Tungstated zirconia nanocatalysts
A new type of solid acid catalyst, which promises better catalytic performance than conventionally prepared supported metal oxides due to its precisely synthesized nanostructure has been described. The catalyst is nanoparticulate in form and is comprised of monolayers of tungstated zirconia of the formula, WOxZryO4-2y made by impregnating a support with zirconium and tungsten. The support catalyst is further characterized in having a tugsten monolayer between greater than 0001 W/nm2 to about 30 W/nm2.
1. A method of making a catalyst comprising impregnating a substrate with a W precursor and a Zr precursor to form an impregnated support, and calcining the impregnated support to generate a WO x ZrO 2 nanoparticle catalyst, and wherein said Zr precursor is zirconium tert-butoxide, Zr[OC(CH 3 ) 3 ] 4 .
2. A method of making a catalyst comprising impregnating a substrate with a W precursor and a Zr precursor to form an impregnated support, and calcining the impregnated support to generate a WO x ZrO 2 nanoparticle catalyst, and wherein said W precursor is ammonium metatungstate (NH 4 )10W 12 O 41 .5H 2 O.
3. A method of making a catalyst comprising:
impregnating a support with zirconium oxide to form a Zr-impregnated support,
further impregnating the Zr-impregnated support with tungsten oxide to form a ZrW-impregnated support, and
calcining the ZrW-impregnated support, thereby providing a catalyst composition comprising WO x ZrO 2 nanoparticles,
wherein said support consists of WO x /SiO 2 , WO x /Al 2 O 3 , or WO x /(SiO 2 —Al 2 O 3 ).