|
KMID : 1024520110200020251
|
|
Journal of the Environmental Sciences
2011 Volume.20 No. 2 p.251 ~ p.260
|
|
|
CO and C3H8 Oxidations over Supported Co3O4, Pt and Co3O4-Pt Catalysts: Effect on Their Preparation Methods and Supports, and Catalyst Deactivation
|
|
Kim Moon-Hyeon
Kim Dong-Woo
Ham Sung-Won
|
|
|
Abstract
|
|
|
|
TiO2- and SiO2-supported Co3O4, Pt and Co3O4-Pt catalysts have been studied for CO and C3H8 oxidations at temperatures less than 250oC which is a lower limit of light-off temperatures to oxidize them during emission test cycles of gasoline-fueled automotives with TWCs (three-way catalytic converters) consisting mainly of Pt, Pd and Rh. All the catalysts after appropriate activation such as calcination at 350oC and reduction at 400oC exhibited significant dependence on both their preparation techniques and supports upon CO oxidation at chosen temperatures. A Pt/TiO2 catalyst prepared by using an ion-exchange method (IE) has much better activity for such CO oxidation because of smaller Pt nanoparticles, compared to a supported Pt obtained via an incipient wetness (IW). Supported Co3O4-only catalysts are very active for CO oxidation even at 100oC, but the use of TiO2 as a support and the IW technique give the best performances. These effects on supports and preparation methods were indicated for Co3O4-Pt catalysts. Based on activity profiles of CO oxidation at 100oC over a physical mixture of supported Pt and Co3O4 after activation under different conditions, and typical light-off temperatures of CO and unburned hydrocarbons in common TWCs as tested for C3H8 oxidation at 250oC with a Pt-exchanged SiO2 catalyst, this study may offer an useful approach to substitute Co3O4 for a part of platinum group metals, particularly Pt, thereby lowering the usage of the precious metals.
|
|
|
KEYWORD
|
|
|
CO and C3H8 oxidations, Co3O4, Preparation method and support effects, Substitute for platinum group metals, TWCs
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
|
|