摘要
以工业废弃物锯末为吸附剂,研究其对水中Cu2+的吸附特性.结果表明,锯末对Cu2+的吸附速度较快,1 h后基本达到平衡.准二级速率方程很好地模拟了吸附反应的动力学方程(R2>0.99).锯末对Cu2+吸附主要机制是离子交换,吸附量随pH升高而升高.离子强度对吸附反应有一定影响:Cu2+和锯末一部分是内层结合,一部分是外层结合.经过酸碱处理的锯末在吸附能力上有了一定程度的提高.Langmuir模型对原始锯末的吸附等温线拟合最好,Langmuir-Freundlich模型对经过酸碱处理的锯末拟合最好.热力学分析显示吸附反应具有自发性、放热、熵增特性.
Sawdust was used to remove the copper ion from water as an absorbent.The result showed that adsorption of Cu^2＋ on the sawdust was a very rapid process and arrived at equilibrium about 1 h.The pseudo-second order kinetic equation gave better fitting result（R^2〉0.99）.The main mechanism of adsorption of Cu^2＋ on the sawdust was ion exchange,and the adsorption capacity increased as pH increased.Ion strength had some effects on adsorption capacity： one part of Cu^2＋ was held in an inner-sphere complex and the other part of Cu^2＋ was held in an outer-sphere complex.Adsorption capacity of treated sawdust by acid and base increased compared to original sawdust.Isotherm of treated sawdust was fitted well by Langmuir-Freundlich model;original sawdust was fitted well by Langmuir model.Thermodynamics analysis showed that the adsorption process was spontaneous,exothermic and the entropy increased.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2010年第1期217-222,共6页
Environmental Science
基金
"十一五"国家科技支撑计划项目(2006BAJ08B10)
苏州科技学院院科研基金项目(Z1336)
