二甲胺盐酸盐与氯胺生成NDMA动力学研究

研究了二甲胺盐酸盐与氯胺反应生成N，N-亚硝基二甲胺（NDMA）的动力学.采用隔离法测定得到反应物浓度与时间的变化关系，进而采用尝试法求解反应级数、速率常数、速率方程和活化能.结果表明：对于二甲胺盐酸盐与氯胺反应生成中间体的第一步过程，反应物两者的反应级数均为一级，反应速率常数在5，15和25℃下分别为1.5361×10^-3，1.8707×10^-3，7.7217×10^-3mol^-1·min^-1，反应活化能Ea为51.27kJ/mol.由反应速率常数和活化能数值可以看出温度高有利于反应的进行.所得结果可为含二甲胺基及其同系物与氯胺整体反应的动力学研究，以及原水处理过程中消毒副产物NDMA生成风险的判定提供实验依据.

Kinetics of NDMA formation from dimethylaminehydrochlorate reacted with chloramine

The kinetics of NDMA formation from dimethylamine hydrochlorate reacted with chloramine were studied. The correlation between the reactant concentration and reacting time was measured by the isolation method, and then the order of reaction, the reaction rate constant, and rate equation as well as the activation energy of dimethylamine hydrochlorate reacted with chloramine were obtained by the tentative method. The reaction of dimethylamine hydrochlorate with chloramine in first step to form an intermediate was second order and first order for both the salt and chloramine. The rate constants of dimethylamine hydrochlorate reacted with chloramines were 1.5361×10^-3, 1.8707×10^-3 and 7.7217×10^-3mol^-1·min^-1 at 5, 15 and 25℃, respectively. The reaction activation energy Ea was 51.27kJ/mol. The observed rate constants and the activation energy suggested that the reaction was better under high temperatures. Our results could provide experimental data for the reaction kinetics of dimethylamine and its derivatives with chloramines to form NDMA, and for the risk analysis of NDMA as disinfection by-products in the raw water treatment.