Simultaneous glyphosate degradation and phosphate recovery from wastewater using a nanoconfined CuLa@CNT catalyst

Organophosphorus herbicide (i.e. glyphosate) contaminated wastewaters pose significant environmental and ecological risks, exacerbating the global phosphorus crisis. In this study, we design and optimize a novel nanoconfined CuLa@CNT catalyst for the simultaneous catalytic degradation of GLP and recovery of phosphate from GLP-containing agricultural wastewater. Designed with copper oxide as the catalytic site and lanthanum oxide as the phosphate-adsorbing site within carbon nanotubes (CNT), the catalyst exhibited 100% degradation of GLP within 40 min and 100% phosphate adsorption within 90 min, under the initial GLP concentration of 20 ppm. The excellent reusability and tolerance to complex environmental conditions were demonstrated, and a GLP removal efficiency of 91.1% was attained even in actual agricultural drainage water, confirming its practical applicability. The detailed characterization confirmed the successful formation of the nanoconfined structure, where copper and lanthanum species were uniformly dispersed within the CNT channels. Theoretical calculations and electron paramagnetic resonance analysis revealed that the confined CNT structure not only favored the generation of reactive oxygen species (•OH, 1 O 2 ) but also promoted selective C P bond cleavage in GLP and adsorption of phosphate, thereby enhancing the selectivity for phosphate recovery over other organic intermediates, such as aminomethylphosphonic acid. This study provides a simple and highly effective method for addressing organophosphorus agricultural wastewater while simultaneously recovering valuable phosphate, contributing to sustainable water treatment and resource recycling.