Search for dissertations about: "lean NOx trap"

Showing result 1 - 5 of 9 swedish dissertations containing the words lean NOx trap.

2. 1. NOx reduction with dimethyl ether in lean exhaust

   Author : Sara U Erkfeldt; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NOx storage; Dimethyl ether; ether; hydrocarbon-SCR; lean NOx reduction; alcohol; Cu-ZSM-5; lean NOx trap; alkane; alternative fuel;

   Abstract : There is a growing concern worldwide about the increase in anthropogenic greenhouse gas emissions, particularly carbon dioxide (CO2) from the combustion of fossil fuels. Vehicles with internal combustion engines contribute significantly to these emissions, which has led to an increased demand for engines running on alternative (non-fossil) fuels. READ MORE

4. 2. Exhaust aftertreatment under lean conditions, regenerable SOx traps and NOx reduction catalysts

   Author : Lisa Kylhammar; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Heterogenous catalysis; Selective catalytic reduction; HC-SCR; Sulfur storage; SOx trap; Spectroscopy; Lean exhausts; NOx; Ag Al2O3; DRIFT; XPS;

   Abstract : The aim of this thesis was to investigate i) potential materials for regenerable SOx traps and ii) the influence of silver distribution within Ag/Al2O3 catalysts on the selective reduction of NOx by hydrocarbons (HC-SCR). Both areas are highly relevant for present and future vehicle aftertreatment technologies for lean exhausts. READ MORE

5. 3. Aging effects on commercial lean NOx trap catalysts

   Author : Jesus De Abreu Goes; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; aging; thermal degradation; sulfur poisoning; characterization; commercial lean NOx traps; NOx storage and reduction;

   Abstract : As a countermeasure to global warming, vehicles with low carbon emissions are being investigated by promoting lean-burn engines and high combustion efficiencies. However, one limitation to the increasing use of these engines is the need to develop corresponding catalytic systems for controlling the nitrogen oxide (NOx) emissions in their lean exhaust. READ MORE

6. 4. NOx Storage and Reduction Catalysts. Reduction with Hydrogen and the Influence of Water and Carbon Dioxide

   Author : Anna Maria Lindholm; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NSR catalyst; Pt Ba Al; H2O; CO2; Pt Al; NOx reduction; H2; NH3 formation; NOx storage; Lean NOx Trap; N2O formation; kinetic modeling; Pt Si;

   Abstract : Environmental concern has increased over the past several years and resulted in stringent emission legislation on NOx, CO, and hydrocarbon emissions from automobile exhausts. Moreover, the demands to improve the fuel efficiency of engines and to lower the CO2 emissions have increased, and a way to meet this is by using lean burn engines which operate with oxygen excess. READ MORE

7. 5. Studies of a Heavy-Duty Diesel Aftertreatment System Based on the NOX Storage and Reduction Technology

   Author : Klaus Papadakis; Avdelningen för kemiteknik; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fuel penalty; injection parameters; DoE; design of experiments; exhaust; diesel engine; NO oxidation; simulation; modelling; oxidation catalyst; NOX trap; NOX storage and reduction; NSR; Kemiteknik och kemisk teknologi; Chemical technology and engineering; dosing strategy; system optimisation;

   Abstract : The legislative limits for NOX emissions in the exhaust gas from heavy-duty diesel engines will be decreased in the European Union from today 3.5 g/kWh (Euro IV) to 2.0 g/kWh in 2008 (Euro V). In the USA and Japan a similar trend can be seen. READ MORE