Fig. 7: Separation strategy for acetoin or 2,3-butanediol.

Acetaldehyde is inserted into an enzymatic cascade where it is converted to 2,3-BDO (R1). Thereby, isopropanol serves as co-substrate and acetone results as co-product. The 2,3-BDO is separated from the reaction solution via distillation (prior extraction is possible) while acetoin is recycled, and the co-substrate and co-product are purged. This flowsheet corresponds to the distillation from aqueous solvent (DIST-AQ) and the distillation from MARS (DIST-ORG).