SU122747A2 - Method for isolating 1-anthraquinone sulfonic acid - Google Patents

Description

BASIC Auth. St. No. 119876 describes a method for separating a, a-disz lfolonic acids of anthraquinone from sulfomass obtained by sulphonating anthraquinone with oleum in the presence of mercury or its compounds, the purpose of which is to release the final (target) product from mercury compounds. In one of the variants of this method, at the end of the sulfonation process, chlorosulfonic acid is added to the reaction mass, after which disulfonic acid containing very small amounts of mercury is extracted from the sulfamase in the usual way.

The described version of the method according to ed. St. No. 119876 is proposed to be used in the isolation of 1-anthraquinone sulfonic acid from the corresponding sulfomass in order to reduce the mercury content in the resulting product. And in this case, chlorosulfonic acid, introduced directly into the sulfomass after the termination of the sulfonation process, destroys the organic complex containing mercury without causing any side processes that reduce the yield of sulfonic acid or deteriorate its quality.

Therefore, both the reverse anthraquinone and the sodium (or potassium) sulfonic acid salt, isolated from the treated sulfonic mass, contain very little mercury, since almost the majority of it goes into the waste filtrate as water-soluble sublimate.

Example. 52.5 g of freeze-dried anthraquinone sulfate 65 g of 2% oleum in the presence of 0.29 g of mercuric oxide, gradually raising the temperature to 130-135 ° and maintaining the set time (30-35 minutes) at this temperature. Then, at the sulfonation temperature, 1 ml of chlorosulfonic acid is poured into the sulfomass, after which the liquid can be kept for 10 minutes. at 130 °. Reverse anthraquinone is recovered from the sulphom.csy thus treated in the usual manner (for example, by pouring it on water), which is filtered and washed, and the sodium or potassium salt of α-sulfoxydote anthraquinone is salted out from the filtrate.

The content of mercury, inverse anthraquinone and in the salt of sulfonic acid does not exceed 0.02% by weight of the dry product.

Subject invention

A method for separating 1-anthraquinone sulfonic acid from sulfomass, characterized in that, in order to reduce the mercury content in the resulting product, the reaction mass after sulfonation is treated according to the method described in ed. St. No. 119876.