Özet:

In this study, Clinoptilolite-rich zeolitic tuff was treated with acids such as HCl, HNO3, H2SO4, and H3PO4. The effect of periods of time (3 hours and 6 hours), concentration (1 M, 2 M, 3 M, 5 M, and 10 M) and acid type  were taken as parameters. In the characterization of the zeolites, XRD, ICP-AES, FTIR, and SEM techniques were used. As the acid concentration and the treatment time were increased, the aluminum and cation removal from the structure was increased. HCl and HNO3 were more effective acids for the dealumination than H2SO4 and H3PO4. It was found out that considerable change in the texture of the zeolitic tuff didn’t take place during the H3PO4 treatment. On the other hands, acid treatment resulted in an increase in the micropore surface area and volume of the zeolite. Specific surface area of the zeolitic tuff (19 m2/g) was increased up to 213 m2/g, 236 m2/g, 202 m2/g, 118 m2/g with HCl, HNO3, H2SO4, and H3PO4 treatments, respectively. In the cases of HCl and HNO3, an increase in their concentration furthermore than 5 M caused to the collapse of the structure.

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