Effects of silicon-aluminum ratio and water-heat ratio on SAPO-34 molecular sieve
In the hydrothermal synthesis of SAPO-34 molecular sieves, SiO2 / Al2O3, H2O / Al2O3, and the crystallization temperature have a significant effect on the synthesis of SAPO-34 molecular sieves.Relative crystallinity, particle size distribution, and average particle size have important effects.
① When 0.4 ≤ SiO2 / Al2O3 ≤ 0.8, the relative crystallinity of the product followsAs the silicon content increased, it increased to 100%. The particle size distribution gradually narrowed and became uniform, and the average particle size also decreased to 7.5 μm. whenSiOWhen 2 / Al2O3> 0.8, the relative crystallinity of the product decreases with the increase of the amount of silicon source, and the average particle size increases and the distribution is uneven.
② whenWhen 60≤H2O / Al2O3≤80, the relative crystallinity of the product decreases with increasing water content, and the average particle size also increases and the particle size distributionBecomes uneven.
③ As the crystallization temperature increases from 160 ° C to 200 ° C, the relative crystallinity of the product increases to 100%, and the average particle size varies withThe increase. When the crystallization temperature is 160 ° C, although the product grain size is the smallest, the relative crystallinity of the product is the lowest and the particle size distribution is at this time.Wide and unevenEffects of silicon-aluminum ratio and water-heat ratio on SAPO-34 molecular sieve
