Ion exchange with cobalt and nickel ions of Western Anatolia clinoptilolite at sodium and ammonium forms and thermodynamic analysis

Zeolites are being used commonly in chemical industries because of theircatalyst, adsorbent and ion exchange properties. In this study, the use ofnatural zeolite, Western Anatolian Clinoptilolite, which is found mostly in ourcountry was examined as an ion exchanger in sodium and ammonium forms toremove cobalt and nickel ions with ion-exchange method.In this study, as a first step chemical and XRF analysis of original clinoptilolitewere made and X-Ray-Diffraction analysis were obtained. After this,clinoptilolite was transformed into sodium form by treatment with sodiumcholoride solution. The chemical and XRF analysis of clinoptilolite is in sodiumform were made and it was examined that large amount of sodium ion wastransfered to the structure. Secondly, ion exchange equilibrium experimentswere made at 250C with 0,1 N cobalt and nickel solutions. As a result ofequilibrium experiments, the selectivity of clinoptilolite was determined as Na+> Co+2 > Ni+2In this study; clinoptilolite was converted to ammonium form by treatment withammonium chloride solution in order to see the effect of cationic form ofclinoptilolite to selectivity and chemical analysis of clinoptilolite was made.Then, ion exchange equilibrium experiments were made. At the end ofviequilibrium experiments, it was seen that sodium ion was exchanged with cobaltand nickel ions easier than ammonium ion. Finally, thermodynamicequilibrium constant (Ka ) and free energy change (∆G°) were calculated at25ºC for Co+2/ Na+- clinoptilolite and Ni+2/ Na+- clinoptilolite systems Ka and∆G° were determined as (2,92x10-3), (7,23kJ/ eguilavent) respectively for cobaltand (9,93x10-4), (8,56 kJ/eşdeğer) respectively for nickel.Science Code:912Page Number:100Keywords:Clinoptilolite, Ion Exchange, Cobalt, Nickel, Heavy MetalAdviser: Prof. Dr. Müjgan Çulfazvii