The Department of Environmental Science and Engineering of our university has made new progress in the treatment technology of heterogeneous chemical oxidation water. Professor Yu Hanqing's research group, in collaboration with Professor Menachem Elimelech and others from Yale University in the United States, revealed a dominant direct oxidation transfer process (DOTP) in heterogeneous catalytic persulfate oxidation systems, and developed this process into a new water treatment technology. The results of the relevant study were "Simultaneous nanocatalytic surface activation of pollutants and oxidants for highly efficient water. "decontamination" was recently accepted for publication by Nature Communications (DOI: 1038/s41467-022-30560-9).

Heterogeneous catalytic persulfate oxidation has developed rapidly in recent years as a new chemical oxidation technology. Previous studies have shown that the removal process of organic pollutants in this technology system is mainly advanced oxidation process (AOP). Through literature research, Yingjie Zhang, a doctoral student, and Guixiang Huang, a postdoctoral fellow, found that there is a common phenomenon of electron equivalent non-conservation in these systems, that is, the total amount of electrons given by the mineralization of pollutants is much larger than the amount acceptable by the oxidant. Based on this paradox, they systematically and deeply study these systems, and reveal from the source that a direct oxidation transfer process (DOTP) is actually dominant in these systems, which is different from AOP in nature. In DOTP, direct 2-electron REDOX reaction occurs between pollutants and oxidants on the heterogeneous catalyst surface, and the resulting pollutant intermediates are stabilized by the catalyst surface and spontaneously undergo surface polymerization reaction or surface coupling reaction, and the formed products are enriched on the catalyst surface, thus achieving effective removal of pollutants in water. This study elucidates the three functions of activation, stabilization and enrichment of the heterogeneous catalyst surface during the reaction process, reveals the advantages of DOTP, such as small oxidant consumption, large pollutant enrichment capacity, and no toxic by-products, and demonstrates the feasibility of DOTP as a new water pollution control technology for practical wastewater treatment.

The co-first authors of the paper are Yingjie Zhang, a PhD student, and Guixiang Huang, a postdoctoral fellow at the Key Laboratory of Urban Pollutant Transformation, CAS. This work was supported by the National Natural Science Foundation of China and the Key Research and Development Program of the Ministry of Science and Technology.

DOTP示意图

论文链接：https://www.nature.com/articles/s41467-022-30560-9

(Department of Environmental Science and Engineering, Department of Scientific Research)
Source: HKUST News Network