Patent ID: 8652990

Claim:
A method for producing a catalyst for purification of exhaust gas, comprising the steps of: adding Zr ions to a solution containing a platinum hydroxide polymer; diluting the solution to which the Zr ions are added by using an aqueous ammonium acetate solution wherein a pH value of the diluted solution is within about a slightly acidic to neutral range with the value of 5 to 7; immersing a support made of Al 2 O 3 , SiO 2 , CeO 2 , ZrO 2 , or a composite oxide of any ones of these oxides in the diluted solution, while heating at 60 to 70° C., to thereby support the platinum hydroxide polymer on the support and to improve the adsorption ratio of the platinum on the support; and calcining the support, on which the platinum hydroxide polymer is supported, at 150 to 800° C.