Phosphorus-doped g-C3N4 integrated photocatalytic membrane reactor for wastewater treatment

• DOI: 10.1016/j.memsci.2019.03.012
• Publication Date: 2019-03-08T02:24:57Z
• Authors: Chechia Hu; Mao-Sheng Wang; Chien-Hua Chen; Yi-Rui Chen; Ping-Hsuan Huang; Kuo-Lun Tung
• Keywords: 11. Sustainability; 01 natural sciences; 6. Clean water; 0104 chemical sciences; 12. Responsible consumption

Abstract Photocatalytic membrane reactors (PMRs) have been widely used in wastewater treatment over the past few years. In this study, P-doped g-C3N4 (PCN), a metal-free, visible light (Vis)-driven photocatalyst, was prepared and coated on an Al2O3 substrate followed by integration with an inorganic Al2O3 hollow fiber membrane module for use as a PMR. The 10 wt % of PCN exhibited the highest degradation activity for methyl blue (MB) removal under Vis irradiation because the C sites and vacancies within the heptazine rings of the CN units were substituted with P to improve charge separation and reduce the number of unpaired electrons. The PMR exhibits higher efficiency and stability in the removal of MB, methyl orange, phenol solution, and a mixture of the three organic compounds than do individual hollow fiber membranes or photocatalysis systems. The TOC (total organic carbon) analysis revealed that more than 92% of the phenol was decomposed and mineralized in the PMR, which also had a MB removal efficiency of greater than 90% when repeatedly used for four times. These results indicate that the PMR developed in this study is highly active and stable, and can serve as a promising system for effective removal of organic pollutants in wastewater.