PDMDAAC与一氯胺的反应动力学研究

Kinetics of NDMA Formation From PDMDAAC with Monoc-hloramine

摘要:

以我国微污染原水的预氯氧化和复合混凝剂强化混凝过程条件为背景，以聚二甲基二烯丙基氯化铵（PDMDAAC）与一氯胺反应生成消毒副产物NDMA的过程为对象，采用隔离法和初始浓度法，在15~35℃间，研究了二者反应的初始阶段、PDMDAAC开环降解反应过程的动力学。结果表明：对于PDMDAAC与一氯胺的反应，总反应级数均在1.99以上，接近于2，对反应物一氯胺和PDMDAAC的反应级数均在0.9971以上；相关系数R2均＞0.9976。25℃时，反应速率常数为1.23×10-5L/(mol•h)，在15~35℃间反应活化能Ea约为44.22kJ/mol。由此得到了PDMDAAC与一氯胺反应生成消毒副产物N, N-二甲基亚硝胺初始过程的动力学描述。

Abstract:

The conditions of coagulation process and of tiny-polluted raw water in China were taken as a background, the preliminary degradation of Poly(dimethyldiallylammonium) chloride（PDMDAAC）reacting with mono-chloramine, finally to form disinfection by product NDMA was taken as the research object, the reaction kinetics of mono-chloramine and PDMDAAC were studied by means of initial reactant concentration and isolation independently within a range of temperature 15~35℃in this paper. The results showed that the general reaction order was conformed to be more than 1.99, closed to 2; the reaction order for mono-chloramine and PDMDAAC were all more than 0.9971, and coefficient of correlation R2 was more than 0.9971. The reaction rate constant was 1.23×10-5L/(mol•h) at 25℃.And the reactive activation energy Ea was 44.22kJ/mol, approximately. Thus, the kinetics research on the starting stage of PDMDAAC reacting with mono-chloramine to form NDMA was completed.