Natural Template Mediated Sustainable Synthesis of Nanocrystalline Zeolite with Significantly Improved Catalytic Activity

摘要

A novel, natural template mediated, one-step, direct synthesis route was developed for the preparation of nanocrystalline zeolites. Bio-template (pollen grains and yeast) was used along with a microporous zeolite structure director to obtain nanocrystalline ZSM-5. Nanocrystalline ZSM-5 exhibited large surface area, pore volume and intercrystalline mesopores when compared to the conventional ZSM-5. Bio-template (containing different functional groups) cooperatively participated in the zeolite crystallization process with the assistance of microporous zeolite structure director to form nanocrystalline ZSM-5 framework, while the cell walls of the bio-templates exerted an influence on restraining the growth of zeolite nanoparticles. Bio-template mediated synthesis strategy of the present investigation was extended for the preparation of other related materials such as silicalite, zirconosilicate, and titanosilicate. Nanocrystalline ZSM-5 and metallosilicates exhibited excellent catalytic activities involving large organic molecules, which are important for the synthesis of a wide range of industrially important fine chemicals.