高岭土的改性及其对Cr(Ⅵ)的吸附特性  

Modification of Kaolin and Its Adsorption Properties on Cr(Ⅵ)

作　　者：张永利[1] 朱佳[2] 史册[1] 尚玲玲[1] 马瑞[1] 

机构地区：[1]韩山师范学院化学系,广东潮州521041 [2]深圳职业技术学院城市水良性循环工程研发中心,广东深圳518055

出　　处：《环境科学研究》2013年第5期561-568,共8页Research of Environmental Sciences

基　　金：广东省高等学校人才引进专项资金(2011116);国家环境保护公益性行业科研专项(201209009);潮州市科技计划项目(2008S20)

摘　　要：采用煅烧、酸浸的方法对高岭土进行改性,通过对SEM、XRD、FT-IR、EDS、孔结构表征及高岭土对Cr(Ⅵ)的去除能力研究,确定高岭土的改性条件,考察改性高岭土对Cr(Ⅵ)的吸附特性.结果表明:①高岭土的改性适宜条件为煅烧温度800℃、煅烧时间3 h、c(HCl)为4 mol/L;煅烧使高岭土的结构发生变化,活性增强;酸改使高岭土孔隙通畅,吸附性能增强.②改性高岭土吸附Cr(Ⅵ)的优化条件为粒度0.15 mm、用量10 g/L、吸附温度30℃、吸附时间15 min,该条件下ρ〔Cr(Ⅵ)〕为100 mg/L时废水中Cr(Ⅵ)的去除率可达91.4%.③高岭土对Cr(Ⅵ)的吸附过程符合准二级吸附动力学模型,相比于Freundlich方程,其吸附等温式更符合Langmuir方程.Kaolin was modified with the methods of calcination and acid leaching. The modification conditions of kaolin were determined by SEM, XRD, FT-IR, EDS characterization, pore structure analysis and Cr （VI） removal on kaolin. Adsorption characteristics of modified kaolin on Cr（VI） were examined, and the experimental data were further fitted and analyzed. The resuhs showed that： 1） The appropriate conditions of modifying kaolin were under the conditions with temperature of 800 ℃ , time of 3 h, and c（HCI） of 4 mol/L. Kaolin was changed by the calcination through increasing activity, obstructing pore and enhancing adsorption performance. 2 ） The optimal conditions of modification kaolin on adopting Cr（ VI ） included particle size of 0. 15 ram, dosage of 10 g/L, adsorption temperature of 30 ℃, adsorption time of 15 rain. Under this condition, the removal rate could reach 91.4% in the wastewater of concentration of Cr（VI） 100 mg/L. 3） Kaolin adsorption process on Cr（ VI ） could be addressed by the dynamic model of Pseudo-second Order. The adsorption isotherm was more suitable to Langmuir equation compared with Freundlich equation.

关 键 词：高岭土 改性 Cr(Ⅵ) 吸附特性 吸附动力学 吸附等温线 稳定性 

分 类 号：X703.5[环境科学与工程—环境工程]