00000nam 2200000zi 4500 9.871751 CaOODSP 20241203113648 m o d f cr ||||||||||| 190417s1996 oncad #ob f000 0 eng d CaOODSP eng rda CaOODSP En13-5/96-84E-PDF Lesage, Suzanne, author. Investigation of the reaction mechanism of the reductive dechlorination of chlorinated solvents by vitamin B12 using spin-trapping GC/MS and LC/MS / by Suzanne Lesage and Susan Brown. Burlington, Ontario, Canada : Environment Canada, Water Science and Technology Directorate = Environnement Canada, Direction générale des sciences et de la technologie, eau, [1996?] 1 online resource (20 pages) : illustrations, graphs. text txt rdacontent computer c rdamedia online resource cr rdacarrier NWRI contribution ; 96-84 Title from cover. Digitized edition from print [produced by Environment and Climate Change Canada]. Includes bibliographical references. "Vitamin B12 has been suggested as a biochemical catalyst for the reductive dechlorination of chlorinated solvent such as carbon tetrachloride and tetrachloroethylene which are common groundwater pollutants. However, much remained to be understood as to the mechanism of the reaction and the environmental conditions that are likely to be able to sustain the reaction. In this project, the reactivity of vitamin B12 with a variety a reducing agents was examined and the resulting intermediates studied by LC-MS. It was found that sodium dithionite disproportionates to bisulfite which adds itself to the 2- benzimidazole ring of vitamin B12, producing an inactive molecule. It was found that the reversibility of the reduction was one of the most critical factors in the suitability of a reducing agent and that amongst all those readily available, titanium citrate was the reagent of choice for enviromnental applications. Spin-trapping GC/MS, using phenyl-tert-butyl nitrone as a spin trap, was used as an investigative tool to confirm the formation of several free radicals during the reductive dechlorination of carbon tetrachloride and of tetrachloroethylene"--Abstract. gccst Biochemicals gccst Groundwater gccst Pollutants Brown, Susan, author. Canada. Environment Canada. Canada. Water Science and Technology Directorate. NWRI contribution ; 96-84. (CaOODSP)9.844121 PDF 2.36 MB https://publications.gc.ca/collections/collection_2019/eccc/en13-5/En13-5-96-84-eng.pdf