Photocatalytic Membrane Reactor Utilizing Immobile Photocatalytic Active Layer on Membranes for the Removal of Micropollutants

Treatment of micropollutant-contaminated water using photocatalytic membrane reactors (PMRs) faces certain operational challenges including catalyst agglomeration and loss of reactor efficiency over time. Designing a PMR with a photocatalytic active layer on the membrane surface could be an alternative strategy to improve the reactor efficiency. Therefore, this study determined the optimum PMR design using commercially available membranes with two different catalysts (ZrO2 and TiO2) in the presence or absence of ultraviolet (UV) light at both high and low fluences for efficient photodegradation of para-chlorobenzoic acid (pCBA) and 15 different organic micropollutants. Comparing the UV types, vacuum UV (VUV) showed 24-36% higher micro-pollutant degradation than low-pressure UV (LUV). Micro-pollutant degradation was 20-36% higher in the presence of the membrane than in its absence and similar at both fluences for both UV types. VUV had 28-35 and 14-21% higher pCBA degradation than LUV at high and low fluences, respectively. The high fluence showed 3.6-6.7 and 12.5-24.5% higher pCBA degradation capacity than the low fluence for LUV and VUV, respectively. Comparing the catalyst types, there was a negligible difference in the degradation efficiency between TiO2 and ZrO2. The results indicate a promising pathway for developing a pilot-scale VUV-equipped PMR for treating micropollutant-contaminated water.