Separation Between Benzene Disulphonate And Sodium Sulfate

Separation process has an important position in chemical industry. The experiments for separating the mixture of Benzene-1, 3-disulfonin acid and sulfuric acid from a chemical plant were studied by using the methods of chemical precipitation and complex extraction.The experiment for separating sulfuric acid from the Benzene-1, 3-disulfonin acid was studied by using the method of chemical precipitation. The results show that, by selecting Ca(OH)₂ as the precipitation separation reagent, the removal rate of sulfuric acid is 94.71%, the content of Benzene-1,3-disulfonin acid in the by-product of CaSO₄ is 2.64%, the content of Na₂SO₄ is 1.23% in the solid which is obtained by dehydrating the mother solution under the appropriate conditions. Different effects on the separation were discussed in details, such as raw material ratio, pH value of solution, reaction time, reaction temperature, volume of washing water and washing water temperature. Moreover, the conditions of the separation were optimized.Furthermore, the experiment for separating sulfuric acid from Benzene-1, 3-disulfonin acid was also studied by using the method of complex extraction. Selecting trioctylamine as the complex agent and using n-Octanol as the diluent, this article studied different effects on the extraction, such as concentration of complex agent, volume of extractant, acidity of solution, extraction temperature and resting time. Moreover, this article also studied different effects on the back-extraction, such as the volume of back-extractant, back-extraction temperature and resting time, and optimized the conditions of the separation. The results show that the extraction ratio of Benzene-1,3-disulfonin acid is 99.13%, the content of Benzene-1,3-disulfonin acid soldium salt is 2.64% in the solid which is obtained by dehydrating the raffinate phase; the content of Na₂SO₄ is 3.48% in the solid which is obtained by dehydrating the stripping aqueous phase. The extractant can be reused.