Progress in down-stream processing of biologically produced 1,3-propanediol

Abstract:

1,3-propanediol is an important raw material in chemical industry. Microbial conversion of glycerol or glucose into 1,3-propanediol has been given much attention due to its renewable resource, mild reaction conditions, and other advantages. It is a challenge to efficiently separate 1,3-propanediol from a mixture of multiple components, such as 1,3-propanediol, 2,3-butanediol, water, residual glycerol, ethanol, macromolecules and salts, for the reason that 1,3-propanediol, glycerol and 2,3-butanediol are all very hydrophilic and have intense polarity. The conventional evaporation and distillation techniques used in the purification of 1,3-propanediol suffer from the problem of high energy consumption and low recovery. It makes the recovery of 1,3-propanediol from a fermentation broth become a bottleneck in industrial production. The down-stream processing of biologically produced 1,3-propanediol mainly includes the removal of protein, salts, water and other impurities. This paper analyze the research progress of these separation technologies and point out the developing direction worth further investigation.