改性柚皮对水溶液中Cr(Ⅵ)的吸附性能研究  

On the adsorption effect of Cr(Ⅵ) in the sewage via the modified pomelo peel

作　　者：向文英[1,2] 张雪[1] 李吉成[1] 

机构地区：[1]重庆大学三峡库区生态环境教育部重点实验室,重庆400045 [2]重庆大学低碳绿色建筑国际联合研究中心,重庆400045

出　　处：《安全与环境学报》2016年第2期284-288,共5页Journal of Safety and Environment

基　　金：高等学校学科创新引智计划项目(13041)

摘　　要：以柚子皮为原料,经乙醇处理,得到改性柚皮吸附剂,并将其用于对水溶液中Cr(Ⅵ)的吸附,研究了吸附剂用量、温度、水样初始p H值、Cr(Ⅵ)初始质量浓度、吸附时间等对水溶液中Cr(Ⅵ)吸附效果的影响。结果表明,各因素中p H值对改性柚皮吸附Cr(Ⅵ)的影响较大。对初始质量浓度为20 mg/L的Cr(Ⅵ)溶液,改性柚皮投加量为20 g/L、温度为25℃、水样初始p H=1时,吸附420 min后,Cr(Ⅵ)的去除率达99%以上。Freundlich吸附等温模型和二级吸附动力学模型可以很好地对改性柚皮的吸附过程进行线性拟合,决定系数R2分别为0.975 1和0.996 6。This paper is aimed at introducing our experimental innovation in preparing a modified absorbent by treating pomelo peel with ethyl alcohol and adopted what we have prepared for adsorbing Cr（ Ⅵ）. We have also made an exploration of the effects of absorbent dosage,temperature,the initial p H value,the initial concentration of Cr（ Ⅵ） and adsorption time through batch experiments. At the same time,we have also made a deep-going study on the adsorption kinetics and adsorption thermodynamics of this system,which let us find that the equilibrium data can be made to fit for the Langmuir and Freundlich models. In addition,we have also tested the Pseudofirst-order,Pseudo-second-order and Elovich models from the point of view of the adsorption of Cr（ Ⅵ） to the modified absorbent. And,then,we have chosen the best-fit model via the linear regression correlation coefficient values,which has then been named R2. Besides,it has been found that the more the R2,the better the model can be matched. The results of our study prove that the p H value is the main influential factor and the maximum adsorption rate can be detected at p H value of 1. 0,while the temperature also influences the adsorption ability. What is more,we have also found that the absorbent can be added to the solution in a proportion of its initial concentration as 20 mg / L,with the initial p H = 1 and 25 ℃ with an adsorbent dosage of 20 g / L. It is also made clear that the system has to undergo an upward trend in 420 minutes,whereas the removal rate of Cr（ Ⅵ） can be made to reach over 99%. Under the room temperature,the data of the equilibrium sorption experiments prove to be well in accord with Freundlich isotherm when compared to the Langmuir isotherm,with the related coefficient of the model being 0. 9751. Besides,we have also made a serious evaluation of the controlling principles of the adsorption process,such as the kinetic equations of the mass transfer and the chemical reaction,which let us confirm that under the adsorption temp

关 键 词：环境工程学 柚子皮粉 Cr(Ⅵ) 吸附效果 热力学 动力学 

分 类 号：X703.1[环境科学与工程—环境工程]