Liquid–Liquid Microdispersion Method for the Synthesis of TS-1 Free of Extra-Framework Ti Species

Abstract

A novel liquid–liquid microdispersion method for the synthesis of TS-1 has been developed by continuous preparation of the precursor. In the novel process, the solution of TBOT in n-hexane could be very uniformly dispersed into the oligomeric silicate prehydrolysis mixture to form microdroplets by a microsieve pore reactor. Due to the fast mixing and very high mass transfer performance of the microdispersion process, the Ti species could be uniformly distributed into the mixture and were more likely to condense into the oligomeric silicate precursor species rather than appear with self-condensation. The prepared samples had a minimum molar ratio of Si/Ti at 51 without extra-framework Ti species. Furthermore, the solvent of n-hexane can be recycled by simple phase separation rather than evaporation under the conditions of using isopropanol, which reduced energy consumption. This continuous microdispersion technology could be controllable and a reliable scaling-up for the preparation of TS-1.