Study of the reduction of nitrogen oxides with CO and H2 on Pt-Mo catalysts in the oxidizing range
The redn. of NOx with CO and H2 on Pt-Mo/a-Al2O3 catalysts as an alternative for Pt-Rh catalysts was studied for exhaust gas purifn. in lean-mixed engines in oxidizing range. The NOx content has a significant influence on the catalyst activity. The H2/O2 reaction is complete at .apprx.70 Deg in absence of NOx. A NOx content of 0.1% results in an increase of the NOx decompn. reaching a max. of 80% at .apprx.90-120 Deg and a decrease at higher temps. (16% at .apprx.200 Deg). NOx was not reduced by CO at the given conditions and CO inhibited the NO/H2 and the O2/H2 reaction. The activities of the Pt-Mo-catalysts were compared with other 3-way catalysts contg. 0.2% Pt, 0.7% Mo, and 0.1% Cu, Ni, or Co. A significant increase of the NOx reaction rate was reached by the Co-contg. catalyst at presence of 0.3-0.6% CO in the exhaust gas. [on SciFinder (R)]
1998
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7
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886
CAN 129:126381 59-3 Air Pollution and Industrial Hygiene Inst. Genie Chimique,ETH Lausanne,Lausanne,Switz. Journal 0009-286X written in German. 7439-98-7 (Molybdenum); 7440-06-4 (Platinum) Role: CAT (Catalyst use), USES (Uses) (redn. of nitrogen oxides in exhaust gases with CO and H2 on Pt-Mo catalysts in oxidizing range); 630-08-0 (Carbon monoxide); 1333-74-0 (Hydrogen); 7782-44-7 (Oxygen) Role: PEP (Physical, engineering or chemical process), RCT (Reactant), PROC (Process), RACT (Reactant or reagent) (redn. of nitrogen oxides in exhaust gases with CO and H2 on Pt-Mo catalysts in oxidizing range); 11104-93-1 (Nitrogen oxide) Role: REM (Removal or disposal), PROC (Process) (redn. of nitrogen oxides in exhaust gases with CO and H2 on Pt-Mo catalysts in oxidizing range); 1344-28-1 (a-Alumina) Role: CAT (Catalyst use), USES (Uses) (redn. of nitrogen oxides in exhaust gases with CO and H2 on Pt-Mo catalysts in oxidizing range on); 7440-02-0 (Nickel); 7440-48-4 (Cobalt); 7440-50-8 (Copper) Role: CAT (Catalyst use), USES (Uses) (redn. of nitrogen oxides in exhaust gases with CO and H2 on Pt-Mo catalysts in oxidizing range with addn. of)
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