abstract |
A device (catalytic converter) for purifying an exhaust gas. This device has a first catalyst for purifying a NOx of the exhaust gas. This first catalyst contains first and second powders. The first powder has a porous carrier and at least one noble metal loaded on the porous carrier. The at least one noble metal is selected from platinum, palladium and rhodium. The second powder has a first double oxide represented by the general formula (Ln1-alphaAalpha)1-betaBOdelta where alpha is a number that is greater than 0 and less than 1, beta is a number that is greater than 0 and less than 1, delta is a number that is greater than 0, Ln is at least one first element selected from La, Ce, Nd and Sm, A is at least one second element selected from Mg, Ca, Sr, Ba, Na, K and Cs, and B is at least one third element selected from Fe, Co, Ni and Mn. The device is improved in capability of purifying NOx contained in an oxygen rich exhaust gas. |