THE ROLE OF OXIDE FILMS IN THE REDUCTION OF N - NITROSODIMETHYLAMINE WITH REFERENCE TO THE IRON GROUNDWATER REMEDIATION TECHNOLOGY

摘要

The reduction of N-nitrosodimethylamine (NDMA) by low - alloy scrap iron material was studied in column and batch experiments at open circuit potential. The results were compared with the results obtained from differential pulse voltammetry and exhaustive electrolysis on a mercury electrode. The results show that (1) electroreduction of NDMA occurs at potentials more negative than - 1.3 V (SHE) and this potential can not be achieved under the column and batch experimental conditions; (2) different reduction products of NDMA were observed in electroreduction experiments compare to the column and batch experiments. Results show that in the case of iron material and NDMA only catalytic hydrogenation can account for all experimental observations. Despite the experimental evidence of autoreduction of the outer surface film of Fe_2O_3 and existence of magnetite, the role of magnetite in the catalytic process is not sufficiently understood.