Method for increasing utilization value of mixed C4

Abstract

The invention relates to a method for increasing the utilization value of mixed C4. The method comprises the following steps: cracking C4, carrying out selective hydrogenation for removal of alkynes and allowing vinylacetylene and 1-butyne to produce 1,3-butadiene and 1-butylene through hydrogenation, wherein the content of alkynes in hydrogenation products is less than 15*10<-9>; subjecting obtained materials to extraction and rectification so as to allow 1,3-butadiene to be separated from other C4 fractions, mixing residual C4 material flow with C4 produced in a refinery plant, subjecting obtained mixed C4 to a hydroisomerization reaction so as to allow 1-butylene in the mixed C4 to be isomerized into 2-butylene and separating isomerization products so as to obtain an isobutene product; and introducing residual C4 material flow into a disproportionation unit, allowing 2-butylene in the residual C4 material flow and ethylene to undergo disproportionation so as to produce propylene, carrying out separation and allowing unreacted ethylene and residual C4 material flow to undergo full hydrogenation so as to enable all the unsaturated hydrocarbons to undergo hydrogenation saturation. According to the method, the content of alkenes in the hydrogenation products is lower than 1%, and the products can be used as high-quality ethylene cracking materials.

Description

Technical field: [0001] The present invention relates to a process combination for comprehensive utilization of refinery C4 and cracked C4 as raw materials to produce 1,3-butadiene, isobutene, propylene, methyl ethyl ketone and ethylene cracking materials, specifically, to a process using Select combined technologies such as hydrogenation to remove alkynes, extraction, rectification, isomerization, disproportionation, and full hydrogenation to make full use of each component in refinery C4 and ethylene cracking C4, which can greatly improve A method of mixing C4 utilization values. Background technique: [0002] Mixed C4 refers to the by-product C4 fraction of the steam cracking unit and the by-product C4 fraction of the catalytic cracking unit of the refinery. The cracked C4 contains 1,3-butadiene, C4 alkanes, isobutene, n-butene, 1-butene, 2-butene, vinyl acetylene, ethyl acetylene and other components are generally extracted butadiene and isobutene is used in MTBE device...

AI Technical Summary

Problems solved by technology

[0009] CN101475429 discloses a method for comprehensively utilizing cracked C4, that is, using cracked C4 as a raw material, adopting combined technologies such as selective hydrogenation, full hydrogenation, etherification, rectification, and extraction to produce methyl tert-butyl ether, 1 -Butene, liquefied gas, 2-butene and other products, the problem is still that the butadiene component with higher added value in cracking C4 has not been effectively utilized, and the method does not involve refinery mixing Effective use of carbon four

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