3D PRINTED COMPOSITE ZEOLITE CATALYSTS FOR THE SCR OF NOx

NOx removal from emission of diesel engines by Selective Catalytic Reduction (SCR) requires catalysts which, in addition to high catalytic performances, must have good thermal and mechanical properties. They should operate in a wide temperature window, to cope with cold start phases as well as high temperature regeneration treatments for the upstream particulate filters. Zeolites, such as ZSM-5, are very active in a wide temperature range when exchanged with copper or iron. Unfortunately, ZSM-5 cannot be produced in bulky structured monolith reactor because of their scarce adhesion properties; therefore, they are typically applied at limited loadings as a washcoat on preformed (inert) honeycomb monoliths. In this work, a ZSM-5 (up to 60% by weight) was incorporated in a geopolymer matrix and directly formed as a structured monolith by an additive manufacturing method (Direct Ink Writing).