US 4,728,418 A · Process for the low-temperature depolymerization of coal and its conversion to a hydrocarbon oil

Abstract

A novel process for the low-temperature depolymerization and liquefaction of coal wherein the coal is subjected to sequential processing steps for the cleavage of different types of intercluster lnikages during each processing step. A metal chloride catalyst is intercalated in finely crushed coal and the coal is partially depolymerized under mild hydrotreating conditions during the first processing step. In the second processing step the product from the first step is subjected to base-catalyzed depolymerization with an alcoholic solution of an alkali hydroxide, yielding an almost fully depolymerized coal, which is then hydroprocessed with a sulfided cobalt molybdenum catalyst in a third processing step to obtain a hydrocarbon oil as the final product.

Claims20

Dependent claims

A process for the low temperature depolymerization and liquefaction of fine particles of coal comprising the combined, sequential steps of:

intercalating the fine particles of coal with a catalytic amount of a metal chloride catalyst;
a first mild hydrotreating of the intercalated coal to produce a partially depolymerized coal as a first intermediate product mix, said product mix comprising depolymerizated coal particles containing catalyst and an organic liquid;
separating substantially said coal particles from said organic liquid;
removing substantially said catalyst from said coal particles;
recombining said substantially catalyst depleted coal particles and organic liquid;
reacting said first intermediate product with a base-catalyzed depolymerization agent consisting essentially of an alcoholic solution of an alkali metal hydroxide to produce depolymerized coal as a second intermediate product;
and
hydroprocessing the second intermediate product with a sulfided cobalt molybdenum catalyst to produce a hydrocarbon oil as a final product.

5 more elements

A process for the depolymerizing and liquefaction of coal to produce a high quality hydrocarbon oil comprising the combined, sequential steps of:

cleaving methylene, benzyletheric and a small portion of the aryletheric linkages in the coal framework by mild hydrotreatment in the presence of a catalyst capable of cleaving said methylene, benzyletheric and aryletheric linkages to obtain a partially depolymerized coal as a first intermediate product;
removing substantially the catalyst present in said first intermediate product;
further depolymerization of the first catalyst depleted intermediate product by hydrolysis or alcoholysis of the diaryletheric bridging groups, and at least a portion of the dibenzofuranic and other bridging groups to obtain a more fully depolymerized coal as a second intermediate product;
and
hydroprocessing the second intermediate product under conditions suitable to achieve substantial heteroatom removal and for partial ring hydrogenation and attendant C--C hydrogenolysis thereby producing a high quality hydrocarbon oil as final product from the coal.

2 more elements

Dependencies are inferred from the claim text.

Process for the low-temperature depolymerization of coal and its conversion to a hydrocarbon oil

Life of this patent

Process for the low-temperature depolymerization of coal and its conversion to a hydrocarbon oil

Life of this patent

Abstract

Claims20