Catalyst used for alkane catalytic dehydrogenation and preparation method thereof

Abstract

A catalyst for alkane dehydrogenation comprises a component A and a component B, wherein the component A is an oxide selected from one or more of La, Fe, Zn, Cu, Co or Ce, and the content of the component A in the catalyst accounts for 0.5 to 50 wt%, preferably 10-30 wt%; the component B is a mixed oxide or a composite oxide selected from one or more of SiO2, Al2O3, ZrO2, Ga2O3 and MgO, and the content of the component B in the catalyst accounts for 50 to 99.5 wt%, preferably 70-90 wt%. The catalyst provided by the invention has high alkane single-pass conversion and high selectivity of olefin, after repeated regeneration, the reactivity is very stable, and the catalyst is used in a circulating fluidized bed reaction device.

Description

technical field [0001] The invention relates to a dehydrogenation catalyst, in particular to an alkane dehydrogenation catalyst and a preparation method of the catalyst. Background technique [0002] With the expansion of refinery units and ethylene units, there will be more and more low-carbon alkanes to be further developed and utilized. As an effective way to rationally utilize low-value saturated alkanes to produce high-value-added corresponding alkenes, alkane dehydrogenation has attracted extensive attention of researchers in recent years. [0003] Catalytic dehydrogenation technology of alkanes has been applied industrially as early as decades ago, and there are only two kinds of catalysts used: supported noble metal Pt catalyst and Cr 2 o 3 catalyst. The use of Pt catalysts has high investment and operating costs; while Cr 2 o 3 The Cr produced by the catalyst during its preparation and use 6+ It is carcinogenic and will cause adverse effects on the human body ...

AI Technical Summary

Problems solved by technology

However, the dehydrogenation reaction of alkanes is a strong endothermic reaction. In addition to the low heat transfer efficiency of the fixed bed reactor, frequent reaction and regeneration switching operations are not good for the stability of the entire reaction system, which is likely to bring safety hazards.

UOP's Oleflex technology uses a moving bed reactor. Although the continuous operation of the dehydrogenation reaction and the coke regeneration of the catalyst has been realized, the problem of poor heat transfer efficiency has not been solved.

The only FBD-4 technology that uses a circulating fluidized bed reactor has high heat transfer efficiency and can use the heat carried by the high-temperature regenerated catalyst for the strongly endothermic dehydrogenation reaction. However, the disadvantage of this technology is that it uses Cr 2 o 3 catalyst, and the environmental problems brought by the catalyst cannot be underestimated, especially the inevitable catalyst loss phenomenon in the circulating fluidized bed reactor, which makes Cr 2 o 3 Environmental Hazards of Catalysts Even Nowhere to Hide

With this technology, in addition to continuous reaction and catalyst regeneration, a stable and high olefin yield can also be achieved. However, due to the introduction of the vulcanization medium, higher requirements are placed on the material of the device, which increases investment costs and operations. risk

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