Esterification method of aliphatic acid

Abstract

A method for esterifying fatty acid, comprising: reacting fatty acid and alcohol at a temperature of 200-400° C. and a pressure of 4-12 MPa to collect fatty acid ester. The carbon number of said fatty acid is 10-30. Said alcohol is a straight chain or branched fatty alcohol with 1 to 6 carbons. Compared with the traditional esterification process, the method of the present invention not only has a higher fatty acid ester yield, but also does not require a catalyst, and the process flow is greatly simplified; there is no waste acid discharge and no pollution to the environment; the alcohol / acid molar ratio is low, Effectively improve the utilization rate of equipment, reduce the recovery of methanol, and significantly reduce energy consumption.

Description

technical field [0001] The present invention relates to the preparation method of fatty acid ester. Background technique [0002] Fatty acid and alcohol undergo esterification reaction to form fatty acid ester. The reaction of forming fatty acid ester is a reversible equilibrium reaction. Under normal operating conditions, long carbon chain fatty acid reacts even under stirring and vacuuming, and the water generated by the reaction is removed in time. , the response rate is also very slow. The boiling points of long-chain fatty acids are relatively high. In order to increase the conversion rate of long-chain fatty acids, the reaction generally requires a larger alcohol / fatty acid molar ratio and a longer reaction time. The alcohol / fatty acid molar ratio is even as high as 44.5:1. Under the condition of small alcohol / fatty acid molar ratio, using sulfuric acid as a catalyst will easily cause carbonization of reactants and side reactions, but p-toluenesulfonic acid with relat...

AI Technical Summary

Problems solved by technology

The disadvantages of adopting a high alcohol / fatty acid molar ratio are: 1. while improving the conversion rate of fatty acid, it reduces the conversion rate of alcohol and greatly reduces the utilization rate of equipment; 2. increases the recovery of alcohol, resulting in energy consumption Substantial Increase

Using lipase as catalyst, the main problem of this method is that the catalyst is expensive and easily deactivated in methanol

Moreover, the concentration of the product in the reactor is very low, and the cost of enrichment is expensive. If it is used for commercial production, many large reactors are required, and the investment in equipment is large.