Study On Doping Electrode Without Membrane For Sodium Hypochlorite Preparation And Its Catalytic Performance

In order to solve the low effective Cl amount of NaClO produced by the no membrane electrolytic NaCl.In this paper,RuCl₃ and?NH₄?₂IrCl₆ were used as the basic plating solution.The optimal method was selected by the orthogonal method.Electroplating electrodes with high effective chlorine yield were screened by adjusting plating time,plating temperature,and plating voltage.XRD,SEM-EDS,XPS and other instruments was employed to characterize surface morphology,distribution of Ru and Ir on electroplated Ti electrode.The relative concentration of different oxidation of the same element was also tested.The results as listed:1.The optimum conditions for electrode preparation are as follows:When the concentration of Ru³⁺,NH₄Cl,NH₂SO₃H and Al₂?SO4?₃ is 5,30,20 and 0.8 g/L,relatively;Temperature,time and voltage is 30?,300 s and-0.8 V,relatively.The Ru/Ti electrode electrocatalytic performance will be better.When the concentration of Ru³⁺,Ir³⁺and urea is 5,1 and 0.2 g/L,and plating temperature,time and voltage is 70?,300 s and-1.2 V,the electrocatalytic performance of Ru-Ir/Ti would be better.2.Optimized electrolysis conditions:current density 20 A/cm²,plate spacing 1 cm,electrolysis time 1 h,no series connection.When NaCl was electrolyzed at a pH of8-11 below 20?,the current efficiency was higher than the pre-optimized average.3.The electrochemical properties of Ru/Ti electrode and Ru-Ir/Ti electrode were characterized by the method of linear voltammetry and cyclic voltammetry.The results show that the electrolysis reaction is a reversible reaction.The stability of the generated NaClO is affected by ammonia nitrogen,organic nitrogen,nitrous nitrogen and reducing ions in the water.4.XRD,SEM-EDS,XPS and other instruments was employed to characterize the electroplating electrode.The results show that the Ru-Ir/Ti electrode is denser and more uniform than the Ru/Ti electrode,and its catalytic performance is better when NaCl is electrolyzed.By comparing different concentrations of Ru-Ir/Ti electrodes,catalytic activity of Ru-Ir/Ti electrode is better,the catalytic effect of Ir³⁺is worse than the Ru³⁺,but Ir³⁺can make the coating surface more uniform and dense,and increases the lifetime of the electrode.This study provides a method for preparing high-performance electrodes by electroplating.