BioChem - DOS

In-situ carboxylate recovery and simultaneous pH control with tailor-configured bipolar membrane electrodialysis during continuous mixed culture fermentation

Separation and purification technology

Arslan, D.; Zhang, Y.; Steinbusch, K.J.J.; Diels, L.; Hamelers, H.V.M.; Buisman, C.J.N.; De Wever, H.

<P><B>Abstract</B></P> <P>Anaerobic fermentation of organic waste streams by mixed culture generates a mixture of short chain carboxylic acids. To avoid inhibitory effects of the acids or their consumption in internal conversion reactions in the mixed culture environment, <I>in-situ</I> recovery of acids can be beneficial. In this study, electrodialysis with bipolar membranes (EDBM) was applied to a mixed culture fermentation on organic waste streams using a novel EDBM stack with &ldquo;direct contact&rdquo; operation mode. We could demonstrate simultaneous recovery of carboxylates from the fermenter by the EDBM stack while <I>in-situ</I> generation and transport of hydroxyl ions to the fermenter allowed direct pH control. Experiments showed productivity increase after EDBM coupling to the fermenter, and complete elimination of external base consumption. It was also observed that EDBM was able to drive the mixed culture fermentation towards acetate and propionate type of carboxylates.</P> <P><B>Highlights</B></P> <P> <UL> <LI> <I>In-situ</I> recovery of acids by bipolar electrodialysis for mixed culture fermentation. </LI> <LI> Carboxylate productivity increased 1.5 times when ISPR was coupled to fermentation. </LI> <LI> ISPR selectively increased the C2 and C3 acid productivity in continuous reactor. </LI> <LI> Simultaneous acid recovery and pH control in fermenter was achieved by EDBM. </LI> <LI> Base consumption for fermentation was completely eliminated. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

2017

Elsevier

1383-5866

175

pp.27-35

10.1016/j.seppur.2016.11.032

http://click.ndsl.kr/servlet/OpenAPIDetailView?keyValue=05787966&target=NART&cn=NART77093606

Fermentation; ISPR; Bipolar membrane; Electrodialysis; Short chain carboxylates