Preparation method of barium diphenylamine sulfonate

Abstract

The invention provides a preparation method of barium diphenylamine sulfonate, aiming to solve the problems that existing barium diphenylamine sulfonate preparation methods are complex in processes and higher in costs, and produced barium diphenylamine sulfonate contains plenty of barium sulfate, thus reducing the sensitivity of barium diphenylamine sulfonate. The preparation method comprises the following specific steps: adding 5Kg of diphenylamine and 4-5L of concentrated sulfuric acid to a 20L conical flask; checking the sulfonation degree of a mixed solution in the 20L conical flask; adding 4-5L of water to the 20L conical flask to carry out hydrolysis reaction; pouring the mixed solution in the 20L conical flask into 50Kg of boiling water, adding 32-80Kg of 20-50% barium hydroxide hot solution while stirring the mixed solution, filtering the mixed solution after carrying out insulation and precipitation for two hours and respectively collecting filtrate and filter residues; heating the filtrate to 60-90 DEG C and adjusting the PH value of the filtrate to 6-7 with 10% of sodium carbonate solution; drying the filtrate in a vacuum drying oven. The preparation method is used in the field of chemical reagents.

Description

technical field [0001] The invention relates to a preparation method of barium diphenylamine sulfonate, which belongs to the field of chemical reagents. Background technique [0002] Barium diphenylamine sulfonate is white or light gray fine flaky crystalline powder, sometimes light blue, slightly soluble in water, slightly soluble in hot water, decomposed by heating, but does not melt, and is easily oxidized in air. It is mainly used as an indicator of ferrous salt and a redox indicator. The general preparation method is to obtain diphenylamine sulfonic acid by sulfonating diphenylamine with concentrated sulfuric acid, and then neutralize it with barium carbonate. However, there is a large amount of barium sulfate in the barium diphenylamine sulfonate produced by this method, which makes the barium diphenylamine sulfonate content lower, resulting in reduced sensitivity and seriously affecting the use. However, barium carbonate can only precipitate impurity sulfate, and the...

AI Technical Summary

Problems solved by technology

[0004] In view of this, the main purpose of the present invention is to provide a kind of preparation method of barium diphenylamine sulfonate, which can solve the complex process of existing barium diphenylamine sulfonate preparation method , The cost is high, and the barium diphenylamine sulfonate produced contains a large amount of barium sulfate, which leads to the problem of reduced sensitivity