Obtaining of high porous carbon material using thermochemical conversion of wood biomass under pressure

A method is presented for obtaining activated carbons (highly porous carbon materials) based on plant (wood) raw materials using a developed and manufactured experimental setup, consisting of a steam generator, a superheater, a pyrolysis and activation chamber and a cooler with a heat exchanger with forced convection. The analysis of the features of chemical and physical activation of charcoal, obtained by pyrolysis of wood raw materials, is carried out, and a conclusion is made about the advantage of physical activation, based on the use of water vapor as an activating agent. A description of the results of experimental studies carried out using the developed installation is given. These results confirm the conclusions of other studies that excessive pressure increases the mass yield of solid products formed during the thermochemical conversion of plant biomass. It was found that an increase in pressure, at which pyrolysis occurs, leads to an increase in the carbon content in charcoal. So, with an increase in pressure at which pyrolysis was carried out, from 1 to 8 atm, the carbon content in charcoal increased from 88.3 to 93.7 wt.%. Data on the efficiency of physical activation of solid products of pyrolysis of woody biomass using water vapor are presented and a conclusion is made that this direction is promising in the development of the foundations for the production of highly porous carbon materials.

1. Vasil’ev S. N., Gamova I. A., Vekki A. V. de, Deineko I. P., Itsko E. F., Kalinskaya T. V., Podkletnova N. M.,. Pokonova Yu. V, Rybakov V. A., Saratov I. E., Filatov B. N., Fomenko V. N., Yudkevich Yu. D. New Handbook of Chemistand Technologist. Raw Materials and Products of the Industry of Organic and Inorganic Substances. Part 2. St. Petersburg, ANO NPO Professional Publ., 2005. 1144 p. (in Russian).

2. Association of Independent Experts in the Field of Mineral Resources, Metallurgy and Chemical Industry. Market Overview of Activated (Active) Carbon in the CIS. Moscow, 2019. 193 p. (in Russian).

3. Hagemann N., Spokas K., Schmidt H. P., Kägi R., Böhler M. A., Bucheli T. D. Activated Carbon, Biochar and Charcoal: Linkages and Synergies across Pyrogenic Carbon’s ABCs. Water, 2018, vol. 10, iss. 2, p. 182. https://doi.org/10.3390/w10020182

4. Spink G., Kondoroshi A., Houkas P., eds. Molecular Biology of Bacteria Interacting with Plants. St. Petersburg, “IPK “BIONT” Publ., 2002. 567 p. (in Russian).

5. Smišek M., Cerný S. Active Carbon, Manufacture, Properties and Applications. Amsterdam ; London ; New York: Elsevier Publ. Co., 1970. VII, 479 p. https://doi.org/10.1002/ange.19710830820

6. Marsh H., Reinoso F. R. Activated Carbon. Amsterdam, Elsevier, 2006. 554 p. https://doi.org/10.1016/B978-0-08-044463-5.X5013-4

7. Daud W. M. A. W., Houshamnd A. H. Textural characteristics, surface chemistry and oxidation of activated carbon. Journal of Natural Gas Chemistry, 2010, vol. 19, iss. 3, pp. 267-279. https://doi.org/10.1016/S1003-9953(09)60066-9

8. Molina-Sabio M., Gonzalez M., Rodriguez-Reinoso F., Sepúlveda-Escribano A. Effect of steam and carbon dioxide activation in the micropore size distribution of activated carbon. Carbon, 1996, vol. 34, no. 4, pp. 505-509. https://doi.org/10.1016/0008-6223(96)00006-1

9. Suliman W., Harsh J. B., Abu-Lail N. I., Fortuna A.-M., Dallmeyer I., Garcia-Pérez M. The role of biochar porosity and surface functionality in augmenting hydrologic properties of a sandy soil. Science of the Total Environment, 2017, vol. 574, pp. 139-147. https://doi.org/10.1016/j.scitotenv.2016.09.025

10. Xiao F., Pignatello J. J. Effects of post-pyrolysis air oxidation of biomass chars on adsorption of neutral and ionizable compounds. Environmental Science & Technology, 2016, vol. 50, iss. 12, pp. 6276-6283. https://doi.org/10.1021/acs.est.6b00362

11. Campo B. G. del. Production of activated carbon from fast pyrolysis biochar and the detoxification of pyrolytic sugars for ethanol fermentation. 2015. Graduate Theses and Dissertations. 14691. Available at: https://lib.dr.iastate.edu/etd/14691 (accessed 12 December 2019).

12. Vasilevich S. V., Malko M. V., Bogach. N., Degterov D. V., Asadchiy A.N. Study of the process of obtaining charcoal by pyrolysis under pressure. Vestsi Natsyyanal’nai akademii navuk Belarusi. Seryya fizika-technichnych navuk = Proceedings of the National Academy of Sciences of Belarus. Physical-technical series, 2017, no. 3, pp. 64-71 (in Russian).

13. Vasilevich S. B., Malko M. V., Degterov D. V., Asadchiy A. N. Computational study of the yield of solid products of wood pyrolysis at elevated pressure. Energetika. Izvestiya vysshikh uchebnykh zavedenii i energeticheskikh ob"edinenii SNG = ENERGETIKA. Proceedings of CIS higher education institutions and power engineering associations, 2020, vol. 63, no. 3, pp. 253-263 (in Russian). https://doi.org/10.21122/1029-7448-2020-63-3-253-263