Industrialized production method and device for 2,5-dimethyl-2,5-hexylene glycol

Abstract

The invention discloses an industrialized production method and device for 2,5-dimethyl-2,5-hexylene glycol, and belongs to the technical field of chemical industry production. The production method includes the steps that with benzene being a solvent and potassium hydroxide being a catalyst, acetylene and acetone are used as main raw materials for an ethynylation reaction to prepare hexyne diol,and then a catalytic hydrogenation reaction is conducted, wherein after the ethynylation reaction, in the materials, carbon dioxide is adopted for conducting a neutralizing reaction with potassium hydroxide; potassium carbonate obtained through the neutralizing reaction is recycled. Carbon dioxide is adopted for replacing hydrogen chloride to neutralize potassium hydroxide, the usage amount of carbon dioxide is 35 kilograms for each ton of produced DHAG alcohol, the cost approximates to 80 RMB, but no special requirements for production equipment exist, the equipment is not corroded much moreand does not need to be replaced frequently, potassium carbonate generated after the reaction can be used as side products, implicit negative costs are high, the environment is not polluted, and the effect of environmental protection and economic benefits are improved greatly.

Description

technical field [0001] The invention relates to the technical field of chemical production, in particular to an industrialized green production method of 2,5-dimethyl-2,5-hexanediol. Background technique [0002] 2,5-Dimethyl-2,5-hexanediol, referred to as DHAG, is an important chemical raw material. So far, there are very few enterprises producing 2,5-dimethyl-2,5-hexanediol. There are only three major large-scale enterprises in the world distributed in Luzhou City, Sichuan Province, including the applicant, with an annual output of 5,000 tons; Luzhou Fubang Chemical Company, with an annual output of 2,000 tons. There are a few other companies such as Sichuan Yibin Hengde Chemical Co., Ltd. that produce this product, but on a smaller scale. [0003] At present, the method for producing 2,5-dimethyl-2,5-hexanediol is generally as follows: first, benzene is used as solvent, potassium hydroxide is used as catalyst, and acetylene and acetone are used as main raw materials und...

AI Technical Summary

Problems solved by technology

[0004] In addition, the existing method of using hydrochloric acid to neutralize potassium hydroxide has the following disadvantages: first, a large amount of potassium chloride waste is not easy to handle after neutralization; In addition, hydrochloric acid has a large specificity and strong corrosiveness; and because hydrogen chloride gas is extremely volatile, it strongly corrodes the inner wall of the equipment pipeline, resulting in a short service life of the equipment; in the actual production of hexanediol, the pipelines are lined with four The cost of fluorine pipelines is twice that of ordinary pipelines; the cost of enamel equipment is nearly three times that of ordinary carbon steel equipment, and the replacement cycle of equipment pipelines is still relatively frequent; and because the use of hydrochloric acid to neutralize the reaction terminal cannot be automated, often If there is a phenomenon of passing the end point, it is necessary to add acid and alkali repeatedly, resulting in unstable quality of intermediate products, resulting in affecting the yield of semi-finished products and high consumption of raw materials

[0005] That is to say, although the direct cost of hydrochloric acid is 40 yuan / ton of DHAG, the yield of semi-finished products is unstable, the consumption of raw materials is high, and the hidden costs such as by-product treatment and equipment corrosion replacement caused by the use of hydrochloric acid are high

[0006] In order to reduce the cost, the applicant of the present application has made a lot of efforts, such as CN201310285157.9 of the application, the method is to separate and recover a large amount of potassium hydroxide aqueous solution in the process of producing hexanediol, and neutralize it with hydrochloric acid. The potassium hydroxide remaining in the semi-finished product in the kettle is neutralized, thereby reducing the cost to a certain extent; but a small amount of hydrochloric acid is still used

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