Purification of Lactic Acid Produced by Fermentation: Focus on Non-traditional Distillation Processes

Lactic acid is commonly used in a wide range of fields such as cosmetics, pharmaceutical products, chemistry and food. During the last years, its use for new applications such as production of biodegradable and biocompatible polymers, green solvents and oxygenated chemicals have received considerable attention. However, the relatively high production cost of lactic acid hinders many large-scale applications. In order to cheapen lactic acid production processes, it is necessary to develop more efficient methods of separation and purification. This work reviews some promising non-traditional distillation processes that are currently employed for lactic acid recovery, focusing on reactive distillation and molecular distillation. Advances in such distillation-based processes, their drawbacks and concluding remarks are also presented.