Study On The Process For Electrosynthesis Ammonium Persulfate From Ammonium Sulfate

Ammonium persulfate is an important organic synthesis initiator, oxidant and additive. With the rapid development of organic synthesis, electronics and dye industries, the need of ammonium persulfate is yearly increased worldwide, but its supply is insufficient. Many processes have been thus explored in order to increase the production of ammonium persulfate. Among which, electrosynthesis has been found to be a better one for the ammonium persulfate production because of its simpleness, easy operations, reduced wastes, and high-product purity. Ammonium sulfate, which is a by-product of p-aminophenol via direct electroreduction of nitrobenzene, and of niacin or isoniacin synthesis via direct electrooxidation of 3-picoline or 4-picoline, was used as the raw material for the electrosynthesis of ammonium persulfate in this paper. The research contents of this paper are one of subjects funded by Henan Key Research Projects (No. 032304820 and No. 032304900). The main contents of thesis included: the wash of ammonium sulfate by-product, the electro-catalytic activity and selectivity of anode materials, and the optimization of the operate conditions for the ammonium persulfate electrosynthesis. This have a great science and applied significance for electrochemical synthesis of p-aminophenol, niacin and isoniacin.If the by-product ammonium sulfate was direct used for ammonium persulfate electrosynthesis, the organic materials in p-aminophenol etc. In this thesis, the optimal washing condition was attained, that is anhydrous ethanol as the solvent, the ratio of ammonium sulfate and ethanol being 1:3, the operation temperature being 60°C, and the wash time being 2 hour.The anode is the catalyst and a reaction field for electro-catalytic reaction. Base on the properties of the electro-synthesis process of ammonium persulfate and with the methods of steady-state polarization curve, the electro-catalytic properties of Ti/PbO₂, DSA, Ti/Pt and Pt electrode were investigated, respectively. It was found that the Pt and Ti/Pt anodes exhibited higher overpotential to oxygen evolution, better electro-catalytic activity and ammonium persulfate selectivity, and can be applied in...