A whole fraction crude benzene hydrogenation process

Abstract

The invention discloses a whole fraction crude benzene hydrogenation process. The whole fraction crude benzene hydrogenation process comprises the following steps: firstly separating the raw material of crude benzene into crude benzene I and crude benzene II, mixing the crude benzene II with the crude benzene I after the first stage and the second stage of prehydrogenation in sequence, and then entering the third stage of main hydrogenation. Through the three stages of hydrogenation process, the reaction temperature is improved stage by stage from the low temperature of 70 DEG C, unsaturates such as styrene and diolefin in the crude benzene can be effectively removed, and the unsaturates can also be prevented from being coked under high temperature. Moreover, through pre-fractionation before hydrogenation, the hydrogenation are enriched in the crude benzene II, so that only the third stage of main hydrogenation is preformed on the crude benzene I, the pressure of prehydrogenation in the first stage and the second stage can be alleviated, and the defect that the saturation factor is increased through repeated hydrogenation of benzene in the crude benzene I can also be avoided.

Description

Technical field [0001] The invention belongs to the technical field of coal chemical industry, and specifically relates to a crude benzene hydrogenation process. Background technique [0002] Crude benzene hydrorefining can be divided into high temperature hydrogenation and low temperature hydrogenation according to its hydrogenation reaction temperature. The most typical high temperature hydrogenation process is the Litol method, and the representative of the low temperature hydrogenation process is the KK method. In the above two hydrogenation processes, crude benzene needs to undergo pre-hydrogenation to remove diolefins, styrene and other substances before deep desulfurization and denitrification reactions can be carried out. This is mainly because the unsaturated compounds such as dienes and styrene contained in the crude benzene raw materials are easily polymerized at high temperatures, forming a kind of dense structure of coke, blocking the catalyst channels, making the ca...

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Problems solved by technology

[0008] The object of the present invention is to address the above-mentioned deficiencies, and provide a crude benzene hydrogenation refining process suitable for industrialization. The method does not require pre-separation treatment of crude benzene, no waste of raw materials, and increased product added value. At the same time, the three-stage hydrogenation process , which fundamentally solves the problem of easy coking in the crude benzene hydrogenation process and prolongs the operating cycle of the unit

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