Preparation method for sucrose fatty acid ester

Abstract

The invention provides a preparation method for sucrose fatty acid ester. The preparation method comprises the following steps: A) subjecting sucrose and alkyl stearate to a reflux reaction in a solvent mixture in the presence of potassium carbonate and potassium stearate so as to obtain a product mixture, wherein the solvent mixture is composed of dimethyl sulfoxide and dichloromethane in a volume ratio of 1: (3-8); B) adding a saturated sodium chloride solution into the product mixture, adjusting a pH value to 6.6 to 7.2, adding an extractant for extraction, carrying out liquid separation and taking an organic phase; and C) subjecting the organic phase to pressure-reduced concentration and carrying out drying by distillation so as to obtain sucrose fatty acid ester. The preparation method belongs to the technical field of chemical engineering, is simple in operation steps, optimizes a reaction system and reaction conditions, reduces the usage amount of dimethyl sulfoxide, decreases production of by-products, and improves product yield and purity; and the prepared sucrose fatty acid ester has low degree of substitution and excellent performance.

Description

Technical field [0001] The invention belongs to the technical field of chemical engineering, and particularly relates to a preparation method of sucrose fatty acid ester. Background technique [0002] Sucrose fatty acid ester (SE) is a product formed by the esterification reaction of sucrose and fatty acid. It has excellent surface activation properties and is widely used as an additive in food, cosmetics, and pharmaceuticals. [0003] The preparation methods of sucrose fatty acid esters include solvent method, solventless method and microemulsification method. The existing solvent method mainly uses DMF or DMSO as a solvent. These two solvents are thermally stable and have good compatibility with the reaction raw materials, but they have the problem of difficulty in subsequent purification. In the solvent-free method, the reaction system is melted into a homogeneous phase by adding active agents and other ingredients, and there is no problem of solvent residue, but the reaction t...

AI Technical Summary

Problems solved by technology

The existing solvent method mainly uses DMF or DMSO as the solvent. These two solvents have thermal stability and good compatibility with the reaction raw materials, but there is a problem that subsequent purification is difficult

The solvent-free method is to melt the reaction system into a homogeneous phase by adding active agents and other components, and there is no problem of solvent residue, but the reaction temperature is high, and the yield of the final product is difficult to reach a high level

The microemulsion method replaces the organic solvent with water. Although the problem of solvent residue is avoided, the reaction conditions are difficult to control, and the yield of the final product is low and the color is dark.

[0004] Chinese patent application 201310321886.5 discloses a solvent-free method for the preparation of sucrose fatty acid esters, in which sucrose and fatty acid methyl esters are reacted in the presence of a catalyst to generate crude sucrose fatty acid esters, which are washed with water to obtain relatively high-purity sucrose fatty acid esters, but this method There are disadvantages such as easy decomposition of sucrose, harsh reaction conditions, high viscosity of the reaction system, complicated post-treatment, and difficulty in preparing sucrose fatty acid esters with low substitution degrees.

[0005] Chinese patent application 94119201.6 discloses a solvent method for preparing sucrose fatty acid ester, which is obtained by separating and recovering sucrose fatty acid ester from the reaction mixture obtained by reacting sucrose and fatty acid alkyl ester in the presence of an alkali catalyst with dimethyl sulfoxide as a reaction solvent. During separation and recovery, adjust the pH of the aqueous phase to 3-7.5, perform the first liquid-liquid extraction and the second liquid-liquid extraction to remove DMSO, etc., and then separate and recover sucrose fatty acid ester from the organic solvent solution. Disadvantages of more complicated steps

Although this method reduces the consumption of dimethyl sulfoxide, the extraction efficiency is still not ideal.