Sökning: "Catalyst"

Visar resultat 6 - 10 av 782 avhandlingar innehållade ordet Catalyst.

  1. 6. Fundamental deactivation mechanisms of Fe-BEA as NH3-SCR catalyst - Experimental studies and kinetic modeling

    Författare :Soran Shwan; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Dealumination; Hydrothermal treatment; Catalyst deactivation; NH3-SCR; Kinetic ageing model; Catalyst ageing; Fe-BEA;

    Sammanfattning : Due to globalization and an increasing transport sector the interest for more fuel efficient combustion engines operating under lean conditions has increased. The products formed during the burning process in internal combustion engines are major contributants to global air pollution, where carbon monoxide (CO), hydrocarbons (HC) and nitrogen oxides (NOX) are the major toxic components regulated in many countries. LÄS MER

  3. 7. Fluid Catalytic Cracking Catalyst Demetallization and Reactivation, Modeling of Catalytic Cracking, and Use of Microwaves to Heat Fluid Beds

    Författare :Frank J. Elvin; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; pilot plant; nickel and vanadium deposition; catalyst; reactivation; demetallization; catalytic cracking; and microwave heating; MAT; fluid bed;

    Sammanfattning : The fluid catalytic cracking unit (FCCU), the major conversion unit in an oil refinery, uses a silica-alumina zeolite catalyst to convert heavy hydrocarbons to light hydrocarbons. A small fraction of the catalyst must be continually replaced with fresh catalyst to maintain activity. LÄS MER

  4. 8. Asymmetric Formation and Isomerization of Three-Membered Rings : Catalyst Development and Evaluation

    Författare :Sophie Bertilsson; Tobias Rein; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Chemistry; allylic alcohol; α-amino acid derivative; aza-Diels-Alder reaction; aziridination; cyclopropanation; desymmetrization; epoxide rearrangement; kinetic resolution; lithium amide; rhodium-carboxylate; Kemi; Chemistry; Kemi; organisk kemi; Organic Chemistry;

    Sammanfattning : Enantiopure α-amino acid derivatives were prepared using a protocol which allows for highly controlled regio- and chemoselectivity in the hydrogenation/ hydrogenolysis of aza-Diels-Alder adducts. One of the resulting α-amino esters, (1S,3R,4R)-2-azabicyclo[2.2.1]heptane-3-carboxylic acid ethyl ester, was utilized further as a catalyst precursor. LÄS MER

  5. 9. In situ Studies of Platinum Catalyst Sintering

    Författare :Pooya Tabib Zadeh Adibi; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nanoparticle sintering; indirect nanoplasmonic sensing; operando spectroscopy; transmission electron microscopy; platinum; catalyst deactivation; sintering kinetics;

    Sammanfattning : The damaging effect of pollutants from combustion engine exhaust on human health and environment is well recognized. Since the 70s, the three-way catalytic converter (TWC) has substantially improved the urban air quality by simultaneous conversion of CO, NOx and unburned hydrocarbons to O2, N2 and H2O. LÄS MER

  7. 10. Studies of catalyst sintering during operating conditions

    Författare :Pooya Tabib Zadeh Adibi; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; nanoparticle sintering; operando spectroscopy; catalyst deactivation; indirect nanoplasmonic sensing; platinum; sintering kinetics;

    Sammanfattning : The damaging effect of pollutants from exhaust gas of combustion engines on the human health and the environment is well recognized. Since the 70s, the three-way catalytic converter (TWC) has substantially improved the urban air quality by simultaneous conversion of CO, NOx and unburned hydrocarbons to O2 , N2 , CO2 and H2O. LÄS MER