NITROGEN DIOXIDE REMOVING PROCESS

摘要

PROBLEM TO BE SOLVED: To efficiently remove an NOx of low concentration and improve the regeneration efficiency regardless of the high or low relative humidity by passing gas to be treated through a layer filled with a material having the reducing action from a nitrogen dioxide to a nitrogen monoxide or the like and then passing the gas to be treated through a layer filled with a nitrogen dioxide adsorption and reduction removing agent. SOLUTION: Gas to be treated containing a nitrogen dioxide or a sulfur dioxide is passed through a layer filled with a material having the reducing action from the nitrogen dioxide to the nitrogen monoxide and then passed through a layer filled with a nitrogen dioxide nitrogen adsorption and reduction removing agent composed of a porous carbon material carrying a ruthenium compound. The material to be used is preferably the porous carbon material, and the nitrogen dioxide adsorption and reduction removing agent is preferably an agent carrying an alkali metal compound or an alkali earth metal compound. After removing the nitrogen dioxide, the material and the nitrogen dioxide nitrogen adsorption and reduction agent are heated up to 150-200 deg.C in air to desorb the adsorbed nitrogen dioxide.