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.

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