The Application of High Surface Area Cordierite Synthesized from Kaolin as a Substrate for Auto Exhaust Catalysts

Abstract

AbstractCordierite is often used as substrate for three way catalysts for the treatment of automobile exhaust gases, mainly because of its high stability. In this paper, different synthesis methods of cordierite are systematically investigated with the aim to improve functionalities and surface properties. Amongst them, the conventional sintering method from kaolin was paid attention to, due to economic reasons and the high yield of obtained cordierite phase. With the aim to improve the porosity, burnable additives were added to the precursor powder and acid leaching was applied to treat the surface of the substrates. The latter was found to be the most efficient method, especially when dolomite and industrial aluminum hydroxide were added in the precursors. Surface area of the cordierite sample reaches 139 m2/g with acceptable mechanical strength. The increase of the cordierite surface area resulted in a higher loading of MnO2‐Co3O4‐NiO catalytic active phases, leading to higher activity for the complete oxidation of CO. The deposition of an additional ψ‐Al2O3 support layer, which is normally done for these kinds of applications, becomes superfluous.