PREPARATION OF ZEOLITE ZSM-5 GRANULATES FREE FROM INORGANIC BINDERS

摘要

The invention of the preparation of zeolite ZSM-5 granulates free from inorganic binder provides a synthetic process for the preparation of highly crystalline zeolite granulates without using inorganic binder from amorphous sodium aluminosilicate granules. This invention falls within the scope of the inorganic chemical technology. Granules were prepared from the powdered dried amorphous sodium aluminosilicate gel without containing organic structure directing agent. The proposed synthesis process provides the preparation of the amorphous sodium aluminosilicate gel from sodium water-glass, sodium aluminate using less than 5% of zeolite ZSM-5 seed crystals. The pH value of the gel is adjusted using dilute sulfuric (VI) acid. Dried amorphous sodium aluminosilicate gel is granulated using sodium water-glass. Thermally treated amorphous sodium aluminosilicate granulate is transformed in the alkaline solution into crystalline zeolite ZSM-5 granulate by the hydrothermal synthesis from 22 to 28 hours at a temperature from 170 to 190°C.