Fabrication and characterization of different braid-reinforced PVC hollow fiber membranes to use in membrane bioreactor for wastewater treatment

In this research, polyvinyl chloride (PVC) polymer was applied for the first time in the fabrication of braid-reinforced hollow fiber membranes for ultrafiltration applications. Different concentrations of PVC solutions were cast on tubular braids and coagulated by the phase inversion method in a pure water bath to produce membranes with various porosities and pore sizes. The characterizations such as scanning electron microscopy, overall porosity, contact angle and mean pore size were done to understand membrane morphology. The antifouling property of membranes was explained using bovine serum albumin (BSA). The contact angles of membranes were increased from 64.9° ± 2.2 to 72.8° ± 2.1, while the overall porosity decreased from 43.8 ± 1.2% and 19.6 ± 3.3% for 11 wt% and 17 wt% PVC membranes, respectively. Permeate flow decreased due to decreased pore size of membranes as a result of increased PVC content. Besides, the flux recovery ratio, reversible and irreversible fouling studies showed that better antifouling characteristics observed with increasing of PVC content. A high removal efficiency of 87.2% for BSA was also demonstrated by the optimal membrane (15 wt% PVC), along with an increased flux recovery ratio of 96.6%. After investigating the rejection of COD in a membrane bioreactor setup, all membranes revealed that they were higher than 98%.