Biomass converting processes often struggle with downstream processing of dilute multicomponent mixtures. Liquid-liquid extraction is perfectly suited for removing carboxylic acids from aqueous streams, but solvent recovery is still energy intensive. Solvent recovery is simplified by reactive distillation, whereas the carboxylic acids are directly converted into their corresponding methyl esters. A process concept on the basis of formic acid and acetic acid isolation was evaluated and discussed for uncatalyzed and catalyzed batch reactive distillation with the acid laden solvent Cyanex (R) 923. 4-Dodecylbenzenesulfonic acid was used as catalyst. Catalytic conversion yielded 100% methyl formate and 88% methyl acetate formation.