Receiving triacetin from sunflower oil

Abstract

One of the promising types of vegetable raw materials in Ukraine, which can be used for the development of resource-saving technologies, are vegetable oils. The products of their processing serve as raw materials for obtaining surface-active substances, which are used in the production of food additives, pharmaceutical products, detergents and cosmetics, biofuels and additives. The most common oil in Ukraine is sunflower, which, like other vegetable oils, can be processed to form fatty acids and their salts. The initial process of vegetable oil processing is hydrolysis. The technological parameters of the sunflower oil hydrolysis process under different conditions were studied. It was investigated that the alkaline hydrolysis of sunflower oil in the presence of sodium hydroxide proceeds the fastest in comparison with thermal methods in the presence of sulfuric acid and superheated steam, the conversion of raw materials reaches 100 % in the 25th minute of the experiment, at a process temperature of 60 °C. The waste in this process is a glycerol solution, which can be used to obtain its esters for the purpose of implementing a zero-waste technology scheme. A method of using sunflower oil hydrolysis waste is proposed, which consists in its esterification with acetic acid, as a result of which triacetin is formed – a valuable product for use in many sectors of the national economy. In the food industry, triacetin is known as a food additive under the code E1518, which is used as a humectant and stabilizer to preserve freshness, as a plasticizer and binder thickener, as a solvent and odor fixer. Due to its ability to be broken down into its components – glycerol and acetic acid and absorbed without any side effects in the human body, triacetin is safe for use. It was investigated that the esterification reaction between the waste product of the hydrolysis of vegetable oil – a solution of glycerin in water and acetic acid took place at a conversion of raw materials of 100 %, while the selectivity of the target product remained constant at the level of 80 %. At the same time, the concentration of the glycerol solution did not affect either the amount of conversion or the value of selectivity. As a catalyst in this process, p-toluenesulfonic acid was used in a relatively small amount – 1.0 % by volume, so it did not significantly affect the composition of the reaction products, and this, in the future, makes it possible to conduct the process without additional purification from traces of the catalyst.