Base-modified catalyst and method for preparing ethylene through hydrogenating reaction of carbon monoxide

Abstract

The invention belongs to ethylene preparation through direct hydrogenation conversion of carbon monoxide, and particularly relates to a base-modified catalyst and a method for preparing ethylene through a hydrogenating reaction of carbon monoxide. According to the method, mixed gas of carbon monoxide and hydrogen is adopted as a reaction raw material, a conversion reaction is performed on a fixedbed or a mobile bed, and a catalyst which is a composite catalyst is obtained by compounding a component A and a component B together through mechanical mixing; and active components of the componentA are metal oxide, and the component B is an organic alkali-modified molecular sieve with an MOR structure; the weight ratio of the active components of the component A to the component B is 0.1-20, preferably 0.3-8, and the reaction process has a high product yield and selectivity; and the selectivity to C2-C3 olefin is as high as 86-92%, hydrocarbon products containing four carbon atoms or aboveare less than 7%, and the selectivity to a by-product methane is extremely low and lower than 5%; and the selectivity and space-time yield of ethylene are obviously improved, and the selectivity reaches 75-85%, and the method has a good application prospect.

Description

technical field [0001] The invention belongs to carbon monoxide hydrogenation to produce low-carbon olefin high-value chemicals, in particular to an alkali-modified catalyst and a method for carbon monoxide hydrogenation to produce ethylene. Background technique [0002] Ethylene is a very important basic chemical raw material and one of the largest chemical products in the world. The ethylene industry is the core of the petrochemical industry and occupies an important position in the national economy. Low-carbon olefins refer to olefins with carbon atoms less than or equal to 4. Low-carbon olefins represented by ethylene and propylene are very important basic organic chemical raw materials. With the rapid growth of my country's economy, my country's ethylene industry has developed rapidly and occupies an important position in the world's ethylene market. For a long time, the low-carbon olefins market has been in short supply. At present, the production of ethylene mainly ...

AI Technical Summary

Problems solved by technology

But ethylene single selectivity is less than 20%

Bao Xinhe and Pan Xiulian's team at Dalian Institute of Chemical Physics, Chinese Academy of Sciences reported that ZnCr supported on alumina 2 o 4 Oxide and hierarchical porous SAPO-34 molecular sieve composite bifunctional catalyst (Jiao et al., Science351 (2016) 1065-1068), achieved a selectivity of 80% for low-carbon olefins at a CO conversion rate of 17%, but ethylene Selectivity below 30%

In the patent 201610600945.6 they applied for, a bifunctional catalyst containing oxygen holes and MOR molecular sieves was used for the one-step olefin reaction of syngas, which increased the selectivity of ethylene to 30-75%, but the number of carbon atoms in the by-product exceeded 3 has more hydrocarbons, which affects the application of this technology

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