| abstract |
An alkali metal ion-modified titanium silicon molecular sieve for a gas phase epoxidation reaction between propylene and hydrogen peroxide, and the preparation method therefor, which relates to the field of petrochemical technology. The method of the present invention comprises: step 1, preparing a modified solution of alkali metal hydroxide; step 2, using the alkali metal hydroxide solution to perform a controlled hydrothermal treatment on a precursor of a TS-1 molecular sieve; step 3, the post-treatment of the hydrothermal-modified TS-1 molecular sieve, comprising solid-liquid separation, washing, drying and calcination; during washing, using a low concentration of the alkali metal hydroxide solution to wash a modified TS-1 molecular sieve wet material so as to retain alkali metal ions on a silanol group of a modified titanium silicon molecular sieve, the alkali metal ion modified skeletal titanium active center has an infrared feature absorption band within the range of higher than 960cm-1 and lower than 980cm-1. The prepared alkali metal ion-modified titanium silicon molecular sieve has a significant catalytic performance in the gas phase epoxidation reaction between propylene and hydrogen peroxide. |