Technology for preparing heavy alkyl benzene through dehydrogenation of heavy liquid wax and alkylation of heavy olefin

Abstract

The invention discloses a complete process technology for preparing heavy alkyl benzene by using heavy liquid wax as a raw material, laying a foundation for the industrial production of the heavy alkyl benzene. The complete process technology comprises the steps that C16-C19-containing n-alkanes (heavy liquid wax) are used as raw material, and are partially dehydrogenated in the high temperature and low pressure hydrogenation state to generate C16-C19-containing n-alkenes; the n-alkenes are subjected to alkylation reaction with benzene under the condition of an HF acid catalyst to generate theheavy alkyl benzene; and then the heavy alkyl benzene is separated by a fractionating system to obtain the target product heavy alkyl benzene and a byproduct heavy component. A dealkylation column ofthe fractionating system is operated at a negative pressure to avoid the possibility that the heavy alkyl benzene and the heavy component are coked at a high temperature. The obtained product heavy alkyl benzene has stable compositions; the product after separation and purification has high purity, and the carbon number range of the product can be controlled; and the complete process technology solves the problem of raw materials of the heavy alkyl benzene for oil displacement from the source, opens up a new processing field of the heavy liquid wax and can meet the market demand of the high-quality heavy alkylbenzene.

Description

technical field [0001] The invention relates to the technical field of industrial production of heavy alkylbenzenes, specifically a process for producing heavy olefins by dehydrogenating heavy liquid wax and then alkylating heavy alkylbenzenes. Background technique [0002] As an important fine chemical, heavy alkylbenzenes are increasingly used in many fields. At present, the main source of heavy alkylbenzene is light liquid wax (C 10 ~C 13 ) is the by-product of the alkylbenzene plant as the raw material, and the by-product only accounts for 5% of the total output. [0003] my country began to introduce UOP technology to produce LAB in the 1970s. After entering the 1990s, the output increased rapidly. In 2004, it exceeded 500,000 tons / year. In 2016, the production capacity reached nearly 1 million tons / year, and the output was about 700,000 tons / year. Calculated at a ratio of 5%, the output of heavy alkylbenzene by-products of alkylbenzene plants in the country is only...

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Problems solved by technology

[0007] my country began to introduce UOP alkylbenzene production technology in the 1970s, which uses light liquid wax (C 10 ~C 13 ) as raw material to produce alkylbenzene. This technology has been introduced for more than 40 years and has exceeded the patent protection period. The main component of heavy alkylbenzene by-product of this technology is C 14 linear alkylbenzene, C 11 ~C 13 Diphenylalkane, dialkylbenzene, indane, tetralin, etc., the carbon number is difficult to control, the composition is extremely unstable, which seriously affects the separation and purification of heavy alkylbenzene

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