A mechanistic investigation of the oxidation of N,α-diphenylnitrones by dichloramine-T in aqueous acetonitrile medium - a non-linear Hammett plot (original) (raw)
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N-nitrosodimethylamine (NDMA) is a potent carcinogen and frequently detected nitrosamine from water chloramination. This study investigated the effects of pre-oxidation on the reduction of NDMA formation potential (FP) from ranitidine (RNT) upon subsequent chloramination. Reactive chlorine species (RCS) were generated by employing a coated titanium anode with IrO2 -Ta2O5 and a titanium plate as a cathode material. The TiO2 photocatalyst was immobilized by electrospraying TiO2 dispersion on stainless-steel mesh. In addition, the effects of competing NDMA precursors on the NDMA FP of RNT was examined. Reduced NDMA FP values of RNT in the presence of co-existing compounds might be ascribed to competing reactions and NH2Cl demand. In the presence of N,N-diethyhydroxylamine, complete inhibition of NDMA FP resulted from the depletion of dissolved oxygen. Pre-chlorination was found to effectively mitigate NDMA FP, depending on the applied [RCS]0, duration, and pH. The NDMA FP of RNT decrea...
International Journal of Engineering Research and Technology (IJERT), 2012
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