A titanium silicalite molecular sieve and its synthesis.

摘要

The present invention relates to a titanium silicalite molecular sieve, wherein the crystal grain of the titanium silicalite molecular sieve has a ratio of (surface Si/ Ti ratio):(bulk Si/Ti ratio) being larger than 1.1 and less than 5, as wellastoa process for synthesizing a titanium silicalite molecular sieve, comprising the following steps of (1) a titanium source, a template agent, an organic silicon source, water and an optional inorganic amine souree are mixed and subjected to hydrolyzation and removing alcohols; (2) the product obtained in the step (1) is aged at 15-50°C; (3) the aged product obtained in the step (2) and asolid silicon souree are mixed homogeneously, then subjected to crystallization in a close reaction vessel, and the titanium silicalite molecular sieve is collected.