Process for producing H acid by recycling alkali fusion mother liquor

Abstract

The invention relates to a process for producing H acid by recycling alkali fusion mother liquor, and belongs to the technical field of preparation for the H acid. According to the invention, sulfiteis used to replace potassium hydroxide or sodium hydroxide and is used as a neutralization solution of a denitrification reaction solution, and can be continuously recycled in the process of preparingthe H acid, so that the use amount of potassium hydroxide of which the concentration is 48% is reduced from 11 tons of the original process to less than 5 tons, and the use amount of sodium hydroxideof which the concentration is 48% is reduced from 8 tons originally to less than 3.5 tons, so that the consumption of potassium hydroxide or sodium hydroxide is greatly lowered to effectively lower the production cost of the product.

Description

technical field

[0001] The invention relates to the technical field of preparation of H acid, in particular to a process for producing H acid by continuously recycling mother liquor. Background technique

[0002] H acid (monosodium 1-amino-8-naphthol-3,6-disulfonate) is an important intermediate in the production of reactive dyes. At present, the production of H acid uses refined naphthalene as a raw material, and amino T acid is first prepared through sulfonation, nitration, denitrification, neutralization, reduction, sodium chloride salting out and other processes, and amino T acid is then subjected to alkali melting and acidification. Production of H acid, however, the mother liquor produced during the production of H acid belongs to the "five high" organic wastewater with high concentration, high acidity, high salinity, high chroma, and high toxicity, and the chemical oxygen demand (Chemical OxygenDemand-COD) is as high as 80,000 to 100,000, the salt content is as high ...