Method for preparing cyclopentanol from cyclopentene

Abstract

The invention relates to a method for preparing cyclopentanol from cyclopentene. Cyclopentene and acetic acid are mixed for an esterification reaction, cyclopentyl acetate is generated, a catalyst adopts cerium nitrate modified sulfonyl cation exchange resin during a transesterification reaction, and the exchange capacity of cerium ions is 10%-30% of that of resin mass; the conversion rate of the esterification reaction is remarkably increased; during the transesterification reaction of crude cyclopentyl acetate and methanol, the transesterification reaction is catalyzed through granular CaO and a sodium methylate composite catalyst dissolved in a reaction liquid, cyclopentyl acetate and methanol can be catalyzed for the transesterification reaction, a small amount of water brought into reaction raw materials can be removed, difficulty caused by CaO hydrolysis and product separation is avoided, and the pollution problem of an existing process is effectively solved.

Description

technical field [0001] The present invention relates to a kind of method that prepares cyclopentanol by cyclopentene, relate in particular to a kind of solution of cyclopentene and acetic acid through the fixed-bed catalyst bed layer that is made of the sulfonic acid group cationic exchange resin that is modified with cationic The addition reaction is converted into cyclopentyl acetate, and then the mixed solution of methanol and CaO / sodium methoxide is used for transesterification reaction to prepare cyclopentyl alcohol. Background technique [0002] Cyclopentanol is an important intermediate of fine chemical products, mainly used in the preparation of bromocyclopentane, chlorocyclopentane and methyl cyclopentyl ether. Cyclopentanol can be prepared from adipic acid through high-temperature decarboxylation to cyclopentanone, and then hydrogenated. However, due to the large amount of pollutants produced and the cost of raw materials, this preparation method is increasingly li...

AI Technical Summary

Problems solved by technology

Although indirect hydration has the advantages of high conversion rate and good selectivity, due to the use of concentrated sulfuric acid in the preparation process, the requirements for corrosion resistance of equipment are extremely high, and the recovery of concentrated sulfuric acid is difficult, causing serious environmental pollution.

The direct hydration process does not have these problems, but the disadvantages of this method are that the reaction conversion rate is relatively low, the circulation of raw material cyclopentene is large, and the product refining energy consumption is high.

[0004] According to the thermodynamic theoretical calculation results of cyclopentene and acetic esterification reaction, the lower the temperature, the smaller the molar ratio of cyclopentene to acetic acid, the higher the equilibrium conversion of cyclopentene, but if the temperature is too low, the reaction rate will Also can reduce, be unfavorable for the carrying out of reaction, therefore be necessary to improve the conversion efficiency of reaction by developing a kind of active higher esterification catalyst, use catalyzer CaO to catalyze cyclopentyl acetate and methyl alcohol to carry out transesterification reaction in addition, although effect is relatively Good, but due to the small amount of water brought into the system or the reaction raw materials, the catalyst CaO will be hydrolyzed into calcium hydroxide, accompanied by the generation of calcium acetate, which brings difficulties to the separation of products and produces more serious pollution

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