Separation of insoluble material from coal liquefaction product by use of a diluent

Claim 1

A process for separating insoluble material from a coal liquefaction product produced from a coal feed and comprised of insoluble material and carbonaceous matter dissolved in a coal liquefaction solvent, said coal liquefaction product having quinoline insolubles of at least 15 wt. %, comprising: diluting said coal liquefaction product with a liquid diluent, said liquid diluent being a solvent for the quinoline soluble and benzene insoluble components in said coal liquefaction product and a nonsolvent for quinoline insoluble components and being added in an amount to provide a mixture of coal liquefaction product and diluent having quinoline insolubles of no greater than 13 wt.%; mixing the diluted coal liquefaction product with a liquid promoter, said liquid promoter being different from said diluent and having a 5 volume percent distillation temperature of at least about 250° F. and a 95 volume percent distillation temperature of at least about 350° F. and no greater than about 750° F., said promoter liquid having a characterization factor (K) of at least 9.75, said liquid promoter having a characterization factor greater than said coal liquefaction solvent; and separating insoluble material from said diluted coal liquefaction product mixed with liquid promoter by gravity settling to thereby recover a liquid overflow essentially free of insoluble material and a liquid underflow containing the insoluble material.