Close coupled catalyst for purification of exhaust gas and the preparation thereof

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A close coupled three-way catalyst for purification of exhaust gas of motor vehicle and the preparation thereof. The support is selected from cordierite honeycomb ceramic materials having a pore volume of 0.25-0.35 ml/g. The coating layer is the mixture of hexaaluminate and perovskite-type composite oxide, cerium-zirconium solid solution, rare-earth oxide and alumina, alkali-earth oxide and zeolite having a high Si/Al ratio. The active components are palladium-rhodium, rare-earth oxide and transition metal in the hexaaluminate and perovskite-type composite oxide. The catalyst has not only the function of low-temperature catalytic oxidation of hydrocarbons, but also the function of reduction of nitrogen oxides, and can be used for purifying the exhaust gas of motor vehicles using gasoline, liquid gas, or CNG as fuel.