Spectroscopic Studies on ZrO2 Modified with MoO3 and Activity for Acid Catalysis

Bulletin of the Korean chemical society

Eun Woo Chun¹  Jong Rack Sohn¹  Young Il Pae¹ 

关键词: MoO3/ZrO2 catalyst;    Spectroscopic characterization;    Acid catalysis;    2-Propanol dehydration;    Cumene dealkylation;   

DOI  :  

学科分类：化学（综合）

来源: Korean Chemical Society

【 摘 要 】

Zirconia modified with MoO₃ was prepared by impregnation of powdered Zr(OH)₄ with ammonium heptamolybdate aqueous solution followed by calcining in air at high temperature. Spectroscopic studies on prepared catalysts were performed by using FTIR, Raman, XRD, and DSC and by measuring surface area. Upon the addition of molybdenum oxide to zirconia up to 15 wt%, the specific surface area increased in proportion to the molybdate oxide content, while acidity measured by irreversible chemisorption of ammonia exhibited a maximum value at 3 wt% of MoO₃. Since the ZrO₂ stabilizes the molybdenum oxide species, for the samples equal to or less than 30 wt%, molybdenum oxide was well dispersed on the surface of zirconia and no phase of crystalline MoO₃ was observed at any calcination temperature above 400 �?. The catalytic activities for cumene dealkylation were roughly correlated with the acidity of catalysts measured by ammonia chemisorption method, while the catalytic activities for 2-propanol dehydration were not correlated with the acidity because weak acid sites are necessary for the reaction.

【 授权许可】

Unknown