PROCESS FOR PRODUCING OF CRUDE COAL-TAR PITCH HAVING IMPROVED PROPERTIES AND USE OF SAME

摘要

A process for the production of pitch raw materials having improved properties comprising extracting coal-tar pitch free of solids with a mixture of a supercritical gas extracting agent and an entrainer at elevated temperatures and pressures, passing the extraction mixture to a plurality of separation steps where the supercritical gas and entrainer are removed by lowering the pressure and/or raising the temperature, recycling the mixture of extracting agent and entrainer to the extraction step and recovering the pitch fractions from the separation step, the said pitch fractions being useful for diverse purposes such as soot production, electrode bonding agents, etc.