摘要
为提高凹凸棒对水中As(Ⅲ)的吸附能力,以七水合氯化镧、凹凸棒土(ATP)为原料,通过浸渍法制得载镧改性凹凸棒土。通过响应面优化试验,探究了最佳改性条件,并进行了改性材料对水中As(Ⅲ)的等温热力学和吸附动力学试验。结果表明:改性时氯化镧的最佳浓度为0.6 mol/L,吸附剂最佳投加量为0.3 g,最佳反应pH值为6;通过响应面优化试验,得到最佳改性条件为:氯化镧浓度为0.61 mol/L、pH值为6.8和吸附剂投加量为0.38 g,此时载镧改性凹凸棒土对As(Ⅲ)的吸附量为166μg/g;吸附等温线符合Freundlich方程模型,吸附过程为自发且吸热过程,准二级模型能更准确地描述其吸附动力学过程,表明该吸附过程中化学吸附起主要作用。
In order to improve the adsorption capacity of attapulgite(ATP)to As(Ⅲ)in water,lanthanum chloride heptahydrate and ATP were used to prepare lanthanum modified attapulgite(La-ATP)by impregnation method.Through response surface optimization test,the optimal modification conditions were explored,and the isothermal thermodynamics and adsorption kinetics of As(Ⅲ)in water were tested.The results show that the optimal concentration of lanthanum chloride is 0.6 mol/L,the optimal dosage of adsorbent is 0.3 g,and the optimal reaction pH value is 6.Through the response surface optimization test,the optimal modification conditions are as follows:the concentration of lanthanum chloride is 0.61 mol/L,pH value is 6.8 and the dosage of adsorbent is 0.38 g.At this time,the adsorption capacity of La-ATP to As(Ⅲ)is 166μg/g.The adsorption isotherm is in accordance with Freundlich equation,and the adsorption process is spontaneous and endothermic.The quasi second-order model can more accurately describe the adsorption kinetic process,indicating that the chemical adsorption plays a major role in the adsorption process.
作者
邓天天
李晗晟
徐赵高龙
丁明慧
刘千源
DENG Tiantian;LI Hansheng;XU Zhaogaolong;DING Minghui;LIU Qianyuan(School of Resources and Environment,Henan University of Engineering,Zhengzhou 451191,China)
出处
《水资源保护》
CAS
CSCD
北大核心
2020年第5期104-112,共9页
Water Resources Protection
基金
河南省科技攻关项目(192102310505)
河南省高校省级大学生创新创业训练计划项目(S201911517004)。
关键词
凹凸棒土
响应面优化试验
镧
吸附特性
As(Ⅲ)
水环境
attapulgite
response surface optimization test
lanthanum
adsorption property
As(Ⅲ)
water environment
