A kind of production method of vanillin-1,2-propanediol acetal

Abstract

The invention discloses a production method of vanillin-1,2-propylene glycol acetal. The production method comprises the following steps: firstly, cleaning a reaction still, dehydrating the reaction still and a condensing device thereof so as to enable the water content of the reaction still to be lower than 500 ppm; secondly, adding raw materials vanillin and 1,2-propylene glycol into the reaction still; thirdly, adding an acidic substance as a catalyst into the reaction still and uniformly stirring; fourthly, vacuumizing the reaction still and enabling the reaction still to be in a certain negative pressure state; fifthly, raising the temperature of the reaction still to required temperature and reacting at the required temperature for a certain time; sixthly, carrying out sampling detection on a reaction product, adding a certain amount of alkaline raw materials into the reaction still to neutralize the catalyst after the reaction product is qualified by detecting; seventhly, carrying out reduced pressure distillation on the unreacted 1,2-propylene glycol and finally distilling and collecting to obtain qualified vanillin-1,2-propylene glycol acetal. The reaction time of the production method disclosed by the invention is 3 to 8 hours; compared with the prior production method, the production method disclosed by the invention has the advantages that reaction time is greatly shortened; in addition, the use of an organic solvent benzene is avoided and further environment friendliness is realized.

Description

technical field [0001] The invention relates to the technical field of ethyl vanillin, in particular to a production method of vanillin-1,2-propanediol acetal. Background technique [0002] Vanillin-1,2-propanediol acetal is a new type of raw material commonly used in the fragrance industry in the past ten years. The domestic fragrance industry first discovered that this compound should pass through the essence containing vanillin and 1,2-propanediol. Detected by GC / MS. In 1998, the American Flavor and Extract Manufacturers Association (FEMA) announced the FEMA number of vanillin-1,2-propanediol acetal as 3905, and suggested the dosage in food as 2-999mg / kg. Since then, it has been used more and more widely in the spice industry, and there are more studies on it. [0003] Vanillin 1,2-propanediol is a spice with vanillin smell, it is colorless to light yellow or yellow viscous liquid, it is stable and does not change color in neutral or alkaline solution, but it is easy to...

AI Technical Summary

Problems solved by technology

[0005] In view of this, the purpose of this invention is to provide a kind of production method of vanillin-1,2-propanediol acetal, to solve existing method production vanillin-1,2-propanediol acetal exists reaction time is long, uses Benzene as a solvent has problems such as polluting the environment and food