Sökning: "alumina active"
Visar resultat 1 - 5 av 44 avhandlingar innehållade orden alumina active.
1. Active sites and influence of reaction conditions on the selective catalytic reduction of NOx over the silver-alumina catalyst
Sammanfattning : Hazardous nitrogen oxides (NOx) are challenging to remove from fuel-efficient excess-oxygen operating engines. A promising solution is selective catalytic reduction (SCR) of NOx, using hydrocarbons (HC-SCR) or ammonia (NH3-SCR) as reducing agent. LÄS MER
2. Surface Studies of Model Systems relevant for Pd and Ag Catalysts
Sammanfattning : This PhD thesis reports on investigations of the atomic scale structure of model catalysts relevant for the catalytic oxidation of CO and methane over Pd, and NOx reduction over silver-alumina, important reactions in automotive catalysts. By using complementary experimental techniques such as X-ray Photoelectron Spectroscopy, High Pressure X-ray Photoelectron Spectroscopy, Surface X-ray Diffraction, Low Energy Electron Diffraction, Infrared Spectroscopy, and Scanning Tunneling Microscopy, combined with theoretical calculations, the work presented in this thesis aims at an atomistic characterization of the active sites for silver-alumina and Pd model catalysts which may help to the design of new and improved catalysts. LÄS MER
3. Sintering of nickel catalysts in the presence of NH3/H2
Sammanfattning : Supported metal catalysts are used in many important industrial processes, where amination of alcohols is one example. The exposure of the supported metal catalyst to reaction conditions results usually to a decrease in catalytic activity, by for instance thermal degradation. LÄS MER
4. Low-Temperature Oxidation of CO and Volatile Organic Compounds over Supported Platinum Catalysts
Sammanfattning : The catalytic oxidation of carbon monoxide (CO) and volatile organic compounds (VOC) is important for the reduction of harmful emissions from both vehicles and from stationary sources. Both these applications suffer from poor catalytic efficiency at lower temperatures. LÄS MER
5. Catalytic Incineration of CO and VOC Emissions over Supported Metal Oxide Catalysts
Sammanfattning : Catalytic incineration is one of the methods to reduce the emissions of CO and VOCs. Low operation temperature and low catalyst cost are essential parameters for catalytic incinerators. Pt/Al2O3 catalysts are frequently used today, but the cheaper metal oxide catalysts can be very competitive if comparable overall activity is obtained. LÄS MER