Characterization of Three Iranian Kaolinsfor Transformation to Y Zeolite

The extensive use of zeolites as catalysts and catalyst suppo rts in heteregenous cll t:tly~i ... in the che mical and petrochemical industries is well established. Kaolin is a suitable aluminosilicate mineral which in appropriate conditions can be transformed to a three dimensional zeolite structure with a high surface area. A vast and dispersed kaolin deposites in the country are high potential sources for studing synthesis of zeoli tes. The kaolins investigated in this study were from Zenoo z ~ Azarba y jan , Rokh·Scf c ed ~ Khora s an and Samirom· Esfahan. Theywere activated by ca lcination at 750°C to convert them to meta kaolin. Synthesis gel was prepared from metakaolin, sodium hydroxide, sodium silicate and sodium chloride. Synthesis was performed by hydrothermal method at 101YC. The products were examined by XRD and EDX/SEM for structural and chemical analysis. All three types kaolins were converted to zeolite Y in specific condition. Silicon to aluminum ratio in the prepared zeolite framework was in the range of 1.7·2.15 where the highest value belongs to the zeolite prepared from Samirom kaolin. ,