Structured SiSiC-zeolite ceramic composites for catalytic applications via a support self-transformation technique

摘要

The overall 3-step process for the manufacturing of SiSiC-zeolite structured cellular composites was studied.The process consists of a 2-step procedure for the ceramic monolith fabrication,followed by the functionalisation of the support surface with zeolite coating (3~(rd) step).SiSiC ceramic monoliths were prepared by reactive Liquid Silicon Infiltration (LSI) of carbon preforms from corrugated cardboard monoliths.The zeolite coating process consisted of a hydrothermal treatment of the SiSiC carrier in an alkaline solution containing the template and the Al-source,while the Si was provided from the ceramic substrate.MFI-type (ZSM-5) zeolite crystals were directly grown on the ceramic supports via a partial Si dissolution (from the SiSiC matrix) and zeolite crystallisation (support self-transformation).Cellular SiSiC-zeolite monoliths possess bimodal (micro-/macro-) porosity and high mechanical,chemical and thermal stabilities.