Abstract:
The Cu-clinoptilolite was prepared by liquidphase ion exchange,and the corresponding value of C/Co and q/Q in the exchange liquor and clinoptilolite phase was calculated according the measured Cu
2+ concentration while reaching exchange equilibrium under different temperature and primary Cu
2+ concentration,the ion exchange isotherm was plotted according above data.Further,the corrected selectivity coefficient Kc and the exchange equilibrium constant Ka was also calculated,and the linear relation was educed between lnKα and 1/T.On the basis,enthalpy change Δ
rH
θm,Gibbs free energy Δ
rG
θm and entropy changes Δ
rS
θm were figured out.The researching results show Δ
rH
θm=7.101KJ/mol、Δ
rG
θm<0、Δ
rS
θm>0,these illustrates the ion exchange process is an endothermic and entropy increase reaction;ion exchange can occur automatically under different experimentation temperature,but increasing temperature is advantageous to Cu
2+ exchange.