CATALYST FOR EXHAUST GAS PURIFICATION AND ITS MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a catalyst for exhaust gas purification which is improved in gas diffusion properties and enhanced in oxygen storing and discharging power with regard to the catalyst for purifying an automotive exhaust gas and the like.

SOLUTION: The catalyst coating layer contains at least the powder of an oxygen storing and discharging material and has pores with a center pore diameter of 0.1 μm or larger, and the pore volume of the pores within the range of ±50% of the center pore diameter is made to be 0.05 cc/g or larger. Since the catalyst coating layer has a macropore, the gas diffusion properties are improved and the contact probability between the oxygen storing and discharging material and an exhaust gas is increased. Consequently, the oxygen storing and discharging power is enhanced and the purification rate is remarkedly increased as the catalyst coating layer is easily heated by the exhaust gas and reaches an activation temperature in a short time.

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