Abstract: Surface coatings developed in the Nanhu Lake(Changchun) were used to study the characteristics of thermodynamics and kinetics of Co, Ni, and Cu adsorption to them. Statistical analysis of the adsorption data show that the thermodynamic data of each metal fit the Langmuir isotherms. At low ion concentrations(<0.5 μmol/L), the adsorption capacity of these metals to the surface coatings decreased in the order Co, Cu, and Ni, while at high ion concentrations(>0.5 μmol/L), the capacity decreased in the order Cu, Co, and Ni. The kinetic data indicate that the adsorption reached equilibrium in several hours. Four kinetic models, i.e., Elovich equation, double-constant rate equation, first-order kinetics equation and Langmuir kinetics equation, can all be used to describe the adsorption process, especially the Langmuir kinetics equation.

Key words: Surface coating, Adsorption, Co, Ni, Cu