Patent ID: 8524186

Claim:
A carbon-based catalyst for flue gas desulfurization that is brought into contact with a flue gas containing at least SO 2 gas, oxygen and water vapor so that the SO 2 gas can react with the oxygen and the water vapor to form sulfuric acid which is to be recovered, wherein, on a surface of the carbon-based catalyst, iodine, bromine or a compound thereof is added, ion exchanged or supported and a water-repellent treatment is applied to the carbon-base catalyst, wherein the carbon-based catalyst contains a resin having a contact angle with water of 90° or more as a result of the water repellent treatment, wherein, after a carbon-based catalyst is moistened to clog the inside of pores thereof with water, a solution containing iodine, bromine or a compound thereof is sprayed or sprinkled to the carbon-based catalyst or the carbon-based catalyst is dipped in the solution to add, ion exchange or support iodine, bromine or a compound thereof on a surface of the carbon-based catalyst, the carbon-based catalyst being moistened in such a way that the carbon-based catalyst and water are put in a vessel and the inside of the vessel is depressurized and, after maintaining the state for a certain time, is returned to atmospheric pressure, or that a mixed gas of water vapor and air is allowed to flow through the carbon-based catalyst to condense the water vapor.