高锰酸钾吸收气态汞的传质-反应研究

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.

Mass transfer-reaction of Hg0 absorption in potassium permanganate

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 Hg0 concentration and temperature on Hg0 removal efficiency were investigated,as well as the thermodynamics and mass transfer-reaction between Hg0 and KMnO4.The results showed that both increasing the KMnO4 concentration and using acidic or alkaline solution promoted the removal of Hg0.The reasons are that H2 SO4 in solution facilitates the adsorption of Hg0 on MnO2,and that free radical OH produced in alkaline solution can oxidate Hg0.High temperature has a negative effect on the removal of Hg0,and the effect of Hg0 initial concentration can be neglected.The oxidation of Hg0 by KMnO4 is a two-order reaction and the activated energy is 27.22 kJ/mol.