Acta Phys. -Chim. Sin. ›› 2013, Vol. 29 ›› Issue (09): 2019-2026.doi: 10.3866/PKU.WHXB201306271

• CATALYSIS AND SURFACE SCIENCE • Previous Articles     Next Articles

Adsorption of Co(Ⅱ) and Ni(Ⅱ) on Beishan Granite:Surface Complexation Model and Linear Free Energy Relationship

CHEN Zong-Yuan1, ZHANG Rui1, YANG Xing-Long1, WU Wang-Suo1, GUO Zhi-Jun1, LIU Chun-Li2   

  1. 1 School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000, P. R. China;
    2 Beijing National Laboratory for Molecular Sciences, Radiochemistry & Radiation Chemistry Key Laboratory for Fundamental Science, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China
  • Received:2013-03-29 Revised:2013-03-29 Published:2013-08-28
  • Contact: GUO Zhi-Jun, LIU Chun-Li E-mail:guozhj@lzu.edu.cn;liucl@pku.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (91226113, 11075006, 91026010) and Special Foundation for High Level Waste Disposal, China ([2012]494, [2007]840, [2012]851).

Abstract:

The adsorption of Co(Ⅱ) and Ni(Ⅱ) on crushed Beishan granite (BS03, 600 m) was studied by a batch experimental method. The distribution coefficient (Kd) was found to vary as a function of the pH, ionic strength, and the initial concentrations of Co(Ⅱ) and Ni(Ⅱ). In the low pH range, the Kd values of Co(Ⅱ) and Ni(Ⅱ) decreased significantly as the ionic strength increased, whereas the effect of the ionic strength was weak in the high pH range. The adsorption of Co(Ⅱ) and Ni(Ⅱ) on granite was quantitatively interpreted by a model with one cation exchange reaction and two inner-sphere surface complexation reactions. A linear free energy relationship (LFER) between the equilibrium constants (K) of the surface complexation reactions and the hydrolysis stability constants of the divalent transition metals (OHK) was established. Predictions based on the LFER are in good agreement with the experimental results for the adsorption of Pb(Ⅱ) and Cu(Ⅱ) on granite.

Key words: Beishan granite, Adsorption, Co(Ⅱ), Ni(Ⅱ), Surface complexation model, Linear free energy relationship

MSC2000: 

  • O647.32