钢渣对水溶液中砷的吸附动力学和热力学特性试验  

Experiment of Characteristics of Adsorption Kinetics and Thermodynamics for Arsenic( As)Removal by Steel Slag

作　　者：杨长明[1] 陈氏秋张 沈烁[1] 

机构地区：[1]同济大学环境科学与工程学院长江水环境教育部重点实验室,上海200092

出　　处：《净水技术》2015年第2期83-89,共7页Water Purification Technology

基　　金："十二五"国家水体污染控制与治理科技重大专项(2011ZX07316-002)

摘　　要：以炼钢厂固体废弃物钢渣为材料，通过批量平衡吸附法，并结合宏观热力学和动力模型应用，分析和研究了钢渣对水溶As（III）的吸附特征。结果表明钢渣在吸附As（III）过程中，初始阶段吸附量迅速增加，随着浓度的增加，吸附逐渐趋于饱和，最后达到平衡，具有“快速吸附、缓慢平衡”的特点。钢渣吸附材料具有极高的最大吸附容量，高达3．58×10^4mg／kg。钢渣对As（III）的吸附均符合Langmuir和Freundlich吸附等温线，其中钢渣对As（III）的吸附特征与Freundlich等温吸附方程吻合性最好，相关系数（R^2）达到0．99以上。钢渣对As（III）的吸附动力学数据均符合一级动力学方程、Elovich方程和双常数方程，拟合优度用相关系数（R^2）为0．92～0．98，相比较而言，钢渣对As（III）的吸附以Elovich方程为最佳模型。The steel slag which is regarded as solid waste from an iron and steel plant was selected as adsorbent. The adsorption capability and dynamic characteristics was investigated and evaluated by batch equilibrium adsorption method combined with thermodynamics and kinetics model. The results show that adsorption capacity increases rapidly in initial phase of the process of As （III） adsorption; then adsorption tends gradually to be saturated with the increase of concentration, and finally achieves a balance. The adsorption process can be characterized by rapid absorption and slow balance. The steel slag has a high maximum adsorption capacity, which is 3.58 × 10^4mg/kg. Adsorption process of As （III） by steel slag well fits Langmuir and Freundlich adsorption isotherm model. By comparison, As （III） adsorption dynamics is better identical with Freundlich model （R^2 〉 0.99）. As （III） adsorption by steel slag kinetics data are in line with the first-order kinetics equation, Elovicb equation and double constant equation, and R^2 is from 0.92 to 0.98. Of all the three equations, Elovich equation is most suitable for fitting the kinetic process of As （III） adsorption.

关 键 词：钢渣 三价砷去除 吸附动力学 热力学过程 

分 类 号：X131[环境科学与工程—环境科学]