Developing Thin film composite nanofiltration membrane for lactic acid Production in membrane bioreactor

In this work thin film composite nanofiltration membrane was fabricated for lactic acid production in membranebioreactor. The SEM and AFM studies indicated that a rough and dense film was formed on the polyethersulfone (PES)support membrane. The permeate flux and separation properties of the membrane was investigated at 25 °C and transmembrane pressure (TMP) of 5 bar and was compared with 3 commercial NF membranes. The high lactose and lowlactic acid rejection of 80% and 19% was obtained with thin film composite membrane. The membrane was used to lacticacid production from lactose of whey in membrane bioreactor (MBR). The maximal productivity of 6.1 gL-1h-1 wasobtained at the dilution rate of 0.24 h−1, while the value obtained in the CBR was 3.4 gL-1h-1 at the same dilution rate.The maximum concentration of lactic acid was obtained at the dilution rate of 0.04 h−1 in both MBR and CBR with valuesof 38.2 and 22.5 gL-1. The inhibiting effect of lactic acid was not observed in MBR system.

کلیدواژه ها:

Thin film composite membrane ، Nanofiltration ، Lactic acid ، Membrane bioreactor