Ion exchange of some heavy metal ions from polar organicsolvents into zeolite Original Research Article

In the present study the possibility of ion exchange of heavy metal ions using polar organic solvents and naturalzeolite clinoptilolite is approached. The organic solvents used are nearly pure ethanol and acetone. These solventsare compared to deionized water. The heavy metal ions studied are Cu2+, Cr3+ and Fe3+. While ion exchange levelsin water are much greater for Fe3+ (53.1%) in comparison to ethanol (12.5%) and acetone (3.1%), Cr3+ is exchangedin satisfactory levels in ethanol (46.8 and 27.4% respectively) and Cu2+ in acetone (23.8 and 26.6% respectively).Infrared (IR) and ultraviolet/visible (UV-Vis) spectrometry showed that complexes are formed, which are differentin each solvent. It is concluded that the cation-solvent complex strength and charge, the possible rejection ofloosely attached solvent molecules, the formation of precipitates, the properties of the solvent and free cations andthe diameter of zeolite pore openings are all affecting the uptake of metals. Finally, the ion exchange of metalsusing zeolites is possible to take place in polar organic solvents and one significant finding is that selectivity can betotally changed.