Abstract: Levulinic acid and formic acid are valuable chemical intermediaries present in byproducts of some biomass conversion processes. Described herein are commercially viable processes for extracting levulinic acid and formic acid at high recovery. Under the present approach, levulinic acid and formic acid may be extracted from an aqueous reactor product, such as an acidic brine (e.g., calcium chloride brine) feed from a biomass hydrolysis reaction. If present, mineral acid catalysts may be recovered. Embodiments use solvents such as, e.g., 2-methyl tetrahydrofuran, for extracting levulinic acid and formic acid from the aqueous solution.