Aminopyrine production method

Abstract

The invention relates to an aminopyrine production method, which comprises the following steps of: the preparation of sulfuric acid antipyrine, nitrosation, first hydrogenation reduction reaction, second hydrogenation reduction reaction, and decoloring, crystallization and drying performed on the crude product of the aminopyrine obtained by the second hydrogenation reduction reaction. Filter-pressing reaction is added between the first hydrogenation reduction reaction step and the second hydrogenation reduction reaction step, and comprises the following steps of: adding activated carbon and the oily 4-amino antipyrine obtained in the first hydrogenation reduction reaction step into a decoloring tank, controlling the temperature to be 80 to 90 DEG C, stirring the solution, adjusting a pH value to be 7.0 to 7.5, and then performing the filter-pressing on the solution in the decoloring tank with a three-liner filter to obtain 4-amino antipyrine filter-pressing liquid. The method has the advantages of improving the yield of the aminopyrine at the premise of ensuring the quality of the product, improving the working environment, saving labor, reducing labor intensity, saving energy, reducing emission and reducing the production cost.

Description

technical field [0001] The invention relates to a production method of aminopyrine. Background technique [0002] In the prior art, the production method of aminopyrine comprises the following steps, [0003] The preparation of antipyrine sulfate, antipyrine and sulfuric acid molar ratio is 2: 1 ratio reacts to obtain antipyrine sulfate; Nitrosation reaction, carries out nitrosation with described antipyrine sulfate and sodium nitrite Reaction, obtain nitroso antipyrine, the mass ratio of described antipyrine sulfate and sodium nitrite is 1: 0.35~0.40; The first hydrogenation reduction reaction, described nitroso antipyrine in catalyst Reynolds nickel Under the action of hydrogenation, feed hydrogen to carry out hydrogenation reduction reaction to obtain 4-aminoantipyrine oily substance; crystallization, put the 4-aminoantipyrine oily substance cooling crystallization obtained in the first hydrogenation reduction reaction step into the crystallization tank, open Cool the c...

AI Technical Summary

Problems solved by technology

[0004] In the existing aminopyrine production technology, after the cooling crystallization and centrifugation process of the 4-aminopyrine oily matter, there is about 15% 4-aminopyrine in the remaining solution after the aminopyrine crude product is crystallized, but the aminopyrine The remaining solution after the crystallization of the crude product is difficult to handle, which seriously affects the yield of aminopyrine. The production method is complex in operation, high in energy consumption, serious in pollution and low in yield

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