Yifei Wang, Yiwei He, Sihui Yang, Jiayi Yuan, Guojing Wang, Xiaoyu Zhang, Pengfei Cheng, Artem Yurevich Manyakhin, Xiaolin Xu, Jianhua Fan, Yanyan Dang, Xiongfang An
Green Carbon 2026
The treatment of organophosphorus pesticide (OP) wastewater and the recovery of inorganic phosphate (IP) resources are constrained by traditional technological bottlenecks. The core challenge lies in achieving both efficient degradation of OPs and simultaneous recovery of IPs within a single system. In this study, a bifunctional MgO(200)@g-C3N4 composite catalyst was prepared via hydrothermal synthesis to activate peroxymonosulfate (PMS), degrade OPs (e.g., glyphosate), and selectively adsorb IPs. The system demonstrated robust performance, rapidly converting glyphosate into recoverable IPs. Even in complex aqueous matrices, this system delivered exceptional stability and catalytic performance, affording 87.9% glyphosate degradation within 40 min at an initial glyphosate concentration of 10 mg/L, alongside a high inorganic phosphate recovery of 84.3%. Moreover, the IP fertilizer recovered from simulated wastewater in a continuous-flow reactor exhibited excellent growth-promoting effects on crops in agricultural validation tests. Mechanistic studies revealed that ultrathin g-C3N4 nanotubes act as an electron-transfer medium, mediating electron transfer between glyphosate and PMS and activating PMS to generate reactive species composed mainly of SO4•- and •O2-, which convert glyphosate into IPs. Meanwhile, the high-density Mg2+ ions exposed on the (200) crystal plane of MgO can form stable magnesium phosphate precipitates with the IPs generated during degradation. This technology enables the continuous degradation of OPs while simultaneously adsorbing and immobilizing IPs, thereby transforming pollutants into potential nutrients and mitigating aquatic toxicity.
