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- Dahlin, Sandra, et al.
(författare)
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Chemical aging of Cu-SSZ-13 SCR catalysts for heavy-duty vehicles –Influence of sulfur dioxide
- 2018
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Ingår i: Catalysis Today. - Amsterdam : Elsevier. - 0920-5861 .- 1873-4308. ; 320, s. 72-83
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Tidskriftsartikel (refereegranskat)abstract
- Selective catalytic reduction of nitrogen oxides is an efficient technique for emission abatement in heavy-dutyvehicles. Cu-SSZ-13 SCR catalysts are more active than vanadium-based catalysts at low temperatures, but aremore sensitive to deactivation by sulfur. Consequently, there is a need to study poisoning by sulfur for thiscatalyst material. This experimental investigation focuses on the effect of sulfur on the low-temperature per-formance of Cu-SSZ-13 SCR catalysts. The effect of sulfur exposure temperature, and the influence of the NO 2 /NO x ratio, are considered and two different regeneration temperatures are compared. In addition, catalystsamples from an engine-aged catalyst are evaluated. The SO 2 exposure temperature is shown to have an im-portant impact on the deactivation of the Cu-SSZ-13 catalyst. The lowest sulfur exposure temperature (220 °C)results in the most severe deactivation, while the highest temperature during sulfur exposure (400 °C) results inthe lowest degree of deactivation. This was found to be related to the amount of sulfur on the catalyst.Additionally, SO 2 exposure was shown to decrease the N 2 O selectivity. The engine-aged catalyst has a decreasedperformance in terms of both decreased activity and increased N 2 O selectivity. For this catalyst, impurities fromfuel and engine-oil can play a role in the deactivation. Different deactivation mechanisms are seen for the lab-and engine-aged catalysts.
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| 2. |
- Granestrand, Jonas, 1988-, et al.
(författare)
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Catalytic aftertreatment systems for trucks fueled by biofuels – aspects on the impact of fuel quality on catalyst deactivation
- 2018
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Ingår i: RSC Catalysis. - London : Royal Society of Chemistry. - 0140-0568 .- 1465-1920. ; 30, s. 64-145, s. 64-145
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Tidskriftsartikel (refereegranskat)abstract
- The issue of sustainable energy supply is a global problem for pursuing future endeavours in the energy area. In countries such as China and India there is a tremendous growth at the moment, which is envisaged by an ever growing demand for vehicles. Hence, one of the grand challenges of society is to meet the demands for sustainable and environmentally-friendly technologies in the transport sector. One way to tackle the problem of growing concentrations of carbon dioxide, which is believed to contribute to global warming, is the use of biofuels. It is becoming more and more evident that global warming is partly due to increasing anthropogenic carbon dioxide emissions. An important contribution to these emissions is the use of fossil fuels in the transport sector. Hence, more efficient engines and an increased use of biofuels would be a step in the right direction. Although new propulsion systems are emerging, such as hybrid power-trains and fuel cell systems, analysis shows that combustion systems with excess oxygen, such as the diesel engine, will be the most important engine concept for the next 20 years. In this paper we will identify the specific challenges related to the production and use of biofuels in heavy-duty trucks and how they influence the catalytic units in the emission after-treatment system in the truck. Biofuels, such as biodiesel, contain potential poisons for the vehicle exhaust after-treatment, such as potassium, sodium, magnesium, phosphorus, zinc, sulfur and other compounds.
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