Sökning: "Cu-SSZ-13"

Visar resultat 1 - 5 av 7 avhandlingar innehållade ordet Cu-SSZ-13.

1. 1. Deactivation of emission control catalysts for heavy-duty vehicles : Impact of biofuel and lube oil-derived contaminants

   Författare :Sandra Dahlin; Lars Pettersson; Isabella Nova; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NH3-SCR; Cu-SSZ-13; V2O5-WO3 TiO2; catalyst deactivation; diesel oxidation catalyst; sulfur; phosphorus; biodiesel; heavy-duty; emission control; regeneration; alkali metals; NH3-SCR; Cu-SSZ-13; V2O5-WO3 TiO2; katalysatordeaktivering; dieseloxidationskatalysator; svavel; fosfor; biodiesel; tunga dieselmotorer; avgasrening; regenerering; alkalimetaller; Chemical Engineering; Kemiteknik;

   Sammanfattning : Catalytic emission control is used to reduce the negative impact of pollutants from diesel exhausts on our health and on the environment. For a heavy-duty truck, such a system consists of a diesel oxidation catalyst (DOC), a diesel particulate filter (DPF), a selective catalytic reduction (SCR) catalyst, and an ammonia slip catalyst (ASC). LÄS MER

3. 2. Deactivation of SCR catalysts - Impact of sulfur and the use of biofuels

   Författare :Johanna Englund; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Cu-SSZ-13; Cu-CHA; Catalyst deactivation; Activity test; DeNOx; Sulfur; NOx reduction; NH3-SCR; FAME; Emission control; HVO; Vanadia; Biofuel;

   Sammanfattning : In a near future, limits on CO2 emissions from vehicles will be introduced, which requires development of more fuel-efficient engines and most likely a transition towards the use of more biofuels. With the implementation of biofuels several issues could arise, one being the lack of fuel standards for these new type of fuels, leading to higher concentrations of catalyst poisons compared to conventional fossil fuels. LÄS MER

4. 3. 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

5. 4. On the Character of Active Sites in Copper Exchanged Zeolites during NH3-SCR

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

   Sammanfattning : Nitrogen oxides (NOx) are formed during combustion in diesel engines and one current approach to reduce NOx to N2 is selective catalytic reduction with NH3 as reducing agent (NH3-SCR). To acquire both high activity and selectivity, the active site is often atomically dispersed metal atom, so-called single-site catalysts. LÄS MER

7. 5. 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