Active charcoal prepn. from mixt. of (non)carbonaceous particles - by suspension in slurry with lyophobic liquid additive, sepn., drying and heat treatment

摘要

Method of preparing active charcoal comprises the following steps. (A) fine carbonaceous and non-carbonaceous particles are dispersed in a suspending liquid to form a slurry ontg. at least 60 wt.% liquid. (B) A freely flowing liquid having a b.pt. below 80 deg. C which is lyophobic w.r.t. the fine carbonaceous particles is added to the liquid in an amount such that less than 20 wt.% of the freely flowing liquid plus particles actually consists of this second liquid. (C) The mixt. is stirred agglomerate preferentially the fine carbonaceous particles to form small agglomerates while the non-carbonaceous particles remain non-agglomerated in the mixt. (D) The small agglomerates are sepd. from the fine particles. (E) The fine particles are carbonised by heating to at least 400 deg.C. (F) The small agglomerates are activated to form active charcoal. An inexpensive activated charcoal is obtd. by a simplified process, The charcoal has a high content of C, a high specific surface per unit weight and a uniform particle packing, similar to that achieved with spherical particles.