Influence of alumina binders on adhesion and cohesion during preparation of Cu‐SAPO‐34/monolith catalysts

• Published in: International journal of applied ceramic technology 2018-11, Vol.15 (6), p.1490-1501
• Main Authors: Kong, Xiangli, Qiu, Minghui, Wang, Anran, Yang, Lu, Zhou, Rongfei, Fan, Yiqun, Kong, Deshuang, Gu, Changjun
• Format: Article
• Language: English
• Subjects: Adhesive strength; Adhesives; adhesives/adhesion; Alumina; Aluminum oxide; binders/binding; Bonding strength; Catalysis; Catalysts; catalysts/catalysis; Catalytic activity; Ceramic coatings; Ceramic honeycombs; Cohesion; Copper; Cordierite; Crystal structure; Densification; Morphology; Nanoparticles; Shrinkage; Substrates; Zeolite monoliths
• ISSN: 1546-542X; 1744-7402
• DOI: 10.1111/ijac.13008

The adhesion and cohesion between the coating layers and the ceramic honeycombs are usually one of the key issues in the preparation of high‐performance zeolite‐based/Monolith catalysts. In this work, we investigate the deposition of high‐efficiency Cu‐SAPO‐34 catalyst on a cordierite monolith with special focus on the impact of alumina binders on the structure, mechanical adhesion and cohesion, and catalytic performance of the monolithic catalyst. Two kinds of alumina nanoparticles, α‐alumina and γ‐alumina, have no significant impacts on the Cu‐SAPO‐34 crystal structure, micropore morphology and catalytic activity. But washcoating experiments showed that the mass loss rate of the coating was less and the loading of the catalyst was higher when α‐alumina was used as the binder. The reason of improving the adhesion and cohesion strength is the suitable thermal shrinkage, the uniform distribution and densification structure of α‐alumina. Furthermore, optimization of the coating formulation with α‐alumina as the binder has been performed. Finally, the catalyst prepared under the optimal conditions was tested by SCR and a maximum conversion rate of 97.4% was obtained. It was concluded that the use of the washcoating method with α‐alumina does not affect catalytic performance while it increases bonding strength between substrate and catalysts.