Preparation of palygorskite coated cordierite as supports of manganese based catalysts for low-temperature NOx removal from diesel exhausts by NH3 selective catalytic reduction

Abstract

Cordierite honeycomb ceramic (CC) was immersed in PG–water mixed slurry to prepare a palygorskite (PG) coated CC as a catalyst carrier (PG–CC). The preparation conditions for the coatings were optimized, and the PG coatings were extensively characterized. The calcination temperature, the solid-to-liquid ratio and the particle size of PG were the most influential parameters determining the coating's textural and mechanical properties. The results showed that the layer surface area of PG was drastically increased, and the PG exhibited perfect adhesion even after being subjected to ultrasonic vibration. After adding MnO_x, the obtained Mn₁₃/PG–CC catalyst was a promising catalyst for purification of diesel exhausts.