Patent ID: 7361328

Claim:
A method of preparing ZSM-5, comprising the following steps of: mixing a silica source, an alkali metal oxide source, an alumina source and water, to prepare a reaction mixture having a molar composition of M 2 O/SiO 2 (M: alkali metal ion) of 0.07-0.14, H 2 O/SiO 2 of 15-42 and SiO 2 /Al 2 O 3 of 20-100; maintaining the reaction mixture at 180-210° C. for a reaction time controlled in a range of 2-20 hours according to an intended crystal size and a particle size distribution of the ZSM-5, to obtain a nucleated reaction mixture; and maintaining the nucleated reaction mixture at 130-170° C. for 10-200 hours to form crystals of the ZSM-5.