Abstract: The authors investigated the electrochemical reduction of oxygen to hydrogen peroxide in 0.05 mol/L H 2SO 4 solution by the trickle bed electrode using graphite chip. The bed dimension was 14×5×0.6 cm. The current efficiency and the concentration of H 2O 2 in the catholyte were determined at various current strengths and various rates of adding the electrolyte. The proper current was 0.15 A. i.e. the current density was 2.1 mA/cm 2 vertical cross section area of the bed. The concentration of H 2O 2 reached 7×10 -3 mol/L with the current efficiency of 0.2. If the concentration of H 2O 2 reduced to 4×10 -3 mol/L, the current efficiency might increase to 0.4.

Key words: Hydrogen peroxide, Electroreduction, Oxygen electrode, Trickle bed reactors