NONAQUEOUS ENZYMATIC SOLUBILIZATION OF COAL-DERIVED MATERIALS

The utilization of enzymes in non-aqueous solvents was explored for th e conversion of coal-derived materials to oil-soluble derivatives for use as fuels. A novel three-step process was developed: (1) an initial low-severity conversion to a form that is soluble or dispersible in a polar solvent; (2) formation of an alcohol substrate with a high acti vity for subsequent enzymatic processing; (3) lipase-catalysed transes terification to a product that is soluble in hydrocarbon solvents. The process was successful for the conversion of a first-stage liquefacti on product from Wyodak subbituminous coal to an acylated product, abou t half of which is soluble in hexane and the remainder in toluene. Coa ls, humic acids and several other higher-molecular-weight coal liquefa ction products, such as Chemcoal, and their derivatives inhibited the lipases, and thus the alcohol intermediates from these precursors were converted in 0-5% yields to acylated products.