title: Supported Pd/Sn bimetallic nanoparticles for reductive dechlorination of aqueous trichloroethylene.
abstract: A Pd/Sn bimetallic nanoparticles resin (nano-Pd/Sn/resin) was successfully synthesized for reductive transformation of aqueous trichloroethylene (TCE). The physicochemical properties of the prepared resin were characterized using scanning electron microscopy, energy dispersive X-ray spectroscopy, N(2) isothermal sorption at and X-ray photospectroscopy. The surface-area-normalized rate constants (k(SA)) of Sn particles in the nanoscale range (50-100 nm) were 4.5 times larger than the k(SA) for powdered Sn (0.04 mm). After depositing 1 wt% Pd onto nano-Sn surface, k(SA) was further enhanced by about a factor of 2. Groundwater constituents such as sulfide nitrate and dissolved oxygen had significant negative effects on the rate of TCE degradation by the nano-Pd/Sn/resin. A wet-chemical method regeneration method was observed to effectively restore the reactivity of the poisoned nano-Pd/Sn/resin after dipping in sulfide solution for 2d. In all cases, less than 0.5% of the degraded TCE appeared as chlorinated byproducts including the three dichloroethene isomers. The nano-Pd/Sn/resin technique performs well in transforming TCE into nontoxic hydrocarbons, as compared with other published methods.
authors.affiliation: Research Center for Environmental Pollution Prevention and Control Technology, Graduate Institute of Environmental Engineering, National Taiwan University, 71, Chou-Shan Road, Taipei 106, Taiwan, ROC.
authors.forename: Chin Jung
authors.initials: CJ
authors.lastname: Lin
authors.forename: Ya Hsuan
authors.initials: YH
authors.lastname: Liou
authors.forename: Shang-Lien
authors.initials: SL
authors.lastname: Lo
mesh_terms: D002713:Chlorine / Q000737:chemistry*; D052918:Environmental Restoration and Remediation / Q000379:methods; D008855:Microscopy, Electron, Scanning; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010084:Oxidation-Reduction; D010165:Palladium / Q000737:chemistry*; D014001:Tin / Q000737:chemistry*; D014241:Trichloroethylene / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry; D018508:Water Purification / Q000379:methods; D014881:Water Supply / Q000032:analysis
chemical_list: D014874:Water Pollutants, Chemical; D014241:Trichloroethylene; D002713:Chlorine; D010165:Palladium; D014001:Tin