羟基铝改性有机膨润土对Cr(Ⅵ)吸附效果的研究  

Adsorption of Hexavalent Chromium onto Organic Bentonite Modified by Hydroxy Aluminum

作　　者：佘崇梅 刘惠芬[1] 郝建朝[1] 卢显芝[1] 石利军[1] 

机构地区：[1]天津农学院农学与资源环境学院,天津300384

出　　处：《天津农学院学报》2015年第3期18-23,共6页Journal of Tianjin Agricultural University

基　　金：天津市科技支撑计划项目"绿色团泊小城镇居住社区建设科技惠民综合示范"(13ZCZDSF02600);天津市高等学校科技发展基金计划项目"微生物絮凝剂对水稻吸收砷和镉调控机制研究"(20130513);天津市高校优秀青年教师资助计划"改性有机膨润土对铬(VI)吸附效果和吸附机制研究"(无编号)

摘　　要：采用羟基铝改性有机膨润土(organic bentonite modified by hydroxy aluminum,OBA),以提高改性有机膨润土(organic bentonite,OB)对Cr(Ⅵ)的吸附能力。探讨了OBA用量、温度和p H值对Cr(Ⅵ)吸附能力的影响,以及OBA对Cr(Ⅵ)的吸附热力学和吸附动力学过程。结果表明,OBA对Cr(Ⅵ)的吸附能力显著高于OB;温度越高,吸附能力越差,最佳温度为25℃左右;在酸性条件下,p H值对OBA吸附Cr(Ⅵ)的影响较小;在碱性条件下,随着p H值提高,其吸附率降低;OBA对Cr(Ⅵ)的吸附符合Langmuir吸附等温曲线,最大吸附量为14.992 5 mg·g-1;OBA对Cr(Ⅵ)的吸附动力学方程符合伪二级动力学方程;OBA吸附Cr(Ⅵ)后可以脱附再生,但是,脱附再生后,Cr(Ⅵ)的吸附能力降低。Hydroxy aluminum was used to modify organic bentonite to increase it＇s adsorption of Cr（Ⅵ）. Some factors, such as dosage of adsorbent, temperature and p H value which influence Cr（Ⅵ） removal were examined, and adsorption isotherm, adsorption dynamics, desorption and regeneration of OBA to Cr（Ⅵ） were studied. The results show that OBA has higher adsorption capacity than OB. The adsorption capacity of OBA decreases with the increase of temperature, and the optimum temperature is 25 ℃. The p H value has little influence on adsorption of Cr（Ⅵ） onto OBA in the acid condition, but the adsorption capacity of OBA decreases with the increase of p H value in the alkaline condition. The adsorption isotherms follow Langmuir equation, and the equation is 1/qe=0.136 6/Ce＋0.067（R^2=0.992 9）, the maximum adsorption capacity is 14.992 5 mg·g^-1. The adsorption dynamics follow the pseudo secondary dynamics equation, and the equation is t/qt=0.104t＋0.106（R2=0.999）. The adsorption capacity of OBA decreases after desorption and regeneration.

关 键 词：Cr(Ⅵ) 有机膨润土 改性 羟基铝 吸附 

分 类 号：X52[环境科学与工程—环境工程]