Patent ID: 7601330
Filing Date: 2009-10-13
Classification: C01B

Abstract:
1. A process for producing a binder-free homogeneously crystallized and shaped ZSM-5 zeolite crystals comprising: mixing, by a one-off way, diatomite or carbon white as a silica source, oxides of aluminum, aluminium salts or aluminates as an aluminum source, a seed crystal orienting agent, and an extrusion aid together with a silica sol or water glass in a desired amount for kneading and shaping to obtain the precursor mixture having a weight ratio of XNa then converting to binder-free ZSM-5 shaped zeolites with a crystal size of less than 1 μm by vapor-solid phase crystallization with organic amine and water vapor, wherein the crystallization is conducted at 120-200° C. for 48-240 hours, said seed crystal orienting agent being obtained by aging the mixture having a molar ratio of (TPA) wherein the organic amine is selected at least one from the group consisting of ethylamine, n-propylamine, n-butylamine, ethylenediamine, triethylamine and hexanediamine; and wherein the extrusion aid is at least one selected from the group consisting of sesbania powder, starch, activated carbon, polyethylene glycol, polyacrylamide and polyvinyl alcohol, and is in an amount of 0.1-4 wt % of the precursor mixture.