Journal articles: 'Carbon'

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Zolotareva, O. K. "BIOCATALYTIC CARBON DIOXIDE CAPTURE PROMOTED BY CARBONIC ANHYDRASE." Biotechnologia Acta 16, no. 5 (October 31, 2023): 5–21. http://dx.doi.org/10.15407/biotech16.05.005.

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The rapid and steady increase in the concentration of CO2, the most abundant greenhouse gas in the atmosphere, leads to extreme weather and climate events. Due to the burning of fossil fuels (oil, coal and natural gas), the concentration of CO2 in the air has been increasing in recent decades by more than 2 ppm per year, and in the last year alone - by 3.29 ppm. To prevent the "worst" scenarios of climate change, immediate and significant reductions in CO2 emissions through carbon management are needed. Aim. Analysis of the current state of research and prospects for the use of carbonic anhydrase in environmental decarbonization programs. Results. Carbonic anhydrase (CA) is an enzyme that accelerates the exchange of CO2 and HCO3 in solution by a factor of 104 to 106. To date, 7 types of CAs have been identified in different organisms. CA is required to provide a rapid supply of CO2 and HCO3 for various metabolic pathways in the body, explaining its multiple independent origins during evolution. Enzymes isolated from bacteria and mammalian tissues have been tested in CO2 sequestration projects using carbonic anhydrase (CA). The most studied is one of the isoforms of human KAz - hCAII - the most active natural enzyme. Its drawbacks have been instability over time, high sensitivity to temperature, low tolerance to contaminants such as sulphur compounds and the impossibility of reuse. Molecular modelling and enzyme immobilisation methods were used to overcome these limitations. Immobilisation was shown to provide greater thermal and storage stability and increased reusability. Conclusions. Capturing carbon dioxide using carbonic anhydrase (CA) is one of the most cost-effective methods to mitigate global warming, the development of which requires significant efforts to improve the stability and thermal stability of CAs.

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Andreas, Roy, Uyi Sulaeman, and Tien Setyaningtyas. "PEMANFAATAN KARBON SABUT KELAPA TERIMPREGNASI UNTUK MENGURANGI TEMBAGA(II) DALAM MEDIUM AIR." Molekul 3, no. 2 (November 1, 2008): 91. http://dx.doi.org/10.20884/1.jm.2008.3.2.53.

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This research is conducted to produce carbons from coconut fibre which approach to activated carbon clause continue with carbon surface modification and the adsorption examination to Cu(II) ions. The research consist of several phase. Carbon making of coconut fibre conducted by carbonization processes at 320-400oC with temperature interval 20oC. Carbon yielded in characterized moisture content, ash content and its adsoprtion to iodium. The carbon surface modification conducted by loaded 2-mercaptobenzotiazol (MBT) on carbon. The adsorpsibility of carbon-MBT tested by influence of contact time, pH, and the isoterm adsorption pattern. The result of the study showed carbonization of coconut fibre which approach the requirement of SII No.0258-89 gained at temperature 320oC. In the present study equilibrium time of 10 minute and pH was found to be optimum for both adsorbent. While type of isothermal adsorption from carban and carbon-MBT adsorbent followed the Langmuir adsorption pattern.

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Kessler, H., W. Bermel, and C. Griesinger. "Determination of carbon-carbon connectivities, assignment of quaternary carbons, and extraction of carbon-carbon coupling constants by carbon-relayed hydrogen-carbon spectroscopy." Journal of Magnetic Resonance (1969) 62, no. 3 (May 1985): 573–79. http://dx.doi.org/10.1016/0022-2364(85)90231-8.

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Hua-Yue, Wu, Ding Jin-Chang, Liu Miao-Chang, and Gao Jing. "Active metallic indium mediated carbon-carbon bond formation in aqueous media : Barbier-type allylation of aldehydes." Journal of Indian Chemical Society Vol. 81, Feb 2004 (February 28, 2004): 160–62. https://doi.org/10.5281/zenodo.5830219.

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Department of Chemistry, Wenzhou Normal College, Wenzhou 325027, P.R. China E-mail: hywu3@ 163.com     Fax: 86-577-88339081 Manuscript received 9 April 2003, accepted 22 August 2003 Mediated by active metallic indium generated in situ from Sm/InCI3.4H2O bimetallic system, aldehydes and allylic bromide undergo efficient Barbier-type allylation reaction to afford homoallylic alcohols in high yields under mild conditions in aqueous media.

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Xu, Xian Feng, Ling Zhi Chai, Hui Li, and Ling Sheng Zeng. "Study on the Electric Properties of Carbon Fibers and its Application for the Preparation of Carbon/Carbon Composites." Materials Science Forum 809-810 (December 2014): 707–10. http://dx.doi.org/10.4028/www.scientific.net/msf.809-810.707.

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Acetylene (C2H2) was used as carbon source gas, nitrogen (N2) as dilution gas. The electric properties of carbon fibers was briefly discussed by energizing the carbon fibers in vacuum condition which were applied for the preparation of carbon/carbon composites by the method of chemical vapor deposition. The deposition mechanism and microstructure of pyrolytic carbons in carbon fibers under different deposition crafts were also discussed. Results indicate that the greater the initial voltage, the higher the temperature, we can change the deposition temperature by changing the initial voltage according to the relationship between the brightness and the surface temperature of carbon fibers. The surface of carbon fibers will be etched in the process of electrifying which would make the pyrolytic carbons preferred deposition on the etching point which became the growth center in the early deposition process. The pyrolytic carbons deposited with a spherical microcrystalline structure under the gas flow of C3H6/N2=2:3, When the rate of gas flow is C3H6/N2=1:2, The pyrolytic carbons deposited with a spherical microcrystalline structure after deposited for 0.5h, but after deposited for 1h, the deposition of large patches of molecular is dominant which lead to that: from a macro perspective, the pyrolytic carbons were a layered structure, From a microscopic perspective, they were a spherical microcrystalline structure with different size.

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Rahmawati, Fitria, Viona Natalia, Agung T. Wijayanta, Siti Rondiyah, Koji Nakabayashi, and Jin Miyawaki. "Carbon Waste Powder Prepared from Carbon Rod Waste of Zinc-Carbon Batteries for Methyl Orange Adsorption." Bulletin of Chemical Reaction Engineering & Catalysis 15, no. 1 (September 3, 2019): 66–73. http://dx.doi.org/10.9767/bcrec.15.1.5148.66-73.

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A research on the preparation of Carbon Waste Powder, CWP, was conducted and made from carbon rod waste which was extracted from used zinc-carbon batteries. This research was an effort to overcome environmental problem caused by battery waste by converting into adsorbent for methyl orange (MO) that frequently used by textile industries. The prepared powder was then analyzed to understand its characteristic peaks, crystallinity, and to compare the properties with other carbonaceous forms, i.e. a commercial Carbon Paper (CP), and a commercial meso- carbon micro-beads (MCMB). The analysis found that CWP is dominated by graphitic carbon. An adsorption experiment was then conducted to study their adsorption ability to methyl orange solution. The result found that those three carbonaceous materials have the ability to adsorb methyl orange with different activities. MCMB has the highest adsorption capacity of 0.197 mg.g-1. Meanwhile, CWP and CP show adsorption capacity of 0.066 mg.g-1 and 0.062 mg.g-1, respectively. Methyl orange adsorption on CWP and CP were under second order, which means the adsorption could be four times faster as the MO solution doubled. Moreover, the rate constant of MO adsorption on CWP is 8×10-4 min-1, which was higher than the rate constant of MO adsorption on CP. It confirmed that the CWP can be used as a promising adsorbent for dye waste water. Copyright © 2020 BCREC Group. All rights reserved

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Zhang, Xiuwei, and Feihai Yu. "Physical disturbance accelerates carbon loss through increasing labile carbon release." Plant, Soil and Environment 66, No. 11 (November 2, 2020): 584–89. http://dx.doi.org/10.17221/257/2020-pse.

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Labile carbon (C) is a major source of C loss because of its high vulnerability to environmental change. Yet its potential role in regulating soil organic carbon (SOC) dynamics remains unclear. In this study, we tested the effect of physical disturbance on SOC decomposition using soils from two abandoned farmlands free of management practice for more than 28 years. The soil respiration rate was measured in undisturbed and disturbed soil columns and was inversely modeled using the two-compartment model. We found that the C loss was 16.8~74.1% higher in disturbed than in undisturbed soil columns. Physical disturbance increased the total amount of labile C (C1) loss by 136~241%, while had no effect on the kinetic decomposition rate constants of both labile (k1) and stable (k2) SOC decomposition. Physical disturbance fragmented the large macroaggregates into small macroaggregates, microaggregates, and free silt and clay-sized fractions. This indicates that C loss was derived from the initially protected labile C, and there was no change of SOC fraction being decomposed. Our results give insights into the understanding of the extent of labile C loss to physical disruption and demonstrate the potential effect of physical disturbance on SOC dynamics.

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Li, Zhong, Hongjuan Wang, Hongxia Xi, Qibin Xia, Jinglei Han, and Lingai Luo. "Estimation of Activation Energy of Desorption of n-Hexanol from Activated Carbons by the TPD Technique." Adsorption Science & Technology 21, no. 2 (March 2003): 125–33. http://dx.doi.org/10.1260/026361703769013862.

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Activated carbon and five kinds of metal-ion-substituted activated carbons, viz. Ag+-activated carbon, Cu2+-activated carbon, Fe3+-activated carbon, Ba2+-activated carbon and Ca2+-activated carbon, were prepared. A model for estimating the activation energy of desorption was established. Temperature-programmed desorption (TPD) experiments were conducted to measure the TPD curves of n-hexanol and hence estimate the activation energy for n-hexanol desorption from the various activated carbons. The results showed that the activation energies for n-hexanol desorption from the Ag+-activated carbon, the Cu2+-activated carbon and the Fe3+-activated carbon were higher than those from the unsubstituted activated carbon, the Ca2+-activated carbon and the Ba2+-activated carbon.

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9

Rivera–Utrilla, J., and M. A. Ferro–García. "Effect of Carbon–Oxygen and Carbon–Nitrogen Surface Complexes on the Adsorption of Cations by Activated Carbons." Adsorption Science & Technology 3, no. 4 (December 1986): 293–302. http://dx.doi.org/10.1177/026361748600300409.

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Adsorption studies of Na+, Cs+, Ag+, Sr2+ and Co2+ from aqueous solutions by surface-treated activated carbons are reported. Carbon–oxygen and carbon–nitrogen surface complexes were formed on an activated carbon from almond shells by treating it with either oxidizing reagents or ammonia. In order to discover the surface acidity and/or basicity of each carbon, selective neutralization techniques were carried out. Both Na+ and Cs+ are adsorbed by only those carbons containing strong acidic functional groups; however, Ag+, Sr2+ and Co2+ are adsorbed not only by these latter carbons but also by those with predominance of basic groups. The results suggest that some of these carbons can be used to remove, separate and pre-concentrate all the cations studied.

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10

Reed, Lawrence A., Juin Tang Huang, Michael McGregor, and Leon Goodman. "Stereospecific carbon-carbon bond formation at secondary carbons in cyclic sugars." Carbohydrate Research 254 (February 1994): 133–40. http://dx.doi.org/10.1016/0008-6215(94)84247-7.

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11

Kim, Young In, and Soo Yong Lee. "A Study on the Erosion of Thermal-Insulation Materials Made of Carbon-Carbon Composites and Graphite." Transactions of the Korean Society of Mechanical Engineers - A 43, no. 5 (May 31, 2019): 307–15. http://dx.doi.org/10.3795/ksme-a.2019.43.5.307.

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12

Diamadopoulos, E., P. Samaras, and G. P. Sakellaropoulos. "The Effect of Activated Carbon Properties on the Adsorption of Toxic Substances." Water Science and Technology 25, no. 1 (January 1, 1992): 153–60. http://dx.doi.org/10.2166/wst.1992.0023.

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The objectives of this work were to relate the activated carbon properties to its adsorptive capacity. The activated carbon needed was produced in the lab from Greek lignite coal. Subsequently, adsorption studies were performed in order to evaluate the efficiency of the various activated carbons to remove toxic substances from water. Two organic substances were used. These were phenol and fulvic acid. Additionally, the adsorption of arsenic (V) was, also, investigated. It was found that the adsorptive capacity of the activated carbons depended primarily on the ash content and the compound. The capacity of the carbon to remove phenol, expressed as mg of phenol removed per g of activated carbon (carbon loading), decreased linearly as the amount of ash in the activated carbon increased. Ash-free activated carbons could adsorb 4 times as much phenol as the activated carbons with a high ash content. On the other hand, fulvic acid and arsenic adsorbed poorly on the ash-free activated carbons. Even for the high surface area activated carbons (over 1000 m2/g), the quantity of fulvic acid or arsenic adsorbed was significantly less than that exhibited by the high ash activated carbons (maximum surface area measured hardly exceeded 300 m2/g). As the amount of ash in the carbon increased, the carbon loading increased as well, up to a certain level, beyond which the amount of ash played no significant role. The beneficial role of ash was explained by the ability of the fulvic acid and arsenic to interact with metal oxides and metal ions, which constitute a significant fraction of the ash.

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13

Kaiser, Katharina, Lorel M. Scriven, Fabian Schulz, Przemyslaw Gawel, Leo Gross, and Harry L. Anderson. "An sp-hybridized molecular carbon allotrope, cyclo[18]carbon." Science 365, no. 6459 (August 15, 2019): 1299–301. http://dx.doi.org/10.1126/science.aay1914.

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Carbon allotropes built from rings of two-coordinate atoms, known as cyclo[n]carbons, have fascinated chemists for many years, but until now they could not be isolated or structurally characterized because of their high reactivity. We generated cyclo[18]carbon (C18) using atom manipulation on bilayer NaCl on Cu(111) at 5 kelvin by eliminating carbon monoxide from a cyclocarbon oxide molecule, C24O6. Characterization of cyclo[18]carbon by high-resolution atomic force microscopy revealed a polyynic structure with defined positions of alternating triple and single bonds. The high reactivity of cyclocarbon and cyclocarbon oxides allows covalent coupling between molecules to be induced by atom manipulation, opening an avenue for the synthesis of other carbon allotropes and carbon-rich materials from the coalescence of cyclocarbon molecules.

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OHMAE, Nobuo. "PL01 RECENT EXPERIMENTAL WORK ON TRIBOLOGY OF CARBON ONIONS AND SOME TOPICS RELATED TO NANO-CARBONS." Abstracts of ATEM : International Conference on Advanced Technology in Experimental Mechanics : Asian Conference on Experimental Mechanics 2011.10 (2011): _PL01–1_. http://dx.doi.org/10.1299/jsmeatem.2011.10._pl01-1_.

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OHMAE, Nobuo. "PLF001 RECENT EXPERIMENTAL WORK ON TRIBOLOGY OF CARBON ONIONS AND SOME TOPICS RELATED TO NANO-CARBONS." Abstracts of ATEM : International Conference on Advanced Technology in Experimental Mechanics : Asian Conference on Experimental Mechanics 2011.10 (2011): _PLF001–1_—_PLF001–12. http://dx.doi.org/10.1299/jsmeatem.2011.10._plf001-1_.

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Nindhia, Tjokorda Gde Tirta, I. Wayan Surata, I. Ketut Adi Atmika, Dewa Ngakan Ketut Putra Negara, and I. Putu Gede Artana. "Processing Carbon Rod from Waste of Zing-Carbon Battery for Biogas Desulfurizer." Journal of Clean Energy Technologies 3, no. 2 (2015): 119–22. http://dx.doi.org/10.7763/jocet.2015.v3.179.

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17

Doğan, E. E., P. Tokcan, and B. K. Kizilduman. "Storage of Hydrogen in Activated Carbons and Carbon Nanotubes." Advances in Materials Science 18, no. 4 (December 1, 2018): 5–16. http://dx.doi.org/10.1515/adms-2017-0045.

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AbstractActivated carbons and carbon nanotube were synthesized with chemical and microwave processes of olive leaf in media with and without ultrasonic waves, and chemical vapor deposition method, respectively. The samples were characterized by x-ray diffraction, calorimetry, Brunauer, Emmett and Teller method, scanning electron microscopy/energy-dispersive X-ray, and zetasizer nano S90 instruments. The activated carbon synthesized in the ultrasonic bath had a higher surface area. The hydrogen adsorption capacity of carbon structures including activated carbons and carbon nanotube was measured as a function of pressure at 77 K. The hydrogen storage capacity of the carbon nanotube is 300% and 265% higher than the hydrogen storage capacity of activated carbons synthesized in medium without and with ultrasonic waves, respectively. Results showed the correlation between hydrogen storage capacity and specific surface area. The highest H2 storage value was obtained with carbon nanotube at 77 K. As a result, activated carbon and carbon nanotube can be used in hydrogen storage and therefore, the olive leaf can be converted into a high added value product in the energy field.

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No, Tae-Kyeong, Dong-Guk Kang, Jae-Sik Seo, Kyung-Mo Yang, and Kwan-Ho Seo. "Effect of Carbon Black on Mechanical and Damping Properties of EPDM/Carbon Black System." Elastomers and Composites 47, no. 3 (September 30, 2012): 231–37. http://dx.doi.org/10.7473/ec.2012.47.3.231.

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Tomaszewski, Damian, and Krzysztof Tadyszak. "Electron Spin Relaxation in Carbon Materials." Materials 15, no. 14 (July 16, 2022): 4964. http://dx.doi.org/10.3390/ma15144964.

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This article focuses on EPR relaxation measurements in various carbon samples, e.g., natural carbons—anthracite, coal, higher anthraxolites, graphite; synthetically obtained carbons—glassy carbons, fullerenes, graphene, graphene oxide, reduced graphene oxide, graphite monocrystals, HOPG, nanoribbons, diamonds. The short introduction presents the basics of resonant electron spin relaxation techniques, briefly describing the obtained parameters. This review presents gathered results showing the processes leading to electron spin relaxation and typical ranges of electron spin relaxation rates for many different carbon types.

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Khandaker, Tasmina, Muhammad Sarwar Hossain, Palash Kumar Dhar, Md Saifur Rahman, Md Ashraf Hossain, and Mohammad Boshir Ahmed. "Efficacies of Carbon-Based Adsorbents for Carbon Dioxide Capture." Processes 8, no. 6 (May 30, 2020): 654. http://dx.doi.org/10.3390/pr8060654.

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Carbon dioxide (CO2), a major greenhouse gas, capture has recently become a crucial technological solution to reduce atmospheric emissions from fossil fuel burning. Thereafter, many efforts have been put forwarded to reduce the burden on climate change by capturing and separating CO2, especially from larger power plants and from the air through the utilization of different technologies (e.g., membrane, absorption, microbial, cryogenic, chemical looping, and so on). Those technologies have often suffered from high operating costs and huge energy consumption. On the right side, physical process, such as adsorption, is a cost-effective process, which has been widely used to adsorb different contaminants, including CO2. Henceforth, this review covered the overall efficacies of CO2 adsorption from air at 196 K to 343 K and different pressures by the carbon-based materials (CBMs). Subsequently, we also addressed the associated challenges and future opportunities for CBMs. According to this review, the efficacies of various CBMs for CO2 adsorption have followed the order of carbon nanomaterials (i.e., graphene, graphene oxides, carbon nanotubes, and their composites) < mesoporous -microporous or hierarchical porous carbons < biochar and activated biochar < activated carbons.

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Kumar, Ponnusamy Senthil, and G. Janet Joshiba. "Carbon Nanotube Composites." Diffusion Foundations 23 (August 2019): 75–81. http://dx.doi.org/10.4028/www.scientific.net/df.23.75.

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The discovery of carbon nanotubes is one of the remarkable achievement in the field of material science and it is a great advancement of Nanotechnology. A carbon nanotube is an expedient material used in several domains and paves way for the welfare of humans in many ways. Carbon nanotubes are nanosized tubes made from graphitic carbons and it is well known for its exclusive physical and chemical properties. The market demand for the nanotubes has increased progressively due to its size dependent, structure and mechanical properties. The carbon nanotubes possess high tensile strength and it is also found to be the durable fibre ever known. It is also found to possess exceptional electrical properties. The carbon nanotube composites have an excellent young’s modulus and higher tensile strength same as graphite carbon. This review plots the properties of carbon nanotubes and portrays the planning and properties of carbon nanotube composites. The wide application of carbon nanotube composites is also explained.

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Hidayat, Sahrul, Sarifah Mudaim, Ali Zulfikar, Nowo Riveli, and Iman Rahayu. "Synthesis of Porous Carbons from Candlenut Shells Using Various Types of Activators for Environmentally Friendly Supercapacitors." Key Engineering Materials 989 (October 28, 2024): 11–21. http://dx.doi.org/10.4028/p-pa5uem.

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Porous carbon is one of the promising electrode materials for supercapacitors due to its unique and engineerable microstructural properties. The study of the synthesis of porous carbon from waste biomass is very important due to the abundance of natural resources, low cost production and contribute to solving environmental problems. In this study, porous carbons derived from candlnut shell with various type of activator was studied the chemical structural, morphological and electrochemical properties then evaluated as electrodes for supercapacitor. We have been successfully synthesized of porous carbon from candlenut shells using three steps of the process, i.e.: carboni-zation, activation and calcination. Carbonization was carried out at 700°C in a furnace using a closed crucible to minimize the oxygen. The chemical activation conducted using three types of activators, i.e. ZnCl2, H3PO4 and KOH then calcination process by heated at 800°C for 1 h under Ar flow. The results of the Fourier-transform infrared (FTIR) analysis show that the carbonization process increases the content of aromatic C=C functional groups and reduce the OH, C-H, C-O and C=O functional groups. The carbonization process has also increased the electrical conductivity of the sample around 0.8525 S/m. The results of Scanning Electron Microscope (SEM) images can be observed that the activation process of carbon has formed which was indicated by the appearance of many pores on the surface area of carbon. N2 adsorption/desorption isotherms (Brunauer–Emmett–Teller (BET)) characterization was indicated that the porous carbon is dominated by mesoporous with a pore size around 2-50 nm. BET characterization also can be determined the surface area of porous carbon around 477 m2/g for ZnCl2, 636 m2/g for H3PO4, and 681 m2/g for KOH. This synthesized materials are further employed in a symmetric supercapacitor using simple glass cell. The best performance of supercapacitor achieved by KOH porous carbons with 16.30 F/g of specific capacitance, 2.26 Wh/kg of energy density and 1038 W/kg of power density.

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Zhang, Su, Lei Qin, Huaihe Song, Xiaohong Chen, Jisheng Zhou, and Zhaokun Ma. "From solid carbon sources to carbon nanotubes: a general water-assisted approach." RSC Adv. 4, no. 97 (2014): 54244–48. http://dx.doi.org/10.1039/c4ra09957e.

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Lodha, Dr Gaurav. "Accounting For Carbon Credits." Indian Journal of Applied Research 1, no. 5 (October 1, 2011): 146–48. http://dx.doi.org/10.15373/2249555x/feb2012/55.

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Gamby, J., P. L. Taberna, P. Simon, J. F. Fauvarque, and M. Chesneau. "Studies and characterisations of various activated carbons used for carbon/carbon supercapacitors." Journal of Power Sources 101, no. 1 (October 2001): 109–16. http://dx.doi.org/10.1016/s0378-7753(01)00707-8.

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El-Nabarawy, Th, G. A. Fagal, and L. B. Khalil. "Removal of Ammonia from Aqueous Solution Using Activated Carbons." Adsorption Science & Technology 13, no. 1 (February 1996): 7–13. http://dx.doi.org/10.1177/026361749601300102.

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The surface areas of non-activated, activated and modified activated carbons were determined from the adsorption of nitrogen at −196°C and of carbon dioxide at 25°C. The base neutralization capacities were determined from the adsorption of NaOH, Na2CO3, NaHCO3 and NH4OH. The amount of oxygen combined to the carbon surface was estimated by measuring the pressure of CO and CO2 obtained on outgassing the carbon sample in the temperature range 300–1000°C. The surface area of activated carbon is not a determining factor in its ammonia adsorption. The surface acidity of the active carbon is a good measure of its capacity for ammonia removal. Ammonia adsorption increases appreciably upon surface oxidation of carbons with oxidizing gases and solutions. The acidic groups on the surface of carbons differ in their strength. Only a fraction of the surface covered by the carbon–oxygen groups is responsible for the capacity of the carbon towards ammonia. Most of the adsorbed ammonia is recovered upon treatment with dilute hydrochloric acid leaving the surface free for successive ammonia adsorption cycles.

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Otani, Sugio. "Nano-carbons formed from carbon monoxide." TANSO 2004, no. 215 (2004): 221–24. http://dx.doi.org/10.7209/tanso.2004.221.

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Jang, Kil-Chan, and Tae-Gyu Kim. "Tribological Characteristics of Si-Diamond-Like Carbon Films in a Condition with Carbon Nanotube Ink Lubricant." Korean Journal of Materials Research 21, no. 3 (March 27, 2011): 149–55. http://dx.doi.org/10.3740/mrsk.2011.21.3.149.

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Liu, J., S. M. Colburn, R. L. Ornberg, and J. R. Ebner. "Studies of surface and structural heterogeneity of carbon supports and carbon-supported catalysts." Proceedings, annual meeting, Electron Microscopy Society of America 53 (August 13, 1995): 418–19. http://dx.doi.org/10.1017/s0424820100138464.

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Activated carbons are generally used as support materials for precious metal catalysts. Properties of carbon that are important to catalyst preparation and application include composition, surface area, microstructure and pore shape and size distribution. Macropores (> 50 nm), mesopores (2-50 nm) and micropores (<2 nm) generally coexist in activated carbons. The accessibility of metal particles dispersed in microporous systems is of predominant importance, especially for large molecules that exhibit slow diffusion transport in narrow pores. It is desirable to have metal particles highly dispersed in readily accessible locations. As part of an on-going program of the characterization of carbonsupported catalysts we report some preliminary observations of the microstructure of carbon supports by a variety of electron microscopy techniquesCommercial carbon supports and carbon-supported Pt catalysts were used in this study. High resolution secondary electron (SE) microscopy, low voltage backscattered electron (LVBE) microscopy and high-angle annular dark-field (HAADF) microscopy techniques were employed to extract surface and structural information.

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Bandosz, T. J. "Importance of Carbon Porosity for Energy-Related Applications." Eurasian Chemico-Technological Journal 21, no. 3 (September 30, 2019): 183. http://dx.doi.org/10.18321/ectj859.

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Nanoporous carbons have many advantages over other adsorbents. This includes their high surface area, pore volume and also conductivity of a carbon matrix. The latter is very important for electrocatalysis. In recent years carbon materials have gained a lot of attention as metal-free catalysts. Their catalytic centers have been linked mainly to nitrogen and sulfur heteroatoms incorporated to the carbon matrix. So far, the research efforts have focused mainly on nanoforms of carbons such a graphene and carbon nanotube (CNT). Inspired by those results, we have performed CO2 and O2 electroreduction on nanoporous carbons assuming that small pores, similar in sizes to target molecules, can enhance the efficiency of these catalytic processes. Indeed, the results suggested that even though the N- and S- based catalytic centers are important, adsorption of O2 or CO2/CO2-/CO/H2 in pores has a positive effect on these overall reduction processes. This minireview summarizes our recent results on the role of porosity in electrocatalysis on porous carbons.

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Liu, Zhouhan, and Shigang Shen. "Evaluation methods, progress and prospect of carbon budget system under dual carbon background." Information 26, no. 1 (March 15, 2023): 35–42. http://dx.doi.org/10.47880/inf2601-03.

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In September 2020, China declared to it to achieve carbon peaks by 2030 and carbon neutralization by 2060. Based on the literature review, this paper analyzes the current status of the carbon revenue and expenditure system. It expouds on the methods and progress of the carbon revenue and expenditure system. On this basis, some suggestions are put forward from four aspects: primary data, accounting methods, and technical means. The current research progress and existing problems were reviewed, and suggestions for future research ideas were put forward, in order to provide a methodology reference for accurate estimation of carbon sinks in terrestrial ecosystems in China, and provide scientific support for the development of carbon neutral emission reduction policies in China.

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Payne, Michael, Molly Klein, Brian Lenhart, Samuel McKinney, Delia Hernandez, and Michele Ostraat. "Graphitic Engineered Carbon Supports for Fuel Cell and Electrolyzer Catalysts: Significance and Characterization Methodology." ECS Meeting Abstracts MA2024-02, no. 11 (November 22, 2024): 1523. https://doi.org/10.1149/ma2024-02111523mtgabs.

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Interconnected mesoporous carbons are an integral support material for many fuel cell and electrolyzer electrode catalysts because of their conductivity, their structural tunability, and the abundance of carbon precursors. The structure and morphology of the carbon support have significant impacts on electrocatalyst performance and durability, and improvements to the synthesis and characterization of carbon supports will ultimately advance sustainable fuel cell and electrolyzer technologies towards widespread adoption. One essential aspect of the carbon structure is its “degree of graphitization,” or the proportion of sp2-hybridized crystalline graphite structures that comprise the solid carbon. Graphitization of solid carbon supports can improve their stability against oxidation and corrosion, ultimately improving the durability and thus catalyst lifetime of fuel cell and electrolyzer devices; as such, it is essential to have detailed methodologies, both quantitative and qualitative, to describe the “degree of graphitization” of carbon supports for performance optimization. Here, we discuss techniques for characterizing the degree of graphitization of solid carbons such as powder X-ray diffractometry (PXRD), Raman spectroscopy, and wide-angle X-ray scattering (WAXS), and apply these techniques to a new class of carbon materials developed by Pajarito Powder known as the Engineered Catalyst Support (ECS). ECS materials are mesoporous carbons with tunable mesopore structures and graphitization levels, allowing these techniques to be demonstrated across a related series of carbon materials. From this analysis, a recommended methodology is given for characterization of graphitic carbon supports in the context of fuel cell and electrolyzer technologies.

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Zamolodchikov, Dmitry. "Carbon Cycle and Climate Change." Journal of Environmental Earth and Еnergy Study (JEEES), no. 2021-02 (July 13, 2021): 53–69. https://doi.org/10.5281/zenodo.5094590.

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The article presents an interview of the deputy editor-in-chief of the journal Environmental, Earth and Energy Study K. Degtyarev with a Doctor of Biological Sciences, Chief Researcher of the Center for Ecology and Forest Productivity of Russian Academy of Sciences Dmitry Zamolodchikov. Topics under discussion: carbon balance in the environment and methods for its assessment, causes of climate change, observation of greenhouse gas emissions, creation of carbon polygons and farms in Russia.

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Liu, Gui Yang, Yan Nan Li, Jun Ming Guo, and Bao Sen Wang. "Porous Carbon Prepared by a Template-Like Method Using Non-Porous Pumice Mineral as Template." Advanced Materials Research 160-162 (November 2010): 1028–31. http://dx.doi.org/10.4028/www.scientific.net/amr.160-162.1028.

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Porous carbons have been prepared by a template-like method using non-porous pumice mineral as a “template”, and sucrose and furfuralcohol as carbon sources. Nitrogen adsorption and scanning electric microscope (SEM) have been used to investigate the pore structure and morphology of the samples. The study results indicate that the surface areas of the carbons prepared from sucrose and furfuralcohol are 208 and 268 m2/g, respectively. The carbon prepared from sucrose is microporous, and the carbon prepared from furfuralcohol is a carbon with both micropores and mesopores.

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Omale, PE, KE Osioyibo, SO Okeniyi, MM Adeyemi, and S. Garba. "Chemical and Thermal Modification of Okaba Coal for Increased Surface and Adsorption Properties." Chemistry Research Journal 2, no. 3 (June 30, 2017): 29–35. https://doi.org/10.5281/zenodo.13954887.

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Activated carbon produced from Okaba coal was modified using potassium hydroxide and phosphoric acid. The effect of this chemical modification was studied using carbon tetrachloride adsorption. Characterization of the activated carbons using scanning electron microscopy and FTIR analysis showed a greater development of porosity obtained by the modified activated carbons and the FTIR spectra displayed bands confirming the presence of hydroxyl, carboxyl and carbonyl functional groups. The predicted influence of chemical modification on activated carbon surface for carbon tetrachloride uptake and adsorption isotherm study from the adsorption models agreed satisfactorily with the experimental values. 

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Liu, Yujia, Edmund Lau, Dario Mager, Marc J. Madou, and Maziar Ghazinejad. "Distinct Roles of Tensile and Compressive Stresses in Graphitizing and Properties of Carbon Nanofibers." Micromachines 12, no. 9 (September 11, 2021): 1096. http://dx.doi.org/10.3390/mi12091096.

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It is generally accepted that inducing molecular alignment in a polymer precursor via mechanical stresses influences its graphitization during pyrolysis. However, our understanding of how variations of the imposed mechanics can influence pyrolytic carbon microstructure and functionality is inadequate. Developing such insight is consequential for different aspects of carbon MEMS manufacturing and applicability, as pyrolytic carbons are the main building blocks of MEMS devices. Herein, we study the outcomes of contrasting routes of stress-induced graphitization by providing a comparative analysis of the effects of compressive stress versus standard tensile treatment of PAN-based carbon precursors. The results of different materials characterizations (including scanning electron microscopy, Raman and X-ray photoelectron spectroscopies, as well as high-resolution transmission electron microscopy) reveal that while subjecting precursor molecules to both types of mechanical stresses will induce graphitization in the resulting pyrolytic carbon, this effect is more pronounced in the case of compressive stress. We also evaluated the mechanical behavior of three carbon types, namely compression-induced (CIPC), tension-induced (TIPC), and untreated pyrolytic carbon (PC) by Dynamic Mechanical Analysis (DMA) of carbon samples in their as-synthesized mat format. Using DMA, the elastic modulus, ultimate tensile strength, and ductility of CIPC and TIPC films are determined and compared with untreated pyrolytic carbon. Both stress-induced carbons exhibit enhanced stiffness and strength properties over untreated carbons. The compression-induced films reveal remarkably larger mechanical enhancement with the elastic modulus 26 times higher and tensile strength 2.85 times higher for CIPC compared to untreated pyrolytic carbon. However, these improvements come at the expense of lowered ductility for compression-treated carbon, while tension-treated carbon does not show any loss of ductility. The results provided by this report point to the ways that the carbon MEMS industry can improve and revise the current standard strategies for manufacturing and implementing carbon-based micro-devices.

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Kwon, Eunkwang, Soohyung Park, and Wontae Lee. "Comparison of Coal-, Coconut-, and Wood-Based Activated Carbons for Removal of Organic Matters in Wastewater Treatment Plant Effluent." Journal of Korean Society of Environmental Engineers 43, no. 4 (April 30, 2021): 257–64. http://dx.doi.org/10.4491/ksee.2021.43.4.257.

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Objectives : This study investigated the removal of dissolved organic materials by coal-, coconut-, and wood-based activated carbons to assess the addition of an activated carbon process to a publicly owned treatment works (POTW).Methods : We assessed the removal of total organic carbon (TOC) by each process in the POTW, and examined the removal of TOC and UVA254 upon adding different amounts of coal-, coconut- and wood-based activated carbons (50, 100, 200, 300, and 400 mg/L) with various contact time (10, 20, 30, 60, 120 min).Results and Discussion : Approximately 80% of TOC was removed throughout the POTW compared to the influent. The activated carbon adsorption tests of coagulated wastewater revealed that the removal rate of TOC and UVA254 from coal-based activated carbon was higher than those of coconut-based and wood-based activated carbons. The removal rate of dissolved organic materials was highest in ozone treated wastewater in all types of activated carbons, followed by ultraviolet disinfected wastewater and coagulated wastewater.Conclusions : It was possible to remove an additional 35-55% of dissolved organic materials upon addition of activated carbon to the treated wastewater although the removal depends on the material of the activated carbon, the injection amount, and the contact time. If an activated carbon process is adopted to the POTW, it can meet the effluent water quality standards (TOC).

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Best, Steven, Jake B. Wasley, Carla de Tomas, Alireza Aghajamali, Irene Suarez-Martinez, and Nigel A. Marks. "Evidence for Glass Behavior in Amorphous Carbon." C — Journal of Carbon Research 6, no. 3 (July 30, 2020): 50. http://dx.doi.org/10.3390/c6030050.

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Amorphous carbons are disordered carbons with densities of circa 1.9–3.1 g/cc and a mixture of sp2 and sp3 hybridization. Using molecular dynamics simulations, we simulate diffusion in amorphous carbons at different densities and temperatures to investigate the transition between amorphous carbon and the liquid state. Arrhenius plots of the self-diffusion coefficient clearly demonstrate that there is a glass transition rather than a melting point. We consider five common carbon potentials (Tersoff, REBO-II, AIREBO, ReaxFF and EDIP) and all exhibit a glass transition. Although the glass-transition temperature (Tg) is not significantly affected by density, the choice of potential can vary Tg by up to 40%. Our results suggest that amorphous carbon should be interpreted as a glass rather than a solid.

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Dobrevski, I., and L. Zvezdova. "Biological Regeneration of Activated Carbon." Water Science and Technology 21, no. 1 (January 1, 1989): 141–43. http://dx.doi.org/10.2166/wst.1989.0017.

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This paper reports the results of investigations into the effect of activated carbon pore structure on the process of carbon regeneration. The suitability of several different commercial activated carbons for biological regeneration was investigated. The pore volume, pore radii, and surface area of the carbons were determined by mercury intrusion and BET methods. The adsorption capacities of the carbons were measured in completely mixed batch reactor systems. Heterogeneous micro-organism cultures and crude cell extract were used for bioregeneration of the carbons. The comparative adsorption and bioregeneration studies showed that there was no correlation between the original adsorption capacity and the regenerated adsorption capacity of activated carbons under the range of conditions used. This is due to the pore structure characteristics of the carbons. It has been found that the regenerated adsorption capacity depends on the volume of the pores with radii, r, of 5 - 50 nm (50 - 500 Å). On the basis of substrate bio-oxidation reactions and the results obtained from identification of some exo-enzymes involved in this bio-oxidation process, the probable mechanism of bioregeneration is discussed.

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Sen, Rahul, R. Sumathy, and C. N. R. Rao. "Diamond-graphite hybrids and the nature of amorphous carbon and diamond-like carbon." Journal of Materials Research 10, no. 10 (October 1995): 2531–35. http://dx.doi.org/10.1557/jmr.1995.2531.

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The nature of amorphous carbon has been explored by molecular mechanics by examining the structures of species such as C84Hx and C150Hx, wherein the percentage of sp3 carbons is progressively increased in a graphitic network. The nature of diamond-like carbon has been similarly investigated by examining the structures of C84Hx and C102Hx where the percentage of sp2 carbons is varied in an sp3 network. The dependence of the average coordination number as well as the sp3/sp2 atom ratio on the atom fraction of hydrogen has been investigated in light of the random covalent network model.

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López-Coca, Ignacio M., Silvia Izquierdo, Guadalupe Silvero, and Carlos J. Durán-Valle. "Sustainable Carbon-Based Materials as Heterogeneous Catalysts in Solvent-Free Acetylation Reactions." Proceedings 9, no. 1 (November 18, 2018): 40. http://dx.doi.org/10.3390/ecsoc-22-05685.

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The catalytic activity of six different carbons was tested in the solvent-free acetylation reaction of alcohols, phenols, and monosaccharides with acetic anhydride. Three commercial carbons—a basic activated carbon M (Merck KGaA), a moderately basic carbon gel X (Xerolutions S.L.), and an activated carbon N (Norit Netherland B.V.)—were studied. From these commercial carbons, three acidic activated carbons—M-S, X-S, and N-S—were obtained by treatment with sulfuric acid. All six carbons were characterized by means of nitrogen adsorption capacity, porosimetry, elemental organic analysis, X-ray photoelectron spectroscopy (XPS), and point of zero charge (PZC) determination. The experiments carried out showed good catalytic activity, the magnitude of which depended on the type of carbon used. The best catalyst was X-S, which combined high acidity with the largest mesoporous volume. Second in line was the commercial carbon M, which was the most basic. The protocol reported herein encompasses several of the characteristics related to the sustainability of chemical processes, such as the innocuous nature and the affordable cost of the catalytic material, the absence of reaction solvent, and the ease of reaction work-up.

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Liu, Lei, Chang-Ce Ke, Tian-Yi Ma, and Yun-Pei Zhu. "When Carbon Meets CO2: Functional Carbon Nanostructures for CO2 Utilization." Journal of Nanoscience and Nanotechnology 19, no. 6 (June 1, 2019): 3148–61. http://dx.doi.org/10.1166/jnn.2019.16590.

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Major fossil fuel consumption associated with CO2 emission and socioeconomic instability has received much concern within the global community regarding the long-term sustainability and security of these commodities. The capture, sequestration, and conversion of CO2 emissions from flue gas are now becoming familiar worldwide. Nanostructured carbonaceous materials with designed functionality have been extensively used in some key CO2 exploitation processes and techniques, because of their excellent electrical conductivity, chemical/mechanical stability, adjustable chemical compositions, and abundant active sites. This review focuses on a variety of carbonaceous materials, like graphene, carbon nanotubes, amorphous porous carbons and carbon hybrid composites, which have been demonstrated promising in CO2 capture/separation and conversion (electrocatalysis and photocatalysis) to produce value-added chemicals and fuels. Along with the discussion and concerning synthesis strategies, characterization and conversion and capture/separation techniques employed, we further elaborate the structure-performance relationships in terms of elucidating active sites, reaction mechanisms and kinetics improvement. Finally, challenges and future perspectives of these carbon-based materials for CO2 applications using well-structured carbons are remarked in detail.

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Richter, Scarlet, Dagmar Haase, Makki Mohsen, and Kolja Thestorf. "Carbon Pools of Berlin, Germany: Organic Carbon in Soils and Aboveground in Trees." Urban Forestry & Urban Greening 54 (July 6, 2020): 126777. https://doi.org/10.1016/j.ufug.2020.126777.

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The emission of climate-relevant gases, especially carbon dioxide, is often associated with urban areas. However, cities have accumulated organic carbon in their soils and vegetation over centuries and offer important ecosystem services for the city through carbon storage. The aim of this study is to estimate the total carbon storage of the central European city of Berlin by combining the organic carbon (Corg) stored in soils and the carbon found in aboveground biomass. We used 432 soil samples that were taken across 18 different land uses in order to estimate the carbon content for each land use based on the laboratory findings of each sample. This large amount of data, which is excellent for such a study, provides an important basis for the evaluation and analysis of the carbon storage potential. Taking into account the degree of soil sealing, the carbon calculations for each individual land use were then transferred to the total area of Berlin in order to produce a spatially explicit carbon map. Soil carbon stocks are reported as units of carbon either as kg/m² or in t/ha for each block. The carbon storage was estimated for both topsoil and subsoil. In addition, we estimated the carbon stored in 596,975 street trees and park trees according to the biomass equations for each tree species. The results show that more than two-thirds of the carbon present is accounted for by soils, which makes them the largest carbon reservoir of the city. Park trees store the most carbon in urban trees apart from urban forest trees. The total carbon stock of Berlin was estimated to be 24,087,344 tons, which corresponds to an approximate quantity of 270 t/ha. The distribution of carbon storage across the city shows the highest values towards the city boundaries. This holds true for the soil as well as the vegetation. The greatest quantities of total carbon are stored in the subsoils of the city’s suburbs. This study is the first of its kind to combine the carbon stocks of the soil and the vegetation in a city in order to estimate its carbon storage potential. It provides detailed soil carbon maps and biomass estimations, which can contribute to carbon storage investigations in other cities with similar climatic and ecological conditions.

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Nkiawete, Mpila Makiesse, and Randy Vander Wal. "Thermo-Catalytic Decomposition Comparisons: Carbon Catalyst Structure, Hydrocarbon Feed and Regeneration." Catalysts 13, no. 10 (October 20, 2023): 1382. http://dx.doi.org/10.3390/catal13101382.

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Thermo-catalytic decomposition (TCD) activity and stability depend upon the initial carbon catalyst structure. However, further transitions in the carbon structure depend on the carbon material (structure and composition) originating from the TCD process. In this article, reaction data are presented that illustrates the time-dependent TCD activity as TCD-formed carbon contributes and then dominates conversion. A variety of initial carbon catalysts are compared, including sugar char, a conductive carbon black (AkzoNobel Ketjenblack), a rubber-grade carbon black (Cabot R250), and its graphitized analogue as formed and partially oxidized. Regeneration of carbon catalysts by partial oxidation is evaluated using nascent carbon black as a model, coupled with subsequent comparative TCD performance relative to the nascent, non-oxidized carbon black. Activation energies for TCD with nascent and oxidized carbons are evaluated by a leading-edge analysis method applied to TCD. Given the correlation between nanostructure and active sites, two additional carbons, engine soots, are evaluated for regeneration and dependence upon nanostructure. Active sites are quantified by oxygen chemisorption, followed by X-ray photoelectron spectroscopy (XPS). The structure of carbon catalysts is assessed pre- and post-TCD by high-resolution transmission electron microscopy (HRTEM). Last, energy dispersive X-ray analysis mapping (EDS) is carried out for its potential to visualize oxygen chemisorption.

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Liu, Yang, Jiareng Chen, Bin Cui, Pengfei Yin, and Chao Zhang. "Design and Preparation of Biomass-Derived Carbon Materials for Supercapacitors: A Review." C 4, no. 4 (September 25, 2018): 53. http://dx.doi.org/10.3390/c4040053.

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The synthesis and application of biomass-derived carbon in energy storage have drawn increasing research attention due to the ease of fabrication, cost-effectiveness, and sustainability of the meso/microporous carbon produced from various biological precursors, including plants, fruits, microorganisms, and animals. Compared to the artificial nanostructured carbons, such as fullerene, carbon nanotube and graphene, the biomass-derived carbons may obtain superior capacitance, rate performance and stability in supercapacitor applications ascribing to their intrinsic nanoporous and hierarchical structures. However, challenges remain in processing techniques to obtain biomass-derived carbons with high carbon yield, high energy density, and controllable graphitic microstructures, which may require a clear understanding over the chemical and elemental compositions, and the intrinsic microstructural characteristics of the biological precursors. Herein we present comprehensive analyses over the impacts of the chemical and elemental compositions of the precursors on the carbon yield of the biomass, as well as the mechanism of chemical activation on the nanoporous structure development of the biomass-derived carbons. The structure–property relationship and functional performance of various biomass-derived carbons for supercapacitor applications are also discussed in detail and compared. Finally, useful insights are also provided for the improvements of biomass-derived carbons in supercapacitor applications.

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46

Khasanova, G., A. Talipbek-kyzy, K. Kasymov, K. Tolokov, and M. Tagaev. "Technology for Producing Composite Nano-structured Material Based on Natural Resources of the KR." Bulletin of Science and Practice 10, no. 2 (February 15, 2024): 369–78. http://dx.doi.org/10.33619/2414-2948/99/35.

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The history of development and current state of the coal sector of Kyrgyzstan is considered. The possibilities of obtaining carbon nanomaterials from carbons, such as carbon nanotubes, nanofibers, sphere particles, graphene, graphene oxide, graphene quantum dots and carbon dots, are analyzed. The optimal moisture content and density of low-dimensional carbon powder were determined. A special mold was used to produce a composite from carbon powders.

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RATNA, CHAKRABORTI (née DASGUPTA), DEB SOUMITRA та RANJAN GHATAK USHA. "Synthesis of α,β-Unsaturated Aldehydes by 1,3-Carbonyl Transposition through One Carbon Homologation. Part 2". Journal of Indian Chemical Society Vol. 62, Nov 1985 (30 листопада 1985): 883–86. https://doi.org/10.5281/zenodo.6325146.

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Department of Organic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Calcutta-700 082 The easily accessible 2-(diethoxymethyl)-6-methoxy-1-tetralone (1) on condensation with methylmagnesium iodide and benzylmagnesium chloride followed by treatment with BF3.Et2O affords 6-methoxy-1-methyl-3,4-dihydro-2-naphthaldehyde (2) and 1-benzyl-6-methoxy-3,4-dihydro-2-naphthaldehyde (3), respectively. The carbinols derived from the reaction of 2-(diethoxymethyl)-1-indanones (4a-4c) with methyllithium undergo smooth transformations to the respective 3-methyl-1H-indene-2-aldehydes (5a-5c). endo-2-(p-Methoxyphenyl)-5-methylbicyclo[3.2.1]octan-6-en-7-aldehyde (14) has been prepared from endo-2-(p-methoxyphenyl)-5-methylbicyclo[3.2.1]octan-6-one (12) through the respective diethoxymethyl derivative (12) by sodium borohydride reduction followed by acid-catalysed rearrangement of the resulting diacetal carbinol.

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48

Nabih, Meryem Hajji, Hamza Boulika, Maryam Elhajam, Noureddine Idrissi Kandri, and Abdelaziz Zerouale. "Synthesis of an Activated Carbon Based on Cardoon Waste and its Comparison to a Commercial Carbon in Terms of Physicochemical Characterization and Organic Dye Adsorption Performance." Key Engineering Materials 954 (August 31, 2023): 41–54. http://dx.doi.org/10.4028/p-wyfpo4.

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The present study aims to evaluate the possibility of using low-cost adsorbents based on Cardoon waste for the depollution of industrial effluents. After characterization of the raw cardoon waste [1], the carbonization was carried out at 350 °C in a muffle furnace. In order to show the performance of the method used to prepare this activated carbon (PC), a comparative study with a commercial carbon (CC) is performed. The obtained activated carbon and the commercial carbon were characterized by thermogravimetric analysis, scanning electron microscopy coupled with EDX, X-ray diffraction, Fourier transform infrared absorption spectroscopy and inductively coupled plasma atomic emission spectroscopy. Approximate analyses of moisture content, volatile matter content, ash content and fixed carbon content, acid-base surface functions, pH at zero charge and iodine value were performed. The obtained results indicate that the main characteristics of the activated carbon prepared at 350 °C are practically similar to those of the commercial carbon; a homogeneous porous surface, an interesting percentage of carbon, a high thermal stability and a disorganized graphitic crystalline structure, the iodine adsorption values on the two carbons are 409.887 mg/g for PC and 430.191 mg/g for CC. The adsorption of methylene blue (MB) on both carbons was performed. The kinetics and isotherms of MB adsorption on the two carbons were evaluated. According to the obtained results, the use of the prepared carbon in effluent treatment can be put into perspective.

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Kim, Hyun-Chul, and Seong Huh. "Porous Carbon-Based Supercapacitors Directly Derived from Metal–Organic Frameworks." Materials 13, no. 18 (September 22, 2020): 4215. http://dx.doi.org/10.3390/ma13184215.

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Numerously different porous carbons have been prepared and used in a wide range of practical applications. Porous carbons are also ideal electrode materials for efficient energy storage devices due to their large surface areas, capacious pore spaces, and superior chemical stability compared to other porous materials. Not only the electrical double-layer capacitance (EDLC)-based charge storage but also the pseudocapacitance driven by various dopants in the carbon matrix plays a significant role in enhancing the electrochemical supercapacitive performance of porous carbons. Since the electrochemical capacitive activities are primarily based on EDLC and further enhanced by pseudocapacitance, high-surface carbons are desirable for these applications. The porosity of carbons plays a crucial role in enhancing the performance as well. We have recently witnessed that metal–organic frameworks (MOFs) could be very effective self-sacrificing templates, or precursors, for new high-surface carbons for supercapacitors, or ultracapacitors. Many MOFs can be self-sacrificing precursors for carbonaceous porous materials in a simple yet effective direct carbonization to produce porous carbons. The constituent metal ions can be either completely removed during the carbonization or transformed into valuable redox-active centers for additional faradaic reactions to enhance the electrochemical performance of carbon electrodes. Some heteroatoms of the bridging ligands and solvate molecules can be easily incorporated into carbon matrices to generate heteroatom-doped carbons with pseudocapacitive behavior and good surface wettability. We categorized these MOF-derived porous carbons into three main types: (i) pure and heteroatom-doped carbons, (ii) metallic nanoparticle-containing carbons, and (iii) carbon-based composites with other carbon-based materials or redox-active metal species. Based on these cases summarized in this review, new MOF-derived porous carbons with much enhanced capacitive performance and stability will be envisioned.

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Islam, M. Nurul, Jahid Sarker, Ayesha Khatton, S. M. Mahruf Hossain, Helena Akhter Sikder, Rashed Ahmed, and A. M. Sarwaruddin Chowdhury. "Synthesis and Characterization of Activated Carbon Prepared from Jute Stick Charcoal for Industrial Uses." Scholars International Journal of Chemistry and Material Sciences 5, no. 3 (March 30, 2022): 33–39. http://dx.doi.org/10.36348/sijcms.2022.v05i03.003.

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Activated Carbons (ACs) were prepared from jute stick charcoal by chemical activation using H2SO4 and H3PO4 ranging temperature from 3000C to 3500. The activated carbons and charcoal prepared from jute sticks were characterized by evaluating the surface chemistry, structural features and surface morphology. The properties of the carbons were characterized by Scanning Electron Microscope (SEM), Brunauer – Emmett-Teller (BET), X-Ray Diffraction (XRD) and the FT-IR method. The jute sticks were converted to activated carbons with the highest surface area (135–245m2/g) and largest mesopores volume (0.14–0.16 cm3/g). The FT-IR spectra exhibited that the pyrolysis of jute stick resulted in the release of aliphatic and O - containing functional groups by thermal effect. However, the release of functional groups is effect of chemical reaction in the ZnCl2, H3PO4, and H2SO4 activation process. A honeycomb carbon structure in activated carbon was formed as observed on SEM images. Although charcoal and activated carbon were prepared at 3000C to 3500, the activated carbon exhibited much lower Raman sensitivity due to the formation of condensed aromatic ring systems. Due to high surface area and high porous structure with abundance of functional groups, the activated carbon prepared from jute sticks charcoal absorbed molecules with much higher than those of other activated carbon.

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Journal articles on the topic 'Carbon'

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