Sökning: "NH3-SCR"

Visar resultat 6 - 10 av 22 avhandlingar innehållade ordet NH3-SCR.

1. 6. Titania supported vanadium oxide catalysts in the NH3-SCR reaction: Effect of vanadium loading, promoters and aging

   Författare :Alexander Nellessen; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Nb; aging; Ce; infrared spectroscopy; VOx; NH3-SCR; vanadium oxide;

   Sammanfattning : Emissions of nitrogen oxides (NOx) from combustion processes in mobile sources attract significant attention due to their role as a major source of atmospheric contamination, along with health risks and environmental issues. Since combustion processes in heavy-duty vehicles are expected to be used for a foreseeable future, many efforts have been invested in a suitable deNOx technology. LÄS MER

3. 7. Fundamentals of NH3-SCR and SOx chemistry over copper zeolite for the control of NOx and greenhouse gas (N2O) emissions

   Författare :Joonsoo Han; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; DeNOx; Cu SSZ-13; NH3-SCR; N2O; EATS; SO3; ammonium nitrate; SO2;

   Sammanfattning : The release of N2O over Cu-zeolite was investigated due to the critical contribution it makes to the atmosphere as one of the greenhouse gases (GHGs). An exhaust after-treatment system (EATS) for heavy-duty vehicles that uses Cu/SSZ-13 as the selective catalyst reduction (SCR) catalyst experiences not only a variety of flow, temperature and chemical conditions but is also exposed to various resulting contaminants. LÄS MER

4. 8. NH3-SCR chemistry for NOx abatement: Influence of zeolite support on N2O formation & phosphorus species addition

   Författare :Joonsoo Han; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Copper; NH3 SCR chemistry; Zeolite topology; N2O; Phosphorus poisoning;

   Sammanfattning : Different lattice arrangements of Si, Al, and O atoms result in a variety of pore dimensions and zeolite channel network systems, giving rise to different physicochemical environments inside the catalyst cage. The objective of the thesis work was to understand the influence of zeolite topology on NH3-assisted SCR chemistry over CHA, MFI, and BEA frameworks, on the formation of N2O and the addition of phosphorus species to attain fundamental insight into NOx emission control. LÄS MER

5. 9. On the reaction mechanism for selective catalytic reduction of NOx by NH3 over Cu-zeolites

   Författare :Lin Chen; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; DFT; O2-activation; Cu-SSZ-13; NH3-SCR; Cu-CHA; Al-distribution;

   Sammanfattning : Nitrogen oxides (NOx) are major pollutants from combustion processes, being corrosive and hazardous to human health. The main technology for exhaust aftertreatment of NOx emitted from diesel engines is selective catalytic reduction with ammonia as reducing agent (NH3-SCR). LÄS MER

7. 10. Reactions on nanostructured and microporous surfaces

   Författare :Anna Clemens; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Cu-CHA; XRD; solid-state ion-exchange; materials characterisation; electron microscopy; NH3-SCR; zeolites; catalysis; nanostructured graphite; Water ice; DRIFTS; XPS; NOx reduction; Cu-SSZ-13; temperature programmed desorption; ultra-high vacuum; intercalation; UV-Vis spectroscopy;

   Sammanfattning : Interactions between surfaces and molecules play a central role in various fields where catalysis is one example. In order to understand different surface processes, physicochemical characterisation of the surface materials and molecules is required. LÄS MER