Diesel engine oxidation type catalyst with high thermal stability and preparation method thereof

The invention discloses a diesel engine oxidation type catalyst with high thermal stability and a preparation method thereof. The catalyst is composed of a carrier and a coating, wherein the coating is composed of precious metals which are platinum and palladium, modified alumina, an auxiliary agent and a binder; the loading capacity of the coating is 80-180 g/L; the loading capacity of the platinum is 1-100 g/ft , and the loading capacity of the palladium is 1-100 g/ft ; the mass ratio of the modified oxide to the aluminum oxide in the modified aluminum oxide is (0-20): (80-100); the massratio of the auxiliary agent to the modified aluminum oxide is (0-10): (90-100); the mass ratio of the binder to the modified aluminum oxide is (2-10): (90-98). The preparation method comprises the following steps: loading the platinum and the palladium on the modified alumina material, adding the auxiliary agent and the binder to prepare catalyst coating slurry, coating the honeycomb ceramic carrier with the coating slurry,