Potential and assessment of lactic acid production and isolation – a review

The majority of commodity plastics is made from petroleum-based chemicals. Lactic acid serves as a monomer for the production of the biodegradable polymer polylactic acid (PLA). This paper provides a review on the state of the art production and isolation process for lactic acid. Problems in production and isolation have been identified, the relevant results in optimized production are presented in the first part of the paper. In the second part, a decision matrix is used as a guideline for the discussion on the state of research in the isolation and purification of lactic acid. Mechanical unit operations, mass transfer unit operations, reactive separation techniques, and process combinations are reported in the literature. At the end, an economic evaluation of isolation processes such as conventional precipitation, reactive membrane separation, and reactive distillation are presented