METHOD OF EXTENDING BIOMASS CONVERSION CATALYST LIFE

A method of extending the catalyst life of a hydrogenolysis catalyst activity in the presence of biomass and aqueous solution is described. Lignocellulosic biomass solids and aqueous solution is provided to in a hydrothermal digestion unit in the presence of a digestive solvent, and a supported hydrogenolysis catalyst containing (a) sulfur, (b) Mo or W, and (c) Co, Ni or mixture thereof, incorporated into a solid metal oxide support. The lignocellulosic biomass solids in the hydrothermal digestion unit is heated to a temperature in the range of 180° C. to less than 300° C. in the presence of digestive solvent, hydrogen, and in the range of 0.15 wt. % to 12.5 wt. %, based on catalyst, of H2S or H2S source at least partially soluble in aqueous solution, and the supported hydrogenolysis catalyst forming a product solution containing plurality of oxygenated hydrocarbons, the hydrothermal digestion unit maintaining protective sulfur concentration.