Documents disponibles écrits par cet auteur

Appraisal of a De - NOx system based on H2 for light - duty diesel engine vehicles / Samir Bensaid in Industrial & engineering chemistry research, Vol. 49 N° 21 (Novembre 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 21 (Novembre 2010) . - pp. 10323-10333 Titre : Appraisal of a De - NOx system based on H2 for light - duty diesel engine vehicles Type de document : texte imprimé Auteurs : Samir Bensaid, Auteur ; Edoardo Merlone Borla, Auteur ; Nunzio Russo, Auteur Année de publication : 2011 Article en page(s) : pp. 10323-10333 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Diesel  engine Résumé : The present paper describes a novel, fully integrated after-treatment system based on the use of hydrogen for de-NOx purposes, designed for light-duty diesel engine applications. Hydrogen is generated by an autothermal reformer, placed as a bypass unit of the close-coupled DOC and DPF, and it promotes an NO, reduction in a specific catalytic converter in the under-floor position. The results of the tests on commercial reforming catalysts and on H2-selected catalytic reductions (SCR) perovskite catalysts that were synthesized by our group are presented. The best catalyst, on the basis of TPRe activity tests, was La0.8Sr0.2Fe0.9Pd0.1O3. At a lab-scale, the fuel penalty of the system is around 4% for an NOx to N2 conversion of 60%, under the best operating conditions. T50 is very low (150 °C) compared to other de-NO, strategies. The system was then integrated on board a vehicle, and several testing protocols were performed (NEDC2000 cycle, stationary driving conditions on the roller test bench, and real driving conditions on the road). It has been demonstrated that the system is able to work independently in many driving conditions and that the reforming reaction can be effectively controlled and maintained. The NOx emissions were kept below Euro 6 levels, even though undesired CO and HC secondary emissions were produced. This performance was reached with a fuel penalty of 10%. Although this value is presently too high to envisage direct application on the market, it has been demonstrated that this technology is already fully functional on board a real vehicle, which encourages further refining research activity. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=23447923 [article] Appraisal of a De - NOx system based on H2 for light - duty diesel engine vehicles [texte imprimé] / Samir Bensaid, Auteur ; Edoardo Merlone Borla, Auteur ; Nunzio Russo, Auteur . - 2011 . - pp. 10323-10333. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 21 (Novembre 2010) . - pp. 10323-10333 Mots-clés : Diesel  engine Résumé : The present paper describes a novel, fully integrated after-treatment system based on the use of hydrogen for de-NOx purposes, designed for light-duty diesel engine applications. Hydrogen is generated by an autothermal reformer, placed as a bypass unit of the close-coupled DOC and DPF, and it promotes an NO, reduction in a specific catalytic converter in the under-floor position. The results of the tests on commercial reforming catalysts and on H2-selected catalytic reductions (SCR) perovskite catalysts that were synthesized by our group are presented. The best catalyst, on the basis of TPRe activity tests, was La0.8Sr0.2Fe0.9Pd0.1O3. At a lab-scale, the fuel penalty of the system is around 4% for an NOx to N2 conversion of 60%, under the best operating conditions. T50 is very low (150 °C) compared to other de-NO, strategies. The system was then integrated on board a vehicle, and several testing protocols were performed (NEDC2000 cycle, stationary driving conditions on the roller test bench, and real driving conditions on the road). It has been demonstrated that the system is able to work independently in many driving conditions and that the reforming reaction can be effectively controlled and maintained. The NOx emissions were kept below Euro 6 levels, even though undesired CO and HC secondary emissions were produced. This performance was reached with a fuel penalty of 10%. Although this value is presently too high to envisage direct application on the market, it has been demonstrated that this technology is already fully functional on board a real vehicle, which encourages further refining research activity. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=23447923

Low temperature NH3 selective catalytic reduction of NOx over substituted MnCr2O4 spinel-oxide catalysts / Miguel A. Zamudio in Industrial & engineering chemistry research, Vol. 50 N° 11 (Juin 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 11 (Juin 2011) . - pp 6668–6672 Titre : Low temperature NH3 selective catalytic reduction of NOx over substituted MnCr2O4 spinel-oxide catalysts Type de document : texte imprimé Auteurs : Miguel A. Zamudio, Auteur ; Nunzio Russo, Auteur ; Debora Fino, Auteur Année de publication : 2011 Article en page(s) : pp 6668–6672 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Catalysts  X-ray  diffraction Résumé : The present work describes the development of Mn1–xMxCr2O4 (M = Mg, Ca; x = 0–0.1) substituted spinel catalysts prepared via gel combustion synthesis for the low-temperature selective catalytic reduction (SCR) of NOx with NH3. The catalysts have been characterized by means of X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), field emission scanning electron microscopy (FESEM) and temperature programmed reduction (TPR) analyses, whereas their catalytic activity has been tested in a temperature programmed reaction (TPRe) apparatus over a temperature range of 100–200 °C (W/F = 0.072 g·s·cm–3) in the presence of oxygen. The catalytic activity of alkali earth-metal substituted Mn–Cr spinels is compared with that of the stoichiometric MnCr2O4 in order to assess the effect of the substitutions. All the spinel catalysts have shown both high NO conversion and high selectivity to N2. Mn0.95Ca0.05Cr2O4 has shown the best performance, reaching an NO conversion of 96% and a selectivity to N2 of 97% at 125 °C. All the catalysts were then deposited by means of a modified dip-coating procedure over cordierite honeycomb monoliths and tested in a lab-scale test rig. The monolith catalyzed with the Mn0.95Ca0.05Cr2O4 spinel showed the best performance, reaching an NO conversion of 87.4% at 200 °C, with a good selectivity to N2 (94.8%). When the catalyzed monoliths were also tested in the presence of 10 vol % of water vapor, an activity decrease was observed. The correlation between the reducibility of the B site, determined from TPR experiments, and the spinels' catalytic activity order is discussed. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie200227u [article] Low temperature NH3 selective catalytic reduction of NOx over substituted MnCr2O4 spinel-oxide catalysts [texte imprimé] / Miguel A. Zamudio, Auteur ; Nunzio Russo, Auteur ; Debora Fino, Auteur . - 2011 . - pp 6668–6672. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 11 (Juin 2011) . - pp 6668–6672 Mots-clés : Catalysts  X-ray  diffraction Résumé : The present work describes the development of Mn1–xMxCr2O4 (M = Mg, Ca; x = 0–0.1) substituted spinel catalysts prepared via gel combustion synthesis for the low-temperature selective catalytic reduction (SCR) of NOx with NH3. The catalysts have been characterized by means of X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), field emission scanning electron microscopy (FESEM) and temperature programmed reduction (TPR) analyses, whereas their catalytic activity has been tested in a temperature programmed reaction (TPRe) apparatus over a temperature range of 100–200 °C (W/F = 0.072 g·s·cm–3) in the presence of oxygen. The catalytic activity of alkali earth-metal substituted Mn–Cr spinels is compared with that of the stoichiometric MnCr2O4 in order to assess the effect of the substitutions. All the spinel catalysts have shown both high NO conversion and high selectivity to N2. Mn0.95Ca0.05Cr2O4 has shown the best performance, reaching an NO conversion of 96% and a selectivity to N2 of 97% at 125 °C. All the catalysts were then deposited by means of a modified dip-coating procedure over cordierite honeycomb monoliths and tested in a lab-scale test rig. The monolith catalyzed with the Mn0.95Ca0.05Cr2O4 spinel showed the best performance, reaching an NO conversion of 87.4% at 200 °C, with a good selectivity to N2 (94.8%). When the catalyzed monoliths were also tested in the presence of 10 vol % of water vapor, an activity decrease was observed. The correlation between the reducibility of the B site, determined from TPR experiments, and the spinels' catalytic activity order is discussed. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie200227u

NOx abatement by HC - assisted SCR over combustion synthesized - supported Ag catalysts / Murid Hussain in Industrial & engineering chemistry research, Vol. 51 N° 22 (Juin 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 22 (Juin 2012) . - pp. 7467-7474 Titre : NOx abatement by HC - assisted SCR over combustion synthesized - supported Ag catalysts Type de document : texte imprimé Auteurs : Murid Hussain, Auteur ; Nunzio Russo, Auteur ; Guido Saracco, Auteur Année de publication : 2012 Article en page(s) : pp. 7467-7474 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Catalyst  Combustion  Selective  catalytic  reduction  Pollution  abatement Résumé : In this work, catalysts containing 2% by weight of silver particles dispersed on different oxide supports (CeO2, La2O3, ZrO2,Al2O3), and oxides without silver particles were prepared by means of the combustion synthesis method. This cheap and quick technique has been developed to produce very fine, homogeneous, crystalline powders without the intermediate decomposition and/or calcining steps which other conventional synthesis routes require. These features are also interesting for the cosynthesis of supported Ag catalysts; it has in fact been possible in one-shot to achieve values of the Ag clusters (estimated size 5―10 nm) that are comparable with those obtained by means of the more complex methods reported in literature. The catalysts were characterized via XRD, BET, TEM, FESEM-EDS, and XPS analysis. The catalytic performances of the prepared catalysts were evaluated in a TPR apparatus for the selective reduction of NO with benzene in the presence of oxygen. A noticeable enhancement in activity was achieved when the selected oxides were doped with Ag. Lantana and ceria-supported Ag catalysts with good hydrothermal stability were found to perform comparatively well, as a significant NOx to N2 conversion was obtained at temperatures slightly above 250 °C. As far as the results concerning the catalysts are concerned, a synergic effect of the supports with the Ag clusters has been highlighted. Some conclusions may be drawn concerning the reaction mechanism. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25968298 [article] NOx abatement by HC - assisted SCR over combustion synthesized - supported Ag catalysts [texte imprimé] / Murid Hussain, Auteur ; Nunzio Russo, Auteur ; Guido Saracco, Auteur . - 2012 . - pp. 7467-7474. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 22 (Juin 2012) . - pp. 7467-7474 Mots-clés : Catalyst  Combustion  Selective  catalytic  reduction  Pollution  abatement Résumé : In this work, catalysts containing 2% by weight of silver particles dispersed on different oxide supports (CeO2, La2O3, ZrO2,Al2O3), and oxides without silver particles were prepared by means of the combustion synthesis method. This cheap and quick technique has been developed to produce very fine, homogeneous, crystalline powders without the intermediate decomposition and/or calcining steps which other conventional synthesis routes require. These features are also interesting for the cosynthesis of supported Ag catalysts; it has in fact been possible in one-shot to achieve values of the Ag clusters (estimated size 5―10 nm) that are comparable with those obtained by means of the more complex methods reported in literature. The catalysts were characterized via XRD, BET, TEM, FESEM-EDS, and XPS analysis. The catalytic performances of the prepared catalysts were evaluated in a TPR apparatus for the selective reduction of NO with benzene in the presence of oxygen. A noticeable enhancement in activity was achieved when the selected oxides were doped with Ag. Lantana and ceria-supported Ag catalysts with good hydrothermal stability were found to perform comparatively well, as a significant NOx to N2 conversion was obtained at temperatures slightly above 250 °C. As far as the results concerning the catalysts are concerned, a synergic effect of the supports with the Ag clusters has been highlighted. Some conclusions may be drawn concerning the reaction mechanism. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25968298