Dehydrogenation ammoniation method for producing pyrrolidine with 1,4butanediol

Abstract

The method belongs to a method for producing tetrahydropyrrole. The method comprises the following steps: taking 1,4-butyleneglycol, ammonia and water with the mol ratio of 1:1.3-2:0.4-3 as raw materials, heating and vaporizing to reach reaction temperature of 240-330 DEG C, introducing into a reactor at the weight space velocity of 0.6-0.7g / min under the protection of nitrogen, passing through a gas-phase fixed bed filled with an SO4 / MxOy rare earth compound supported catalyst, performing catalytic reaction at the reaction pressure of 0-0.1MPa, condensing a reactant to obtain a solvent mixture, distilling and purifying the solvent mixture, and collecting a distillate with the temperature of 86-90 DEG C to obtain crude tetrahydropyrrole. In the method, the tetrahydropyrrole is synthesized by reaction in a low pressure state, a little water is added in the synthesis process to reduce difficulty in purifying and separating the product, and the method has the advantages of safety and high efficiency, simple production process, low production cost, energy conservation, easy wastewater treatment, easy environmental protection, and high raw material conversion rate and yield.

Description

technical field [0001] The invention belongs to a method for producing tetrahydropyrrole. Background technique [0002] Tetrahydropyrrole is a cyclic secondary amine with pKb=2.9, which has the properties of a general amine. fields have a wide range of uses. [0003] Its preparation methods in the past mainly include: tetrahydrofuran and ammonia catalytic synthesis method, hydrogenation denitrogenation method, etc. The synthesis of tetrahydropyrrole compounds can also be carried out by other methods, among which the more representative ones are: 1,4-butanediamine catalytic hydrogenation denitrogenation method, 1,4-butanedinitrile hydrogenation method, pyrrole hydrogenation method , pyrrolidone hydrogenation method, etc. These methods mainly react under the condition of hydrogen, have the disadvantages of harsh conditions, high equipment requirements, and difficult operation, and generally cannot be reacted under normal pressure. The high-pressure reaction requires high s...

AI Technical Summary

Problems solved by technology

These methods mainly react under the condition of hydrogen, have the disadvantages of harsh conditions, high equipment requirements, and difficult operation, and generally cannot react under normal pressure.

High pressure reaction requires high safety, equipment manufacturing and production costs are expensive, which is not conducive to increasing production capacity and large-scale industrial production

Most of the existing synthesis methods are medium and high pressure reactions. During the synthesis process, a large amount of water participates in the reaction, which wastes energy, increases the difficulty of product purification, and increases the difficulty and cost of sewage treatment.