The reduction of NO by potassium-containing activated carbons and briquettes prepared from a bituminous coal was investigated. Partial washing of KOH activated carbons produced samples with different potassium contents. Briquetting with a binder containing potassium, at different binder/coal ratios, also allowed carbons with different potassium contents to be obtained. The NO-carbon reaction was studied with a fixed-bed flow reactor at atmospheric pressure in two types of experiment: (1) isothermal reaction at 300-600 degrees C; (2) temperature-programmed reaction (TPR) in an NO-He mixture. The reaction products were monitored in both cases, allowing detailed oxygen and nitrogen balances to be determined. Both the potassium remaining in the activated carbons and that present in the briquettes act as a catalyst for the NO-carbon reaction. Therefore, the briquettes are active for NO reduction with the advantage of being produced by a much simpler process with no KOH consumption and no washing process. Furthermore, the briquettes can be moulded in the desired form with appreciable mechanical strength. The final potassium loading controls the capacity of the potassium-carbon samples for NO reduction. The reduction of NO by the potassium-containing briquettes is enhanced by the presence of oxygen.