title: Catalytic ozonation of sulfamethoxazole by composite iron-manganese silicate oxide: cooperation mechanism between adsorption and catalytic reaction.
abstract: A systematic investigation of the cooperation mechanism between adsorption and catalytic reaction during the catalytic ozonation of sulfamethoxazole (SMX) by composite iron-manganese silicate oxide (FMSO) was carried out in this work. Results showed that the total organic carbon (TOC) removal increased significantly from 27 % (sole-ozonation) to 79.8 % (FMSO catalytic ozonation). The presence of FMSO in the ozonation process effectively enhanced the ozone utilization efficiency and accelerated the transformation of ozone into hydroxyl radicals. The latter result was verified by the indirect method, using NaHSO3as the reductor, and the direct electron spin resonance (ESR) determination technology. The adsorption of SMX on FMSO was minimal (1.8 %). However, ozone rapidly converted SMX into various intermediates, which was exhibited by the much higher adsorption affinity on the surface of FMSO than that of SMX. The accumulation of various intermediates on the FMSO surface also increased their contact probability with the ·OH radicals generated by the ozone decomposition. The continuous interaction of intermediates with ·OH radicals could further promote the benign cycling of the release of adsorption sites and the succeeding adsorption/decomposition of ozone and intermediates on FMSO. This could be another reason for the higher and faster TOC removal rate.
authors: State Key Laboratory of Urban Water Resource and Environment, School of Municipal & Environmental Engineering, Harbin Institute of Technology, Harbin, 150090, China.
authors: Guoying
authors: G
authors: Gao
authors: State Key Laboratory of Urban Water Resource and Environment, School of Municipal & Environmental Engineering, Harbin Institute of Technology, Harbin, 150090, China.
authors: Jing
authors: J
authors: Kang
authors: State Key Laboratory of Urban Water Resource and Environment, School of Municipal & Environmental Engineering, Harbin Institute of Technology, Harbin, 150090, China. shenjimin@hit.edu.cn.
authors: Jimin
authors: J
authors: Shen
authors: State Key Laboratory of Urban Water Resource and Environment, School of Municipal & Environmental Engineering, Harbin Institute of Technology, Harbin, 150090, China. zhonglinchen@hit.edu.cn.
authors: Zhonglin
authors: Z
authors: Chen
authors: Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong.
authors: Wei
authors: W
authors: Chu
mesh_terms: D000327:Adsorption; D002384:Catalysis; D017665:Hydroxyl Radical / Q000737:chemistry; D007501:Iron / Q000737:chemistry*; D017895:Manganese Compounds / Q000737:chemistry*; D010126:Ozone / Q000737:chemistry*; D017640:Silicates / Q000737:chemistry*; D013420:Sulfamethoxazole / Q000032:analysis* / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry; D018508:Water Purification / Q000379:methods*
chemical_list: D017895:Manganese Compounds; D017640:Silicates; D014874:Water Pollutants, Chemical; C000615724:iron-manganese silicate oxide; D017665:Hydroxyl Radical; D010126:Ozone; D007501:Iron; D013420:Sulfamethoxazole
keywords: Adsorption; Catalytic ozonation; Catalytic reaction; Composite iron-manganese silicate oxide; Ozone; Sulfamethoxazole