84-23-1Relevant articles and documents
Method for preparing 6-nitro-2-diazo-1-naphthol-4-sulfonic acid hydrate
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Paragraph 0014; 0032; 0037-0038; 0041; 0046-0047, (2020/06/17)
The invention discloses a method for preparing 6-nitro-2-diazo-1-naphthol-4-sulfonic acid hydrate. The method comprises the following steps: carrying out a nitrosation reaction on 2-naphthol serving as a raw material, sodium nitrite and dilute sulfuric acid in a tubular reactor to generate 1-nitroso-2-naphthol, carrying out catalytic hydrogenation on the 1-nitroso-2-naphthol and hydrogen in a Raney nickel immobilized fixed bed reactor to generate 1-amino-2-naphthol, carrying out sulfonation diazotization cyclization on 1-amino-2-naphthol and nitrosyl sulfuric acid in the tubular reactor, and nitrifying with nitric acid to obtain the final product 6-nitro-2-diazo-1-naphthol-4-sulfonic acid hydrate. According to the novel synthesis method of the 6-nitro-2-diazo-1-naphthol-4-sulfonic acid hydrate, hydrogen is used for reduction in the route, nitrosyl sulfuric acid is used for sulfonation diazotization cyclization, so the problem that a large amount of solid waste is generated in a traditional route is avoided, the atom utilization rate is high, the yield is increased, the safety coefficient is increased by using a tubular process, and the method is suitable for industrial production.