Impregnated Activated Carbon is made by impregnating activated carbon with specific chemical agents (such as iodine, silver, phosphorus, zinc and other metals or inorganic compounds) to give it specific adsorption and chemical reaction functions. The impregnated activated carbon has the ability to efficiently adsorb and remove certain specific pollutants, and is suitable for treating waste gas with chemical components, acidic gas, mercury and other harmful substances.