阴-阳离子有机膨润土制备及其吸附Cr(Ⅵ)的影响因素研究

Research on preparation of anion-cation organic bentonite and affecting factors of Cr(Ⅵ) absorption

本文采用十六烷基三甲基溴化铵（CTMAB）和十二烷基硫酸钠（SDS）对辽宁黑山膨润土进行不同工艺的阴-阳离子有机膨润土制备,探讨了阴-阳离子有机膨润土对Cr（Ⅵ）的吸附机理,并利用正交实验分析了各实验因子对Cr（Ⅵ）吸附效果的影响,为污染地下水修复技术PRB提供一种新的反应介质和技术参数。研究结果表明：阴-阳离子有机膨润土（Na-R-ACOMMT）吸附Cr（Ⅵ）是物理吸附和化学吸附联合作用的结果;pH值和投加量是影响Na-R-ACOMMT对Cr（Ⅵ）吸附效果的2个最主要的因素,尤其是pH值;Na-R-ACOMMT吸附Cr（Ⅵ）的最佳条件是投加10g/l 60-80目的样品,在40℃、pH值等于2、150r/min的环境下振荡60min,Cr（Ⅵ）去除率高达93.55%,且吸附等温线符合Langmuir和Freundlich方程。

In this paper, Liaoning Heishan bentonite was made into anion-cation organic bentonite through different processes by adding CTMAB and SDS. the Cr（ Ⅵ ） absorption mechanism of anion-cation organic bentonite was discussed, and the effect of every experiment factor on Cr（ Ⅵ ） absorption was analyzed by the orthogonal test, which supplied one kind of new reaction medium and technical parameter of the anion-cation organic bentonite used in the new PRB technique of polluted groundwater remediation. The studying result is indicated： Cr （Ⅵ） absorption of anion-cation organic bentonite（Na-R-ACOMMT） is the co-action of physical absorption and chemical absorption; pH and adding amount are the most important factors for the absorption effect, especially pH; the optimal conditions for Na-R-ACOMMT adsorbing Cr（Ⅵ ） are sample amount of 10g/L, 60 - 80, 40℃ , pH of 2 and oscillating for 60 min with a frequency of 150 r/min. Under this condition, the absorption rate is high to 93.55%, and the absorption isotherm accords with Langmuir and Freundlich equation.