Post-treatment method of titanium-silicon molecular sieve material

Abstract

The invention provides a post-treatment method of a titanium-silicon molecular sieve material. The method comprises the following steps of: adding titanium-silicon molecular sieves into an alkali aqueous solution containing a protectant, a noble metal source and a reducer, or adding titanium-silicon molecular sieves and a reducer to an alkali aqueous solution containing a protectant and a noble metal source; putting the mixture in a reaction kettle for reaction under a condition of hydrothermal treatment; and recovering the products. Compared with the prior art, when the titanium-silicon molecular sieve material treated by the method is used in the oxidizing reaction, such as the epoxidation of propylene, the conversion rate of the propylene, the selectivity of propylene oxide and the catalytic stability are obviously improved.

Description

technical field [0001] The invention relates to a post-treatment method of titanium-silicon molecular sieves, and more particularly relates to a method for treating titanium-silicon molecular sieves with compounds containing noble metals. Background technique [0002] Titanium-silicon molecular sieve is a new type of heteroatom molecular sieve developed in the early 1980s. At present, TS-1 with MFI structure, TS-2 with MEL structure, MCM-22 with MWW structure and TS-48 with larger pore structure have been synthesized. Among them, the titanium-silicon molecular sieve TS-1 developed and synthesized by the Italian company Enichem is a new type of titanium-silicon molecular sieve with excellent catalytic selective oxidation performance formed by introducing the transition metal element titanium into the molecular sieve framework with a ZSM-5 structure. TS-1 not only has the catalytic oxidation effect of titanium, but also has the shape-selective effect and excellent stability o...

AI Technical Summary

Problems solved by technology

Appl.Catal.A: Gen., 2001, 213: 163-171 reported the research of epoxidized propylene to generate propylene oxide (PO), H 2 and O 2 React in situ to generate H on the active sites of noble metals such as Pd 2 o 2 intermediate, then generated H 2 o 2 Intermediates in adjacent Ti 4+ Epoxidized propylene on the position to generate propylene oxide. Although the reaction conditions are mild and the selectivity is good, there are defects such as low catalyst activity and poor catalyst stability.