoparticle contents were prepared from furan resin alloyed with magnetic fluid (MF) or Fe{sub 3}O{sub 4} powder in their liquid-phase states during mixing. Compared to the Fe{sub 3}O{sub 4} powder-alloyed carbon, the MF-alloyed carbon has highly dispersed the nanoparticles, and has the excellent saturation magnetization and coercivity. It is implied that saturation magnetizations are related to changes in the types of phases for the nanoparticles and the relative intensities of X-ray diffraction peaks for iron and iron-containing compounds in the carbons. Additionally, the coercivities are possibly affected by the size and crystallinity of the nanoparticles, the relative amounts of iron, and the existence of amorphous compounds on the carbon surfaces. - Highlights: • Magnetic glass-like carbons were prepared from furan resin alloyed with magnetic fluid. • The nanoparticles of MF-alloyed GLCs were highly dispersed. • MF-alloyed GLCs had excellent magnetic properties compared to powder-alloyed ones. • The magnetic properties changed with treatment temperature and nanoparticle content. • The changes in magnetic properties were investigated with XRD and FE-SEM.

  13. Activated Carbon-Supported Tetrapropylammonium Perruthenate Catalysts for Acetylene Hydrochlorination

    Directory of Open Access Journals (Sweden)

    Xing Li

    2017-10-01

    Full Text Available The Ru-based catalysts, including Ru/AC (activated carbon, TPAP (tetrapropylammonium perruthenate/AC, TPAP/AC-HNO3, and TPAP/AC-HCl, were prepared and assessed for the direct synthesis of vinyl chloride monomer. The results indicate that the TPAP/AC-HCl catalyst exhibits the best performance with the conversion falling from 97% to 91% in 48 hours’ reaction under the conditions of 180 °C, a GHSV(C2H2 of 180 h−1, and the feed ratio VHCl/VC2H2 of 1.15. The substitution of RuCl3 precursor with high valent TPAP species leads to more ruthenium oxides active species in the catalysts; the acidification treatment of carrier in TPAP/AC catalyst can produce an enhanced interaction between the active species and the modified functional groups on the carrier, and it is beneficial to inhibit the carbon deposition and sintering of ruthenium species in the reaction process, greatly increase the adsorption ability of reactants, and further increase the amount of dominating active species in the catalysts, thus improving the catalytic performance. This also provides a promising strategy to explore high efficient and economic mercury-free catalysts for the hydrochlorination of acetylene.

  14. Photocatalytic Activity and Characterization of Carbon-Modified Titania for Visible-Light-Active Photodegradation of Nitrogen Oxides

    Directory of Open Access Journals (Sweden)

    Chun-Hung Huang

    2012-01-01

    Full Text Available A variety of carbon-modified titania powders were prepared by impregnation method using a commercial available titania powder, Hombikat UV100, as matrix material while a range of alcohols from propanol to hexanol were used as precursors of carbon sources. Rising the carbon number of alcoholic precursor molecule, the modified titania showed increasing visible activities of NOx photodegradation. The catalyst modified with cyclohexanol exhibited the best activities of 62%, 62%, 59%, and 54% for the total NOx removal under UV, blue, green, and red light irradiation, respectively. The high activity with long wavelength irradiation suggested a good capability of photocatalysis in full visible light spectrum. Analysis of UV-visible spectrum indicated that carbon modification promoted visible light absorption and red shift in band gap. XPS spectroscopic analysis identified the existence of carbonate species (C=O, which increased with the increasing carbon number of precursor molecule. Photoluminescence spectra demonstrated that the carbonate species suppressed the recombination rate of electron-hole pair. As a result, a mechanism of visible-light-active photocatalyst was proposed according to the formation of carbonate species on carbon-modified TiO2.

  15. Polyherbal preparation for anti-diabetic activity: a screening study.

    Science.gov (United States)

    Srivastava, Noopur; Tiwari, Gaurav; Tiwari, Ruchi

    2010-04-01

    To screen the Polyherbal preparation for anti-diabetic activity in rats. The blood glucose lowering activity of the Polyherbal preparation-I (1:1:1 of Wheat germ oil, Coriandrum sativum and Aloe vera) was studied in normal rats after oral administration at doses of 1.0 and 2.0 ml/kg and Polyherbal preparation-I, II (Wheat germ oil, fresh juice of C. sativum and Aloe vera in the ratio of 2:2:1), and III (Wheat germ oil, fresh juice of C. sativum and Aloe vera in the ratio of 1:2:2) on alloxan-induced diabetic rats, after oral administration at doses of 1.0 and 2.0 ml/kg. Blood samples were collected from the tail vein method at 0, 0.5, 1, 2, 4, 8, 12, and 24 h in normal rats and in diabetic rats at 0, 1, 3, 7, 15, and 30 days. Blood plasma glucose was estimated by the GOD/POD (glucose oxidase and peroxidase) method. The data was compared statistically using the one-way ANOVA method followed by the Dunnett multiple component test. Statistical significance was set at P<0.05. The Polyherbal preparation-I produced significant (P<0.05) reduction in the blood glucose level of normal rats and Polyherbal preparation-I, II, and III produced significant (P<0.01) reduction in the blood glucose level of diabetic rats during 30 days study and compared with that of control and Glibenclamide. The Polyherbal preparation-I showed a significant glucose lowering effect in normal rats and Polyherbal preparation-I, II, and III in diabetic rats. This preparation is going to be promising anti-diabetic preparation for masses; however, it requires further extensive studies in human beings.

  16. Comparison of Surface and Structural Properties of Carbonaceous Materials Prepared by Chemical Activation of Tomato Paste Waste: The Effects of Activator Type and Impregnation Ratio

    Directory of Open Access Journals (Sweden)

    Nurgul Ozbay

    2016-01-01

    Full Text Available Activated carbons were prepared by carbonization of tomato paste processing industry waste at 500°C followed by chemical activation with KOH, K2CO3, and HCl in N2 atmosphere at low temperature (500°C. The effects of different activating agents and impregnation ratios (25, 50, and 100 wt.% on the materials’ characteristics were examined. Precursor, carbonized tomato waste (CTW, and activated carbons were characterized by using ultimate and proximate analysis, thermogravimetric analysis (TG/DTG, Fourier transform-infrared (FT-IR spectroscopy, X-ray fluorescence (XRF spectroscopy, point of zero charge measurements (pHPZC, particle size analyzer, scanning electron microscopy (SEM, energy dispersive X-ray (EDX spectroscopy, nitrogen adsorption/desorption isotherms, and X-ray diffraction (XRD analysis. Activation process improved pore formation and changed activated carbons’ surface characteristics. Activated carbon with the highest surface area (283 m3/g was prepared by using 50 wt.% KOH as an activator. According to the experimental results, tomato paste waste could be used as an alternative precursor to produce low-cost activated carbon.

  17. Development of Formaldehyde Adsorption using Modified Activated Carbon – A Review

    Directory of Open Access Journals (Sweden)

    W.D.P Rengga

    2012-11-01

    Full Text Available Gas storage is a technology developed with an adsorptive storage method, in which gases are stored as adsorbed components on the certain adsorbent. Formaldehyde is one of the major indoor gaseous pollutants. Depending on its concentration, formaldehyde may cause minor disorder symptoms to a serious injury. Some of the successful applications of technology for the removal of formaldehyde have been reported. However, this paper presents an overview of several studies on the elimination of formaldehyde that has been done by adsorption method because of its simplicity. The adsorption method does not require high energy and the adsorbent used can be obtained from inexpensive materials. Most researchers used activated carbon as an adsorbent for removal of formaldehyde because of its high adsorption capacity. Activated carbons can be produced from many materials such as coals, woods, or agricultural waste. Some of them were prepared by specific activation methods to improve the surface area. Some researchers also used modified activated carbon by adding specific additive to improve its performance in attracting formaldehyde molecules. Proposed modification methods on activation and additive impregnated carbon are thus discussed in this paper for future development and improvement of formaldehyde adsorption on activated carbon. Specifically, a waste agricultural product is chosen for activated carbon raw material because it is renewable and gives an added value to the materials. The study indicates that the performance of the adsorption of formaldehyde might be improved by using modified activated carbon. Bamboo seems to be the most appropriate raw materials to produce activated carbon combined with applying chemical activation method and addition of metal oxidative catalysts such as Cu or Ag in nano size particles. Bamboo activated carbon can be developed in addition to the capture of formaldehyde as well as the storage of adsorptive hydrogen gas that

  18. Application of thermal analysis techniques in activated carbon production

    Science.gov (United States)

    Donnals, G.L.; DeBarr, J.A.; Rostam-Abadi, M.; Lizzio, A.A.; Brady, T.A.

    1996-01-01

    Thermal analysis techniques have been used at the ISGS as an aid in the development and characterization of carbon adsorbents. Promising adsorbents from fly ash, tires, and Illinois coals have been produced for various applications. Process conditions determined in the preparation of gram quantities of carbons were used as guides in the preparation of larger samples. TG techniques developed to characterize the carbon adsorbents included the measurement of the kinetics of SO2 adsorption, the performance of rapid proximate analyses, and the determination of equilibrium methane adsorption capacities. Thermal regeneration of carbons was assessed by TG to predict the life cycle of carbon adsorbents in different applications. TPD was used to determine the nature of surface functional groups and their effect on a carbon's adsorption properties.

  19. Production of activated carbon from TCR char

    Science.gov (United States)

    Stenzel, Fabian; Heberlein, Markus; Klinner, Tobias; Hornung, Andreas

    2016-04-01

    The utilization of char for adsorptive purposes is known since the 18th century. At that time the char was made of wood or bones and used for decoloration of fluids. In the 20th century the production of activated carbon in an industrial scale was started. The today's raw materials for activated carbon production are hard coal, peat, wood or coconut shells. All these materials entail costs especially the latter. Thus, the utilization of carbon rich residues (biomass) is an interesting economic opportunity because it is available for no costs or even can create income. The char is produced by thermo-catalytic reforming (TCR®). This process is a combination of an intermediate pyrolysis and subsequently a reforming step. During the pyrolysis step the material is decomposed in a vapor and a solid carbon enriched phase. In the second step the vapor and the solid phase get in an intensive contact and the quality of both materials is improved via the reforming process. Subsequently, the condensables are precipitated from the vapor phase and a permanent gas as well as oil is obtained. Both are suitable for heat and power production which is a clear advantage of the TCR® process. The obtained biochar from the TCR® process has special properties. This material has a very low hydrogen and oxygen content. Its stability is comparable to hard coal or anthracite. Therefore it consists almost only of carbon and ash. The latter depends from input material. Furthermore the surface structure and area can be influenced during the reforming step. Depending from temperature and residence time the number of micro pores and the surface area can be increased. Preliminary investigations with methylene blue solution have shown that a TCR® char made of digestate from anaerobic digestion has adsorptive properties. The decoloration of the solution was achieved. A further influencing factor of the adsorption performance is the particle size. Based on the results of the preliminary tests a

  20. Carbon storage as affected by different site preparation techniques two years after mixed forest stand installation

    Energy Technology Data Exchange (ETDEWEB)

    Fonseca, F.; Figueiredo, T. de; Martins, A.

    2014-06-01

    Aim of study: This study aims at evaluating the impact of site preparation techniques prior to plantation on carbon storage and distribution in a young mixed stand of Pseudotsuga menziesii (PM) and Castanea sativa (CS). Area of study: The experimental field was established near Macedo de Cavaleiros, Northern Portugal, at 700 m elevation, mean annual temperature 12 degree centigrade and mean annual rainfall 678 mm. Material and methods: The experimental layout includes three replicates, where the different treatments corresponding to different tillage intensities were randomly distributed (high, moderate and slight intensity), in plots with an area of 375 m{sup 2} each. Twenty six months after forest stand installation, samples of herbaceous vegetation (0.49 m{sup 2} quadrat), forest species (8 PM and 8 CS) and mineral soil (at 0-5, 5-15, 15-30 and 30-60 cm depth) were collected in 15 randomly selected points in each treatment, processed in laboratory and analyzed for carbon by elemental carbon analyzer. Main results: The results obtained showed that: (i) more than 90% of the total carbon stored in the system is located in the soil, increasing in depth with tillage intensity; (ii) the contribution of herbaceous vegetation and related roots to the carbon storage is very low; (iii) the amount of carbon per tree is higher in CS than in PM; (iv) the global carbon storage was affected by soil tillage generally decreasing with the increase of tillage intensity. Accordingly, carbon storage capacity as affected by the application of different site preparation techniques should be a decision support tool in afforestation schemes. (Author)

  1. [Ultra-Fine Pressed Powder Pellet Sample Preparation XRF Determination of Multi-Elements and Carbon Dioxide in Carbonate].

    Science.gov (United States)

    Li, Xiao-li; An, Shu-qing; Xu, Tie-min; Liu, Yi-bo; Zhang, Li-juan; Zeng, Jiang-ping; Wang, Na

    2015-06-01

    The main analysis error of pressed powder pellet of carbonate comes from particle-size effect and mineral effect. So in the article in order to eliminate the particle-size effect, the ultrafine pressed powder pellet sample preparation is used to the determination of multi-elements and carbon-dioxide in carbonate. To prepare the ultrafine powder the FRITSCH planetary Micro Mill machine and tungsten carbide media is utilized. To conquer the conglomeration during the process of grinding, the wet grinding is preferred. The surface morphology of the pellet is more smooth and neat, the Compton scatter effect is reduced with the decrease in particle size. The intensity of the spectral line is varied with the change of the particle size, generally the intensity of the spectral line is increased with the decrease in the particle size. But when the particle size of more than one component of the material is decreased, the intensity of the spectral line may increase for S, Si, Mg, or decrease for Ca, Al, Ti, K, which depend on the respective mass absorption coefficient . The change of the composition of the phase with milling is also researched. The incident depth of respective element is given from theoretical calculation. When the sample is grounded to the particle size of less than the penetration depth of all the analyte, the effect of the particle size on the intensity of the spectral line is much reduced. In the experiment, when grounded the sample to less than 8 μm(d95), the particle-size effect is much eliminated, with the correction method of theoretical α coefficient and the empirical coefficient, 14 major, minor and trace element in the carbonate can be determined accurately. And the precision of the method is much improved with RSD < 2%, except Na2O. Carbon is ultra-light element, the fluorescence yield is low and the interference is serious. With the manual multi-layer crystal PX4, coarse collimator, empirical correction, X-ray spectrometer can be used to

  2. The regeneration of polluted activated carbon by radiation techniques

    Energy Technology Data Exchange (ETDEWEB)

    Wu Minghong; Bao Borong [Shanghai Institute of Nuclear Research, Academia Sinica, Shanghai (China); Zhou Ruimin; Zhu Jinliang; Hu Longxin [Shanghai University, Shanghai (China)

    1998-10-01

    In this paper, the regeneration of used activated carbon from monosodium glutamate factory was experimented using radiation and acid-alkali chemical cleaning method. Results showed that the activated carbon saturated with pollutants can be wash away easily by flushing with chemical solution prior irradiation. DSC was used to monitor the change of carbon adsorption.

  3. The Effect of Caramelization and Carbonization Temperatures toward Structural Properties of Mesoporous Carbon from Fructose with Zinc Borosilicate Activator

    Directory of Open Access Journals (Sweden)

    Tutik Setianingsih

    2014-10-01

    Full Text Available Mesoporous carbon was prepared from fructose using zinc borosilicate (ZBS activator. The synthesis involves caramelization and carbonization processes. The effect of both process temperature toward porosity and functional group of carbon surface are investigated in this research. The caramelization was conducted hydrothermally at 85 and 100 °C, followed by thermally 130 °C. The carbonization was conducted at various temperatures (450–750 °C. The carbon-ZBS composite were washed by using HF 48% solution, 1M HCl solution, and aquadest respectively to remove ZBS from the carbon. The carbon products were characterized with nitrogen gas adsorption-desorption method, FTIR spectrophotometry, X-ray diffraction, and Transmission Electron Microscopy. The highest mesopore characteristics is achieved at 100 °C (caramelization and 450 °C (carbonization, including Vmeso about 2.21 cm3/g (pore cage and 2.32 cm3/g (pore window with pore uniformity centered at 300 Å (pore cage and 200 Å (pore window, containing the surface functional groups of C=O and OH, degree of graphitization about 57% and aromaticity fraction about 0.68.

  4. Preliminary study on preparation of BCNO phosphor particles using citric acid as carbon source

    Energy Technology Data Exchange (ETDEWEB)

    Nuryadin, Bebeh W.; Pratiwi, Tripuspita; Faryuni, Irfana D.; Iskandar, Ferry, E-mail: ferry@fi.itb.ac.id; Abdullah, Mikrajuddin; Khairurrijal [Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Ganesha 10 Bandung, Indonesia 40132 (Indonesia); Ogi, Takashi; Okuyama, Kikuo [Department of Chemical Engineering, Graduate School of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi Hiroshima, Japan 739-8527 (Japan)

    2015-04-16

    A citric acid was used as a carbon source in the preparation of boron carbon oxy-nitride (BCNO) phosphor particles by a facile process. The preparation process was conducted at relatively low temperature 750 °C and at ambient pressure. The prepared BCNO phosphors showed a high photoluminescence (PL) performance at peak emission wavelength of 470 nm under excitation by a UV light 365 nm. The effects of carbon/boron and nitrogen/boron molar ratios on the PL properties were also investigated. The result showed that the emission spectra with a wavelength peak ranging from 444 nm to 496 nm can be obtained by varying carbon/boron ratios from 0.1 to 0.9. In addition, the observations showed that the BCNO phosphor material has two excitation peaks located at the 365 nm (UV) and 420 nm (blue). Based on these observations, we believe that the citric acid derived BCNO phosphor particles can be a promising inexpensive material for phosphor conversion-based white LED.

  5. Composite-alumina-carbon molecular sieve membranes prepared from novolac resin and boehmite. Part II: Effect of the carbonization temperature on the gas permeation properties

    OpenAIRE

    Llosa Tanco, Margot A.; David A. Pacheco Tanaka; Mendes, Adelio

    2015-01-01

    The influence of carbonization temperature on the permeation properties and aging of thin (4 mm) supported carbon molecular sieve membranes (c-CMSM), prepared from in house synthesized novolac phenolic resin loaded with boehmite nanoparticles, were studied. Just after membrane carbonization (fresh membrane), high permeance to N2 and O2 and low O2/ N2 permselectivities were observed; the highest permeations were observed for carbonization end temperatures between 500 C and 700 C. After leavi...

  6. Preparation of carbon-coated TiO{sub 2} nanostructures for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sang-Jun [Materials Research Center for Energy and Green Technology, Andong National University, Andong, Gyungbuk 760-745 (Korea, Republic of); Kim, Hansu [Department of Energy Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Kim, Young-Jun [Advanced Battery Research Center, Korea Electronics Technology Institute, Seongnam, Gyeonggi 463-816 (Korea, Republic of); Lee, Hyukjae, E-mail: hlee@andong.ac.kr [Materials Research Center for Energy and Green Technology, Andong National University, Andong, Gyungbuk 760-745 (Korea, Republic of)

    2011-06-01

    Highlights: > We prepare carbon-coated TiO{sub 2} nanotubes/nanowires by one-pot hydrothermal method. > Carbon coating increases electronic conductivity at higher calcination temperatures. > Carbon coating suppresses the agglomeration of nanotubes at lower calcination temperatures. - Abstract: Carbon-coated TiO{sub 2} one-dimensional nanostructures are synthesized by hydrothermal reaction followed by post-calcination at various temperatures. Post-calcination induces crystallization of TiO{sub 2} and the complete crystallization of anatase phase is observed at 600 deg. C of the calcination temperature. Carbon-coated TiO{sub 2} nanostructures show relatively poor crystallinity as compared with the pristine counterparts, but their lithiation capacity and high rate capability are improved throughout all calcination temperatures. The coated carbon suppresses severe agglomeration of TiO{sub 2} nanotubes which allows easy access of Li-ions and electrons to the whole surface of primary nanotubes, leading to the better lithiation performance. Higher calcination temperatures cause excessive growth of nanotube walls, leading to the collapse of tubular morphology and deterioration of lithiation performance. At 700 deg. C of the calcination temperature, the enhanced electronic conductivity from the graphitization of the coated carbon seems to be the main reason for the improved capacity of TiO{sub 2} nanowires.

  7. Morphology and Electrical Conductivity of Carbon Nanocoatings Prepared from Pyrolysed Polymers

    Directory of Open Access Journals (Sweden)

    Marcin Molenda

    2014-01-01

    Full Text Available Conductive carbon nanocoatings (conductive carbon layers—CCL were formed on α-Al2O3 model support using three different polymer precursors and deposition methods. This was done in an effort to improve electrical conductivity of the material through creating the appropriate morphology of the carbon layers. The best electrical properties were obtained with use of a precursor that consisted of poly-N-vinylformamide modified with pyromellitic acid (PMA. We demonstrate that these properties originate from a specific morphology of this layer that showed nanopores (3-4 nm capable of assuring easy pathways for ion transport in real electrode materials. The proposed, water mediated, method of carbon coating of powdered supports combines coating from solution and solid phase and is easy to scale up process. The optimal polymer carbon precursor composition was used to prepare conductive carbon nanocoatings on LiFePO4 cathode material. Charge-discharge tests clearly show that C/LiFePO4 composites obtained using poly-N-vinylformamide modified with pyromellitic acid exhibit higher rechargeable capacity and longer working time in a battery cell than standard carbon/lithium iron phosphate composites.

  8. Nitrate uptake improvement by modified activated carbons developed from two species of pine cones.

    Science.gov (United States)

    Nunell, G V; Fernandez, M E; Bonelli, P R; Cukierman, A L

    2015-02-15

    Activated carbons from two species of pine cones (Pinus canariensis and Cupressus sempervirens) were prepared by phosphoric acid activation and tested for the removal of nitrate ions from aqueous solution. To investigate the feasibility of improving their nitrate adsorption capacity, two different post-treatments—a thermal treatment and a treatment with saturated urea solution—were also applied to the prepared activated carbons. Comparison of the treated and untreated activated carbons showed that both post-treatments improved the nitrate adsorption performance more than twice. The maximum adsorption capacity, as evaluated from determination of the adsorption isotherms for the P. canariensis based carbons, and their proper representation by the Langmuir model, demonstrated that the post-treatment with the urea solution led to activated carbons with increased nitrate removal effectiveness, even superior to other reported results. Enhancements in their adsorption capacity could be mainly ascribed to higher contents of nitrogen and basic functional groups, whereas porous structure of the activated carbons did not seem to play a key role in the nitrate uptake. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Physical and chemical properties study of the activated carbon made from sewage sludge.

    Science.gov (United States)

    Chen, Xiaoge; Jeyaseelan, S; Graham, N

    2002-01-01

    Preparation of activated carbon from sewage sludge is a promising way to produce a useful adsorbent for pollutants removal as well as to dispose of sewage sludge. The objective of this study was to investigate the physical and chemical properties of the activated carbon made from sewage sludge so as to give a basic understanding of its structure. The activated carbon was prepared by activating anaerobically digested sewage sludge with 5 M ZnCl2 and thereafter pyrolyzing it at 500 degrees C for 2 h under nitrogen atmosphere. The properties investigated in the present study included its surface area and pore size distribution, its elemental composition and ash content, its surface chemistry structure and its surface physical morphology. Furthermore, its adsorption capacities for aqueous phenol and carbontetrachloride were examined. The results indicated that the activated carbon made from sewage sludge had remarkable micropore and mesopore surface areas and notable adsorption capacities for phenol and carbon-tetrachloride. In comparison with commercial activated carbons, it displayed distinctive physical and chemical properties.

  10. Activated carbon derived from chitosan as air cathode catalyst for high performance in microbial fuel cells

    Science.gov (United States)

    Liu, Yi; Zhao, Yong; Li, Kexun; Wang, Zhong; Tian, Pei; Liu, Di; Yang, Tingting; Wang, Junjie

    2018-02-01

    Chitosan with rich of nitrogen is used as carbon precursor to synthesis activated carbon through directly heating method in this study. The obtained carbon is activated by different amount of KOH at different temperatures, and then prepared as air cathodes for microbial fuel cells. Carbon sample treated with double amount of KOH at 850 °C exhibits maximum power density (1435 ± 46 mW m-2), 1.01 times improved, which ascribes to the highest total surface area, moderate micropore and mesoporous structure and the introduction of nitrogen. The electrochemical impedance spectroscopy and powder resistivity state that carbon treated with double amount of KOH at 850 °C possesses lower resistance. The other electrochemical measurements demonstrate that the best kinetic activity make the above treated sample to show the best oxygen reduction reaction activity. Besides, the degree of graphitization of samples increases with the activated temperature increasing, which is tested by Raman. According to elemental analysis and X-ray photoelectron spectroscopy, all chitosan samples are nitrogen-doped carbon, and high content nitrogen (pyridinic-N) improves the electrochemical activity of carbon treated with KOH at 850 °C. Thus, carbon materials derived from chitosan would be an optimized catalyst for oxygen reduction reaction in microbial fuel cell.

  11. Cellulase activity and dissolved organic carbon release from lignocellulose macrophyte-derived in four trophic conditions

    Directory of Open Access Journals (Sweden)

    Flávia Bottino

    2016-06-01

    Full Text Available Abstract Considering the importance of lignocellulose macrophyte-derived for the energy flux in aquatic ecosystems and the nutrient concentrations as a function of force which influences the decomposition process, this study aims to relate the enzymatic activity and lignocellulose hydrolysis in different trophic statuses. Water samples and two macrophyte species were collected from the littoral zone of a subtropical Brazilian Reservoir. A lignocellulosic matrix was obtained using aqueous extraction of dried plant material (≈40 °C. Incubations for decomposition of the lignocellulosic matrix were prepared using lignocelluloses, inoculums and filtered water simulating different trophic statuses with the same N:P ratio. The particulate organic carbon and dissolved organic carbon (POC and DOC, respectively were quantified, the cellulase enzymatic activity was measured by releasing reducing sugars and immobilized carbon was analyzed by filtration. During the cellulose degradation indicated by the cellulase activity, the dissolved organic carbon daily rate and enzyme activity increased. It was related to a fast hydrolysable fraction of cellulose that contributed to short-term carbon immobilization (ca. 10 days. After approximately 20 days, the dissolved organic carbon and enzyme activity were inversely correlated suggesting that the respiration of microorganisms was responsible for carbon mineralization. Cellulose was an important resource in low nutrient conditions (oligotrophic. However, the detritus quality played a major role in the lignocelluloses degradation (i.e., enzyme activity and carbon release.

  12. Interaction forces between waterborne bacteria and activated carbon particles

    NARCIS (Netherlands)

    Busscher, Henk J.; Dijkstra, Rene J. B.; Langworthy, Don E.; Collias, Dimitris I.; Bjorkquist, David W.; Mitchell, Michael D.; Van der Mei, Henny C.

    2008-01-01

    Activated carbons remove waterborne bacteria from potable water systems through attractive Lifshitz-van der Waals forces despite electrostatic repulsion between negatively charged cells and carbon surfaces. In this paper we quantify the interaction forces between bacteria with negatively and

  13. Activated Carbon Fibers For Gas Storage

    Energy Technology Data Exchange (ETDEWEB)

    Burchell, Timothy D [ORNL; Contescu, Cristian I [ORNL; Gallego, Nidia C [ORNL

    2017-01-01

    The advantages of Activated Carbon Fibers (ACF) over Granular Activated Carbon (GAC) are reviewed and their relationship to ACF structure and texture are discussed. These advantages make ACF very attractive for gas storage applications. Both adsorbed natural gas (ANG) and hydrogen gas adsorption performance are discussed. The predicted and actual structure and performance of lignin-derived ACF is reviewed. The manufacture and performance of ACF derived monolith for potential automotive natural gas (NG) storage applications is reported Future trends for ACF for gas storage are considered to be positive. The recent improvements in NG extraction coupled with the widespread availability of NG wells means a relatively inexpensive and abundant NG supply in the foreseeable future. This has rekindled interest in NG powered vehicles. The advantages and benefit of ANG compared to compressed NG offer the promise of accelerated use of ANG as a commuter vehicle fuel. It is to be hoped the current cost hurdle of ACF can be overcome opening ANG applications that take advantage of the favorable properties of ACF versus GAC. Lastly, suggestions are made regarding the direction of future work.

  14. SILOXANES REMOVAL FROM BIOGAS USING ACTIVATED CARBON

    Directory of Open Access Journals (Sweden)

    Alice Vagenknechtová

    2017-05-01

    Full Text Available SiO2 deposits which cause technical problems on combustion equipment are built by combustion of biogas containing siloxanes. Therefore, in these cases, the siloxanes must be removed from the biogas. For siloxane removal from biogas, its adsorption on activated carbon is often used. After saturation, the saturated adsorbent must be replaced. The adsorbent cost constitutes the main part of the operational costs of the purification equipment. Therefore it is necessary to find an adsorbent having high adsorption capacity for siloxane at a possible low price. Using laboratory apparatus and biogas produced from waste-water treatment sludge at the wastewater treatment plant Prague Bubenec various activated carbons were tested for siloxane removal and their adsorption capacities for siloxanes were estimated, and the adsorbent cost relative to 1 kg of siloxanes removed from biogas were calculated. The lowest price for the removal of 1 kg of siloxanes was determined by Chezacarb, Sil Extra 40 AP and 4–60 adsorbents. Another important information obtained from the test is that the weakly adsorbed siloxane (OMCTS is displaced by the larger molecule of DMCPCS during adsorption.

  15. Preparation, characterization and cytotoxicity of carbon nanotube-chitosan-phycocyanin complex

    Science.gov (United States)

    Liao, Xiaoxia; Zhang, Xuewu

    2012-01-01

    Photodynamic therapy (PDT) or photothermal therapy (PTT) using nanomaterials has shown great prospect for cancer treatment. Phycocyanin (PC) is a photoharvesting pigment and is also an attractive candidate for PDT. The multiwalled carbon nanotube (MWNT) is a potent candidate for PTT due to its extraordinary photo-to-thermal energy conversion efficiency upon excitation with near-infrared (NIR) light. To date, although MWNT-CS complexes have been well studied, no report about the reconjugation of MWNT-CS with phycocyanin is available in the literature. Here, by using water-soluble chitosan (CS), we prepared and characterized a novel biomaterial, MWNT-CS-PC, with the potential for PDT and PTT. The cytotoxicity experiments found that MWNT-CS-PC exhibited cell growth inhibition activity. Moreover, with irradiation of NIR light (808 nm) or visible light (532 nm), the photoinduced cytotoxicity was indeed enhanced. These results suggest that MWNT-CS-PC may potentially serve as a future photodynamic and photothermal therapy for cancer.

  16. Excellent Field Emission Properties of Short Conical Carbon Nanotubes Prepared by Microwave Plasma Enhanced CVD Process

    Directory of Open Access Journals (Sweden)

    Vankar Vasant

    2007-01-01

    Full Text Available AbstractRandomly oriented short and low density conical carbon nanotubes (CNTs were prepared on Si substrates by tubular microwave plasma enhanced chemical vapor deposition process at relatively low temperature (350–550 °C by judiciously controlling the microwave power and growth time in C2H2 + NH3gas composition and Fe catalyst. Both length as well as density of the CNTs increased with increasing microwave power. CNTs consisted of regular conical compartments stacked in such a way that their outer diameter remained constant. Majority of the nanotubes had a sharp conical tip (5–20 nm while its other side was either open or had a cone/pear-shaped catalyst particle. The CNTs were highly crystalline and had many open edges on the outer surface, particularly near the joints of the two compartments. These films showed excellent field emission characteristics. The best emission was observed for a medium density film with the lowest turn-on and threshold fields of 1.0 and 2.10 V/μm, respectively. It is suggested that not only CNT tip but open edges on the body also act as active emission sites in the randomly oriented geometry of such periodic structures.

  17. Pelletization of catalysts supported on activated carbon. A Case Study : clean synthesis of dimethyl carbonate from methanol and CO2

    OpenAIRE

    Orrego Romero, Andrés Felipe; Arbeláez Pérez, Oscar Felipe; Bustamante Londoño, Felipe; Villa Holguín, Aída Luz

    2016-01-01

    The synthesis of Cu-Ni bimetallic catalyst supported on pellets of activated carbon using carboxymethylcellulose (CMC) as a binder is reported. The effect of preparation conditions, such as binder concentration, AC/binder ratio, temperature, and pyrolysis heating rate on the surface area of the pellets, was evaluated. Cu and Ni metals were incorporated on the pellets by conventional incipient wetness impregnation. The support and the synthesized catalysts were characterized using N2 adsorptio...

  18. Volumetric and superficial characterization of carbon activated; Caracterizacion volumetrica y superficial de carbon activado

    Energy Technology Data Exchange (ETDEWEB)

    Carrera G, L.M.; Garcia S, I.; Jimenez B, J.; Solache R, M.; Lopez M, B.; Bulbulian G, S.; Olguin G, M.T. [Departamento de Quimica, Gerencia de Ciencias Basicas, Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2000-07-01

    The activated carbon is the resultant material of the calcination process of natural carbonated materials as coconut shells or olive little bones. It is an excellent adsorbent of diluted substances, so much in colloidal form, as in particles form. Those substances are attracted and retained by the carbon surface. In this work is make the volumetric and superficial characterization of activated carbon treated thermically (300 Centigrade) in function of the grain size average. (Author)

  19. Preparation of highly porous carbon from fir wood by KOH etching and CO2 gasification for adsorption of dyes and phenols from water.

    Science.gov (United States)

    Wu, Feng-Chin; Tseng, Ru-Ling

    2006-02-01

    Fir wood was first carbonized for 1.5 h at 450 degrees C, then soaked in a KOH solution KOH/char ratio of 1, and last activated for 1 h at 780 degrees C. During the last hour CO2 was poured in for further activation for 0, 15, 30, and 60 min, respectively. Carbonaceous adsorbents with controllable surface area and pore structure were chemically activated from carbonized fir wood (i.e., char) by KOH etching and CO2 gasification. The pore properties, including the BET surface area, pore volume, pore size distribution, and pore diameter, of these activated carbons were first characterized by the t-plot method based on N2 adsorption isotherms. Fir-wood carbon activated with CO2 gasification from 0 to 60 min exhibited a BET surface area ranging from 1371 to 2821 m2 g(-1), with a pore volume significantly increased from 0.81 to 1.73 m2 g(-1). Scanning electron microscopic (SEM) results showed that the surfaces of honeycombed holes in these carbons were significantly different from those of carbons without CO2 gasification. The adsorption of methylene blue, basic brown 1, acid blue 74, p-nitrophenol, p-chlorophenol, p-cresol, and phenol from water on all the carbons studied was examined to check their chemical characteristics. Adsorption kinetics was in agreement with the Elovich equation, and all equilibrium isotherms were in agreement with the Langmuir equation. These results were used to compare the Elovich parameter (1/b) and the adsorption quantity of the unit area (q(mon)/Sp) of activated carbons with different CO2 gasification durations. This work facilitated the preparation of activated carbon by effectively controlling pore structures and the adsorption performance of the activated carbon on adsorbates of different molecular forms.

  20. DEVELOPMENT OF ACTIVATED CARBONS FROM COAL COMBUSTION BY-PRODUCTS

    Energy Technology Data Exchange (ETDEWEB)

    Harold H. Schobert; M. Mercedes Maroto-Valer; Zhe Lu

    2003-09-30

    The increasing role of coal as a source of energy in the 21st century will demand environmental and cost-effective strategies for the use of coal combustion by-products (CCBPs), mainly unburned carbon in fly ash. Unburned carbon is nowadays regarded as a waste product and its fate is mainly disposal, due to the present lack of efficient routes for its utilization. However, unburned carbon is a potential precursor for the production of adsorbent carbons, since it has gone through a devolatilization process while in the combustor, and therefore, only requires to be activated. Accordingly, the principal objective of this work was to characterize and utilize the unburned carbon in fly ash for the production of activated carbons. The unburned carbon samples were collected from different combustion systems, including pulverized utility boilers, a utility cyclone, a stoker, and a fluidized bed combustor. LOI (loss-on-ignition), proximate, ultimate, and petrographic analyses were conducted, and the surface areas of the samples were characterized by N2 adsorption isotherms at 77K. The LOIs of the unburned carbon samples varied between 21.79-84.52%. The proximate analyses showed that all the samples had very low moisture contents (0.17 to 3.39 wt %), while the volatile matter contents varied between 0.45 to 24.82 wt%. The elemental analyses show that all the unburned carbon samples consist mainly of carbon with very little hydrogen, nitrogen, sulfur and oxygen In addition, the potential use of unburned carbon as precursor for activated carbon (AC) was investigated. Activated carbons with specific surface area up to 1075m{sup 2}/g were produced from the unburned carbon. The porosity of the resultant activated carbons was related to the properties of the unburned carbon feedstock and the activation conditions used. It was found that not all the unburned carbon samples are equally suited for activation, and furthermore, their potential as activated carbons precursors could be

  1. Autogenic reactions for preparing carbon-encapsulated, nanoparticulate TiO{sub 2} electrodes for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Pol, Vilas G.; Kang, Sun-Ho; Johnson, Christopher S.; Thackeray, Michael M. [Electrochemical Energy Storage Department, Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439 (United States); Calderon-Moreno, Jose M. [Institute of Physical Chemistry Ilie Murgulescu, Romanian Academy, 202 Splaiul Independentei St., Bucharest 060021 (Romania)

    2010-08-01

    We report an anhydrous, autogenic technique for synthesizing electronically interconnected, carbon-encapsulated, nanoparticulate anatase anode materials (TiO{sub 2}-C) for lithium-ion batteries. The TiO{sub 2}-C nanoparticles provide a reversible capacity of {proportional_to}200 mAh g{sup -1}, which exceeds the theoretical capacity of the commercially attractive spinel anode, Li{sub 4}Ti{sub 5}O{sub 12} (175 mAh g{sup -1}) and is competitive with the capacity reported for other TiO{sub 2} products. The processing method is extremely versatile and has implications for preparing, in a single step, a wide variety of electrochemically active compounds that are coated, in situ, with carbon. (author)

  2. Preparation and characterization of biomass carbon-based solid acid catalyst for the esterification of oleic acid with methanol.

    Science.gov (United States)

    Liu, Tiantian; Li, Zhilong; Li, Wei; Shi, Congjiao; Wang, Yun

    2013-04-01

    A solid acid catalyst, prepared by sulfonating carbonized corn straw, was proved to be an efficient and environmental benign catalyst for the esterification of oleic acid and methanol. Various synthetic parameters, such as carbonization temperature and time were systematically examined. It was found that the catalyst exhibited the highest acid density of 2.64 mmol/g by NaOH titration. A quantitative yield (98%) of ester was achieved, using the most active sulfonated catalyst at 333 K with a 7 wt.% catalyst/oleic acid ratio for 4h, at a 7:1 M ratio of methanol/oleic acid, while the commercial available Amberlyst-15 only gave 85% yield under the same reaction condition. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Adsorption of SO2 onto oxidized and heat-treated activated carbon fibers (ACFs)

    Science.gov (United States)

    Daley, M.A.; Mangun, C.L.; DeBarr, J.A.; Riha, S.; Lizzio, A.A.; Donnals, G.L.; Economy, J.

    1997-01-01

    A series of activated carbon fibers (ACFs) and heat-treated oxidized ACFs prepared from phenolic fiber precursors have been studied to elucidate the role of pore size, pore surface chemistry and pore volume for the adsorption of SO2 and its catalytic conversion to H2SO4.

  4. Adsorption Studies of Chromium(VI) on Activated Carbon Derived from Mangifera indica (Mango) Seed Shell

    Science.gov (United States)

    Mise, Shashikant; Patil, Trupti Nagendra

    2015-09-01

    The removal of chromium(VI) from synthetic sample by adsorption on activated carbon prepared from Mangifera indica (mango) seed shell have been carried out at room temperature 32 ± 1 °C. The removal of chromium(VI) from synthetic sample by adsorption on two types of activated carbon, physical activation and chemical activation (Calcium chloride and Sodium chloride), Impregnation Ratio's (IR) 0.25, 0.50, 0.75 for optimum time, optimum dosages and variation of pH were studied. It is observed that contact time differs for different carbons i.e. for physically and chemically activated carbons. The contact time decreases for chemically activated carbon compared to the physically activated carbon. It was observed that as dosage increases the adsorption increased along with the increase in impregnation ratio. It was also noted that as I.R. increases the surface area of Mangifera indica shell carbon increased. These dosage data were considered in the construction of isotherms and it was found that adsorption obeys Freundlich Isotherm and does not obey Langmuir Isotherm. The maximum removal of chromium (VI) was obtained in highly acidic medium at a pH of 1.50.

  5. The preparation of ethylenediamine-modified fluorescent carbon dots and their use in imaging of cells.

    Science.gov (United States)

    Dong, Wei; Zhou, Siqi; Dong, Yan; Wang, Jingwen; Ge, Xin; Sui, Lili

    2015-09-01

    In this work, fluorescent carbon dots (CDs) were synthesized using a hydrothermal method with glucose as the carbon source and were surface-modified with ethylenediamine. The properties of as-prepared CDs were analyzed by transmission electron microscopy (TEM), Fourier transform infrared (FTIR), ultraviolet-visible light (UV/vis) absorption and fluorescent spectra. Furthermore, CDs conjugated with mouse anti-(human carcinoembryonic antigen) (CEA) monoclonal antibody were successful employed in the biolabeling and fluorescent imaging of human gastric carcinoma cells. In addition, the cytotoxicity of CDs was also tested using human gastric carcinoma cells. There was no apparent cytotoxicity on human gastric carcinoma cells. These results suggest the potential application of the as-prepared CDs in bioimaging and related fields. Copyright © 2015 John Wiley & Sons, Ltd.

  6. Activated Carbon Fibers "Thickly Overgrown" by Ag Nanohair Through Self-Assembly and Rapid Thermal Annealing

    Science.gov (United States)

    Yan, Xuefeng; Xu, Sijun; Wang, Qiang; Fan, Xuerong

    2017-11-01

    Anisotropic nanomaterial-modified carbon fibers attract increasing attention because of their superior properties over traditional ones. In this study, activated carbon fibers (ACFs) "thickly overgrown" by Ag nanohair were prepared through self-assembly and rapid thermal annealing. Viscose fibers with well-dispersed silver nanoparticles (AgNPs) on surfaces were first prepared through self-assembly of hyperbranched poly(amino-amine) (HBPAA)-capped AgNPs on viscose surfaces. HBPAA endowed the AgNP surfaces with negative charges and abundant amino groups, allowing AgNPs to monodispersively self-assemble to fiber surfaces. Ag nanohair-grown ACFs were prepared by sequential pre-oxidation and carbonization. Because the carbonization furnace was open-ended, ACFs are immediately transferrable to the outside of the furnace. Therefore, the Ag liquid adsorbed by ACF pores squeezed out to form Ag nanowires through thermal contraction. FESEM characterization indicated that Ag nanohairs stood on ACF surface and grew from ACF caps. XPS and XRD characterization showed that Ag successfully assembled to fiber surfaces and retained its metallic state even after high-temperature carbonization. TG analysis suggested that Ag nanohair-grown ACFs maintained their excellent thermal stabilities. Finally, the fabricated ACFs showed excellent and durable antibacterial activities, and the developed method may provide a potential strategy for preparing metal nanowire-grown ACFs.

  7. Activated Carbon Fibers "Thickly Overgrown" by Ag Nanohair Through Self-Assembly and Rapid Thermal Annealing.

    Science.gov (United States)

    Yan, Xuefeng; Xu, Sijun; Wang, Qiang; Fan, Xuerong

    2017-11-09

    Anisotropic nanomaterial-modified carbon fibers attract increasing attention because of their superior properties over traditional ones. In this study, activated carbon fibers (ACFs) "thickly overgrown" by Ag nanohair were prepared through self-assembly and rapid thermal annealing. Viscose fibers with well-dispersed silver nanoparticles (AgNPs) on surfaces were first prepared through self-assembly of hyperbranched poly(amino-amine) (HBPAA)-capped AgNPs on viscose surfaces. HBPAA endowed the AgNP surfaces with negative charges and abundant amino groups, allowing AgNPs to monodispersively self-assemble to fiber surfaces. Ag nanohair-grown ACFs were prepared by sequential pre-oxidation and carbonization. Because the carbonization furnace was open-ended, ACFs are immediately transferrable to the outside of the furnace. Therefore, the Ag liquid adsorbed by ACF pores squeezed out to form Ag nanowires through thermal contraction. FESEM characterization indicated that Ag nanohairs stood on ACF surface and grew from ACF caps. XPS and XRD characterization showed that Ag successfully assembled to fiber surfaces and retained its metallic state even after high-temperature carbonization. TG analysis suggested that Ag nanohair-grown ACFs maintained their excellent thermal stabilities. Finally, the fabricated ACFs showed excellent and durable antibacterial activities, and the developed method may provide a potential strategy for preparing metal nanowire-grown ACFs.

  8. Preparation of ZIF-8 membranes supported on macroporous carbon tubes via a dipcoating-rubbing method

    Science.gov (United States)

    Kong, Lingyin; Zhang, Xiongfu; Liu, Haiou; Wang, Tonghua; Qiu, Jieshan

    2015-02-01

    In the present work, a new dipcoating-rubbing method (DCRM) was developed to seed the surface of a macroporous carbon tube with a mixture of graphite and ZIF-8 nanoparticles. A continuous and low-defect ZIF-8 membrane was well formed on the seeded carbon tube by solvothermal growth. The DCRM involved a two-step process including first dipcoating a thin layer of the composite of graphite and ZIF-8 nanoparticles on the carbon surface and then rubbing the layer to form a stable seed layer. The graphite in the composite acting as binding agent could have two functions: (1) anchoring the ZIF-8 seeds onto the carbon surface; (2) smoothing the coarse surface of the macroporous carbon tube, thus forming a high quality ZIF-8 membrane. The as-prepared membrane was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and single gas permeation and was proved to be continuous and low-defect. The ideal selectivity of H2/CH4 is 7.9 with a H2 permeance of 7.15×10-8 mol Pa-1 s-1 m-2, which is higher than its corresponding Knudsen diffusion value. We could therefore expect the ZIF-8 membrane supported on macroporous tubular carbon to achieve a high selectivity of H2 over CH4 through a molecular sieving effect.

  9. Mechanical, Microstructure and Surface Characterizations of Carbon Fibers Prepared from Cellulose after Liquefying and Curing

    Directory of Open Access Journals (Sweden)

    Xiaojun Ma

    2013-12-01

    Full Text Available In this study, Cellulose-based carbon fibers (CBCFs were prepared from cellulose after phenol liquefaction and curing. The characteristics and properties of CBCFs were examined by scanning electron microscopy (SEM, Fourier transform infrared spectroscopy (FTIR, X-ray diffraction (XRD, Raman spectroscopy and X-ray photoelectron spectroscopy (XPS. The results showed that, with increasing carbonization temperature, the La, Lc, and Lc/d(002 of CBCFs increased gradually, whereas the degree of disorder R decreased. The –OH, –CH2–, –O–C– and phenyl group characteristic absorption peaks of CBCFs reduced gradually. The cross-linked structure of CBCFs was converted into a graphite structure with a six-ring carbon network during carbonization. The surface of CBCFs were mainly comprised of C–C, C–O, and C=O. The tensile strength, carbonization yield and carbon content of CBCFs obtained at 1000 °C were 1015 MPa, 52%, and 95.04%, respectively.

  10. Production of Biologically Activated Carbon from Orange Peel and Landfill Leachate Subsequent Treatment Technology

    Directory of Open Access Journals (Sweden)

    Zhigang Xie

    2014-01-01

    Full Text Available In order to improve adsorption of macromolecular contaminants and promote the growth of microorganisms, active carbon for biological wastewater treatment or follow-up processing requires abundant mesopore and good biophile ability. In this experiment, biophile mesopore active carbon is produced in one-step activation with orange peel as raw material, and zinc chloride as activator, and the adsorption characteristics of orange peel active carbon is studied by static adsorption method. BET specific surface area and pore volume reached 1477 m2/g and 2.090 m3/g, respectively. The surface functional groups were examined by Fourier transform infrared spectroscopy (FT-IR. The surface of the as-prepared activated carbon contained hydroxyl group, carbonyl group, and methoxy group. The analysis based on X-ray diffraction spectrogram (XRD and three-dimensional fluorescence spectrum indicated that the as-prepared activated carbon, with smaller microcrystalline diameter and microcrystalline thickness and enhanced reactivity, exhibited enhanced adsorption performance. This research has a deep influence in effectively controlling water pollution, improving area water quality, easing orange peel waste pollution, and promoting coordinated development among society, economy, and environment.

  11. Conducting nanocomposites based on Polyamide 66 and Carbon Nanofibers prepared by cryogenic grinding

    OpenAIRE

    2011-01-01

    Abstract Nanocomposites based on polyamide 6,6 and carbon nanofiber have been obtained following a new procedure. It consists of the physical mixing of the polymer matrix, in the form of powder, and the corresponding amount of additive. Then, samples were prepared by compression moulding and their structural characteristics, as well as their thermal and electrical properties were determined. The materials present good electrical conductivity at lower percolation thresholds than tho...

  12. Preparation and Performance Evaluation of Biochars from Neem Seed Active Substance Extracted Residues (NSASER)

    Science.gov (United States)

    Li, Jialei; Lu, Shuwen

    2017-05-01

    Neem seed active substance extracted residues (NSASER) is industrial by-product, which is often discarded as a waste. It would lead to a certain degree of harm to the environment. The aim of this study was to prepare the biochars with neem seed active substance extracted residues (NSASER) under the anaerobic pyrolysis conditions. The pyrolysis process was studied with different pyrolysis power (200W, 500W, 800W, 1100W and 1400W), and the performance of the prepared biochars was evaluated. The results showed that the required time was to complete the pyrolysis process that gradually decreased with pyrolysis power increased from 200 to 1400 W, and the final pyrolysis temperature was to complete the pyrolysis process that increased with pyrolysis power increased from 200 to 1400 W. The biochars yield decreased with pyrolysis power increased from 200 to 1400 W, and the biochars yield has the maximum value when the pyrolysis power was of 200W. And the prepared biochars still had some characteristics of the plant cell and kept uniform porous structure, which was beneficial to absorb the small molecule substance. The water content of the prepared biochars was 7.18±0.53, the ash content of the prepared biochars was 5.92±0.31 and the fixed carbon content of the prepared biochars was 81.27±0.89. Compared with the bamboo charcoal, the performance index of the prepared biochars was in according with National Standard of the People’s Republic of China GBT26913-2011 of the bamboo charcoal. The prepared biochars had a potential value in application.

  13. Activated Carbon Composites for Air Separation

    Energy Technology Data Exchange (ETDEWEB)

    Baker, Frederick S [ORNL; Contescu, Cristian I [ORNL; Tsouris, Costas [ORNL; Burchell, Timothy D [ORNL

    2011-09-01

    Coal-derived synthesis gas is a potential major source of hydrogen for fuel cells. Oxygen-blown coal gasification is an efficient approach to achieving the goal of producing hydrogen from coal, but a cost-effective means of enriching O2 concentration in air is required. A key objective of this project is to assess the utility of a system that exploits porous carbon materials and electrical swing adsorption to produce an O2-enriched air stream for coal gasification. As a complement to O2 and N2 adsorption measurements, CO2 was used as a more sensitive probe molecule for the characterization of molecular sieving effects. To further enhance the potential of activated carbon composite materials for air separation, work was implemented on incorporating a novel twist into the system; namely the addition of a magnetic field to influence O2 adsorption, which is accompanied by a transition between the paramagnetic and diamagnetic states. The preliminary findings in this respect are discussed.

  14. Electrospinning Preparation and Photocatalytic Activity of Porous TiO2 Nanofibers

    Directory of Open Access Journals (Sweden)

    Shanhu Liu

    2012-01-01

    Full Text Available Porous TiO2 nanofibers were prepared via a facile electrospinning method. The carbon nanospheres were mixed with the ethanol solution containing both poly(vinylpyrrolidone and titanium tetraisopropoxide for electrospinning; and subsequent calcination of as-spun nanofibers led to thermal decomposition of carbon nanospheres, leaving behind pores in the TiO2 nanofibers. The morphology and phase structure of the products were investigated with scanning electron microscopy (SEM, transmission electron microscopy (TEM, and X-ray diffraction (XRD. Furthermore, the photocatalytic activity of porous TiO2 nanofibers was evaluated by photodecomposition of methylene blue under UV light. Results showed that the porous TiO2 nanofibers have higher surface area and enhanced photocatalysis activity, compared to nonporous TiO2 nanofibers.

  15. Fabrication And Properties Of Silver Based Multiwall Carbon Nanotube Composite Prepared By Spark Plasma Sintering Method

    Directory of Open Access Journals (Sweden)

    Lis M.

    2015-06-01

    Full Text Available The paper presents results of investigations of the obtained nanocomposite materials based on silver with addition of multiwall carbon nanotubes. The powder of carbon nanotubes content from 0.1 to 3 wt. % was produced by application of powder metallurgy methods, through mixing and high-energetic milling, and also chemical methods. Modification of carbon nanotubes included electroless deposition of silver particles on the carbon nanotube active surfaces and chemical reduction with strong reducing agent – sodium borohydride (NaBH4. The obtained powder mixtures were consolidated by SPS – Spark Plasma Sintering method. The formed composites were subjected to tests of relative density, electrical conductivity and electro-erosion properties. Detailed examinations of the structure with application of X-ray microanalysis, with consideration of carbon nanotubes distribution, were also carried out. The effect of manufacturing methods on properties of the obtained composites was observed.

  16. Correlation study of nanocrystalline carbon doped thin films prepared by a thermionic vacuum arc deposition technique

    Science.gov (United States)

    Dinca-Balan, Virginia; Vladoiu, Rodica; Mandes, Aurelia; Prodan, Gabriel

    2017-11-01

    The synthesis of Ag, Mg and Si nanocrystalline, embedded in a hydrogen-free amorphous carbon (a-C) matrix, deposited by a high vacuum and free buffer gas technique, were investigated. The films with compact structures and extremely smooth surfaces were prepared using the thermionic vacuum arc method in one electron gun configuration, on glass and silicon substrates. The surface morphology and wettability of the obtained multifunctional thin films were investigated using transmission electron microscopy (TEM), scanning electron microscopy (SEM) and free surface energy (FSE) by See System. The results from the TEM measurements show how the Ag, Mg and Si interacted with carbon and the influence these materials have on the thin film structure formation and the grain size distribution. SEM correlated with EDX results reveal a very precise comparative study, regarding the quantity of the elements that morphed into carbides nanostructures. Also, the FSE results prove how different materials in combination with carbon can make changes to the surface properties.

  17. Nonlinear optical properties measurement of polypyrrole -carbon nanotubes prepared by an electrochemical polymerization method

    Directory of Open Access Journals (Sweden)

    Shahriari

    2017-02-01

    Full Text Available In this work, the optical properties dependence of Multi-Walled Carbon Nanotubes (MWNT on concentration was discussed. MWNT samples were prepared in polypyrrole by an electrochemical polymerization of monomers, in the presence of different concentrations of MWNTs, using Sodium Dodecyl-Benzen-Sulfonate (SDBS as surfactant at room temperature. The nonlinear refractive and nonlinear absorbtion indices were measured using a low power CW laser beam operated at 532 nm using z-scan method. The results show that nonlinear refractive and nonlinear absorbtion indices tend to be increased with increasing the concentration of carbon nanotubes. Optical properties of  carbone nanotubes indicate that they are good candidates for nonlinear optical devices

  18. Carbon aerogel composites prepared by ambient drying and using oxidized polyacrylonitrile fibers as reinforcements.

    Science.gov (United States)

    Feng, Junzong; Zhang, Changrui; Feng, Jian; Jiang, Yonggang; Zhao, Nan

    2011-12-01

    Carbon fiber-reinforced carbon aerogel composites (C/CAs) for thermal insulators were prepared by copyrolysis of resorcinol-formaldehyde (RF) aerogels reinforced by oxidized polyacrylonitrile (PAN) fiber felts. The RF aerogel composites were obtained by impregnating PAN fiber felts with RF sols, then aging, ethanol exchanging, and drying at ambient pressure. Upon carbonization, the PAN fibers shrink with the RF aerogels, thus reducing the difference of shrinkage rates between the fiber reinforcements and the aerogel matrices, and resulting in C/CAs without any obvious cracks. The three point bend strength of the C/CAs is 7.1 ± 1.7 MPa, and the thermal conductivity is 0.328 W m(-1) K(-1) at 300 °C in air. These composites can be used as high-temperature thermal insulators (in inert atmospheres or vacuum) or supports for phase change materials in thermal protection system. © 2011 American Chemical Society

  19. Reuse performance of granular-activated carbon and activated carbon fiber in catalyzed peroxymonosulfate oxidation.

    Science.gov (United States)

    Yang, Shiying; Li, Lei; Xiao, Tuo; Zhang, Jun; Shao, Xueting

    2017-03-01

    Recently, activated carbon was investigated as an efficient heterogeneous metal-free catalyst to directly activate peroxymonosulfate (PMS) for degradation of organic compounds. In this paper, the reuse performance and the possible deactivation reasons of granular-activated carbon (GAC) and activated carbon fiber (ACF) in PMS activation were investigated. As results indicated, the reusability of GAC, especially in the presence of high PMS dosage, was relatively superior to ACF in catalyzed PMS oxidation of Acid Orange 7 (AO7), which is much more easily adsorbed by ACF than by GAC. Pre-oxidation experiments were studied and it was demonstrated that PMS oxidation on ACF would retard ACF's deactivation to a big extent. After pre-adsorption with AO7, the catalytic ability of both GAC and ACF evidently diminished. However, when methanol was employed to extract the AO7-spent ACF, the catalytic ability could recover quite a bit. GAC and ACF could also effectively catalyze PMS to degrade Reactive Black 5 (RB5), which is very difficult to be adsorbed even by ACF, but both GAC and ACF have poor reuse performance for RB5 degradation. The original organic compounds or intermediate products adsorbed by GAC or ACF would be possibly responsible for the deactivation.

  20. Synthesis and characterization of nanocomposites based on PANI and carbon nanostructures prepared by electropolymerization

    Energy Technology Data Exchange (ETDEWEB)

    Petrovski, Aleksandar; Paunović, Perica [Faculty of Technology and Metallurgy, SS Cyril and Methodius University, Rudjer Bošković, 16, 1000, Skopje (Macedonia, The Former Yugoslav Republic of); Avolio, Roberto; Errico, Maria E.; Cocca, Mariacristina; Gentile, Gennaro [Institute for Polymers, Composites and Biomaterials, National Research Council, Via Campi Flegrei 34, 80078, Pozzuoli, Napoli (Italy); Grozdanov, Anita, E-mail: anita.grozdanov@yahoo.com [Faculty of Technology and Metallurgy, SS Cyril and Methodius University, Rudjer Bošković, 16, 1000, Skopje (Macedonia, The Former Yugoslav Republic of); Avella, Maurizio [Institute for Polymers, Composites and Biomaterials, National Research Council, Via Campi Flegrei 34, 80078, Pozzuoli, Napoli (Italy); Barton, John [Tyndall National Institute, University College Cork, Dyke Parade, T12 R5CP, Cork (Ireland); Dimitrov, Aleksandar [Faculty of Technology and Metallurgy, SS Cyril and Methodius University, Rudjer Bošković, 16, 1000, Skopje (Macedonia, The Former Yugoslav Republic of)

    2017-01-01

    Nanocomposites based on polyaniline (PANI) and carbon nanostructures (CNSs) (graphene (G) and multiwall carbon nanotubes (MWCNTs)) were prepared by in situ electrochemical polymerization. CNSs were inserted into the PANI matrix by dispersing them into the electrolyte before the electropolymerization. Electrochemical characterization by means of cyclic voltammetry and steady state polarization were performed in order to determine conditions for electro-polymerization. Electro-polymerization of the PANI based nanocomposites was carried out at 0.75 V vs. saturated calomel electrode (SCE) for 40 and 60 min. The morphology and structural characteristics of the obtained nanocomposites were studied by scanning electron microscopy (SEM) and Raman spectroscopy, while thermal stability was determined using thermal gravimetric analysis (TGA). According to the morphological and structural study, fibrous and porous structure of PANI based nanocomposites was detected well embedding both G and MWCNTs. Also, strong interaction between quinoidal structure of PANI with carbon nanostructures via π–π stacking was detected by Raman spectroscopy. TGA showed the increased thermal stability of composites reinforced with CNSs, especially those reinforced with graphene. - Highlights: • Nanocomposites of PANI with carbon nanostructures were prepared for sensing application. • By cyclic voltammetry, conductive form of PANI (green colored emeraldine phase) is obtained 0.75 V • Using 4 Probe method, nanocomposite PANI/CNS tablet was tested for sensing application. • Micro-structural properties of nanocomposites were studied by SEM, TGA and Raman analysis.

  1. Mercury Emissions Capture Efficiency with Activated Carbon ...

    Science.gov (United States)

    This EPA-led project, conducted in collaboration with UNEP, the Swedish Environmental Institute and various Russian Institutes, that demonstrates that the mercury emission control efficiencies of activated carbon injection technologies applied at a Russian power plant burning Russian coals are similar to those found at U.S. plants burning US coals. (The US funding was from funds provided to the EPA by the Department of State pursuant to the Bio-Chemical Redirect Program which engages former Russian (and other former Soviet) weapons scientists in research projects with US collaborators.) Among other things, this report will aid the major task, of developing guidance on best available mercury control technology/best environmental practices (BAT/BEP) for coal-fired power plants, a major source a global anthropogenic emissions. (The new Minamata Convention requires BAT/BEP for new power plants and other major emission sources within five years of treaty ratification.)

  2. Comparisons of porous and adsorption properties of carbons activated by steam and KOH.

    Science.gov (United States)

    Wu, Feng-Chin; Tseng, Ru-Ling; Juang, Ruey-Shin

    2005-03-01

    In this work, fir woods and pistachio shells were used as source materials to prepare porous carbons, which were activated by physical (steam) and chemical (KOH) methods. Pore properties of these activated carbons including the BET surface area, pore volume, pore size distribution, and pore diameter were first characterized by a t-plot method based on N(2) adsorption isotherms. Highly porous activated carbons with BET surface area up to 1009-1096 m(2)/g were obtained. The steam and KOH activation methods produced carbons with mesopore content in the range 9-15 and 33-49%, respectively. The adsorption equilibria and kinetics of tannic acid, methylene blue, 4-chlorophenol, and phenol from water on such carbons at 30 degrees C were then investigated to check their chemical characteristics. The Freundlich equation gave a better fit to all adsorption isotherms than the Langmuir equation. On the other hand, the intraparticle diffusion model could best follow all adsorption processes. In comparison with KOH-activated carbons, it was shown that the rate of external surface adsorption with steam-activated carbons was significantly higher but the rate of intraparticle diffusion was much lower.

  3. Relationship between Plasma Parameters and Carbon Atom Coordination in a-C:H Films Prepared by RF Glow Discharge Decomposition

    Science.gov (United States)

    Yamamoto, Kenji; Ichikawa, Yosuke; Nakayama, Takehisa; Tawada, Yoshihisa

    1988-08-01

    Amorphous C:H films were prepared by rf glow discharge decomposition from CH4 using a permanent magnet system to apply a static magnetic field perpendicular to the rf electric field. The structure and properties of a-C:H films have been investigated systematically with respect to the hydrogen content, hardness and coordination of carbon atoms as a function of rf power (self-bias voltage). The coordination of carbon atoms has been determined by solid-state 13C magic angle spinning nuclear magnetic resonance measurements. It is found that the fraction of graphitic (sp2) versus tetrahedral (sp3) bonding increases with increasing rf power (negative self-bias voltage). Film hardness is understood in terms of the balance between the incorporated hydrogen and the fraction of graphitic (sp2) versus tetrahedral (sp3) bonding. The production of ionic and neutral species from a glow discharge has also been monitored by mass spectroscopy and optical emission spectroscopy to investigate the relation between plasma parameters and carbon atom coordination. Using these measurements and negative self-bias measurements, it is shown that the coordination of carbon atoms is determined not only by the energy of impinging ions on the substrate but also by the type of active species. In addition, the neutral and ionic C2H2 related species are thought to be some of the species which increase the fraction of graphitic (sp2) versus tetrahedral (sp3) bonding.

  4. Electrical, thermal and electrochemical properties of disordered carbon prepared from palygorskite and cane molasses

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez, Edelio Danguillecourt, E-mail: edelioalvarez42@gmail.com [Instituto Superior Minero Metalúrgico (ISMM), Moa 83300 (Cuba); Laffita, Yodalgis Mosqueda, E-mail: yodalgis@imre.uh.cu [Institute of Materials Science and Technology-Havana University, La Habana 10400 (Cuba); Montoro, Luciano Andrey, E-mail: landrey.montoro@gmail.com [Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais 31270-901 (Brazil); Della Santina Mohallem, Nelcy, E-mail: nelcydsm@gmail.com [Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais 31270-901 (Brazil); Cabrera, Humberto, E-mail: hcabrera@ictp.it [SPIE-ICTP Anchor Research in Optics Program Laboratory, International Centre for Theoretical Physics (ICTP), Strada Costiera 11, Trieste 34151 (Italy); Centro Multidisciplinario de Ciencias, Instituto Venezolano de Investigaciones Científicas (IVIC), 5101 Mérida (Venezuela, Bolivarian Republic of); Pérez, Guillermo Mesa, E-mail: guille@ceaden.edu.cu [National Center for Technological Research (CEADEN), La Habana 10400 (Cuba); Frutis, Miguel Aguilar, E-mail: mafrutis@yahoo.es [CICATA-IPN, Legaria 694, Col. Irrigacion, Del., Miguel Hidalgo CP 11500 (Mexico); Cappe, Eduardo Pérez, E-mail: cappe@imre.uh.cu [Institute of Materials Science and Technology-Havana University, La Habana 10400 (Cuba)

    2017-02-15

    We have synthesized and electrochemically tested a carbon sample that was suitable as anode for lithium secondary battery. The synthesis was based on the use of the palygorskite clay as template and sugar cane molasses as carbon source. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, Brunauer–Emmett–Teller (BET) measurements and High Resolution Transmission Electron Microscope (HRTEM) analysis showed that the nanometric carbon material has a highly disordered graphene-like wrinkled structure and large specific surface area (467 m{sup 2} g{sup −1}). The compositional characterization revealed a 14% of heteroatoms-containing groups (O, H, N, S) doping the as-prepared carbon. Thermophysical measurements revealed the good thermal stability and an acceptable thermal diffusivity (9·10{sup −7} m{sup 2} s{sup −1}) and conductivity (1.1 W m{sup −1} K{sup −1}) of this carbon. The electrical properties showed an electronic conductivity of hole-like carriers of approximately one S/cm in a 173–293 K range. The testing of this material as anodes in a secondary lithium battery displayed a high specific capacity and excellent performance in terms of number of cycles. A high reversible capacity of 356 mA h g{sup −1} was reached. - Graphical abstract: TEM image and electrochemistry behavior of a new graphene oxide-like carbon. - Highlights: • A high disordered graphene oxide-like conducting carbon is reported. • The synthesis was based on palygorskite and sugar cane molasses as precursors. • The disordered conducting carbon is composed of doped- graphene heterogeneous domains. • This material combines a large specific surface area and high electric conductivity. • The thermophysical and electrochemical properties of this material reveal adequate behavior.

  5. Single and Mixed Gas Adsorption Equilibria of Carbon Dioxide/Methane on Activated Carbon

    NARCIS (Netherlands)

    van der Vaart, R.; van der Vaart, Rick; Huiskes, Cindy; Bosch, H.; Reith, T.

    2000-01-01

    Single gas adsorption isotherms of methane and carbon dioxide on micro-porous Norit RB1 activated carbon were determined in a gravimetric analyser in the temperature range of 292 to 349 K and pressures to 0.8 Mpa. Furthermore binary isotherms of carbon dioxide and methane mixtures were determined at

  6. THE ROLE OF ACTIVATED CARBON IN SOLVING ECOLOGICAL PROBLEMS

    Directory of Open Access Journals (Sweden)

    V. M. Mukhin

    2008-06-01

    Full Text Available The authors present a brief analysis of the current global situation concerning the utilization of activated carbon in various fields. The article presents data concerning the synthesis and adsorption and structure properties of new activated carbons, used for solving ecological problems. The authors investigated the newly obtained activated carbons in comparison with several AC marks known in the world. It has been shown that currently synthesized AC are competitive with foreign marks.

  7. HYDROGEN SULFIDE ADSORPTION BY ALKALINE IMPREGNATED COCONUT SHELL ACTIVATED CARBON

    Directory of Open Access Journals (Sweden)

    HUI SUN CHOO

    2013-12-01

    Full Text Available Biogas is one type of renewable energy which can be burnt to produce heat and electricity. However, it cannot be burnt directly due to the presence of hydrogen sulfide (H2S which is highly corrosive to gas engine. In this study, coconut shell activated carbon (CSAC was applied as a porous adsorbent for H2S removal. The effect of amount of activated carbon and flow rate of gas stream toward adsorption capacity were investigated. Then, the activated carbons were impregnated by three types of alkaline (NaOH, KOH and K2CO3 with various ratios. The effects of various types of alkaline and their impregnation ratio towards adsorption capacity were analysed. In addition, H2S influent concentration and the reaction temperature on H2S adsorption were also investigated. The result indicated that adsorption capacity increases with the amount of activated carbon and decreases with flow rate of gas stream. Alkaline impregnated activated carbons had better performance than unimpregnated activated carbon. Among all impregnated activated carbons, activated carbon impregnated by K2CO3 with ratio 2.0 gave the highest adsorption capacity. Its adsorption capacity was 25 times higher than unimpregnated activated carbon. The result also indicated that the adsorption capacity of impregnated activated carbon decreased with the increment of H2S influent concentration. Optimum temperature for H2S adsorption was found to be 50˚C. In this study, the adsorption of H2S on K2CO3 impregnated activated carbon was fitted to the Langmuir isotherm. The fresh and spent K2CO3 impregnated activated carbon were characterized to study the adsorption process.

  8. Preparation of Labeled Aflatoxins with High Specific Activities

    Science.gov (United States)

    Hsieh, D. P. H.; Mateles, R. I.

    1971-01-01

    Resting cells of Aspergillus parasiticus ATCC 15517 were used to prepare highly labeled aflatoxins from labeled acetate. High synthetic activity in growing cells was evidenced only during 40 to 70 hr of incubation. Glucose was required for high incorporation efficiency, whereas the concentration of the labeled acetate determined the specific activity of the product. When labeled acetate was continuously added to maintain a concentration near but not exceeding 10 mm, in a culture containing 30 g of glucose per liter, 2% of its labels could be recovered in the purified aflatoxins which have a specific activity more than three times that of the labeled acetate. PMID:4329435

  9. Materialographic preparation of lithium-carbon intercalation compounds; Materialographische Praeparation von Lithium-Kohlenstoff-Einlagerungsverbindungen

    Energy Technology Data Exchange (ETDEWEB)

    Druee, Martin; Seyring, Martin; Grasemann, Aaron [Jena Univ. (Germany). Otto Schott Institute of Materials Research; Rettenmayr, Markus [Center for Energy and Environmental Chemistry, Jena (Germany)

    2016-12-15

    The materialographic investigation of anode materials for rechargeable lithium ion batteries is a significant step in the understanding and development of electrode materials, but made dramatically more difficult due to the high reactivity of the materials involved. In this work a method is presented which permits the metallographic preparation of the lithium-carbon intercalation compounds used as anode materials in today's rechargeable lithium ion batteries, and which allows the details of their microstructures to be contrasted. After classic, but absolutely water free, preparation in a protective gas atmosphere, the final stage of preparation is carried out using both ion beam polishing and manual polishing on a stationary polishing disc, whereby no significant differences of the quality of the microstructural images obtained is apparent.

  10. Preparation of Magnetic Carbon Nanotubes (Mag-CNTs) for Biomedical and Biotechnological Applications

    Science.gov (United States)

    Masotti, Andrea; Caporali, Andrea

    2013-01-01

    Carbon nanotubes (CNTs) have been widely studied for their potential applications in many fields from nanotechnology to biomedicine. The preparation of magnetic CNTs (Mag-CNTs) opens new avenues in nanobiotechnology and biomedical applications as a consequence of their multiple properties embedded within the same moiety. Several preparation techniques have been developed during the last few years to obtain magnetic CNTs: grafting or filling nanotubes with magnetic ferrofluids or attachment of magnetic nanoparticles to CNTs or their polymeric coating. These strategies allow the generation of novel versatile systems that can be employed in many biotechnological or biomedical fields. Here, we review and discuss the most recent papers dealing with the preparation of magnetic CNTs and their application in biomedical and biotechnological fields. PMID:24351838

  11. Continuous Preparation of Copper/Carbon Nanotube Composite Films and Application in Solar Cells.

    Science.gov (United States)

    Luo, Xiao Gang; Le Wu, Min; Wang, Xiao Xia; Zhong, Xin Hua; Zhao, Ke; Wang, Jian Nong

    2016-02-08

    Realizing the continuous and large scale preparation of particle/carbon nanotube (CNT) composites with enhanced functionalities, and broad applications in energy conversion, harvesting, and storage systems, remains as a big challenge. Here, we report a scalable strategy to continuously prepare particle/CNT composite films in which particles are confined by CNT films. This is achieved by the continuous condensation and deposition of a cylindrical assembly of CNTs on a paper strip and the in situ incorporation of particles during the layer-by-layer deposition process. A Cu/CNT composite film is prepared as an example; such a film exhibits very high power conversion efficiency when it is used as a counter electrode in a solar cell, compared with previous materials under otherwise identical conditions. The proposed method can be extended to other CNT-based composite films with excellent functionalities for wide applications. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Preparation of magnetic carbon nanotubes (Mag-CNTs) for biomedical and biotechnological applications.

    Science.gov (United States)

    Masotti, Andrea; Caporali, Andrea

    2013-12-18

    Carbon nanotubes (CNTs) have been widely studied for their potential applications in many fields from nanotechnology to biomedicine. The preparation of magnetic CNTs (Mag-CNTs) opens new avenues in nanobiotechnology and biomedical applications as a consequence of their multiple properties embedded within the same moiety. Several preparation techniques have been developed during the last few years to obtain magnetic CNTs: grafting or filling nanotubes with magnetic ferrofluids or attachment of magnetic nanoparticles to CNTs or their polymeric coating. These strategies allow the generation of novel versatile systems that can be employed in many biotechnological or biomedical fields. Here, we review and discuss the most recent papers dealing with the preparation of magnetic CNTs and their application in biomedical and biotechnological fields.

  13. Preparation of Magnetic Carbon Nanotubes (Mag-CNTs for Biomedical and Biotechnological Applications

    Directory of Open Access Journals (Sweden)

    Andrea Masotti

    2013-12-01

    Full Text Available Carbon nanotubes (CNTs have been widely studied for their potential applications in many fields from nanotechnology to biomedicine. The preparation of magnetic CNTs (Mag-CNTs opens new avenues in nanobiotechnology and biomedical applications as a consequence of their multiple properties embedded within the same moiety. Several preparation techniques have been developed during the last few years to obtain magnetic CNTs: grafting or filling nanotubes with magnetic ferrofluids or attachment of magnetic nanoparticles to CNTs or their polymeric coating. These strategies allow the generation of novel versatile systems that can be employed in many biotechnological or biomedical fields. Here, we review and discuss the most recent papers dealing with the preparation of magnetic CNTs and their application in biomedical and biotechnological fields.

  14. Activation of polymer blend carbon nanofibres by alkaline hydroxides and their hydrogen storage performances

    Energy Technology Data Exchange (ETDEWEB)

    Suarez-Garcia, F.; Vilaplana-Ortego, E.; Kunowsky, M.; Linares-Solano, A. [Grupo de Materiales Carbonosos y Medio Ambiente, Departamento de Quimica Inorganica, Universidad de Alicante, E-03080 Alicante (Spain); Kimura, M. [Gun Ei Chemical Ind. Co., Ltd., Takasaki, Gunma 370-0032 (Japan); Oya, A. [Graduate School of Engineering, Gunma University, Gunma 376-8515 (Japan)

    2009-11-15

    In the present work we study the hydroxide activation (NaOH and KOH) of phenol-formaldehyde resin derived CNFs prepared by a polymer blend technique to prepare highly porous activated carbon nanofibres (ACNFs). Morphology and textural characteristics of these ACNFs were studied and their hydrogen storage capacities at 77 K (at 0.1 MPa and at high pressures up to 4 MPa) were assessed, and compared, with reported capacities of other porous carbon materials. Phenol-formaldehyde resin derived carbon fibres were successfully activated with these two alkaline hydroxides rendering highly microporous ACNFs with reasonable good activation process yields up to 47 wt.% compared to 7 wt.% yields from steam activation for similar surface areas of 1500 m{sup 2}/g or higher. These nano-sized activated carbons present interesting H{sub 2} storage capacities at 77 K which are comparable, or even higher, to other high quality microporous carbon materials. This observation is due, in part, to their nano-sized diameters allowing to enhance their packing densities to 0.71 g/cm{sup 3} and hence their resulting hydrogen storage capacities. (author)

  15. Production and characterization of activated carbon from a ...

    African Journals Online (AJOL)

    In this study, the use of a bituminous coal for the production of activated carbons with chemical activation was investigated. The effects of process variables such as chemical reagents, activation temperature, impregnation ratio and carbonization temperature were investigated to optimize these parameters. The resultant ...

  16. Nitrogen-Doped Carbon Nanoparticles for Oxygen Reduction Prepared via a Crushing Method Involving a High Shear Mixer

    Directory of Open Access Journals (Sweden)

    Lei Shi

    2017-09-01

    Full Text Available The disposal of agricultural wastes such as fresh banana peels (BPs is an environmental issue. In this work, fresh BPs were successfully transformed into nitrogen-doped carbon nanoparticles (N-CNPs by using a high shear mixer facilitated crushing method (HSM-FCM followed by carbonization under Ar atmosphere. Ammonia-activated N-CNPs (N-CNPs-NH3 were prepared via subsequent ammonia activation treatments at a high temperature. The as-prepared N-CNPs and N-CNPs-NH3 materials both exhibited high surface areas (above 700 m2/g and mean particle size of 50 nm. N-CNPs-NH3 showed a relatively higher content of pyridinic and graphitic N compared to N-CNPs. In alkaline media, N-CNPs-NH3 showed superior performances as an oxygen reduction reaction (ORR catalyst (E0 = −0.033 V, J = 2.4 mA/cm2 compared to N-CNPs (E0 = 0.07 V, J = 1.8 mA/cm2. In addition, N-CNPs-NH3 showed greater oxygen reduction stability and superior methanol crossover avoidance than a conventional Pt/C catalyst. This study provides a novel, simple, and scalable approach to valorize biomass wastes by synthesizing highly efficient electrochemical ORR catalysts.

  17. Effect of commercial activated carbons in sulfur cathodes on the electrochemical properties of lithium/sulfur batteries

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jin-Woo; Kim, Icpyo [School of Materials Science and Engineering, Gyeongsang National University, 501 Jinju-daero, Jinju, Gyeongnam 52828 (Korea, Republic of); Kim, Ki-Won; Nam, Tae-Hyun; Cho, Kwon-Koo; Ahn, Jou-Hyeon [Department of Materials Engineering and Convergence Technology, Gyeongsang National University, 501 Jinju-daero, Jinju, Gyeongnam 52828 (Korea, Republic of); Ryu, Ho-Suk [Department of Material and Energy Engineering, Gyeongwoon University, 730, Gangdong-ro, Sandong-myeon, Gumi, Gyeongbuk, 39160 (Korea, Republic of); Ahn, Hyo-Jun, E-mail: ahj@gnu.ac.kr [School of Materials Science and Engineering, Gyeongsang National University, 501 Jinju-daero, Jinju, Gyeongnam 52828 (Korea, Republic of); Department of Materials Engineering and Convergence Technology, Gyeongsang National University, 501 Jinju-daero, Jinju, Gyeongnam 52828 (Korea, Republic of)

    2016-10-15

    Highlights: • The sulfur/activated carbon composite is fabricated using commercial activated carbons. • The sulfur/activated carbon composite with coal shows the best performance. • The Li/S battery has capacities of 1240 mAh g{sup −1} at 1 C and 567 mAh g{sup −1} at 10 C. - Abstract: We prepared sulfur/active carbon composites via a simple solution-based process using the following commercial activated carbon-based materials: coal, coconut shells, and sawdust. Although elemental sulfur was not detected in any of the sulfur/activated carbon composites based on Thermogravimetric analysis, X-ray diffraction, and Raman spectroscopy, Energy-dispersive X-ray spectroscopy results confirmed its presence in the activated carbon. These results indicate that sulfur was successfully impregnated in the activated carbon and that all of the activated carbons acted as sulfur reservoirs. The sulfur/activated carbon composite cathode using coal exhibited the highest discharge capacity and best rate capability. The first discharge capacity at 1 C (1.672 A g{sup −1}) was 1240 mAh g{sup −1}, and a large reversible capacity of 567 mAh g{sup −1} was observed at 10 C (16.72 A g{sup −1}).

  18. Modulation of sensory and motor cortex activity during speech preparation.

    Science.gov (United States)

    Mock, Jeffrey R; Foundas, Anne L; Golob, Edward J

    2011-03-01

    Previous studies have shown that speaking affects auditory and motor cortex responsiveness, which may reflect the influence of motor efference copy. If motor efference copy is involved, it would also likely influence auditory and motor cortical activity when preparing to speak. We tested this hypothesis by using auditory event-related potentials and transcranial magnetic stimulation (TMS) of the motor cortex. In the speech condition subjects were visually cued to prepare a vocal response to a subsequent target, which was compared to a control condition without speech preparation. Auditory and motor cortex responsiveness at variable times between the cue and target were probed with an acoustic stimulus (Experiment 1, tone or consonant-vowels) or motor cortical TMS (Experiment 2). Acoustic probes delivered shortly before targets elicited a fronto-central negative potential in the speech condition. Current density analysis showed that auditory cortical activity was attenuated at the beginning of the slow potential in the speech condition. Sensory potentials in response to probes had shorter latencies (N100) and larger amplitudes (P200) when consonant-vowels matched the sound of cue words. Motor cortex excitability was greater in the speech than in the control condition at all time points before picture onset. The results suggest that speech preparation induces top-down regulation of sensory and motor cortex responsiveness, with different time courses for auditory and motor systems. © 2011 The Authors. European Journal of Neuroscience © 2011 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

  19. Preparation and Properties of Alkali Activated Metakaolin-Based Geo