Search for dissertations about: "lean NOx reduction"

Showing result 6 - 10 of 54 swedish dissertations containing the words lean NOx reduction.

  2. 6. Lean NOx reduction with methanol over supported silver catalysts

    Author : Marika Männikkö; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; lean NOx reduction; SCR; silver species; silver alumina; methanol; hydrogen; silver ZSM-5;

    Abstract : The oxygen rich and relatively cold exhaust gases from fuel-efficient combustion engines bring challenges for the reductive aftertreatment of NOx. In this context selective catalytic reduction over silver/alumina has shown positive results, especially with oxygenated reducing agents. READ MORE

  4. 7. Studies on continuous lean NOx reduction with hydrocarbons over dual pore size zeolite catalysts

    Author : Thomas Holma; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; lean exhaust; MOR; dual pore system; FER; NOx reduction; HC-SCR; ZSM-5; diesel exhaust; zeolites;

    Abstract : .... READ MORE

  5. 8. Experimental Studies of NOx Catalysts; Storage, Reduction and Sulphur Deactivation

    Author : Annika Amberntsson; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; barium oxide; NOx storage; platinum; rhodium; sulphur poisoning; NOx reduction;

    Abstract : The aim of this thesis work was to investigate how different gaseous compounds, present in an automotive exhaust from lean-tuned combustion, interact with so-called NOx storage catalysts containing Al2O3 as a support, BaO as the NOx storage compound and noble metals to provide oxidation and reduction functions. The investigations included model sample preparations, flow reactor studies with various gas mixtures and spectroscopic experiments (FTIR and XPS). READ MORE

  6. 9. Studies on Lean NOx Reduction with Ammonia. Catalysts and Sensors

    Author : Mikaela Wallin; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; catalysis; Pt SiO2; NOx reduction; gas sensor; DFT; SCR; H-ZSM-5; in situ FTIR; LCAO; DRIFT; high throughput screening; transient ammonia supply; ammonia; microemulsion; perovskite;

    Abstract : Selective catalytic reduction of NOx with ammonia, NH3-SCR, is a promising technique to reduce NOx under lean conditions, e.g. in diesel engine exhausts. The main objective of this thesis was to gain further understanding of key parameters affecting the performance of catalysts and sensors for NH3-SCR. READ MORE

  7. 10. Lean NOx reduction over silver-alumina catalysts - Aspects on synthesis, structure and activity

    Author : Hannes Kannisto; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; freeze-drying; HC-SCR; DRIFTS.; aromatic hydrocarbons; silver-alumina; Lean NOx reduction; selective catalytic reduction; sol-gel; characterization; catalyst preparation; kinetic modeling;

    Abstract : The aim of this thesis is to increase the understanding of how to design highly active silver-alumina catalysts for selective catalytic reduction of NOx with hydrocarbons (HC-SCR) in oxygen excess at low temperatures (150-250 °C). Silver-alumina catalysts have been prepared using different methods, including a new unique preparation method developed during the thesis project. READ MORE