title: Electrochemical removal of haloacetic acids in a three-dimensional electrochemical reactor with Pd-GAC particles as fixed filler and Pd-modified carbon paper as cathode.
abstract: The reductive removal of haloacetic acids (HAAs) in a three-dimensional electrochemical continuous reactor with Pd-granular activated carbon (Pd-GAC) particles as fixed filler and Pd-modified carbon paper (Pd-C) as cathode was studied in this research. Pd-C electrode was prepared from PdCl2 via electrodeposition onto carbon paper. Pd-GAC particles were prepared by the impregnation of Pd(2+) ions onto GAC. Efficient electrocatalytic reduction of HAAs in this reactor was exhibited. Effects of current density, initial HHAs concentration, and hydraulic retention time on the HHAs removal were investigated. Under the current density of 0.3 mA/cm(2), HAAs with initial concentration of 120 μg/L were reduced to be less than 60 μg/L with hydraulic retention time of 20 min. Electron transfer and HAAs diffusion both played an important role in controlling the electro-reduction process under the conditions of current density less than 0.6 mA/cm(2) with an initial HAAs concentration ranging from 120 to 600 μg/L. However, the HAAs diffusion became the primary rate-limiting step when the current density was higher than 0.6 mA/cm(2). The Pd(0) and Pd(2+) species were detected by X-ray photoelectron spectroscopy. The stability of the electrochemical reactor in the reduction removal of HAAs was also exhibited.
authors.affiliation: State key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Xu
authors.initials: X
authors.lastname: Zhao
authors.affiliation: State key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; China Academy of Urban Planning and Design, Beijing 100044, China.
authors.forename: Angzhen
authors.initials: A
authors.lastname: Li
authors.affiliation: State key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Ran
authors.initials: R
authors.lastname: Mao
authors.affiliation: State key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Huijuan
authors.initials: H
authors.lastname: Liu
authors.affiliation: State key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. Electronic address: jhqu@rcees.ac.cn.
authors.forename: Jiuhui
authors.initials: J
authors.lastname: Qu
mesh_terms: D000085:Acetates / Q000737:chemistry / Q000302:isolation & purification*; D002606:Charcoal; D055664:Electrochemical Techniques / Q000379:methods*; D004566:Electrodes; D006219:Halogens / Q000737:chemistry / Q000302:isolation & purification*; D010165:Palladium; D056951:Photoelectron Spectroscopy; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods*
chemical_list: D000085:Acetates; D006219:Halogens; D014874:Water Pollutants, Chemical; D002606:Charcoal; D010165:Palladium
keywords: Electrocatalytic reduction; Haloacetic acids; Pd-C electrode; Pd-GAC; Three-dimensional electrochemical reactor