| The pollutant N,N-dimethylacetamide (DMAC) originated from chemical fiber factory was pretreated by internal microelectrolysis. The influencing factors such as pH, the volumetic ratio of iron to activated carbon, the diameter of the activated carbon, and the hydraulic retention time were explored, and optimum operational conditions were confirmed. The results showed: when the raw wastewater concentration was 50mg·L-1, the optimum conditions were pH=3.0, Fe/C=1:1, and HRT=60min, under which the removal rate of DMAC was above 95%.Kinetics and degradation mechanism of this pollutant were studied by comparing the results of the every kind of products and the structure of sponges. The results showed: the removal mode of DMAC basically conformed to the rule of second order kinetics; the DMAC was mainly removed by activated carbon adsorption, followed by the electrolytic reaction. The ammonic-nitrogen and ferrous iron were measured, the concentration of them were 0.42 mg·L-1 and 25 mg·L-1, respectively. Besides, a small amount of ferric iron was tested. Electro-adsorption and physical adsorption didn't take effects in the system. There was also weakly Fe(OH)3 coagulation action. In a word, the removal of DMAC was carried out with the effects of several reaction mechanisms, approximately 90% of activated carbon adsorption as well as 10 % of redox reaction.
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