PROCESS FOR THE PRODUCTION OF CARBONYL FLUORIDE OR CARBONYL CHLOROFLUORIDE BY ELECTROLYZING CARBONYL DIXHLORIDE OR CARBON MONOXIDE OPTIONALLY IN THE PRESENCE OF CARBONYL CHLORIDE, CHLORINE OR CHLORINE DONORS IN ANHYDROUS HYDROFLUORIDE ACID AT A CELL VOLTAGE OF FROM 4 TO 8 VOLTS AND AT A TEMPERATURE OF FROM -20 TO 20*C., THE CARBONYL FLUORIDE OR CARBONYL CHLOROFLUORIDE BEING REMOVED FROM THE REACTION GASES LEAVING THE ELECTROLYSIS CELL BY COOLING.