载铁改性膨润土处理含 Cr（Ⅵ）废水试验研究

摘要

The bentonite was modified by loading iron then used to adsorb Cr (Ⅵ ) in wastewater .The effects of pH ,temperature ,adsorption time and amount of Fe‐immobilized bentonite on adsorption rate of Cr (Ⅵ ) by static adsorption experiment were examined .The composition changes of bentonite before and after modifying and adsorption of mechanism for Cr (Ⅵ ) by scanning electrion microscope (SEM ) and fourier transform infrared spectra (FTIR) were analyzed .The results show that the specific surface areas of Fe‐immobilized bentonite increase tremendously ,the adsorption capacity of Cr(Ⅵ) in wastewater is very high .The pH of wastewater affects obviously the adsorption rate of Fe‐immobilized bentonite for Cr(Ⅵ) ,and the maximal adsorption rate is over 85 .8% when the pH is to 6 .The adsorption mechanism of the Fe‐immobilized modified bentonite for Cr(Ⅵ) is complex reaction with hydroxyl group and ion‐exchange .%以载铁方式对膨润土进行改性，并通过静态吸附试验考察溶液pH、温度、吸附时间、改性膨润土用量对Cr（Ⅵ）吸附率的影响；借助SEM及FTIR分析改性前后的膨润土吸附Cr（Ⅵ）后的组成变化及吸附机制。结果表明：膨润土载铁改性后，比表面积大大增加，更有利于吸附废水中的Cr（Ⅵ）；溶液pH对Cr（Ⅵ）吸附率影响最大，pH＝6时，Cr（Ⅵ）吸附率达85．8％；改性膨润土对Cr（Ⅵ）的吸附机制主要是与Cr（Ⅵ）发生羟基配合反应及离子交换反应。