Construction of high-performance Ce-doped TiO2 tight UF membranes for protein separation

Abstract

The membrane structure and properties have a significant influence on its anti-fouling performance during the separation process. In this study, Ce was introduced to inhibit the phase transformation of TiO2 to obtain a tight ultrafiltration (UF) membrane with a more uniform pore size, a more integrated membrane layer as well as to strengthen the membrane surface charge to provide superior anti-fouling performance for the membrane during protein separation. Single anatase phase of the material proves that the introduction of Ce effectively inhibited the phase transformation of TiO2 and prevented the occurrence of cracks. The prepared Ce-doped TiO2 membrane exhibited excellent performance, with a membrane thickness of 700 nm, water permeance of 175 L·m−2·h−1·bar−1 and molecular weight cut-off of approximately 18 kDa. Additionally, it showed excellent BSA separation performance, as the stable permeance and rejection rate could be maintained at 120 L·m−2·h−1·bar−1 and 100 %, respectively. Meanwhile, Ce-doped TiO2 membrane showed superior anti-fouling performance compared to pure TiO2 membrane due to its strengthened surface charge and uniform pore size, with the J/J0 maintained a value of 0.69. Based on the obtained results, the Ce-doped TiO2 membranes prepared in this study exhibit good potential for protein separation.