Technology for two-stage cross-flow extraction separation of mixed liquid of nitro T-acid, sulfuric acid and water

Abstract

Provided is a technology for two-stage cross-flow extraction separation of nitro T-acid, sulfuric acid and water. The steps are as follows: a complexing extraction technology is employed, a complexing extraction agent employs tributylamine as an extraction agent, employs benzene as a diluent and employs n-butanol as a promoter, a mixed liquid is subjected to two-stage cross-flow extraction, after layering separation, the extraction phase is subjected to rectification processing, the extraction agent is recycled, and nitro T-acid is obtained. In the optimization scheme, the mass ratio of tributylamine, benzene and n-butanol is 7:2:1, the volume ratio of a primary extraction raw material to the solvent is 1:1, and the volume ratio of a secondary extraction raw material to the solvent is 1:2. The final extraction rate of the extraction separation technology reaches more than 98%. The extraction phase solvent is recycled after processing of a rectifying tower. The extraction process is carried out at a room temperature, the extraction efficiency is high, the effect is good, high efficiency is achieved, and high economic benefit and social benefit can be generated.

Description

technical field [0001] The invention relates to a chemical extraction and separation process, in particular to a process for two-stage cross-flow extraction and separation of nitro-T acid-sulfuric acid-water mixed liquor. Background technique [0002] Nitro T acid, also known as 8-nitro 1,3,6 naphthalene trisulfonic acid, English name: [0003] 8-nitronaPhthalene1,3,6-trisulfonate, its structural formula is as follows: [0004] [0005] In the molecule of nitro-T acid, it contains naphthalene ring and -SO 3 The H functional group has the properties of Lewis acid. [0006] The hydrogenation reduction of nitro T acid can prepare T acid (1-naphthylamine-3,6,8-trisulfonic acid), and T acid is the preparation of H acid (1-amino-8-naphthol-3,6-disulfonic acid) acid monosodium salt). H acid is an important naphthalene dye intermediate, widely used in the production of acid dyes, direct dyes, reactive dyes and azo dyes, such as: reactive brilliant red X-3B, reactive black KN-...

AI Technical Summary

Problems solved by technology

[0009] Excessive sulfuric acid participates in the reaction process, resulting in a large amount of sulfuric acid in the reaction product, which is difficult to separate, the product content is low, the equipment consumption is large, and it is not conducive to the next reduction to generate T acid

[0010] The traditional separation and purification method of nitro-T acid and sulfuric acid mixture: one is to use n-butanol as the extractant, but it only has a certain extraction effect on the solution with a concentration below 8%, and due to the mutual solubility of water and n-butanol Higher, resulting in low extraction efficiency and poor extraction effect; the other is to use trioctylamine as complexing agent, NaOH solution as stripping agent, to obtain nitro T salt solution, and the separated product changes

Images