Activated Carbon Produced from Charcoal Obtained by Vacuum Pyrolysis of Softwood Bark Residues

Abstract

Vacuum pyrolysis of softwood bark residues yields besides oil, charcoal as second valuable product. The activation behavior of the vacuum pyrolysis charcoal was compared to charcoal produced during conventional, atmospheric carbonization process. Steam activation of charcoal obtained by vacuum pyrolysis yields an activated carbon with a higher surface area than by using charcoal produced during atmospheric carbonization process. This can be related to the more open pore structure of the vacuum pyrolysis charcoal. Steam activation of the vacuum pyrolysis charcoal was studied at temperatures ranging from 760 to 850 °C. Activated carbons with surface areas above 1200 m 2 /g and micropore volumes above 0.40 cm 2 /g were obtained.Depending on the activation conditions, carbons with properties (surface area, pore volume, pore structure and methylene blue value) similar to commercial grades were produced.

Production of Activated Carbon within the Dual Fluidized Bed Gasification Process

“…This is far lower than the extents of char conversion (>55%) reported for the production of AC through physical activation with steam (BET surface areas > 800 m 2 / g). 53,54 Although the extent of char conversion in other DFB gasifiers might be >5%, the significantly lower fuel particle retention times in those gasifiers, as compared to those applied in the production of commercial AC, suggest that the extents of char conversion in those gasifiers could be lower than what is achieved during the production of commercial AC. Therefore, the BET surface area of the unconverted char that is circulated from the gasification chamber to the combustion chamber of a DFB gasifier will likely be lower than that of commercially produced AC.…”

Sorption of arsenic, cadmium, and lead by chars produced from fast pyrolysis of wood and bark during bio-oil production

“…Bio-char is a pyrolytic by-product during bio-oil production [38][39][40][41][42][43][44][45][46][47][48][49][50][51]. This oxygen-rich char is different from that formed by partial combustion.…”

Effects of vacuum pyrolysis conditions on the characteristics of activated carbons derived from pistachio-nut shells

“…The results showed that vacuum pyrolysis derived char had a higher reactivity than atmospheric pyrolysis char due to a higher oxygen content of the vacuum pyrolysis char. Steam activation of charcoals obtained by vacuum and atmospheric pyrolysis of softwood bark residues was investigated by Cao et al [9,10]. Steam-activated carbons from charcoals, which were prepared by vacuum pyrolysis, yielded a higher surface area than those from charcoals produced from atmospheric carbonization.…”