Photo-Based Advanced Oxidation Processes for Zero Pollution: Where Are We Now?
Dawei Wang, Allyson L. Junker, Mika Sillanpää, Yilan Jiang, Zongsu Wei
Abstract
The ambitious “zero pollution” goal entails the upgrade of conventional (waste)water treatment processes. Among various options, photo-based advanced oxidation processes (photo-AOPs) have shown promising capabilities in terms of eliminating contaminants of emerging concern. While photo-AOP applications exist worldwide, some key issues remain that hamper their wider practice and achieving the potential zero pollution goal. In this perspective, we briefly summarize the state of photo-AOPs, including photo-hydrogen peroxide (H2O2), -Fenton, -persulfate (S2O82- ), -ozone (O3 ), and -catalysis systems. We also discuss the major theoretical and technical knowledge gaps of photo-AOPs, which require further research to advance these treatments and to progress towards zero-toxic discharge for safe water reuse.