Y-SHAPED MOLECULAR SIEVE AND METHOD FOR SYNTHESIS THEREOF Russian patent published in 2024 - IPC C01B39/24 B01J29/08 B82Y30/00 

FIELD: molecular sieve synthesis technique.

SUBSTANCE: present invention relates to a Y-shaped molecular sieve and a method for synthesis thereof, in particular to a Y-shaped molecular sieve having a small particle size and a high ratio of silicon oxide to aluminum oxide, and a method for synthesis thereof. Described is a Y-shaped molecular sieve, in which the particle size of the molecular sieve is 20–100 nm, the molar ratio of silicon oxide/aluminum oxide of the molecular sieve is 4.5–7, fraction of particles of 40–70 nm in the molecular sieve, measured using a dynamic light scattering method, ranges from 80% to 95%. Also described is a method for synthesis of a Y-shaped molecular sieve, which includes the following steps: (1) mixing a silicon source, an aluminum source, an alkali source and water and performing a first crystallisation of this mixture to obtain a structure-forming agent A, in the XRD spectrogram of which a characteristic diffraction peak belonging to the Y-shaped molecular sieve is not observed; (2) adding one or more of a silicon source, an aluminum source, an alkali source and water to the structure-forming agent A and performing a second crystallisation to obtain the structure-forming agent B, which has a degree of crystallinity within range of 5%–20%; (3) adding one or more of a silicon source, an aluminum source, an alkali source and water to the structure-forming agent B and performing a third crystallisation; where molar ratio Na₂O:H₂O at step (1) is lower than molar ratio Na₂O:H₂O at step (2) by 0.01–0.045.

EFFECT: obtaining a Y-shaped molecular sieve having a high silicon oxide-aluminum oxide ratio, small particle size, uniform particle size distribution and good hydrothermal stability.

18 cl, 2 dwg, 2 tbl, 14 ex