Synthetic method for sorbitan octoate emulsifier

Abstract

The invention discloses a synthetic method for a sorbitan octoate emulsifier. The synthetic method is characterized by being prepared from commercially available D-sorbitol, caprylic acid, a metal tin catalyst, a basic catalyst and a granular magnesium silicate adsorbent, which serve as raw materials, through processes of etherification, etherate refinement, esterification, deacidification, ester refinement and the like. According to the method, the metal tin catalyst is rationally selected and used; a product in the etherification process is subjected to adsorption and refinement treatment by utilizing the granular magnesium silicate adsorbent; unreacted caprylic acid is removed in vacuum at a high temperature; and a final product is subjected to adsorption and refinement treatment by utilizing the granular magnesium silicate adsorbent, so that the sorbitan octoate emulsifier which has the acid value less than 2.0 mgKOH / g, the color luster less than or equal to 100 Hazen, the hydroxyl value equal to 230-300 mgKOH / g and the saponification value equal to 180-210 mgKOH / g, is light in smell, high in transparency, low in fatty acid residue content, difficult in acid backflow and high in stability, and has good solubilizing, emulsification-facilitating, tackifying and anticorrosion-enhancing effects and safe and mild performance is obtained; and the method is suitable for the fields of daily chemicals and cosmetics, and the like.

Description

technical field [0001] The invention relates to a synthesis method of an emulsifier, in particular to a synthesis method of a sorbitan caprylate emulsifier, and belongs to the technical field of synthesis of ester compounds in organic chemistry. Background technique [0002] Sorbitan fatty acid ester is often used as W / O type emulsifier and is an important non-ionic surfactant with excellent emulsifying and dispersing properties. In addition, it is non-toxic, non-irritating, low-volatile and has no unpleasant smell. Due to its high critical micelle concentration and low micelle free energy, it can be widely used in industries such as petroleum, textiles, plastics, pesticides, food, cosmetics, and medicine. [0003] Sorbitan fatty acid ester products appeared in 1940. The earliest preparation method was to directly esterify sorbitol and fatty acid in a certain proportion in the presence of an alkali / acid catalyst at high temperature. The American I.C.I.A.M (formerly Atlas Pow...

AI Technical Summary

Problems solved by technology

The traditional one-step alkali-catalyzed process is mainly used in China. The products produced by this process have deep color, many by-products, low monoester mass fraction, mostly turbid state, and unstable quality.

The two-step synthesis process, esterification first and then etherification will easily lead to excessive esterification, high mass fraction of straight-chain esters, dark color, poor fluidity and poor transparency in liquid state, and it is difficult to reduce the hydroxyl value to the qualified range of the index. Especially in terms of product monoester, diester and polyester mass fraction, quality stability and color, there is still a certain gap compared with foreign countries.

However, due to the price of lipase and recycling problems, there is still a certain gap between it and industrialized production

[0004] At present, the research on sorbitan fatty acid esters mainly focuses on high carbon chain fatty acids such as lauric acid, palmitic acid, cocoic acid, oleic acid and stearic acid, and the synthesis method of sorbitan caprylate emulsifier is rarely reported.