Extraction of Cerium from Catalyst of Waste Automobile Exhaust Gas Purifier

Automobile exhaust catalyst has been more and more widely used for creating a green life. It contains abundant platinum, palladium, rhodium, and rare earth cerium, compared with primary resources. It's necessary to efficiently recover valuable metals with great application value. The feasibility of leaching cerium from hydrochloric acid system is mainly analyzed from the perspective of thermodynamics in this paper. The leaching experiment of hydrochloric acid oxidation is carried out. The results show that the leaching rate of cerium reaches only 46% when the concentration of hydrochloric acid was 4 mol/L, the reaction temperature was 80 degrees C, the amount of hydrogen peroxide was 10 ml, the liquid-solid ratio was 10:1, the reaction time was 2 h, and the stirring speed was 450 r/min. According to the metal equilibrium, it is inferred that the formation of stable Ce-Zr solid solution makes the lower leaching rate of cerium.