Transforming organics via polymerization pathway in advanced oxidation processes: A review
Abstract
This comprehensive review delves into recent advances in oxidative polymerization for treating wastewater, highlighting transformation of organic pollutants into value-added products through advanced oxidation processes. It elucidates the fundamental mechanisms underlying both radical and nonradical pathways, including various oxidizing radicals, singlet oxygen, high-valent metal species, and electron transfer pathway (ETP). The review evaluates the necessary conditions for initiating a novel ETP—direct oxidation transfer pathway, which is pivotal for synthesizing polymeric products. Furthermore, we underscore the importance of understanding the unique behaviors of polymerization in different oxidant systems including hydrogen peroxide, peroxymonosulfate, peroxydisulfate and periodate, to steer the reaction pathway towards highly selective transformations. The discussion also addresses current challenges and future prospects focusing on the limitations of current technologies and the potential for practical applications in producing value-added polymers. This review particularly emphasizes the pertinence of nonradical pathways to transformative removal of organic pollutants and their conversion into valuable polymers, and provides new insights into inspiring designs of heterogeneous systems; with the aim of achieving resourceful carbon recycling and realizing cost-effective chemical inputs thereby contributing to a sustainable and circular economy.