ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Influence of pretreatment of active carbon on the properties of porous carbon electrodes for preparing hydrogen peroxide by cathodic reduction of oxygen

J. Balej, K. Balogh, and O. Špalek

Institute of Inorganic Chemistry, Czechoslovak Academy of Sciences, 160 00 Prague

Abstract:  Preparation of hydrogen peroxide by cathodic reduction of oxygen in porous electrodes from active carbons without or with a thermal pretreatment at min. 1000°C either in vacuo or in the presence of alkali sulfides in an inert atmosphere at normal pressure was investigated. The current yields of hydrogen peroxide on electrodes from untreated active carbons are initially very low and rise slowly with time up to ca. 15—25%. The thermal pretreatment of active carbon in vacuo results in a pronounced increase of current yields up to 60—80% (at 30 mA cm²); from this value they begin to decrease and after several hours they reach the level equal to that for untreated carbon. The most effective treatment consists in heating active carbon in an inert atmosphere with alkali metal sulfides; for this treatment the optimum temperature and time of heating were found. The lifetime of such electrodes reaches in best cases about one thousand hours. A continual feeding of the inlet electrolyte with catalytic poisons (HgO, As₂O₃) has no effect on current yields of hydrogen peroxide when using electrodes from untreated active carbon.

Full paper in Portable Document Format: 305a611.pdf

Chemical Papers 30 (5) 611–620 (1976)