Method for the production of carbon microspheres 1-20 .mu. in diameter

Abstract

Discrete carbon microspheres having a particle diameter on the order of 1-20 .mu. are obtained by a process involving the steps of homogeneously mixing a pitch having a softening point of 70.degree. - 250.degree. C, a nitrobenzene-insoluble content of not more than 25% and an H/C ratio of 0.2- 1.0 with an aromatic solvent compatible with said pitch and dispersing the resultant mixture in an aqueous solution of a surface active agent with agitation and at a temperature to maintain the viscosity at 200-5000 cps to form microspheres of the pitch/solvent mixture. The dispersion is then cooled to solidify the microspheres. The microspheres 1-20 .mu. in diameter are then separated from the solution and from the finer particles and contacted an organic solvent which is incompatible with the pitch to extract the first-mentioned aromatic solvent from the microspheres. The resultant pitch microspheres are then contacted with an oxidizing agent to render them infusible and baked in an atmosphere of an inert gas to carbonize same.