Acta Phys. -Chim. Sin. ›› 2017, Vol. 33 ›› Issue (10): 1998-2003.doi: 10.3866/PKU.WHXB201705181

• ARTICLE • Previous Articles     Next Articles

An Approach to Estimate the Activation Energy of Cation Exchange Adsorption

Yan-Ting LI1,Xin-Min LIU1,*(),Rui TIAN1,Wu-Quan DING1,Wei-Ning XIU2,Ling-Ling TANG1,Jing ZHANG1,Hang LI1   

  1. 1 Chongqing Key Laboratory of Soil Multi-Scale Interfacial Process, College of Resources and Environment, Southwest University, Chongqing 400715, P. R. China
    2 Institute of Agricultural Engineering, Chongqing Academy of Agricultural Sciences, Chongqing 401329, P. R. China
  • Received:2016-12-29 Published:2017-07-17
  • Contact: Xin-Min LIU E-mail:lucimir@163.com
  • Supported by:
    the National Natural Science Foundation of China(41530855);the National Natural Science Foundation of China(41501240);the National Natural Science Foundation of China(41501241);Natural Science Foundation Project of CQ CSTC, China(cstc2015jcyjA80015);Young Talent Project of China Association for Science and Technology(2015-2017);Undergraduate Innovation Fund of Southwest University, China(20152402009);"Guangjiong" Projects of Southwest University, China(2016005)

Abstract:

Ion exchange adsorption is an important physicochemical process at solid/liquid interfaces. In this study, an approach was established to estimate the activation energy of cation exchange reaction on the charged surface, considering Hofmeister effects. The experimental results showed that Hofmeister effects strongly affect the ionic adsorption equilibrium on the charged particle surface. The position of the adsorbed counterion in the diffuse layer was predicted according to the established model, and the ion exchange activation energies for different bivalent cations were estimated via the cation exchange experiments. The activation energy decreases with increasing ion concentration, and the adsorption saturation of cations is a function of the activation energy at different concentrations. The established model of cation exchange adsorption in the present study has universal applicability in solid/liquid interface reactions.

Key words: Specific ion effect, Ion adsorption, Charged surface, Activation energy