Simulation and optimization of lactic acid salting-out extraction

This work assesses the effects of added ethanol and ammonium sulfate in one-stage salting-out extraction of lactic acid (LA). This process is studied via process simulation using Aspen Plus v8.6 and was optimized regarding LA recovery and water removal. The results of the binodal curve and LA extraction presented a good agreement with experimental data. The experimental designs performed in Statistica v7.0 showed that the amount of ethanol was the most significant factor for LA recovery and water removal, and sulfate for precipitate formation. In the optimization, the biggest challenge was that the factors that led to maximum LA recovery were opposite to the ones of maximum water removal. Nevertheless, an optimized scenario was achieved: 80% LA recovery, 47% water removal, and 7% solvent loss.