Process for coal liquefaction employing a superior coal liquefaction process solvent

A process for coal liquefaction employing a superior coal liquefaction solvent comprising:

• admixing a first portion of particulate coal with a distillable aromatic hydrocarbon solvent having a boiling temperature in the range of from about 300.degree. F. to about 950.degree. F. to form a slurry;
• heating the slurry to a temperature level in the range of from about 700.degree. F. to about 800.degree. F. in the presence of hydrogen gas while maintaining the slurry at a pressure in the range of from about 1000 psig. to about 2500 psig. to effect a conversion of the coal in the slurry to coal liquefaction products comprising distillable and substantially nondistillable soluble coal products and insoluble coal products in admixture with the distillable aromatic hydrocarbon solvent;
• distilling said coal liquefaction products to separate said distillable aromatic hydrocarbon solvent and distillable soluble coal products from the remainder;
• admixing the remainder with a deashing solvent to form a prepared mixture;
• separating said prepared mixture into a first light phase and a first heavy phase comprising insoluble coal products and some deashing solvent by maintaining the prepared mixture at a first temperature level in the range of from about 400.degree. F. to 700.degree. F. and a pressure in the range of from about 600 psig. to about 1500 psig.;
• heating said first light phase to a second temperature level higher than the first temperature level while maintaining the pressure in the range of from about 600 psig. to about 1500 psig. to effect a separation of said first light phase into a second light phase comprising light solvent refined coal and deashing solvent and a second heavy phase comprising heavy solvent refined coal and some deashing solvent;
• recovering the light solvent refined coal from the second light phase;
• admixing a portion of the light solvent refined coal with the distillable aromatic hydrocarbon solvent recovered from admixture with the coal liquefaction products to form a coal liquefaction solvent, said light solvent refined coal comprising at least 15 percent by weight of said coal liquefaction solvent;
• and
• contacting said coal liquefaction solvent with a second portion of particulate coal at a temperature in excess of about 800.degree. F. and a pressure in excess of about 1000 psig. to effect a conversion of said particulate coal to coal liquefaction products comprising distillable and substantially nondistillable soluble coal products and insoluble coal products in admixture with said coal liquefaction solvent.