Ag-Based Catalysts in Different Supports: Activity for Formaldehyde Oxidation  

作　　者：Rached Ousji Zouhaier Ksibi Abdelhamid Ghorbel Céline Fontaine Rached Ousji;Zouhaier Ksibi;Abdelhamid Ghorbel;Céline Fontaine(Laboratory of Materials Chemistry and Catalysis, Faculty of Sciences of Tunis, University of Tunis El Manar, Tunis, Tunisia;Institute of Chemistry of Poitiers: Materials and Natural Resources (IC2MP), University of Poitiers, Poitiers, France)

机构地区：[1]Laboratory of Materials Chemistry and Catalysis, Faculty of Sciences of Tunis, University of Tunis El Manar, Tunis, Tunisia [2]Institute of Chemistry of Poitiers: Materials and Natural Resources (IC2MP), University of Poitiers, Poitiers, France

出　　处：《Advances in Materials Physics and Chemistry》2022年第8期163-176,共14页材料物理与化学进展（英文）

摘　　要：Through the impregnation method, Ag catalysts with different support (such as TiO₂ and γ-Al₂O₃) were prepared and then tested for catalytic oxidation of formaldehyde (HCHO) at low temperatures. The Ag/TiO₂ catalyst exhibited strong catalytic performance, converting HCHO to CO₂ and H₂O at around 95°C. However, the Ag/Al₂O₃ catalysts showed much lower activity and reached 100% conversion at 125°C. The Ag-based catalysts were next characterized by several methods (XRD, TEM, FT-R, BET and H₂-TPR). Results of characterization revealed that support dramatically impacts the size and dispersion of Ag particles. The XRD analysis showed the existence of different peaks of the silver on the surface of Al₂O₃ in the contrast with TiO₂ no specific peaks exist. Therefore, the size of the Ag particles and their dispersion are the most important factors that affect their catalytic performance for formaldehyde oxidation. In terms of catalytic performance for HCHO oxidation, the Ag/TiO₂catalyst possesses the best Ag dispersion, as well as the smallest Ag particle size.Through the impregnation method, Ag catalysts with different support (such as TiO₂ and γ-Al₂O₃) were prepared and then tested for catalytic oxidation of formaldehyde (HCHO) at low temperatures. The Ag/TiO₂ catalyst exhibited strong catalytic performance, converting HCHO to CO₂ and H₂O at around 95°C. However, the Ag/Al₂O₃ catalysts showed much lower activity and reached 100% conversion at 125°C. The Ag-based catalysts were next characterized by several methods (XRD, TEM, FT-R, BET and H₂-TPR). Results of characterization revealed that support dramatically impacts the size and dispersion of Ag particles. The XRD analysis showed the existence of different peaks of the silver on the surface of Al₂O₃ in the contrast with TiO₂ no specific peaks exist. Therefore, the size of the Ag particles and their dispersion are the most important factors that affect their catalytic performance for formaldehyde oxidation. In terms of catalytic performance for HCHO oxidation, the Ag/TiO₂catalyst possesses the best Ag dispersion, as well as the smallest Ag particle size.

关 键 词：Formaldehyde Oxidation TiO₂ Al₂O₃ Silver (Ag) IMPREGNATION SOL-GEL 

分 类 号：O64[理学—物理化学]