Search for dissertations about: "temperature programmed desorption"

Showing result 11 - 15 of 33 swedish dissertations containing the words temperature programmed desorption.

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

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

    Abstract : 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). READ MORE

  2. 12. Kinetic Studies of NO Oxidation and Reduction over Silver-Alumina Catalyst

    Author : Muhammad Mufti Azis; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TPD; Silver Alumina; HC-SCR; Kinetic modeling; Hydrogen effect; NOx reduction; NO oxidation.;

    Abstract : In line with growing concerns to manufacture more environmentally friendly vehicles, the use of internal combustion engines operating with oxygen excess or so called lean-burn engines will continue to be increasingly used. For lean-burn operation, reduction of NOx (NO+NO2) emissions is a major challenge and it is therefore urgently required to develop efficient and reliable NOx reduction aftertreatment systems for a wide variety of lean-burn or diesel engines. READ MORE

  3. 13. Oxygen Storage Chemistry of Nanoceria

    Author : Dou Du; Kersti Hermansson; Peter Broqvist; Pavlin D. Mitev; Joachim Paier; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Nanoceria; Density Functional Theory; Hybrid Functional; Oxygen Storage Capacity.; Kemi med inriktning mot materialkemi; Chemistry with specialization in Materials Chemistry;

    Abstract : The versatile redox chemistry of ceria (CeO2) originates from its Ce4f electron, which plays the key role in changing the oxidation state of Ce between +IV and +III. Ceria is, among other things, a material that can act as a powerful oxygen buffer with a high oxygen storage capacity (OSC). READ MORE

  4. 14. NH3-SCR over Cu-zeolite catalysts: activity and deactivation studies

    Author : Kurnia Wijayanti; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Cu‑SAPO-34; internal mass transfer limitation; NH3‑SCR; Cu-zeolite; hydrothermal aging; SO2 poisoning; Cu‑Beta; Cu‑SSZ‑13;

    Abstract : NOx emission is one of the major contributors to air pollution especially in the urban environment. The most frequently applied technique to reduce NOx from diesel engine is to employ ammonia selective catalytic reduction (NH3-SCR) using Cu‑zeolite as the catalyst. READ MORE

  5. 15. Gas Adsorption and Permeation in MFI Zeolites and Membranes

    Author : Sang Wirawan; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; composite membranes; TPD; MFI zeolites; WGS membrane reactor; adsorption; FTIR spectra;

    Abstract : The single and multi component gas adsorption behavior on silicalite-1 and cation exchanged MZSM-5 zeolites (M = H, Na, and Ba) were investigated by a step change response method. Temperature programmed desorption (TPD) and in-situ fourier transform infrared (FTIR) spectroscopy were also performed to study the type of adsorbed species and their thermal stabilities. READ MORE