Method and device for continuously neutralizing beta-naphthalene sulfonic acid and comprehensively recycling waste gas

Abstract

The invention discloses a method and a device for continuously neutralizing beta-naphthalene sulfonic acid and comprehensively recycling a waste gas. According to the method and the device, sodium hydroxide and sodium carbonate are adopted for two-stage continuous neutralization on a sulfonation material, sodium hydroxide is used for continuously neutralizing free acid in the sulfonation material in first-stage neutralization reaction, sodium carbonate is used for continuously neutralizing beta-naphthalene sulfonic acid in second-stage neutralization reaction, the neutralization reaction is thorough, the beta-naphthalene sulfonic acid obtained from the reaction is relatively high in purity, low in impurity content and relatively good in neutralization effect, and carbon dioxide generated from the second-stage neutralization reaction can be recycled, treated and used as a raw material for later carboxylation reaction, so that comprehensive utilization of resources is achieved; no sulfur dioxide which is hard to treat is generated in the neutralization process, the environment is slightly polluted, the corrosion to equipment pipelines is alleviated under same capacity, the construction investment is small, good economic and environment benefits are made, the cost of companies is lowered, and the production requirements of energy conservation, emission reduction and environment-friendliness are met.

Description

technical field [0001] The invention belongs to the technical field of beta-naphthalenesulfonic acid neutralization, and in particular relates to a method for continuous neutralization of beta-naphthalenesulfonic acid and comprehensive utilization of waste gas recovery and a device thereof. Background technique [0002] β-naphthalenesulfonic acid is an important intermediate used in the production of dyes, pesticides and drugs, and is prepared from naphthalene as a raw material through sulfonation. At present, in industrial production at home and abroad, sodium sulfite produced by alkali fusion is neutralized with naphthalene-removed sulfonated hydrolyzate to obtain β-naphthalene sulfonate. The neutralization reaction produces a large amount of SO2 gas, which is then used for β-naphthalene sulfonate. Acidification and acidification of naphthol. Alkali fusion products are mainly sodium sulfite and sodium 2-naphthol, which are all soluble in water. During the acidification an...

AI Technical Summary

Problems solved by technology

Alkali fusion products are mainly sodium sulfite and sodium 2-naphthol, which are all soluble in water. During the acidification and acid analysis of β-naphthol, sodium sulfate with a concentration of about 8.5% is simultaneously generated. At the same temperature, due to the solubility of sodium sulfate Higher than sodium sulfite, so the effective concentration of sodium sulfite solution decreases, and the dosage increases, which leads to an increase in the amount of waste water, and the loss of the target product sodium β-naphthalenesulfonate is relatively large

Production statistics show that every ton of β-naphthol produces about 8-12 tons of waste water, the loss of target product β-naphthalene sulfonate is about 700kg, and the high-salt organic wastewater (the concentration of β-naphthalene sulfonate is about 7%) is difficult to control, which has become a major environmental protection technical problem that restricts the production of β-naphthol; at the same time, the sulfur dioxide gas produced by the neutralization reaction severely corrodes the equipment and pipelines. Provide driving force, insufficient contact with the solution, resulting in incomplete neutralization reaction, so it has a greater impact on the environment

At the same time, the sodium sulfite produced by alkali fusion is used to neutralize the naphthalene-removed sulfonated hydrolyzate, but the neutralization effect is not good, the impurity content in the obtained product is high, and the cost of raw materials is high, which leads to the production cost of the enterprise cannot be reduced, and it is difficult to achieve energy saving and emission reduction. goals of cleaner production

Images