title: Chloride ions promoted the catalytic wet peroxide oxidation of phenol over clay-based catalysts.
abstract: Catalytic wet peroxide oxidation (CWPO) of phenol over clay-based catalysts in the presence and absence of NaCl was investigated. Changes in the H2O2, Cl(-), and dissolved metal ion concentration, as well as solution pH during phenol oxidation, were also studied. Additionally, the intermediates formed during phenol oxidation were detected by liquid chromatography-mass spectroscopy and the chemical bonding information of the catalyst surfaces was analyzed by X-ray photoelectron spectroscopy (XPS). The results showed that the presence of Cl(-) increased the oxidation rate of phenol to 155%, and this phenomenon was ubiquitous during the oxidation of phenolic compounds by H2O2 over clay-based catalysts. Cl(-)-assisted oxidation of phenol was evidenced by several analytical techniques such as mass spectroscopy (MS) and XPS, and it was hypothesized that the rate-limiting step was accelerated in the presence of Cl(-). Based on the results of this study, the CWPO technology appears to be promising for applications in actual saline phenolic wastewater treatment.
authors.affiliation: National Engineering Laboratory for Improving Quality of Arable Land, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China E-mail: xuminggang@caas.cn.
authors.forename: Shiwei
authors.initials: S
authors.lastname: Zhou
authors.affiliation: Ministry of Agriculture, Ago-Environmental Protection Institute, Tianjin 300191, China.
authors.forename: Changbo
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Chemistry & Chemical Engineering College, Yantai University, Yantai 264005, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Xu
authors.affiliation: Chemistry & Chemical Engineering College, Yantai University, Yantai 264005, China.
authors.forename: Chuantao
authors.initials: C
authors.lastname: Gu
authors.affiliation: Ministry of Agriculture, Ago-Environmental Protection Institute, Tianjin 300191, China.
authors.forename: Zhengguo
authors.initials: Z
authors.lastname: Song
authors.affiliation: National Engineering Laboratory for Improving Quality of Arable Land, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China E-mail: xuminggang@caas.cn.
authors.forename: Minggang
authors.initials: M
authors.lastname: Xu
mesh_terms: D000538:Aluminum Silicates / Q000737:chemistry*; D002384:Catalysis; D002712:Chlorides / Q000737:chemistry*; D000077215:Clay; D006861:Hydrogen Peroxide / Q000737:chemistry*; D010084:Oxidation-Reduction; D019800:Phenol / Q000737:chemistry*; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical
chemical_list: D000538:Aluminum Silicates; D002712:Chlorides; D000077215:Clay; D006861:Hydrogen Peroxide; D019800:Phenol; D062065:Wastewater; D014874:Water Pollutants, Chemical