External circular reaction device suitable for hydrogenation exothermic reaction

Abstract

The invention discloses an external circular reaction device suitable for hydrogenation exothermic reaction. The external circular reaction device mainly comprises a first-stage hydrogenation reactor, a second-stage hydrogenation reactor, a hydrogen circulation loop and a liquid circulation loop. The liquid circulation loop in the reaction device is used for mixing a part of reacted solution and a fresh raw material solution, so that the concentration of raw materials in the reactor is reduced, the bed temperature rise generated by a heat release effect caused by hydrogenation is relieved, and the temperature inside the first-stage hydrogenation reactor is effectively controlled. A way that the raw material solution and hydrogen flow up in parallel is adopted in the first-stage hydrogenation reactor, a liquid phase is used as a continuous phase, and a catalyst is soaked into a reaction liquid, so that the reaction temperature of a catalyst bed keeps constant, meanwhile, the overhigh local temperature of a reaction site on the surface of the catalyst is avoided, furthermore, the occurrence of polymerization reaction of organic matters on the surface of the catalyst is effectively inhibited, the carbon deposition quantity on the surface of the catalyst is low, and the service life of the catalyst is remarkably prolonged. The external circular reaction device disclosed by the invention is suitable for continuously producing succinic anhydride by using maleic anhydride through catalytic hydrogenation and preparing 1- 4-butanediol by using butynediol through hydrogenation.

Description

technical field [0001] The invention relates to an external circulation reaction device with a liquid circulation loop and a gas circulation loop, which is suitable for hydrogenation exothermic reaction, specifically an external circulation hydrogenation reactor that can control the reaction temperature balance and has no hot spots at the same time . Background technique [0002] Polybutylene succinate (PBS), produced by esterification and polycondensation of succinic acid and 1,4-butanediol, is a leader in biodegradable plastic materials and has a wide range of uses. It can be used in bacteria or enzymes Under the action of the environment, it will eventually degrade into substances such as carbon dioxide and water, which is harmless to the environment. In addition, PBS has a high melting point and good performance. It is expected to replace general-purpose polyethylene or polypropylene and enter the field of general-purpose plastics to alleviate environmental pollution ca...

AI Technical Summary

Problems solved by technology

[0005] For the hydrogenation of maleic anhydride to produce succinic anhydride and the hydrogenation of 1,4-butynediol to produce 1,4-butanediol are strong exothermic reactions. When using a fixed bed as a reactor for continuous production, the hydrogenation reaction temperature is not easy control and there are hot spots, and the reactants are easy to coke and cover the surface of the catalyst, causing the problem of catalyst deactivation. The purpose of the present invention is to provide a method that can effectively control the reaction temperature, eliminate hot spots and coke in the reactor at the same time, and realize succinic anhydride and An external circulation reaction device suitable for hydrogenation exothermic reaction for continuous large-scale production of 1,4-butanediol

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