Three-dimensional flower-like magnetic CoFe-LDHs/CoFe2O4 composites activating peroxymonosulfate for high efficient degradation of aniline. (15th May 2022) - Sheng, Jialing
Abstract: In this study, 3D flower-like magnetic CoFe-LDHs/CoFe2 O4 was prepared by a facile urea hydrothermal method and utilized to activate peroxymonosulfate (PMS) for degrading aniline (AN). CoFe-LDHs/CoFe2 O4 was systematically characterized to explore the relationship between its structure and catalytic performance. Compared with CoFe-LDHs synthesized by co-precipitation method, CoFe-LDHs/CoFe2 O4 exhibited three dimensional structure and larger specific surface, which could increase the degradation efficiency of AN markedly. 96% of 10 mg L −1 AN could be eliminated by 0.3 mM PMS and 50 mg L −1 CoFe-LDHs/CoFe2 O4 at initial pH 6 within 5 min and the total organic carbon (TOC) removal efficiency could be high to 52.8% in 30 min. CoFe-LDHs/CoFe2 O4 can be separated by a magnet easily due to its magnetism, which makes it avoid secondary pollution and provide convenience. After recycling six times, the degradation efficiency still maintained at 92.6%. Besides, CoFe-LDHs/CoFe2 O4 /PMS can degrade AN in practical water samples effectively. In addition, the possible mechanism of CoFe-LDHs/CoFe2 O4 /PMS system for the degradation of AN was proposed. The radical scavenging experiments confirmed that SO4 · -, HO· and O2 · - were involved and SO4 · - played a dominant role in the degradation of AN, and it was further proved by electron Paramagnetic Resonance (EPR) as well. Our findings can provide some new insights into the efficient and skillful design and application of heterogeneous catalyst for environmental remediation. Highlights: Flower-like magnetic CoFe-LDHs/CoFe2 O4 microsphere was prepared to activate PMS to degrade AN. CoFe-LDHs/CoFe2 O4 shows more excellent catalytic activity than CoFe-LDHs by co-precipitation. Synergistic effect of Co and Fe can provide increasing catalytic activity and depress leaching. CoFe-LDHs/CoFe2 O4 can be reused 6 times and applied for degrading AN in practical water samples.