TECHNOLOGY FOCUS - ELECTRICAL POWER AND ENERGY - Preferred Method: The method involves the step of loading dust particles with an electric charge of a first polarity and loading a dust collector with an electric charge of a second polarity, opposite to the first polarity.Preferred Apparatus: The apparatus is adapted to be provided on a flow route of air supplied to the fuel cell. The first purifying device includes a catalyst that oxidizes the pollutant by means of oxygen in the air, and the catalyst has an oxidizing activity with respect to at least one selected from organic substance, nitrogen oxide, sulfur oxide, ammonia, hydrogen sulfide, or carbon monoxide; and includes an ozone generator that generates ozone, and the pollutant is oxidized by the ozone generated by the ozone generator. The second purifying device adsorbs and/or removes the pollutant by means of a porous material carrying at least one selected from permanganate, alkali salt, alkaline hydroxide, or alkaline oxide. Preferred Cell: The fuel cell further comprises a heating device for heating the first purifying device, where a fuel supply device contains a reformer, and the heating device heats the first purifying device by utilizing waste heat from the reformer; and a device for circulating cooling water through the fuel cell to cool the fuel cell, where the heating device heats the first purifying device by utilizing the cooling water which has been heated as a result of heat exchange with the fuel cell.The reformer is adapted to reform city gas. The first purifying device includes an ozone generating discharge element that generates ions, as well as ozone, to cause dust in the air to carry an electric charge, a dust collector is provided downstream of the discharge element, and the dust collector carries an electric charge of a polarity opposite to the polarity of the electric charge of the dust given by the discharge element for adsorbing the dust.An air supply device includes a blower for taking outside air into an air supply route, and (A1) containing a dust removal filter located upstream or downstream of the blower for removing dust in the air; an ozone generating discharge element located downstream of the blower for generating ions, as well as ozone, to cause dust in the air to carry an electric charge; and a dust collector located downstream of the discharge element, the dust collector carrying an electric charge of a polarity opposite to the polarity of the electric charge of the dust given by the discharge element for adsorbing the dust. (A1) Is located downstream of the discharge element, for oxidizing a pollutant in the air by reacting the ozone with the pollutant and for adsorbing and/or removing the oxidized pollutant. An air electrode is a cathode and a fuel electrode is an anode.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The catalyst is Pd, Pt, Ru, or Rh. The porous material is at least one selected from activated carbon, alumina, zeolite, or silica. EXAMPLE - As the first pollutant-removing device, MH80A (RTM; a honey-comb-shaped Fe-Cr-Al alloy carrying palladium) (277 ml) was put into a cylindrical container made of stainless steel. A heater was installed around the container, and the container was heated to 200degreesC. An inlet tube and an outlet tube were connected to the upper and lower parts of the cylindrical container, respectively. As the second pollutant-removing device, NC honeycomb (a honeycomb-shaped mixture of calcium hydroxide, potassium carbonate, calcium sulfate, and activated carbon) (600 ml) was put into a rectangular container made of stainless steel. An inlet tube and an outlet tube were connected to the upper and lower parts of the container, respectively. An air purifying apparatus was configured such that the air discharged from the first pollutant-removing device was cooled to room temperature by an air-cooled tube and then fed to the second pollutant-removing device. To this air purifying apparatus, air was fed by a blower to purify the air. As a result, all the air pollutants, NOx, SOx, and CO, were successfully reduced to at most 1 ppb (below minimum limit of detection).