Structured pattern hollow fiber membrane designed via reverse thermally induced phase separation method for ultrafiltration applications

Membrane fouling is a major problem that hinders the application of the membrane in water filtration. To address this issue, a novel reversed thermally induced phase separation (RTIPS) process is applied to fabricate a patterned polyethersulfone (PES) hollow fiber (HF) membrane using a structured spinneret. Surface patterning could induce turbulence, thereby preventing the accumulation of foulants on membrane surface. The RTIPS method requires lesser material with similar mechanical strength compared to that of conventional TIPS method. The fabrication process is optimized by changing the spinning conditions. A dope composition of 24 wt% PES is chosen to prepare the membrane. The chemical composition of the membrane is confirmed via sophisticated techniques such as Fourier-transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). Scanning electron microscopy (SEM) images of the sample indicates the successful formation of the pattern on the shell side of the HFs. The prepared patterned HF membranes exhibits a high rejection of 97% of bovine serum albumin (BSA), which is comparable to or higher than that of commercial membranes. Moreover, the patterned membrane demonstrates better performance, thereby confirming the effectiveness of this modification in enhancing the antifouling nature.