PURPOSE: To provide an electrolytic process and apparatus for oxidizing or reducing inorganic and organic species, especially in dilute aqueous solutions.

CONSTITUTION: An electrolytic reactor 10 contains an anode 12 and a cathode 14 which is allowed to be into contact with a packed bed of a particulate ion exchange material 16, which establishes an infinite number of transfer sites in the electrolyte to significantly increase the mobility of the ionic species to be oxidized or reduced toward the anode 12 or cathode 14, respectively. The above ion exchange material 16 is cationic for oxidation and anionic for reduction, or a combination of both for special circumstances. Preferably, the ion exchange material 16 is treated to convert a portion of the transfer sites to semiconductor junctions which act as mini anodes or cathodes to significantly increase the capacity of the reactor 10 to oxidize or reduce the species to be treated. Exemplary applications for this electrolytic process and apparatus are the conversion of halides to halous acids in dilute solutions.