A STUDY OF THE REMOVAL OF CU (II) FROM AQUEOUS SOLUTION BY SORPTION ON ZEOLITE A

The objective of this study is to present the results of removal of copper by the method of sorption on zeolite A. The batch experiments were conducted for both the kinetics for the sorption isotherms. The experimental variables studied were pH, contact time at different initial concentrations, the amount of sorbent, temperature and stirring speed. The sorption capacity depends on the pH and mass of sorbent, but the temperature and stirring rate showed no influence. Several mechanisms of retention of copper on the zeolite could be competitive (ion exchange, complexation or precipitation and sorption). The modeling of experimental data on kinetics showed that the model of pseudo-second order describes satisfactorily the sorption on the zeolite, and that the limiting step of the speed distribution intraparticle. Statistical analysis of the constants for Langmuir-Freundlich equation has shown that this model seems most appropriate to describe this phenomenon of sorption, which indicates the heterogeneity of the surface sorption of the zeolite.