Pervaporation performance of PDMS/ceramic composite membrane in acetone butanol ethanol (ABE) fermentation–PV coupled process

Pervaporation (PV) has attracted increasing attention owing to its potential application in biofuel recovery from biomass fermentation process. In this work, PDMS/ceramic composite membrane was directly coupled with acetone butanol ethanol (ABE) fermentation to in situ remove ABE solvents from the fermentation broth. The membrane PV performances and stability in the spent fermentation broth and fermentation–PV coupled process were systematically investigated. As observed in the ABE fermentation broth, the inorganic salts favored increasing the membrane selectivity whereas the microbial cells resulted in a reduced PV performance. Although a fluctuation of membrane performance was observed due to the occurrence of membrane fouling in the fermentation–PV coupled process, the PDMS/ceramic composite membrane exhibited a high flux of 0.670 kg/m2 h and applicable ABE separation factor of 16.7. The SEM, AFM and FT-IR characterizations confirmed that the membrane fouling originated from the adsorption of active cells on the membrane surface. Nevertheless, the membrane fouling in the coupled process was reversible, with easy recovery of PV performance after a simple water rinse.

► Pervaporation was directly coupled with ABE fermentation using PDMS/ceramic composite membrane.
► Inorganic salts in the ABE fermentation broth increased membrane selectivity while microbial cells reduced PV performance.
► PDMS/ceramic composite membrane exhibited a high flux and applicable separation factor during the fermentation–PV coupled process.
► Membrane fouling originated from the adsorption of active cells on the membrane surface and could be easily removed by a simple water rinse and membrane PV performance was restored.