ADSORPTION BEHAVIOR OF Pb(II), Zn(II), Cd(II) AND Cr(VI) BY MODIFIED ZEOLITE AND BENTONITE

摘要

The batch experiments were conducted to formulate the influence of pH, adsorption time, and adsorbents dosage on adsorption capacity for Pb(II), Zn(II), Cd(II) and Cr(VI) using modified zeolite and bentonite. Under the same conditions of adsorption time, initial concentration, temperature and dosage, the results of this research indicate that ideal adsorption effect can be obtained on zeolite and bentonite for Pb(II), Zn(II) and Cd(II), which are significantly better than Cr(VI). The adsorption capacity of modified adsorbents strongly depends on pH of solution. The maximum optimum range of adsorption time could be chosen at 3?5 h and 3?7 h for zeolite and bentonite, respectively. The research also demonstrates that the adsorption form may be mainly surface complex and ions exchange.