A method to produce biofuels from biomass is provide by contacting the biomass with an aqueous media to form an extracted biomass, separating at least a portion of an aqueous liquor from the extracted biomass thereby providing the aqueous liquor stream comprising soluble carbohydrates; contacting the aqueous liquor stream with a purification substrate effective to remove sulfur compounds and nitrogen compounds thereby producing a treated carbohydrate stream having less than 35% of the sulfur content and less than 35% of the nitrogen content of the untreated aqueous liquor feed, based on the untreated aqueous liquor stream, then contacting the treated carbohydrate stream with an aqueous phase reforming catalyst to form a plurality of oxygenated intermediates; and processing at least a portion of the oxygenated intermediates to form a liquid fuel.