Multicomponent ion exchange on clinoptilolite

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2006
Bayraktaroğlu, Kerem
Zeolites are crystalline, hydrated aluminosilicate minerals that are characterized by their ability to exchange some of their constituent cations with cations in aqueous solutions, without a major change in their crystalline structure. Clinoptilolite is the most abundant ype of zeolite and it has received extensive attention due to its favorable selectivity for mmonium and certain heavy metal cations. The aim of this study is to investigate the binary and ternary (multicomponent) ion xchange behavior of sodium form of Gördes type clinoptilolite for ammonium,cadmium and sodium ions. For this purpose, NH4 +-Na+,Cd2+-Na+ binary systems and NH4 +-Cd2+-Na+ multicomponent system were investigated both in batch and column systems at 0.1 and 0.01 constant total normality respectively and at 250C constant temperature. As a result of binary and ternary experiments, clinoptilolite’s affinity for both ions but greater affinity to NH4+ ion than Cd2+ ion was observed and the selectivity sequence of Gördes clinoptilolite was determined as NH4+>Cd2+>Na+ in binary and multicomponent batch and column operations. Additionally, total ion exchange capacities and maximum exchange levels of Gördes clinoptilolite for both ions were determined in batch systems whereas breakthrough capacities and column efficiencies (for three different flow rates) were determined in column systems. Finally, it was concluded that the increase of the flow rate reduced the breakthrough capacities and column efficiencies of Gördes clinoptilolite for ammonium and cadmium ions in multicomponent column systems involving more than one cation.

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Citation Formats
K. Bayraktaroğlu, “Multicomponent ion exchange on clinoptilolite,” M.S. - Master of Science, Middle East Technical University, 2006.