title: Metal-catalyzed reduction of N-nitrosodimethylamine with hydrogen in water.
abstract: There is considerable need for the rapid destruction of N-nitrosodimethylamine (NDMA) in water because current alternative treatment methods are relatively inefficient. Powdered metal catalysts in conjunction with hydrogen gas showed notable potential for rapid destruction of N-nitrosodimethylamine (NDMA) in water. Palladium, copper-enhanced palladium, and nickel catalysts showed significant efficacy for NDMA reduction, with observed half-lives on the order of hours using 10 mg L(-1) catalyst metal. Other catalysts were screened because of their well-documented efficacy for reduction of halogenated hydrocarbons, including zerovalent iron, nickel-enhanced iron, nickel, and manganese. Starting with 100 microg L(-1) NDMA, a level observed at multiple field sites, pseudo-first-order kinetics were observed for all catalysts tested. No reaction intermediates were observed in any experiment; the amine group of NDMA was cleaved and reduced to dimethylamine with carbon balance in excess of 97%. Reductive catalysis may prove an efficient technology for mitigating the health risk posed by NDMA; this study provides the foundation for mechanistic and longevity research.
authors.affiliation: Department of Civil & Environmental Engineering, Stanford University, Stanford, California 94305-4020, USA.
authors.forename: Matthew G
authors.initials: MG
authors.lastname: Davie
authors.forename: Martin
authors.initials: M
authors.lastname: Reinhard
authors.forename: John R
authors.initials: JR
authors.lastname: Shapley
mesh_terms: D002384:Catalysis; D002853:Chromatography, Liquid; D004128:Dimethylnitrosamine; D005618:Fresh Water / Q000737:chemistry*; D006859:Hydrogen / Q000737:chemistry*; D007700:Kinetics; D013058:Mass Spectrometry; D009532:Nickel / Q000737:chemistry*; D009602:Nitrosamines / Q000737:chemistry*; D010084:Oxidation-Reduction; D010165:Palladium / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis*; D018508:Water Purification / Q000379:methods*
chemical_list: D009602:Nitrosamines; D014874:Water Pollutants, Chemical; D010165:Palladium; D009532:Nickel; D006859:Hydrogen; D004128:Dimethylnitrosamine