Research On Cogeneration Of Hydrogen Peroxide Cathodic And Ammonium Persulfate Anodic

Hydrogen peroxide and ammonium persulfate are very important industrialchemicals. The method of hydrogen peroxide production includes electrolysis-hydrolysis method, anthraquinone method, oxygen reduction method and so on. Theammonium persulfate is mainly produced by electrolysis at the anode. In order toimprove the current efficiency and the energy consumption, the paper improves theoxygen reduction method and the electrolysis process. The cogeneration of hydrogenperoxide cathodic and ammonium persulfate anodic is tried to achieve by increasing theanodic oxygen evolution overpotential.The electrochemical system of ammonium persulfate production and hydrogenperoxide production are studied to draw the Eh-pH diagrams of S-H2O system and theO-H2O system. Then the theoretical calculation of the cell voltage is carried out. Theorthogonal experiment is designed to study the influence of factors on the concentrationof ammomium persulfate and the current efficiency. The factors cover the concentrationof sulfuric acid and ammonium sulfate, the amount of ammonium thiocyanate and thecurrent density. The influence of the factors on the concentration of ammoniumpersulfate and the current efficiency is studied through intuitive analysis and varianceanalysis. The additional experiment is designed to study the optimum operatingconditions. The gas diffusion electrode is prepared to study the production of hydrogenperoxide. The best gas diffusion electrode is selected to study the cycle electrolysisexperiment. And the efficiency of cogeneration of hydrogen peroxide cathodic andammonium persulfate anodic is studied. Methods of membrane distillation and vacuumdistillation are used to concentrate the dilute hydrogen peroxide solution, because thatthe concentration of hydrogen peroxide produced by oxygen reduction method is low.The theoretical analysis proves that the cogeneration of hydrogen peroxidecathodic and ammonium persulfate anodic is feasible by increasing the anodic oxygenevolution overpotential. The energy consumption will be reduced.The intuitive analysis and variance analysis show that the effect of ammoniumthiocyanate and current density on the concentration of ammonium persulfate and thecurrent efficiency is greater than sulfuric acid and ammonium sulfate.. The optimumoperating conditions are as following, ammonium sulfate concentration240g/L,sulfuric acid concentration250g/L, current density0.9A/cm2, ammonium thiocyanate concentration1.2g/L. Under the best conditions, the current efficiency is about77.8%after1hour’s electrolysis.The experiments of hydrogen peroxide production and cycle electrolysis indicatethat the concentration of hydrogen peroxide can be further enhanced by circulating theelectrolyte and regularly supplying the fresh electrolyte. After12h, the hydrogenperoxide solution,50mL of3.5wt%, is produced.The cogeneration of hydrogen peroxide cathodic and ammonium persulfate anodicshows that the improved system can supply the H+consumed by cathode to reduce theelectrode polaration, promoting the production of hydrogen peroxide. Under optimumconditions of both anode and cathode, the current efficiency is maintained over130%in1hour.The distillation results show that the effect of membrane distillation is poor, takingtoo long time. The vacuum distillation can effectively concentrate the dilute hydrogenperoxide solution, and the short time consumed, less loss of hydrogen peroxide.