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Oulu, Finland

Karkkainen M.,University of Oulu | Kolli T.,University of Oulu | Honkanen M.,Tampere University of Technology | Heikkinen O.,Aalto University | And 6 more authors.
Topics in Catalysis

Phosphorus is found to have a deactivating effect on the catalytic activity of the studied natural-gas-oxidation catalyst. Accelerated laboratory-scale phosphorus treatment was done to the PtPd/Al2O3 natural gas oxidation catalyst. The effect of phosphorus after low (0.065 M) and high (0.13 M) phosphorus concentration treatments was studied by using an inductively coupled plasma optical emission spectroscopy, N2 physisorption, X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. In addition, the behavior of the catalyst was studied by a Gasmet FT-IR gas analyzer. Based on the received results it can be concluded that phosphorus was adsorbed on the surface by chemical bonds forming phosphates (PO4). In addition, the partial transformation of PdO to Pd was observed. Due to the phosphorus adsorption both the CO and CH4 oxidation activities were lower after the phosphorus treatments compared with the fresh catalyst. © 2016, Springer Science+Business Media New York. Source

Valiheikki A.,University of Oulu | Petallidou K.C.,University of Cyprus | Kalamaras C.M.,University of Cyprus | Kolli T.,University of Oulu | And 4 more authors.
Applied Catalysis B: Environmental

The selective catalytic reduction of NOx by H2 (H2-SCR) under strongly oxidizing conditions (520ppm NOx/1% H2/5% O2/10% CO2/He; NO:NO2-4:1-9:1) in the 150-600°C range has been studied over 3wt-% W-promoted CeO2-ZrO2 solids (85wt-% CeO2-15wt-% ZrO2 (CeZr), and 17wt-% CeO2-83wt-% Zr (ZrCe) synthesised by a proprietary method) for the first time. The highest NOx conversion (XNOx=54%) was obtained on the W-ZrCe (Zr-rich) solid at 300°C (GHSV of 51,000h-1), whereas N2-selectivity was in the 77-92%-range over both W-ZrCe (Zr-rich) and W-CeZr (Ce-rich) catalysts. Significantly higher integral specific rates (RNO, μmolNOm-2min-1) were estimated on the W-ZrCe (Zr-rich) catalyst compared to the W-CeZr (Ce-rich) one in the 250-350°C range. The formation of adsorbed NOx under 0.1% NO/10% O2/He gas treatment at 25°C followed by H2/O2-TPSR experiments revealed that at least two different kinds of active NOx of low concentration (4-7μmolg-1) were formed on both catalysts, whereas other inactive (spectator) NOx species formed were of larger concentration (>160μmolg-1). UV-vis/DRS studies revealed that deposition of 3wt-% W on ZrCe (Zr-rich) mixed metal oxide following calcination at 600°C resulted in the formation of both polymeric WOx and WO3 clusters, whereas on CeZr (Ce-rich) only the latter phase (W6+) was seen. Large differences in the concentration (μmolm-2) and strength of surface acid sites between the W-CeZr and W-ZrCe solids were revealed after performing NH3-TPD and NH3-DRIFTS. These results were found to correlate with the specific H2-SCR rate (μmolm-2min) obtained for the two solids. In particular, the surface acid sites on W-ZrCe and W-CeZr solids were found to be 5.96 and 2.76μmolm-2, respectively, whereas the specific reaction rate was 0.14 and 0.046μmolm-2min at 300 and 250°C, at which maximum rates were observed, respectively. © 2014 Elsevier B.V. Source

Honkanen M.,Tampere University of Technology | Karkkainen M.,University of Oulu | Kolli T.,University of Oulu | Heikkinen O.,Aalto University | And 9 more authors.
Applied Catalysis B: Environmental

Accelerated deactivation, caused by thermal aging (TA) and/or sulfur+water poisoning (SW), of the PtPd/γ-Al2O3 natural-gas oxidation catalyst was studied. Thermal aging and poisoning treatments were performed separately and with varied combinations and comprehensive characterization of the catalyst was carried out after each step. The fresh catalyst has small, oxidized PtPd particles (<5nm) uniformly distributed in the γ-alumina washcoat. After the SW-treatment, a small amount of bulk aluminum sulfate was observed near the slightly grown noble metal particles. During the thermal aging, γ-alumina changed to δ-/θ- and α-alumina. In addition, total decomposition of oxidized Pt and partly decomposition of oxidized Pd occurred resulting in the formation of the grown noble metal particles with a bimetallic PtPd core and a polycrystalline PdO shell. Also few, small (~5nm) bimetallic PtPd particles were still detected. In the TA+SW-treated catalyst with grown noble metal particles, a small amount of bulk aluminum sulfate was detected and it was randomly distributed over the noble metal particles and washcoat. The activity in the terms of methane conversion over the TA-, SW-, and SW+TA-treated catalysts was similar but it was decreased compared to the fresh catalyst. The activity of the TA+SW-treated catalyst was drastically decreased compared to the fresh catalyst due to significant morphological changes and aluminum sulfate formation. © 2015 Elsevier B.V. Source

Agency: Cordis | Branch: H2020 | Program: IA | Phase: GV-7-2014 | Award Amount: 27.80M | Year: 2015

The overall objective of HDGAS is to provide breakthroughs in LNG vehicle fuel systems, natural gas and dual fuel engine technologies as well as aftertreatment systems. The developed components and technologies will be integrated in up to three demonstration vehicles that are representative for long haul heavy duty vehicles in the 40 ton ranges. The demonstration vehicles will: a) comply with the Euro VI emission regulations b) meet at minimum 10% CO2 reduction compared to state of the art technology c) show a range before fueling of at least 800 km on natural gas; d) be competitive in terms of performance, engine life, cost of ownership, safety and comfort to 2013 best in class vehicles. Three HDGAS engine concepts/technology routes will be developed: - A low pressure direct injection spark ignited engine with a highly efficient EGR system, variable valve timing comprising a corona ignition system. With this engine a stoichiometric as well as a lean burn combustion approach will be developed. Target is to achieve 10% higher fuel-efficiency compared with state of the art technology - A low pressure port injected dual fuel engine, a combination of diffusive and Partially Premixed Compression Ignition (PPCI) combustion, variable lambda close loop control and active catalyst management. Target is to achieve > 10% GHG emissions reduction compared with state of the art technology at a Euro VI emission level, with peak substitution rates that are > 80%; - A high pressure gas direct injection diesel pilot ignition gas engine, that is based on a novel injector technology with a substitution rate > 90% of the diesel fuel. Target is to achieve same equivalent fuel consumption (< 215g/kWh) and 20% lower GHG emissions than the corresponding diesel engine. HDGAS will develop all key technologies up to TRL6 and TRL7 and HDGAS will also prepare a plan for a credible path to deliver the innovations to the market.

Dinex Ecocat Oy | Date: 2013-02-14

A catalyst coating for use in a hydrolysis catalyst (H-catalyst) for the reduction of nitrogen oxides, a manufacturing method for such a coating, a catalyst structure and its use are described. The H-catalyst includes alkaline compounds, which are capable of adsorbing HNCO and/or nitrogen oxides and which include alkali and alkaline earth metals, lanthanum and/or yttrium and/or hafnium and/or prasedium and/or gallium, and/or zirconium for promoting reduction, such as for promoting the hydrolysis of urea and the formation of ammonia and/or the selective reduction of nitrogen oxides.

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