NOVELTY - Making a biomass hydrolysis, comprises (A) catalytically reacting water and a water-soluble (C2+O1+) oxygenated hydrocarbon in a liquid or vapor phase with hydrogen in the presence of a deoxygenating catalyst at a deoxygenating temperature and deoxygenating pressure to produce a biomass processing solvent comprising a (C2+O1-3) hydrocarbon in a reaction stream, and (B) reacting the biomass processing solvent with a biomass component, hydrogen and a deconstruction catalyst at a deconstruction temperature and a deconstruction pressure to produce a biomass hydrolysis.    USE - The method is useful: in aqueous phase reforming and hydrodeoxygenation process; and for making a biomass hydrolysis (claimed) including sugar (including glucose, fructose, sucrose, maltose, lactose, mannose or xylose), sugar alcohols, starch, saccharides and other polyhydric alcohols, arabitol, erythritol, glycerol, isomalt, lactitol, malitol, mannitol, sorbitol, xylitol, arabitol, or glycol, which is useful in the solvent-facilitated catalytic deconstruction of biomass, and for producing fuels, chemicals, and other products.    ADVANTAGE - The method provides biomass hydrolysis in a simple and cost-effective manner.    DETAILED DESCRIPTION - Making a biomass hydrolysis, comprises: either (A) catalytically reacting water and a water-soluble (C2+O1+) oxygenated hydrocarbon in a liquid or vapor phase with hydrogen in the presence of a deoxygenating catalyst at a deoxygenating temperature and deoxygenating pressure to produce a biomass processing solvent comprising a (C2+O1-3) hydrocarbon in a reaction stream, and (B) reacting the biomass processing solvent with a biomass component, hydrogen and a deconstruction catalyst at a deconstruction temperature and a deconstruction pressure to produce a biomass hydrolysis comprising at least one member, which comprises water-soluble lignocelluloses derivative, a water-soluble cellulose derivative, a water-soluble hemicelluloses derivative, a carbohydrate, a starch, a monosaccharide, a disaccharide, a polysaccharide, a sugar, a sugar alcohol, an alditol or a polyol; or (i) catalytically reacting water and a water-soluble (C2+O1+) oxygenated hydrocarbon in a liquid or vapor phase with hydrogen in the presence of a deoxygenating catalyst at a deoxygenating temperature and deoxygenating pressure to produce an oxygenate comprising a (C2+O1-3) hydrocarbon in a reaction stream, (ii) catalytically reacting in the liquid or vapor phase the oxygenate in the presence of a condensation catalyst at a condensation temperature and condensation pressure to produce a biomass processing solvent comprising one or more (C4+) compounds, and (iii) the step (B) as above per se. An INDEPENDENT CLAIM is included for a method of deconstructing biomass, comprising reacting a biomass slurry with a biomass processing solvent comprising a (C2+O13) hydrocarbon at a deconstruction temperature of 80-350 degrees C and a deconstruction pressure of 100-2000 psi to produce a biomass hydro lysate comprising the member, where the biomass processing solvent is produced by catalytically reacting in the liquid or vapor phase an aqueous feedstock solution comprising water and a water-soluble oxygenated hydrocarbons comprising a (C2+O1+) hydrocarbon with hydrogen in the presence of a deoxygenating catalyst at a deoxygenating temperature and deoxygenating pressure.    DESCRIPTION OF DRAWING(S) - The figure shows a flow diagram of a process for catalytically converting biomass to liquid fuels associated with the conversion of biomass hydrolysis.