Lactone production method

Abstract

A lactone production method is characterized in that a reaction is performed in the presence of a catalyst with a molar ratio of cyclic ketone, a solvent, and hydrogen peroxide of 1:(0-80):(0.2-20) and a mass ratio of the catalyst and the cyclic ketone of 1:1-100 at a temperature of 5-75 DEG C and a pressure of 0.1-6.0 MPa, and lactone is obtained through recovery; the catalyst comprises a molecular sieve which is a titanium silicon molecular sieve with a MFI crystal structure; the crystal grain has a hollow structure, and the cavity part of the hollow crystal grain has a radial length of 5-300 nanometers; the molecular sieve sample has a benzene adsorption quantity of at least 70 mg / g under a condition with a temperature of 25 DEG C, P / P0 of 0.10, and adsorption time of 1 hour, and as for the low temperature nitrogen adsorption of the molecular sieve, a hysteresis loop exists between an adsorption isotherm and a desorption isotherm. Compared with the prior art, the invention overcomes the disadvantages of complex production process, equipment corrosion, potential safety hazard existence, and severe environment pollution for traditional peroxy acid oxidation methods.

Description

technical field [0001] The present invention relates to a production method of lactone, more specifically to a method for producing lactone, especially ε-caprolactone, through Baeyer-Villiger oxidation of cyclic ketone and hydrogen peroxide. Background technique [0002] ε-caprolactone has the advantages of low viscosity, easy processing, and low VOC content. It is used as oligomer and denaturant in the process, which can improve the toughness, low temperature characteristics and reactivity and other functionalities; in terms of coatings, it is used as an improvement in solvents and latex coatings for automotive primers, surface coatings and various building materials. It can improve the toughness of the coating film, improve the low-temperature characteristics, reactivity, and increase the crosslinking density; in terms of adhesives, it can be used to improve the bonding properties of hot-melt adhesives and solvent-based adhesives; in resin modification On the one hand, it...

AI Technical Summary

Problems solved by technology

[0004] At present, the industrialized production of ε-caprolactone mainly adopts the Baeyer-Villiger oxidation process of cyclohexanone and peroxycarboxylic acid, but peroxyacid oxidants also have relatively large disadvantages: (1) after the reaction, a large amount of Organic carboxylic acid (salt) waste has a greater impact on the environment, and it is more difficult to recycle or process; (2) the separation and purification of reaction products are more difficult, the selectivity is low, the atom economy is poor, and it does not meet the basic principles of green chemistry; ( 3) Organic peroxyacids need to use high-concentration hydrogen peroxide in the production process, which is unstable in nature, high in production costs, and dangerous in transportation, storage and operation, thus limiting its application in industrial production

However, metal oxide catalysts have inherent defects in such reactions, such as low catalytic efficiency and small reaction conversion frequency (TON), which are difficult to solve and cannot be industrialized.

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