摘要
研究了凹凸棒石对水中3,4-二氯苯胺(3,4-DCA)的吸附行为.对不同温度下(298K,303K,313K)的数据分别用Langmuir,Freundlich和Redlich-Peterson模式进行拟合.并用假一级方程和假二级方程描述凹凸棒石对3,4-DCA的吸附动力学过程.结果表明:吸附作用受pH值影响明显,在pH=4.0时,吸附量最大;凹凸棒石的吸附能力随着温度的升高而降低;Redlich-Peterson方程更适合描述3,4-DCA在凹凸棒石上的吸附行为;Gibbs自由能(ΔG0)、熵变(ΔS0)和焓变(ΔH0)值均小于零,说明此吸附过程是自发进行的、放热的物理吸附过程;假二级方程更适用于描述凹凸棒石对3,4-DCA的吸附动力学过程.
Adsorption of 3,4-dichloroaniline （3,4-DCA） onto attapulgite clay was conducted in the present article. The equilibrium data were fitted with the Langmuir, Freundlich and Redlich-Peterson models to describe the equilibrium isotherms. The kinetics rates were modeled using pseudo-first-order and pseudo-second-order kinetic equations. The results showed that adsorption of 3,4-DCA onto attapulgite clay was affected remarkably by the pH value and the maximum adsorption amount was achieved at an optimum pH of 4. 0 ; The equilibrium adsorption amount decreased with increasing temperature; The adsorption process could be depicted primely by Redlich-Peterson function; The Gibbs free energy （ △G^0 ）, enthalpy （ △H^0 ） and entropy （△S^0 ） were all below zero, which indicated the adsorption was a spontaneous and exothermic process; The kinetics data were better fitted with the pseudo-second-order kinetic model.
出处
《环境化学》
CAS
CSCD
北大核心
2009年第3期360-363,共4页
Environmental Chemistry
基金
上海同济高廷耀环保科技发展基金
南京大学优秀博士学位论文培育基金资助
