卟啉锰电催化还原降解滴滴涕

Electrocatalysis reductive degradation of DDT using manganese porphyrins

利用循环伏安及紫外-可见光谱电化学方法,研究了八乙基卟啉锰和四苯基卟啉锰在DMF中电还原降解滴滴涕(DDT)的催化性质.结果表明,中性和第1级还原的卟啉锰对DDT的降解无催化作用,而第2级和第3级电还原的配合物均能催化DDT的降解反应.利用控制电位技术,以卟啉锰为电催化剂,对DDT进行了还原降解,利用气相色谱-质谱联用技术对降解产物进行了分析鉴定.在试验条件下,DDT降解的主要产物为1,1-二(4-氯苯基)-2,2-二氯乙烷(DDD),1,1-二(4-氯苯基)-2,2-二氯乙烯(DDE)和1,1-二(4-氯苯基)-2-氯乙烯(DDMU).根据试验结果提出了卟啉锰配合物电催化还原降解DDT的机理.

The catalytic properties of octaethylporphyrin and tetraphenylporphyrin manganese complexes on degradation of DDT were examined by cyclic voltammetry and UV-visible spectroelectrochemistry in DMF.No catalytic reaction was observed for DDT by neutral and first reduced manganese porphyrins,but both doubly and triply reduced complexes can catalyze the degradation of DDT.The electroreductive de-gradation of DDT was performed by using a technique of controlled-potential electrolysis and manganese porphyrins as the electrocatalysts.The products of DDT degradation were analyzed and characterized by the GC-MS technique.The main products of DDT degradation are DDD（1,1-bis（4-chlorophenyl）-2,2-dichloroethane）,DDE（1,1-bis（4-chlorophenyl）-2,2-dichloroethylene） and DDMU（1,1-bis（4-chlorophenyl）-2-chloroethylene） under the given experimental conditions.Based on the experimental results,a mechanism for reductive degradation of DDT catalyzed by manganese porphyrins was proposed.