Preparation method of ZSM-5@t-ZrO2 core-shell catalyst

Abstract

The invention discloses a preparation method of a ZSM-5@ t-ZrO2 core-shell catalyst. The preparation method comprises the following steps: preparing a ZSM-5 precursor solution; at room temperature, according to a core-shell mass ratio of t-ZrO2 to ZSM-5 of 4:1 to 8:1, adding the t-ZrO2 powder into the ZSM-5 precursor solution prepared in the step (1), continuing stirring uniformly, then transferring to a reaction kettle, performing hydrothermal crystallization at 180 DEG C for 48h, cooling, filtering, washing by using deionized water till a neutral state, drying at 105 DEG C for 6h, and roasting at 500-600 DEG C for 3h to obtain the ZSM-5@t-ZrO2 core-shell catalyst. The catalyst prepared by the preparation method provided by the invention can simultaneously increase the methanol conversionrate and the methanthiol selectivity and has a long service life.

Description

technical field [0001] The invention belongs to the technical field of chemical industry, and specifically relates to a ZSM-5@t-ZrO 2 The preparation method of the core-shell structure catalyst. Background technique [0002] ZSM-5 molecular sieve is made of SiO 4 and AlO 4 A microporous silica-alumina molecular sieve with tetrahedral units interlaced to form a three-dimensional intersecting channel structure. Because of its rich and adjustable B-acid properties, high specific surface area and unique shape-selective function of microporous products, it is widely used in methanol catalytic cracking hydrocarbon production process, hydrogen sulfide methanol production process of methyl mercaptan, etc. However, in the hydrogen sulfide-methanol process of producing methyl mercaptan, because of its unique acid-base catalytic mechanism, the catalyst must be both acid-base and amphoteric, resulting in a poor catalytic effect of a single molecular sieve catalyst, which cannot eff...

AI Technical Summary

Problems solved by technology

However, in the hydrogen sulfide-methanol process of producing methyl mercaptan, because of its unique acid-base catalytic mechanism, the catalyst must be both acid-base and amphoteric, resulting in a poor catalytic effect of a single molecular sieve catalyst, which cannot effectively solve how to coordinate the different requirements of methanol and methyl mercaptan Dissociation Transformation and Reaction Formation Environmental Conditions Contradictions

[0003] In view of the above problems, the existing research mainly focuses on the acid-base properties of catalysts, but based on the single oxide or molecular sieve impregnation loading modification of active components and various additives, the newly generated active centers will sacrifice or cover the original catalyst. Part of the active center may even block some of the pores, resulting in an insignificant improvement in the catalytic performance of the catalyst and a short service life