Development of Trickle‐Bed Electrolyzer for On‐Site Electrochemical Production of Hydrogen Peroxide

Abstract

A practical‐scale cell with a trickle‐bed electrode was developed for on‐site electrochemical production of hydrogen peroxide by the cathodic reduction of oxygen. Terminal voltage and current efficiency were affected by the dispersions of liquid and oxygen gas in the trickle‐bed cathode and by the current density. Current efficiency was improved by obtaining uniform dispersions of electrolyte and oxygen in the trickle‐bed cathode. A current efficiency of 97.4% was obtained at a cell voltage of 2.1 V and a current density of . To save power, the temperature of the electrolyte was not controlled, and exothermic reactions increased the temperature of the anolyte recovered at the outlet from the inlet temperature of 37–44°C. The temperature of the catholyte rose simultaneously from an inlet temperature of 25–44°C. The crystallization of sodium peroxide within the cathodes was prevented by controlling peroxide concentration, and the maximum concentration of hydrogen peroxide in a 5.0% caustic soda solution was 2.1%. © 1999 The Electrochemical Society. All rights reserved.