Abstract: In a coal gasification operation or similar conversion process carried out in the presence of an alkali metal-containing catalyst wherein solid particles containing alkali metal residues are produced, alkali metal constituents are recovered from the particles by treating them with a calcium or magnesium-containing compound in the presence of water at a temperature between about 250.degree. F. and about 700.degree. F. and in the presence of an added base to establish a pH during the treatment step that is higher than would otherwise be possible without the addition of the base. During the treating process the relatively high pH facilitates the conversion of water-insoluble alkali metal compounds in the alkali metal residues into water-soluble alkali metal constituents.

Abstract: A high purity chemical synthesis gas is produced by reacting steam with a carbonaceous feed material in the presence of a carbon-alkali metal catalyst and substantially equilibrium quantities of added hydrogen and carbon monoxide at a temperature between about 1000.degree. F. and about 1500.degree. F.

Abstract: Raw synthesis gas produced by the gasification of coal, heavy oil or similar carbonaceous material is contacted with a reforming catalyst at a temperature in the range between about 1000.degree. and about 1800.degree. F. and at a pressure between about 100 and about 2000 psig prior to adjustment of the carbon monoxide-to-hydrogen ratio and treatment of the gas to increase its B.t.u. content. This catalytic reforming step eliminates C.sub.2 + compounds in the gas which tend to form tarry downstream waste products requiring further treatment, obviates polymerization problems which may otherwise interfere with upgrading of the gas by means of the water gas shift and methanation reactions, and improves overall process thermal efficiency by making possible efficient low level heat recovery.

Abstract: Subdivided carbonaceous feed solids containing volatilizable hydrocarbons are hydrogasified by heating the solids to at least minimum hydrogasification temperature while in dilute phase suspension in a gas containing molecular hydrogen and in contact with subdivided hot solids having a temperature greater than minimum hydrogasification temperature. The feed and hot solids are passed with the hydrogen-containing gas through a transfer line hydrogasification zone having a length which, for the velocity of the solids passage therethrough, limits the residence of the solids therein to the time necessary for devolatilization of the carbonaceous feed solids and for conversion of a predetermined minor proportion of the carbon of the feed solids to methane. Suitably from about one to about 50 mol percent of the carbon in the carbonaceous feed solids is converted to methane.