CATALYST LAYER FOR PURIFYING EXHAUST GAS, CATALYST STRUCTURE FOR PURIFYING EXHAUST GAS, AND METHOD FOR PURIFYING EXHAUST GAS THEREBY

摘要

PROBLEM TO BE SOLVED: To provide a catalyst layer which can remove NOx in dilute combustion exhaust gas efficiently, a catalyst-coated structure, and a method for purifying exhaust gas using them. ;SOLUTION: The catalyst A is composed of at least one kind of alkaline earth metal oxide selected from CaO, MgO, and BaO. A catalyst layer for purifying exhaust gas consists of the catalyst A and a catalyst B in which silver is contained in an alumina carrier having such pore structure that when in the relation between pore radii and pore volume measured by a nitrogen gas adsorption method, the total of pore volume occupied by pores whose radii are not exceeding 300 angstrom if made X, the total of pore volume occupied by pores whose radii are 25-100 is made Y, and the total of pore volume occupied by pores whose radii are 100-300 angstrom is made Z, Y is 70% or more of X, and Z is 20% or less of X.;COPYRIGHT: (C)1998,JPO