Removal of EDTA-Cu(II) from Water Using Synergistic Fenton Reaction-Assisted Adsorption by Nanomanganese Oxide-Modified Biochar: Performance and Mechanistic Analysis
Ying Zhu, Wenhong Fan, Weiying Feng, Ying Wang, Shu Liu, Zhaomin Dong, Xiaomin Li
Abstract
Metal complexes exhibit higher stability in water, making metal removal more challenging. In this study, a low-cost, high-efficiency, and multifunctional nanomanganese oxide-modified biochar (BC-MnOx) was used for synergistic adsorption processes and Fenton reaction catalysis to achieve the removal of EDTA-Cu(II). Using this system, the Cu and total organic carbon removal efficiencies reached 94.67% and 92.79%, respectively. Mechanistic analysis indicated that multifunctional BC-MnOx catalyzed the Fenton reaction to generate hydroxyl radicals (HO•) capable of attacking the EDTA-Cu(II) complex structure and releasing low-molecular weight organic matter-Cu compounds due to the simultaneous decarboxylation at different positions, which were concurrently adsorbed by modified biochar. The modified biochar assessed in this study offers high-efficiency Cu complex removal, high stability, low cost, and widespread availability, laying a promising foundation for its practical applicability and potential suitability for the removal of other metal complexes.