有机改性膨润土用于含铬废水处理和铬污染土壤修复的探究

用有机改性剂十六烷基三甲基溴化铵（CTMAB）对钠基膨润土进行改性，研究了钠基膨润土改性前后对废水中Cr（Ⅵ）的吸附效果。探讨了吸附时间、溶液pH、膨润土投加量、吸附温度等对吸附效果的影响。实验得到钠基膨润土的最佳吸附条件：40 min、pH=7.0、15 g/L、20～30 ℃；改性膨润土的最佳吸附条件：40 min、pH=6.0、10 g/L、30 ℃。通过有机改性，吸附效果从50%显著提升至95%以上，表明改性膨润土对废水中Cr（Ⅵ）具有更好的去除效果。实验进一步探讨了改性膨润土对Cr（Ⅵ）的吸附规律，改性膨润土对Cr（Ⅵ）的吸附行为符合Langmuir方程，还初步考察了改性膨润土应用于铬污染土壤的修复效果，对铬污染土壤的修复效果明显优于钠基膨润土，去除率达90%以上。

Study on disposal of chromium wastewater and remediation ofchromium-contaminated soil by organo-bentonite

Na-based bentonite was modified with cetyl trimethyl ammonium bromide（CTMAB）as the modifier.The absorption efficiency of Na-bentonite to chromium ion（Ⅵ） in wastewater before and after organic modification was investigated.Theinfluences of absorption time，solution pH，feeding amount of bentonite，and temperature etc.on the absorption effect were studied.The optimal adsorption conditions for Na-based bentonite were obtained by experiment as follows：40 min，pH=7.0， 15 g/L，and 20～30 ℃；and for organic modified bentonite were as follows：40 min，pH=6.0，10 g/L，and 30 ℃.After modifica-tion the adsorption rate significantly increased from 50% to 95% above.Then the adsorption isotherms of organic bentonite was studied in chromium wastewater and proved the adsorption process met the Langmuir isotherm model.The remediation effect of organic modified bentonite applied to Cr（Ⅵ） contaminated soil was also investigated preliminarily.Results showedorganic modified bentonite′s remediation effect to Cr（Ⅵ） contaminated soil was obviously better than that of Na-basedbentonite and the removal rates could be up to 90% above.