Development of LTA zeolite membrane from clay by sonication assisted method at room temperature for H2-CO2 and CO2-CH4 separation.

In this work, sodium aluminosilicate zeolite powder and membranes were synthesized by ultrasonic irradiation at room temperature using montmorillonite clay as precursor material. For comparison, same zeolite powder and membranes were synthesized at 100 °C also. The synthesized zeolites were characterized by X-ray diffraction (XRD), infrared (IR) spectral analysis, and field-emission scanning electron microscopy (FESEM). XRD and IR results showed that phase pure mainly LTA phase was formed after 15 days of aging at room temperature. By using the zeolite powders as seeds, membranes were synthesized on clay alumina support tubes at room temperature and also at 100 °C. In both the cases membranes were formed on support surface. The membrane thickness was found to be 15 μm. The performances of the membranes were evaluated by single gas as well as mixture gas permeation measurement for H2-CO2 and CO2-CH4 respectively. The H2-CO2 and CO2-CH4 separation selectivity for the mixture gas of the membrane was found to 16.2 and 20.9 at room temperature respectively. To the best of our knowledge, there is no report of synthesis of zeolite membrane at room temperature using clay as raw materials. For the first time we have reported the synthesis of alumino-silicate zeolite membrane on clay alumina support surface using clay as starting material by sonochemical method at room temperature.