Method for preparing epsilon-caprolactone by virtue of catalytic oxidation of cyclohexanone

Abstract

The invention relates to a method for preparing epsilon-caprolactone by virtue of catalytic oxidation of cyclohexanone. The method comprises the following steps: S1, according to the use amount determined in advance, adding a raw material (anhydride) into a reaction container filled with a raw material (aqueous hydrogen peroxide solution) and a catalyst, and controlling the temperature of a reaction system at 5-20 DEG C so as to prepare organic peracid; and S2, adding the generated organic peracid into the cyclohexanone, evenly mixing, controlling the temperature of the reaction system at 30-100 DEG C, continuously reacting for 1-15 hours, cooling and separating after reaction is finished so as to obtain the finished epsilon-caprolactone. According to the method, in the catalytic oxidation process, the selectivity of the catalyst and the yield of the epsilon-caprolactone are still improved even though water exists in the reaction system; in the reaction process, the water in the reaction system dose not need to be removed, thus the reaction condition is reduced so that the reaction process is mild and is easy to control; the reaction is high in safety and environmentally-friendly while the high yield and selectivity can be achieved, and the used catalyst is cheap and available, is easy to prepare, has no halogen elements and is high in stability.

Description

【Technical field】 [0001] The invention relates to the field of industrial catalysis in the petrochemical industry, in particular to a method for preparing ε-caprolactone by catalytic oxidation of cyclohexanone. 【Background technique】 [0002] ε-caprolactone is an important organic synthesis intermediate, mainly used for the synthesis of poly ε-caprolactone and copolymerization or blending modification with other esters; ε-caprolactone can also be used as a strong solvent, It can dissolve many polymer resins, and has good solubility for some insoluble resins, such as it can dissolve chlorinated polyolefin resins and "ESTANE" polyurethane resins. Among them, polyε-caprolactone (PCL) is a linear aliphatic polyester obtained by ring-opening polymerization of ε-caprolactone (CL). [0003] The synthesis of ε-caprolactone has difficulties in raw material quality, production safety and product stability, etc., so its synthesis technology is very difficult. At present, only a few co...

AI Technical Summary

Problems solved by technology

The synthetic methods of ε-caprolactone reported in the current literature also include the use of peroxyacid oxidation, low-concentration H 2 o 2 , O 2 / air etc. are oxidants to oxidize cyclohexanone to synthesize lactones and biological oxidation methods, but these methods have the following disadvantages: low activity of catalysts, poor yield and selectivity of ε-caprolactone, difficult recycling of catalysts, etc.