SU412173A1 - - Google Patents

Description

one

This invention relates to a process for preparing sebacic acid for raw materials containing ricinolic acid.

A known method for producing sebacic acid from castor oil containing ricinolic acid in a mixture with other fatty acids (released by high-temperature hydrolysis), which consists of the following successive operations; alkaline destruction of ricinoleic acid to the sodium salt of W-oxydecanoic acid at 170-190 ° C.

Oxidation of sodium salt of W-oxycanoic acid to sodium salt of sebacic acid at 260–280 ° C; separation of ballast fatty acids from sodium salt of sebacic acid; decomposition of the sodium salt of sebacic acid by action of sulfuric acid at 0–3.5 and subsequent isolation of the target product with known tricks.

The need to use expensive and scarce castor oil as a raw material, a low yield of the final 1PO product relative to ricinoleic acid contained in oil, as well as a decrease in quality indicators (melt color) due to the high content of sebacic acid of fatty acids (ballast acid) ) does not allow wide use of the known method.

The purpose of the invention is to improve the raw material base, increase the yield and improve the quality of the target product.

This is achieved by using alkaline soap stocks as a source of raw materials from refining castor oil, which are treated with mineral acid, for example, sulfuric acid, and the resulting fatty acids are separated and alkaline destruction takes place at 210-230 ° C, and the target product is precipitated after separation of ballast acids at 5-2.0. Irichem soya istoki treated with sulfuric acid concentration of 10-20%, which is taken with an excess of 20%, at 80-90 ° C.

The resulting sebacic acid has a melt color of 4-b (versus 1-3 for the known and fatty acid content of 1.5 mg COY- / g (versus 2-2.5 mg /}. OH / g for the known).

The production of sebacic acid by the alkaline destruction of ricinoleic acid contained in fatty acids isolated from castor soap stocks.

A batch of soap solution (soap stock) is loaded into a heated apparatus, heated to 95 ° C and treated intensively with technical sulfuric acid (10–20% acid concentration), an excess of sulfuric acid was 20% against the stoichiometric amount required for the decomposition reaction. soap. Succinct fatty acids are decanted and sent for degradation. In the destructor, in excess of alkaline liquids at 210-230 ° C, the destruction of the nitric acid contained in the mixture of selected fatty acids is carried out. The feed rate of fatty acids and water is 8.5 l / min, the time for feeding fatty acids is 5 hours, and water is 7 hours. Over the next 2 hours, raise the temperature of the reaction mass to -270 ° C and hold at 270-290 ° C for 6-7 hours. The resulting alkaline smelt is dissolved in water in a ratio of 1: 7, respectively, at 90-95 ° C, acidified with sulfuric acid to 5-5.6 to destroy the soaps and separate the fatty acids.

The solution of the sodium salt of sebacic acid after separation of the ballast acids is subjected to further acidification with sulfuric acid to 5-2.0 to decompose the sodium salt and precipitate sebacic acid.

After crystallization and separation of the crystals, the sebacic acid is dried at

PO-120 ° C with hot air until moisture content is no more than 0.2%.

Data on the comparative composition of the feedstock and the yield of sebacic acid in five experiments are given in Table. one.

The data of the optical parameters of the sebum | Nm production of sebacic acid by the proposed method are given in Table. 2

The data in table 1 show that the output

of sebacic acid obtained by the proposed method from ricinolic acid, contained in fatty acids, separated by decomposition of castor soapstock with sulfuric acid, based on the content of pure

ricinolic acid averaged 50.1%, while the yield of sebacic acid obtained in a known manner was -45.6%.

The content of proteins, mucus and carbohydrates in

fatty acids obtained by decomposition of sulfuric acid of castor soap stocks, defined as the sum of hydrophilic substances, -0.04-0.16% versus 0.81-1.23% in fatty acids obtained by hydrolysis of castor

oils.

Table I

Subject invention

Claims (2)

1. A method for producing sebacic acid from a raw material containing ricinolic acid, using alkaline destruction when heated, oxidizing to the sodium salt of sebacic acid, removing ballast acids, and precipitating the product by decomposition with mineral acid, characterized in that, in order to expand the raw material base, increase the yield , and improving the quality of the target product, use alkaline soot stocks from the refining of castor oil, which are treated with mineral acid, for example, sulfuric acid, section was obtained with fatty acid and alkaline degradation is carried out at 210-230 ° C and the desired product is precipitated after separating ballast acids at, 5-2,0. 2. A method according to claim 1, characterized in that the soap stock is treated with sulfuric acid with a concentration of 10-20%, which is taken with an excess of 20%, at 80-90 ° C.