title: The activity and selectivity of catalytic peroxide oxidation of chlorophenols over Cu-Al hydrotalcite/clay composite.
abstract: Liquid phase catalytic oxidation of chlorophenols (CPs) was carried out over Cu-Al hydrotalcite/clay composite at ambient temperature and pressure using hydrogen peroxide as oxidant. The results showed that the catalyst had high catalytic activity, with complete oxidation of 4-CP within 40 min at 40 °C. The content and position of chlorine on the aromatic ring had significantly different effects on the oxidation rate of CPs, with the rate sequence of phenol > monochlorophenol (MCP) > dichlorophenol (DCP) > trichlorophenol (TCP), 3-CP > 2-CP > 4-CP, and 3,5-DCP > 3,4-DCP > 2,5-DCP > 2,4-DCP > 2,6-DCP. This was ascribed to the interactions among σ-electron withdrawing conductive effect, π-electron donating conjugative effect, and steric hindrance effect of chlorine. It was evidenced that the catalytic peroxide oxidation of CPs in the first step was selective and rate-limiting, where chlorinated 1,4-benzoquinones formed.
authors.affiliation: Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China.
authors.forename: Shiwei
authors.initials: S
authors.lastname: Zhou
authors.forename: Chuantao
authors.initials: C
authors.lastname: Gu
authors.forename: Zhenying
authors.initials: Z
authors.lastname: Qian
authors.forename: Jinguang
authors.initials: J
authors.lastname: Xu
authors.forename: Chuanhai
authors.initials: C
authors.lastname: Xia
mesh_terms: D000535:Aluminum / Q000737:chemistry*; D000536:Aluminum Hydroxide / Q000737:chemistry*; D000538:Aluminum Silicates / Q000737:chemistry*; D002384:Catalysis; D002733:Chlorophenols / Q000737:chemistry*; D000077215:Clay; D003300:Copper / Q000737:chemistry*; D008276:Magnesium Hydroxide / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D010084:Oxidation-Reduction; D010545:Peroxides / Q000737:chemistry*
chemical_list: D000538:Aluminum Silicates; D002733:Chlorophenols; D010545:Peroxides; C010467:hydrotalcite; D000536:Aluminum Hydroxide; D003300:Copper; D000535:Aluminum; D008276:Magnesium Hydroxide; D000077215:Clay