Sökning: "chemical treatment"
Visar resultat 1 - 5 av 1073 avhandlingar innehållade orden chemical treatment.
1. Metal-exchanged zeolites for NH3-SCR applications - Activity and Deactivation studies
Sammanfattning : Emissions of nitrogen oxides (NOX) formed during the burning process in internal combustion engines is a major contributor to global air pollutions. One effective way to reduce NOX in lean environments, i.e. oxygen excess is selective catalytic reduction with ammonia (NH3-SCR). LÄS MER
2. The adsorption of arsenic oxyacids to iron oxyhydroxide columns : including studies of weakly hydrated ions and molecules in aqueous solution
Sammanfattning : The fundamental side of this project includes determination of ionic radii and plausible hydration numbers for the weakly hydrated alkali metal ions in solution, as well as an investigation of the intramolecular bond lengths of arsenic oxyacid species and orthotelluric acid. Experimental methods such as EXAFS, XANES and LAXS have been used for these purposes, as well as thorough screening for relevant structures in crystal structure databases. LÄS MER
3. Assessing and optimizing biofilter performance in drinking water treatment
Sammanfattning : Biological filtration is a widely used treatment barrier in drinking water treatment plants to ensure the biological stability of treated water in distribution systems. Biofilters remove particulate and dissolved organic matter (DOM) and biodegradable organic matter from water. LÄS MER
4. Complete methane oxidation over alumina and zeolite supported palladium for emission control
Sammanfattning : The use of methane-based fuels, such as natural gas and biogas, gives lower emissions of for instance carbon dioxide (CO2) and particulate matters compared to traditionally used liquid fossil fuels. However, the exhaust gases contain significant levels of unburnt methane (CH4) residuals, which are desirable to minimize since CH4 has a high global warming potential. LÄS MER
5. Recycling of nickel metal hydride (NiMH) batteries; Characterization and recovery of nickel, AB5 alloy and cobalt
Sammanfattning : Nickel metal hydride (NiMH) batteries are used today for applications that can assist in the adaptation toward carbon-neutral energy sources (i.e. hybrid vehicles and smart grids). Recovery of metals such as nickel, cobalt and rare earth elements (REEs) from discarded NiMH batteries is important for economic and/or technological reasons. LÄS MER