| In Electron-Fenton, hydrogen peroxide is produced at cathode, due to low production efficiency and low current efficiency, graphite gas diffusion electrodes with high catalysis activity to the electro-generation of hydrogen peroxide are developed. Comparing to actived carbon fiber (ACF) electrode, graphite electrode and actived carbon gas diffusion electrode, the graphite gas diffusion electrode had more functional advantages.The morphology of the electrode was observed by means of SEM and the performance of the graphite gas diffusion electrodes was tested by means of TG, DSC and CV.Preparation methods of the graphite gas diffusion electrodes had a big influence on the function of electrodes. Experimental results showed that when the electrodes was calcined at 350℃for 1 h and the mass ratios of graphite: polytetrafluorethylene was of 2:1, the catalysis activity of the electrodes was the highest. The operational parameters as pH,current intensity and temperature influenced the production of hydrogen peroxide greatly. The results showed that at pH=3~9 the catalysis activity of the electrodes was higher and stable, only at pH=1 the catalysis activity being lower. When the current density was 3 mA·cm-2, the catalysis activity of the electrodes was the highest. Temperature has effect on this system at less extent.The graphite gas diffusion electrode was modified in solution containing HNO3 and H3PO4. The performance of electrode which was made from modified graphite power was better. When pH value of the solution was 3, the current efficiency was higher than 72%, and the concentration of H2O2 achieved 274.5 mg·L-1, during the electrolysis for 150 min.
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