The role of Cu(II) in the reduction of N-nitrosodimethylamine with iron and zinc

Simultaneous Adsorption and Electrochemical Reduction of N-Nitrosodimethylamine Using Carbon-Ti4O7 Composite Reactive Electrochemical Membranes

“…The addition of carbonaceous materials allowed for increased residence times of NDMA in the reactor by a factor of 3.8 to 5.4 and therefore enabled electrochemical reduction to be a feasible approach for NDMA destruction. The reduction products of DMA and NO 3 – /NH 4 + do not pose a health risk at these low levels. − Prior studies required the addition of chemicals (e.g., UV/iodide, H 2 O 2 , H 2 ) or precious metal catalysts (e.g., Pd, Pt) for efficient NDMA removal, and signficant removal (e.g., > 99%) was only achieved in batch reactors with reaction times on the order of 10s of minutes to several hours. ,,, Electrochemical oxidation with the PAC-REM was shown to not be an effective remediation method due to slow reaction kinetics and parasitic oxidation of the carbon content.…”

“…Research has focused on various methods for the removal of NDMA from water and wastewater. These methods include separation methods, such as reverse osmosis (RO), and destructive methods, such as reductive catalysis and zerovalent iron (ZVI), − advanced oxidation processes (AOPs), − and direct UV photolysis. , All these methods have limitations such as poor rejection by RO, high operating costs for RO, AOPs, and UV photolysis, high capital costs and fouling by natural water species for precious metal catalysts, , and low reaction rates with ZVI. , Moreover, methods to limit the formation of NDMA by removing NDMA precursors has also been extensively studied, with some promising results …”

Electrochemically Mediated Reduction of Nitrosamines by Hemin-Functionalized Redox Electrodes

“…Also, when normalized by the mass of the catalyst loading, the estimated equivalent zero-order rate constants of our hemin–CNT catalysts [50 mmol min –1 (g of catalyst) −1 ] are approximately an order of magnitude higher than those observed with state-of-the-art Pd-supported chemical catalysts; this result is encouraging as the earth abundance of iron and the wide availability of hemin as a catalyst point to the better cost effectiveness of our systems relative to others in the literature. Furthermore, hemin–CNT catalysts can sustain mass-based rate constants that are close to 2 orders of magnitude higher than those of many non-noble bulk metal catalysts such as iron or zinc alloys . This high stoichiometric conversion displayed by hemins is a hallmark of metal complex inorganic and enzyme catalysts, allowing highly selective organic transformations caused by their unique electronic structures.…”

“…Furthermore, hemin−CNT catalysts can sustain mass-based rate constants that are close to 2 orders of magnitude higher than those of many non-noble bulk metal catalysts such as iron or zinc alloys. 35 This high stoichiometric conversion displayed by hemins is a hallmark of metal complex inorganic and enzyme catalysts, allowing highly selective organic transformations caused by their unique electronic structures. The mechanism of nitrosamine electroreduction of nicotinederived nitrosamine ketone (NNK) and N-nitrosonornicotine (NNN), which play important roles in carcinogenesis in aqueous acidic media, was elucidated using MALDI-TOF and ESI spectrometry.…”

Disinfection byproduct formation during drinking water treatment and distribution: A review of unintended effects of engineering agents and materials

“…To understand the fate of DBPs in DWDSs and to develop possible treatment processes for removal of DBPs from drinking water, numerous studies have focused on degradation of representative DBPs (i.e. THMs, HAAs, HALs, HKs, HANs, HNMs, HAMs and NAs) in the presence of zerovalent metals (Gui et al, 2000;Hozalski et al, 2001;Zhang et al, 2004;Pearson et al, 2005;Lee et al, 2007;Arnold et al, 2010;Wang and Zhu, 2010;Han et al, 2013;Tang et al, 2015;Chu et al, 2016c;Han et al, 2017). Table 3 presents the experimental conditions and results for the reactions of DBPs with different elemental metals.…”