摘要
坡缕石造粒改性、酸改性后,研究改性坡缕石吸附Pb(Ⅱ)的等温吸附特征、pH值和温度对吸附的影响、热力学特征及动力学特征.Langmuir、Freundlich等温式拟合,Langmuir拟合效果较好.在试验条件下,在pH>4时,改性坡缕石吸附Pb效果良好;且随温度的升高,吸附效果先升增强后降低,在20℃出现拐点;吸附符合准二级动力学模型;热力学分析显示,改性坡缕石吸附Pb反应为放热反应且能自发进行且为焓驱动.在温度为20℃,pH=4时,改性坡缕石吸附Pb的Qm为65.324mg/g.
After making granulation and acid modification to palygorskite,the isothermal adsorption characteristics,the influences made by pH and temperature,the thermodynamic characteristics and the dynamic characteristics for modified palygorskite have been studied in this paper.With the Langmuir and Freundlich isotherm fitting,the result of the Langmuir is better.Under the conditions of experiment,the effect of adsorption for Pb by modified Playgorskite is good in the pH>4;with temperature increasing,the effect of adsorption is increasing firstly and then decreasing,showing the inflection point at 20 ℃;the process of adsorption is in accordance with pseudo-second-order kinetic equation;the result of thermodynamic analysis shows that the adsorption process for Pb is exothermic,spontaneous and is driven by enthalpy.When the temperature is 20℃and the pH=4,the amount of Pb adsorption on the modified playgorskite is 65.324mg/g.
出处
《西南师范大学学报(自然科学版)》
CAS
CSCD
北大核心
2014年第7期157-162,共6页
Journal of Southwest China Normal University(Natural Science Edition)
基金
国家大学生创新创业训练计划(1210635022)
中央高校基本科研业务费(XDJK2013C154)
关键词
坡缕石
改性
铅
吸附
palygorskite
modified
lead
adsorption