菱铁矿催化过氧化氢-过硫酸钠修复地下水中1,2-二氯乙烷污染

采用菱铁矿催化过氧化氢-过硫酸钠双氧化剂体系去除地下水中的1,2-二氯乙烷,通过研究菱铁矿催化机理以及氧化剂浓度两方面探讨双氧体系较单氧体系有较高去除率的原因,探讨了双氧体系1,2-DCA降解动力学和氯离子平衡。研究结果表明,菱铁矿催化双氧体系可以有效去除溶液中的1,2-DCA,本体系条件下去除率可达到95%以上。其较低的pH,较高Fe2+浓度,较高自由基生成量和氧化剂浓度,使得双氧体系较Fenton-Like体系有较高1,2-DCA去除率。菱铁矿催化双氧体系去除1,2-DCA反应过程中有中间产物生成,但最终完全脱氯,没有中间产物残留。

Removal of 1,2-dichloroethane in groundwater with siderite-catalyzed hydrogen peroxide and persulfate system

The process of siderite-catalyzed hydrogen peroxide and persulfate to remove 1,2-dichloroethane in groundwater was studied.The catalytic mechanism and the concetration of radical and oxidants were investigated to explain the higher removal rate of the double oxidation system than that in Fenton-Like system.The reaction kinetic of 1,2-DCA degradation and the balance of Cl^- were discussed.Experimental results show that catalyzed hydrogen peroxide and persulfate by siderite can remove the 1,2-DCA effectively.The removal rate was over 95%.The lower pH,higher concentration of Fe²⁺,higher concentration of radicals and oxidant leaded to the higher removal rate in the double oxidation system than that in Fenton-Like system.The chlorine derived from 1,2-DCA did not reach balance at first but reached balance at last,indicating that intermediates generated in the process but dechlorinated completely at the end of the reaction.