Method for synthesizing all-silica zeolite beta with small crystal size

摘要

A method for synthesizing the all-silica zeolite beta with small crystal size is disclosed. This method comprises the steps of: (a) forming a reaction mixture comprising (1) a source of silicon dioxide (SiO2) (2) a source of fluoride ions (F-), (3) a source of tetraethylammonium cations (TEA+), and (4) water (H2O) at predetermined mole ratios of the source of silicon dioxide, the source of fluoride ions, the source of tetraethylammonium cations, and water; (b) crystallizing the reaction mixture; and (c) recovering the crystalline material formed, wherein the pH of the mixture before crystallization has a value of 6 to 9, and the pH of the mixture after crystallization has a value of 6 to 8. This improved method gives a fast and efficient way of synthesis of all-silica zeolite beta with an average crystal size of less than 5 µm.