A kind of SIO2 modified low-carbon alkane dehydrogenation catalyst and preparation method thereof

Abstract

The invention discloses a SiO2 modified low carbon alkane dehydrogenation catalyst and a preparation method thereof. The external surface of the catalyst is a SiO2 coating, active Al2O3 is adopted as a carrier, chromium is adopted as an active component, one or more of K, Fe, Co, Ni, Zr, Ce, Cu, Zn, La and Ga is / are adopted as an assistant, and the catalyst comprises the SiO2 coating accounting for 0.05-1.0% of the weight of the carrier, the Cr2O3 accounting for 3.0-30.0% of the weight of the carrier, assistant metal(s) oxide accounting for 0.1-8.0% of the weight of the carrier, and the balance of alumina. The preparation method comprises the following steps: 1, loading the active component Cr to the active Al2O3 carrier, drying the active Al2O3 carrier loaded with Cr, and roasting the dried active Al2O3 carrier loaded with Cr; 2, carrying out saturated impregnation on the obtained roasted product in an impregnating solution containing assistant meta, and carrying out semidrying dehydration; 3, impregnating a catalyst precursor in an organic solvent solution containing estersil; and 4, drying the catalyst precursor, and roasting the dried catalyst precursor to obtain the catalyst. The catalyst has high mechanical strength and high wear resistance, and has good alkane conversion rate and good olefin selectivity in a low-carbon alkane dehydrogenation reaction.

Description

technical field [0001] The present invention relates to a SiO 2 A modified low-carbon alkane dehydrogenation catalyst and a preparation method thereof. Background technique [0002] The development of shale gas in North America has led to a sharp decline in natural gas prices relative to crude oil prices, while the production of large condensate liquids (NGLs) in shale gas has also increased rapidly. Shale gas condensate is rich in low-carbon alkanes such as ethane, propane, and butane. Ethane can be used as a cracking raw material to produce ethylene. Therefore, FCC technology alone cannot meet the rapidly growing demand for propylene. Dehydrogenation of low-carbon alkanes in natural gas (conventional natural gas, shale gas, coalbed methane, combustible ice, etc.) to produce low-carbon olefins is an effective way to solve this problem. Moreover, with the increasing scarcity of petroleum resources, the production of propylene has changed from relying solely on petroleum as...

AI Technical Summary

Problems solved by technology

For mesoporous materials such as alumina, the pore size is larger, and silicon ester molecules can enter the pores of alumina, and the SiO remaining in the pores after calcination 2 It not only changes the internal structure of the pores, but also affects the loaded main catalytic components, and even blocks the secondary pores, so that the active components in the secondary pores cannot contact the reactants to carry out the catalytic reaction.

Images