Influence of Synthesis Conditions on Chabazite Zeolite Crystallization in LiOH Solution

The chabazite zeolite of potential practical importance has been obtained based on the natural mineral of Nakhchivan Autonomous Republic. Chabazite has a wide range of application and therefore its optimal synthesis conditions have been determined. The chabazite zeolite of potential practical importance has been obtained based on the natural mineral of Nakhchivan. The hydrothermal synthesis has been carried out in Morey type autoclaves made up of 45MNFT stainless steel with a volume of 20 cm3, and with the filling coefficient of F = 0.8. The hydrothermal crystallization experiments have been carried out generating a temperature gradient Т = 0 and without stirring of the reaction mass. The optimal conditions established in this study for the synthesis of chabazite zeolite with a 100 % degree of crystallinity are as follows: temperature of 100°C, alkaline solution of 10-20% LiOH and processing time of 50 hours. It was shown that at temperature below 100°C mordenite+chabazite+quartz is present in the reaction products, and at temperature above 100°C, chabazite+clinoptilolite+albite, chabazite+clinoptilolite+cristobalite, chabazite+clinoptilolite were obtained. At a concentration of LiOH below 10%, mordenite+quartz+chabazite are present in crystallization products, and at a concentration of LiOH above 20%, clinoptilolite+chabazite, hydrosodalite+albite+cristobalite have been obtained. Moreover, when processing time is below 50 hours, mordenite+quartz+chabazite crystallizes, and when processing time is over 50 hours, we obtain clinoptilolite+chabazite+cristobalite, hydrosodalite+albite was obtained. The initial sample and the product obtained were studied by X-ray diffraction (2D PHASER “Bruker” (CuKα, 2θ = 20–80°)), thermogravimetric (NETZSCH STA 449F3 STA449F3A-0757-M) and scanning electron microscopy (Hitachi TM-3000).