SU23502A1 - The method of obtaining sulfur dyes - Google Patents

Description

The present invention relates to a process for the preparation of sulfur dyes. For the purification of crude anthraquinone, usually containing non-oxidized anthracene as impurities, a significant amount of corbazole, phenanthrene, acrideno it. as well as oxidized products of the listed hydrocarbons, the method of sulphurization is used, which consists in the fact that the crude and trahinon is treated with concentrated sulfuric acid, and all the anthraquinone impurities give water-soluble sulfonic acids, whereas the anthraquinone itself remains in the sediment. After dilution with water, the anthraquinone is filtered off, the acidic filtrate containing the sulfonic acids of the anthraquinone impurities, is evaporated 2-3 times by volume, while the sulfonic acids: the anthraquinone mixtures drop as a gelatinous precipitate, filter and remove the BFJsar components and the optics that disappear. B in the form of neutral salts are fed to baking with polysulfide at a temperature of 200-300 for 8-10 hours.

To increase the strength of the dye to sulfonic acids, various organic additives can be given. Another method to increase the strength of dyes can be pre-nitration of crude sulfonic acids with diluted nitric acid. The nitrosulfonic acid is salted out of solution and baked with polysulfide at a temperature of 200-300. The baking of nitrosulfonic acids of anthraquinone impurities can be carried out with the addition of various organic compounds.

Example 1. - 17 g of sulfonic acid admixtures are anthraquinous neutralized by soda. To neutralized sulphonic acid, 8 i of oxyazobepzole is added. A solution of polysulfide (tatrasulfide) is prepared from 100 g of sulfuric acid bo / o and 74 sulfur, into which is added a mixture of sodium salts of sulfonic acids and oxyazobepzole. The reaction mass is heated at a constant volume for 1-2 hours, then the solution is evaporated and the whole mass is baked at 25 {T for 7-8 hours. The resulting raw olive color dye is purified by a conventional method.

Example 2. Sulfonic acids are dissolved in triplicate. By weight of the amount of water and treated with a double-and-a-half amount of nitric acid beats. at. 1.4 for 8 hours at a temperature of 80 and at the end of I00. After an eight-hour treatment, the nitration product is salted out, filtered and pressed. 18V2 g of the nitrosulfur product is mixed with g of oxyazobenzene and introduced into a hot solution of half-sulfide (consisting of 100 g of sour sour 60% and 74 g of sulfur). Further processing and baking is the same as in Example 1.

Example 3. Sodium salts of sulphonic acids or 25% g of sulfonic acid forgens are carried into a hot solution of liquid sulfide consisting of 100 g of sodium hydroxide 74 g of sulfur. Further processing is the same as in example 1.

The subject matter of the invention.

1. A method for producing sulfur dyes, characterized by a TeM; that the filtrate from the anthraquinone precipitate, which is obtained by ordinary purification of anthraquinone by dissolving it in crucic sulfuric acid and diluting this solution, is evaporated to precipitate, which is filtered off, neutralized, and fused by usual methods with polysulfides at 200-300 ° C with oxyazobenzene underneath or without it .

2. Acceptance of the solvent by means of the method described in paragraph 1, characterized in that the precipitate obtained by evaporation of the filtrate and anthraquinone is nitrated by heating, the resulting product is salted, filtered off and melted with polysulfides.