高锰酸钾吸收气态汞的传质-反应研究  

Mass transfer-reaction of Hg^0 absorption in potassium permanganate

作　　者：叶群峰[1] 王成云[1] 徐新华[1] 汪大翚[1] 

机构地区：[1]浙江大学环境工程学系,浙江杭州310027

出　　处：《浙江大学学报（工学版）》2007年第5期831-835,870,共6页Journal of Zhejiang University：Engineering Science

基　　金：国家自然科学基金资助项目(20476094)

摘　　要：为了考查氧化剂高锰酸钾吸收气体态元素汞Hg0的行为,在鼓泡反应器中,通过改变各种影响因素,采用冷原子吸收(CVAA)测汞仪测定了反应器进口和出口的气态汞浓度.系统地研究了高锰酸钾初始浓度、pH值、汞初始度和反应温度等主要参数对气态汞去除效率的影响,并分析了KMnO4氧化Hg0的反应热力学和传质-反应动力学问题.研究结果表明,高猛酸钾初始浓度的增加、强酸或强碱条件均有利于Hg0的去除,H2SO4的存在促进了Hg0在MnO2上的吸附,而强碱水溶液中产生的OH间接氧经了Hg0;反应温度的升高抑止了Hg0的去除,而Hg0初始质量浓度对反应的影响可忽略;KMnO4氧化Hg0的反应为二级反应,活化能为27.22 kJ/mol.The conditions for potassium permanganate oxidizing gaseous mercury were examined. Gaseous mercury concentration at the inlet and outlet of a bubble column reactor was measured by cold vapor atom absorption （CVAA） mercury analyzer. The effects of KMnO4 concentration, pH value, initial Hg^0 concentration and temperature on Hg^0 removal efficiency were investigated, as well as the thermodynamics and mass transfer-reaction between Hg^0 and KMnO4. The results showed that both increasing the KMnO4 concentration and using acidic or alkaline solution promoted the removal of Hg^0. The reasons are that H2 SO4 in solution facilitates the adsorption of Hg^0 on MnO2, and that free radical OH produced in alkaline solution can oxidate Hg^0. High temperature has a negative effect on the removal of Hg^0 , and the effect of Hg^0 initial concentration can be neglected. The oxidation of Hg^0 by KMnO4 is a two-order reaction and the acti- vated energy is 27.22 kJ/mol.

关 键 词：高锰酸钾 气态汞 吸收 传质-反应 

分 类 号：TQ150.9[化学工程—电化学工业] X783[环境科学与工程—环境工程]