Adsorption kinetics and thermodynamics of Cu2+ on a new type of attapulgite, which was treated with procedures of freeze-drying and heating(change temperature treating) was studied. The experimental results indicated that the adsorption processes conformed to pseudo-second order equation at 298 K. In the temperature range of 298 ~ 318 K, the adsorption isotherms followed the Langmuir isothermal equation more exactly, and the maximum adsorption quantity was in the range of 54.64~71.94 mg/g. According to the measured thermodynamic parameters, the adsorption enthalpy, the Gibbs free energy and the entropy could be calculated, and they were 60.46 kJ/mol, -21.32~26.82 kJ/mol and 273.77 J/(molK), respectively. These results indicated that the adsorption of Cu2+ on the treated attapulgite was spontaneous and endothermic, and the adsorption was mainly dominated by chemical adsorption.%通过吸附实验,研究了经冷冻干燥-加热处理(变温处理)的凹凸棒石黏土对Cu2+的吸附动力学和热力学特性.结果表明,在298K下,变温处理后的凹凸棒石黏土吸附Cu2+符合拟二级动力学方程.当温度在298～318K之间时,吸附等温线更好地符合Langmuir方程,饱和吸附量为54.64～71.94 mg/g.热力学计算表明,摩尔吉布斯自由能变为-21.32～-26.82 kJ/mol,摩尔焓变为60.46 kJ/mol,摩尔熵变为273.77 J/(mol·K),表明变温处理后凹凸棒石黏土对Cu2+的吸附是自发吸热过程,以化学吸附为主.
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