Готові списки джерел за темами / Catalyst aging

Добірка наукової літератури з теми "Catalyst aging"

Автор: Grafiati
Опубліковано: 14 березня 2023

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Статті в журналах з теми "Catalyst aging"

1

Schütz, Jochen, Heike Störmer, Patrick Lott, and Olaf Deutschmann. "Effects of Hydrothermal Aging on CO and NO Oxidation Activity over Monometallic and Bimetallic Pt-Pd Catalysts." Catalysts 11, no. 3 (February 25, 2021): 300. http://dx.doi.org/10.3390/catal11030300.

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By combining scanning transmission electron microscopy, CO chemisorption, and energy dispersive X-ray spectroscopy with CO and NO oxidation light-off measurements we investigated deactivation phenomena of Pt/Al2O3, Pd/Al2O3, and Pt-Pd/Al2O3 model diesel oxidation catalysts during stepwise hydrothermal aging. Aging induces significant particle sintering that results in a decline of the catalytic activity for all catalyst formulations. While the initial aging step caused the most pronounced deactivation and sintering due to Ostwald ripening, the deactivation rates decline during further aging and the catalyst stabilizes at a low level of activity. Most importantly, we observed pronounced morphological changes for the bimetallic catalyst sample: hydrothermal aging at 750 °C causes a stepwise transformation of the Pt-Pd alloy via core-shell structures into inhomogeneous agglomerates of palladium and platinum. Our study shines a light on the aging behavior of noble metal catalysts under industrially relevant conditions and particularly underscores the highly complex transformation of bimetallic Pt-Pd diesel oxidation catalysts during hydrothermal treatment.
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2

Wang, Tae Joong, and In Hyuk Im. "Experimental and kinetic analysis of hydrothermal aging effects on ammonia adsorption capacity over a commercial Cu-zeolite selective catalytic reduction catalyst." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 233, no. 12 (November 28, 2018): 3030–42. http://dx.doi.org/10.1177/0954407018814950.

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Ammonia/urea selective catalytic reduction is an efficient technology to control NOx emission from diesel engines. One of its critical challenges is the performance degradation of selective catalytic reduction catalysts due to the hydrothermal aging experienced in real-world operations during the lifetime. In this study, hydrothermal aging effects on the reduction of ammonia adsorption capacity over a commercial Cu-zeolite selective catalytic reduction catalyst were investigated under actual engine exhaust conditions. Ammonia adsorption site densities of the selective catalytic reduction catalysts aged at two different temperatures of 750°C and 850°C for 25 h with 10% H2O were experimentally measured and compared to that of fresh catalyst on a dynamometer test bench with a heavy-duty diesel engine. The test results revealed that hydrothermal aging significantly decreased the ammonia adsorption capacity of the current commercial Cu-zeolite selective catalytic reduction catalyst. Hydrothermal treatment at 750°C reduced the ammonia adsorption site to 62.5% level of that of fresh catalyst, while hydrothermal treatment at 850°C lowered the adsorption site to 37.0% level of that of fresh catalyst. Also, in this study, numerical simulation and kinetic analysis were carried out to quantify the impact of hydrothermal aging on the reduction of ammonia adsorption capacity by introducing an aging coefficient. The kinetic parameter calibrations based on actual diesel engine tests with a commercial monolith Cu-zeolite selective catalytic reduction catalyst provided a highly realistic kinetic parameter set of ammonia adsorption/desorption and enabled a mathematical description of hydrothermal aging effect.
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3

Kiss, Ernő, and Goran Boskovic. "Impeded solid state reactions and transformations in ceramic catalysts supports and catalysts." Processing and Application of Ceramics 6, no. 4 (2012): 173–82. http://dx.doi.org/10.2298/pac1204173k.

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Impeded chemical reactions and impeded polymorphous transformation in materials are discussed, as desired effects, for stabilization of ceramic catalyst supports and ceramic based catalysts. This paper gives a short overview about the possibilities of slowing down the aging processes in ceramic catalyst supports and catalysts. Special attention is given to alumina and titania based catalysts.
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4

Zhang, Wei Jun, Jin Hu, Hong Luo, Li Shen, Hua Tan, and Lin Su. "Relation between Cell Density and PM Content Investgation of Three-Way Catalyst." Advanced Materials Research 624 (December 2012): 291–94. http://dx.doi.org/10.4028/www.scientific.net/amr.624.291.

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In this paper, Pd/Rh series catalyst substrate samples were prepared at the different cell density, with different volume. The fresh catalyst aging treatment. And Catalysts test by light-off factor (LOF). The results tested demonstrated that, it can achieve equal performance levels with the cell density is 600cpsi that the catalyst sample of the cell density is 400cpsi with the precious metal content for the 1.2g/L. This is more efficient for low content of noble metal catalysts. This work is still importantly to promoted catalyst stability, that the catalyst structure is optimized. And it can be used as the interaction between cell density and noble metal content of catalysts.
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5

Morosanu, Eduard Alexandru, Fabio Salomone, Raffaele Pirone, and Samir Bensaid. "Insights on a Methanation Catalyst Aging Process: Aging Characterization and Kinetic Study." Catalysts 10, no. 3 (March 2, 2020): 283. http://dx.doi.org/10.3390/catal10030283.

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Power to gas systems is one of the most interesting long-term energy storage solutions. As a result of the high exothermicity of the CO2 methanation reaction, the catalyst in the methanation subsystem is subjected to thermal stress. Therefore, the performance of a commercial Ni/Al2O3 catalyst was investigated over a series of 100 hour-long tests and in-process relevant conditions, i.e. 5 bar from 270 to 500 °C. Different characterization techniques were employed to determine the mechanism of the observed performance loss (N2 physisorption, XRD, TPO). The TPO analysis excluded carbon deposition as a possible cause of catalyst aging. The BET analysis evidenced a severe reduction in the total surface area for the catalyst samples tested at higher temperatures. Furthermore, a direct correlation was found between the catalyst activity decline and the drop of the catalyst specific surface. In order to correctly design a reliable methanation reactor, it is essential to have a kinetic model that includes also the aging kinetics. For this purpose, the second set of experiments was carried out, in order to determine the intrinsic kinetics of the catalyst. The kinetic parameters were identified by using nonlinear regression analysis. Finally, a power-law aging model was proposed to consider the performance loss in time.
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6

Song, Chaoming, Lihong Zhang, Zhenguo Li, Yiren Lu, and Kaixiang Li. "Co-Exchange of Mn: A Simple Method to Improve Both the Hydrothermal Stability and Activity of Cu–SSZ-13 NH3–SCR Catalysts." Catalysts 9, no. 5 (May 17, 2019): 455. http://dx.doi.org/10.3390/catal9050455.

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A series of Cu–Mn–SSZ-13 catalysts were obtained by co-exchange of Mn and Cu into SSZ-13 together (ion exchange under a mixed solution of Cu(NO3)2 and Mn(NO3)2) and compared with Cu–SSZ-13 catalysts on the selective catalytic reduction (SCR) of nitric oxide (NO) by ammonia. The effects of total ion exchange degree and the effect of Mn species on the structure and performance of catalysts before and after hydrothermal aging were studied. All fresh and aged catalysts were characterized with several methods including temperature-programmed desorption with NH3 (NH3-TPD), X-ray diffraction (XRD), 27Al and 29Si solid-state nuclear magnetic resonance (NMR), scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) and low-temperature N2 adsorption–desorption techniques. The results showed that the increase of the total ion exchange degree can reduce the content of residual Brønsted acid sites of catalysts, thus relieved the dealumination and the decrease of crystallinity of the catalyst during hydrothermal aging. The moderate addition of a Mn component in Cu–Mn–SSZ-13 catalysts significantly increased the activity of NO conversion at low temperature range. The selected Cu(0.2)Mn(0.1)–SSZ-13 catalyst achieved a high NO conversion of >90% in the wide and low temperature range of 175–525 °C and also exhibited good N2 selectivity and excellent hydrothermal stability, which was related to the inhibition of the Mn component on the aggregation of Cu species and the pore destruction of the catalyst during hydrothermal aging.
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7

Kawanami, Yasuhiro, and Ryo Yanagita. "Practical Enantioselective Reduction of Ketones Using Oxazaborolidine Catalysts Generated In Situ from Chiral Lactam Alcohols." Molecules 23, no. 10 (September 20, 2018): 2408. http://dx.doi.org/10.3390/molecules23102408.

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Oxazaborolidine catalyst (CBS catalyst) has been extensively used for catalytic borane reduction with a predictable absolute stereochemistry and high enantioselectivity. However, the use of isolated CBS catalyst sometimes has the drawback of low reproducibility due to the aging of the CBS catalyst during storage. Therefore, we investigated a more reliable and practical method for the reduction of a variety of ketones including challenging substrates, primary aliphatic ketones, α,β-enones, and trifluoromethyl ketones. This review surveys the developments in borane reduction using oxazaborolidine catalysts generated in situ from chiral lactam alcohols and borane.
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8

Khandavalli, Sunilkumar, Jaehyung Park, Robin Rice, Guido Bender, Deborah J. Myers, Michael Ulsh, and Scott A. Mauger. "Tuning the Rheology of Anode Inks with Aging for Low-Temperature Polymer Electrolyte Membrane Water Electrolyzers." ECS Meeting Abstracts MA2022-02, no. 40 (October 9, 2022): 1483. http://dx.doi.org/10.1149/ma2022-02401483mtgabs.

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Low-temperature polymer electrolyte membrane water electrolyzers (PEMWE) are an attractive clean energy technology to produce hydrogen (H2), which is an energy carrier for several applications such as transportation and grid-scale energy storage and distribution (as supported by the US Department of Energy’s H2@Scale initiative). The catalyst layers -- composed of catalyst particles and ionomer, which acts as a binder for the catalyst and a proton conducting medium -- are key components of the PEMWE membrane electrode assembly (MEA). The catalyst layers are commonly fabricated by solution-processing an ink, which is a mixture of catalyst and ionomer often dispersed in a water-alcohol solvent mixture. Tuning the rheological properties of the anode inks (typically composed of iridium oxide catalyst, IrOx), particularly increasing their viscosity without significantly increasing the solids loading, to suit various scalable coating methods, is generally a challenge due to relatively low porosity and high density of the IrOx catalysts compared to the carbon-supported cathode catalysts. The typically low viscosities of the anode inks combined with high particle densities often cause stability/settling issues and challenges obtaining unform coatings, leading to inhomogeneous distribution of the catalyst that may have a negative effect on electrode performance. In this presentation we report on a dramatic enhancement in the viscoelasticity of the anode inks with aging, where the ink transitions from a liquid-like to a weak gel-like structure. The steady-shear and oscillatory shear rheology characterizations of the inks as a function of aging/time, the impact of formulation conditions (ionomer-to-catalyst ratio and dispersion media composition) on the viscoelastic enhancement with aging, and possible mechanisms for the observed behavior will be discussed. In addition to the rheological measurements, X-ray scattering characterization of the ink structure will be presented. The implications of the rheological changes on ink stability and processing will also be discussed. Additionally the impact of ink age on MEA performance will be presented.
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9

Zhao, Hong Xia, and Hai Liang Lü. "Study of Co/ZrO2 Catalysts in Fischer-Tropsch Synthesis." Advanced Materials Research 850-851 (December 2013): 120–23. http://dx.doi.org/10.4028/www.scientific.net/amr.850-851.120.

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The investigation has been conducted to establish the effect of preparation methods on the textural properties, the metal-support interaction of the Co/ZrO2 catalysts and consequently its influence on Fischer-Tropsch synthesis. Coprecipitated Co/ZrO2 catalyst showed the strongest cobalt-zirconia interaction, the lowest reduction degree, and the lowest catalytic activity. Impregnated Co/ZrO2 catalyst showed the weakest cobalt-zirconia interaction, the highest reduction degree and the highest catalytic activity, while Co/ZrO2 catalyst prepared by directly impregnation Zr (OH)4 with cobalt nitrate solution were in the middle of CZC and CZI. The differences among the three catalysts could be ascribed to the different aging time of the support.
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10

Jiang, J. C., X. Q. Pan, G. W. Graham, R. W. McCabe, and J. Schwank. "Transmission Electron Microscopy Studies of Pd Encapsulation by Ceria-Zirconia Oxides." Microscopy and Microanalysis 4, S2 (July 1998): 724–25. http://dx.doi.org/10.1017/s1431927600023746.

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High-temperature catalysts containing Pd supported on high-surface area ceria-zirconia are optimum materials for fuel economy when automotive engines operate under high speed or load conditions. A prerequisite for developing such thermally stable catalysts is to gain a good understanding of the thermal deactivation modes contributing to the aging and degradation of catalysts in harsh thermal environments. It was discovered by X-ray diffraction that upon hightemperature aging, Pd may sinter into large (about 10 nm diameter) particles and become encapsulated in the ceria-zirconia. To confirm this conclusion, a prototype high-temperature catalyst containing Pd supported on high-surface area ceria-zirconia, aged at temperature above 1100 °C is studied by transmission electron microscopy (TEM).The ceria-zirconia supported Pd (0.25 wt%) catalyst was aged at 1105 °C and calcined at 700 °C for 2 h. For TEM sample preparations, first of all, a large-size aggregate with diameter about 1 mm was selected and sandwiched between by two pieces of silicon crystal.
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Дисертації з теми "Catalyst aging"

1

Li, Haitao. "Supercritical carbon dioxide aided preparation of nickel oxide/alumina aerogel catalyst." [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001090.

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2

MOROSANU, EDUARD ALEXANDRU. "Catalytic processes for CO2 conversion into Synthetic Methane." Doctoral thesis, Politecnico di Torino, 2020. http://hdl.handle.net/11583/2841162.

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3

Kandilli, Nur. "Development Of A Three Way Catalytic Converter For Elimination Of Hydrocarbons, Carbon Monoxide And Nitric Oxide In Automotive Exhaust." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612546/index.pdf.

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In this work, slurries of powder catalysts are washcoated on 22 mm diameter and 13 mm height cordierite monoliths. CeO2-ZrO2 (CZO) and CeO2-ZrO2- Al2O3 (CZAO) mixed oxides are synthesized by co-precipitation and sol-gel methods respectively, to be used as support materials of Pd and Rh metals. Metal loaded CZO is mixed with gamma phase alumina. Powder catalysts and their slurries are characterized by XRD, BET, ICP-MS and the monolithic catalysts are imaged by SEM. Catalytic activities of monolithic catalysts are tested in dynamic test system which is computerized and basically composed of gas flow control and conditioning units, split furnace, quartz reactor, mass spectrometer and CO analyzer. Gas mixture containing CO, C3H6, C3H8, NO, H2, O2, CO2, SO2, H2O and N2 is used to simulate the exhaust gas of gasoline vehicles. O2 is oscillated at 1 Hz frequency around the stoichiometric condition. Monolithic catalyst in the reactor is heated and cooled between 150 º
C and 600 º
C. Gas composition data from massspectrometer and CO analyzer and temperature data from thermocouple at the monolith entrance, are converted to conversion versus temperature graphs. Results of 26 activity tests are compared. Catalyst containing coimpregnated CZO support material with metals, showed the lowest loss of catalytic performance after exposure to SO2 during activity tests. Catalyst containing separately impregnated CZO support material, showed the highest resistance against thermal aging at 900 º
C and 1000 º
C, and even improved catalytic activity after aging. These catalysts showed higher resistances against the applied procedures than the commercial catalyst.
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4

Birgersson, Henrik. "Development and Assessment of Regeneration Methods for Commercial Automotive Three-Way Catalysts." Doctoral thesis, Stockholm, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3931.

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5

Panpranot, Joongjai. "Hydrothermal aging of zeolite-based catalysts." Morgantown, W. Va. : [West Virginia University Libraries], 1998. http://etd.wvu.edu/templates/showETD.cfm?recnum=274.

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Thesis (M.S.)--West Virginia University, 1998.
Title from document title page. Document formatted into pages; contains xi, 84 p. : ill. Includes abstract. Includes bibliographical references (p. 64-67).
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6

Blades, Luke Aubrey William. "Ageing mechanisms in automotive catalysts." Thesis, Queen's University Belfast, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.695255.

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This study uses a number of laboratory testing and ageing methods in order to investigate how effectively they correlate to catalyst ageing on a vehicle. The activity testing of full size catalyst bricks was successfully conducted using the Catagen Labcat test system, and correlation with the light-off activity of cored catalyst samples in the Horiba SIGU 2000 examined using the QUB global catalyst model. Static ageing was conducted in the laboratory, using the BAT equation to calculate ageing times for ageing temperatures relating to a RAT-A cycle. The thermal reactivity coefficients for static ageing in different ageing atmospheres were calculated and compared to those recommended by the EPA for dynamic ageing. Finally, using the results achieved from these raboratory ageing methods, recommendations were made as to how ageing models reviewed in the literature could be improved. From experimental results alone, it was seen that no correlation existed between the light-off performance of cored catalyst samples and full size bricks. However, the QUB global catalyst model was able to consider variations in precious metal dispersion between samples, differences between inlet temperature and gas concentrations, and heat transfer characteristics of the two reactors. The simulations performed were able to show good correlation between the test methods. However, the two tests methods showed differently the activity rank of the samples, indicating the variation in precious metal loading and dispersion throughout each full size brick. In other results, static ageing of palladium loaded catalyst samples was found to show no ageing effects due to time for ageing temperatures below 1000 C. Static ageing methods were also shown to cause deactivation at a slower rate than dynamic methods. It was shown that the Toyota ageing expression would better predict catalyst deactivation if it incorporated an oxygen factor, to describe ageing when no oxygen is present.
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Woods, Andrew John. "Ageing and characterisation of automotive catalysts." Thesis, Queen's University Belfast, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.486263.

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Catalytic converter technologies situated in the exhaust streams of vehicles are under continuing pressure to meet more stringent emissions standards that requires increasing longevity along with higher efficiencies. This investigation studied the fundamental factors known to contribute to catalyst deactivation, by developing the specific designs and by construction of ageing facilities that isolated the ageing factors under inspection. Various static ageing schedules were completed along with rapid ageing cycles with the aid of a custom built synthetic gas ageing machine named AutoCAS, (Automotive Catalyst Ageing System). Explicit characterisation techniques to help define the extent of catalyst degradation were also developed. These focused on use of scanning electron, microscopy and transmission electron microscopy to produce images of the catalyst which could then be analysed using image analysis software. The software program enabled statistical data to be collated, allowing conclusions to be drawn about the surface structure before and after ageing. Raman spectroscopy was used to probe the changes in catalyst substrate after the ageing process. Results uncovered that Platinum/Rhodium, (PtIRh), catalysts behave differently to Palladium, Pd, catalysts with respect to particle agglomeration. Pd loaded samples exhibited relationships with respect to ageing time and temperature whilst PtlRh catalysts were only susceptible to ageing temperature. Also, concluded was that PtlRh catalysts undergo agglomeration in an inert nitrogen environment which is in direct contradiction to mathematical expressions already published. Precious metal particle agglomeration was found to have a relatively insignificant role to play in overall catalyst deactivation. RATA ageing showed that the thermal stressing incurred by thermal cycling affected the catalyst activity more so than ageing at uniform temperature. Application ofthe current QUB catalyst model showed that there may be other factors contributing to deactivation rather than just washcoat sintering and precious metal agglomeration as measured in this research.
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8

Rachele, Karen Gonçalves. "Estudo de catalisadores modelo à base de CeO2-ZrO2 dopado com cobre para controle de emissões de NOx." Universidade do Estado do Rio de Janeiro, 2012. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=5048.

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Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro
Convencionalmente, metais nobres são empregados como metais ativos em catalisadores automotivos, mas o uso de cobre vem sendo estudado pelo fato de promover sítios ativos para adsorção química e redução de NOx. Diante deste contexto, esta dissertação visa testar novas formulações de catalisadores, com foco em seu desempenho na reação de redução do NO pelo CO e sua seletividade a N2. Foram avaliados o método de adição de cobre no preparo e os teores de cobre utilizados na preparação. Os métodos de adição utilizados foram impregnação a seco (IS), reação em estado sólido (RS) e coprecipitação (CO). Os teores de cobre estudados ficaram entre 0,36 e 6,9% (m/m). Além disso, foi estudado o impacto no desempenho do catalisador após envelhecimento térmico a 950C por 12h. Foram empregadas as seguintes técnicas de caracterização textural e físico-química como espectrometria de absorção atômica, fisissorção de N2, difração de raios X, espectroscopia Raman e redução a temperatura programada. Os catalisadores também foram avaliados na reação de redução do NO pelo CO. A análise textural indicou que o método de coprecipitação levou a características texturais diferentes dos outros catalisadores. Análises de DRX mostraram a formação de CuO cristalino para teores iguais ou superiores a 3,3% (m/m) de cobre. As análises de Redução a Temperatura Programada (RTP) indicaram que ocorreu uma forte interação na interface entre o suporte e as espécies de cobre dispersas, acompanhada da diminuição da temperatura de redução do CuO e da redução parcial da céria em temperaturas mais baixas. Os testes catalíticos mostraram um melhor desempenho dos catalisadores (IS) que apresentaram conversões mais elevadas em menores temperaturas. Com relação ao envelhecimento, observou-se uma diminuição significativa da eficiência dos catalisadores. Uma comparação com catalisadores à base de metal nobre mostrou um bom desempenho dos catalisadores à base de cobre, com a vantagem destes apresentarem emissão de N2O restrita a baixas temperaturas
Conventionally, noble metals are used as active metals in automotive catalytic converters, but the use of copper has been studied because copper promote active sites for chemical adsorption and reduction of NOx. Thus, this work aims to test new formulations of automotive catalysts, focusing on their performance in catalytic reduction of NO by CO and its selectivity to N2. The method of copper addition and the copper contents used in the preparation were evaluated. The addition methods used were dry impregnation (IS), solid state reaction (RS) and coprecipitation (CO). The copper contents studied were between 0,36 e 6,9 wt%. In addition, the impact on catalyst performance after thermal aging at 950 C for 12h was also studied. Textural and physico-chemical caracterization techniques were employed, such as atomic absorption spectrometry, N2 physisorption, X-ray diffraction, Raman spectroscopy and temperature programmed reduction. Catalysts were evaluated in the reduction reaction of NO by CO. The textural analysis indicated that addition of copper by the coprecipitation method led to textural characteristics different from the other catalysts. XRD analysis showed the formation of crystalline CuO for contents equal to or greater than 3,3 wt% of copper. TPR analysis indicated that there was a strong interaction at the interface between the substrate and the copper species dispersed together with the lowering of the temperature reduction of CuO and the partial reduction of ceria at lower temperatures. The catalytic activity results showed a better performance of the (IS) catalysts, which showed higher conversions at lower temperatures. Concerning the aging process, there was a significant decrease in the efficiency of the catalysts. A comparison with catalysts doped with noble metal showed good performance of the catalysts doped with copper, with the advantage of these presenting N2O emission restricted to low temperatures
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9

Casapu, Maria Cristina. "NOx storage-reduction catalysts : material aspects, thermal ageing and reactivation." kostenfrei, 2007. http://e-collection.ethbib.ethz.ch/view/eth:30178.

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10

Wang, Fagen. "Hydrogen production from steam reforming of ethanol over an Ir/ceria-based catalyst : catalyst ageing analysis and performance improvement upon ceria doping." Phd thesis, Université Claude Bernard - Lyon I, 2012. http://tel.archives-ouvertes.fr/tel-00967128.

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The objective of the thesis was to analyze the ageing processes and the modifications of an Ir/CeO2catalyst for steam reforming of ethanol. Over a model Ir/CeO2 catalyst, the initial and fast deactivationwas ascribed to ceria surface restructuring and the build-up of intermediates monolayer (acetate,carbonate and hydroxyl groups). In parallel, a progressive and slow deactivation was found to come fromthe structural changes at the ceria/Ir interface linked to Ir sintering and ceria restructuring. Theencapsulating carbon, coming from C2 intermediates polymerization, did not seem too detrimental to theactivity in the investigated operating conditions. By doping ceria with PrOx, the oxygen storage capacityand thermal stability were greatly promoted, resulting in the enhanced activity and stability. The Ir/CeO2catalyst was then modified by changing the shape of ceria. It was found that the shape and therefore thestructure of ceria influenced the activity and stability significantly. A simplified modeling of theseprocesses has contributed to support the new proposals of this work.
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Частини книг з теми "Catalyst aging"

1

Wang, Xueqin, and Xiangsheng Wang. "Aging and Coke Depositing on Nanometer ZSM-5 Zeolite." In Combinatorial Catalysis and High Throughput Catalyst Design and Testing, 447–50. Dordrecht: Springer Netherlands, 2000. http://dx.doi.org/10.1007/978-94-011-4329-5_22.

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2

Patel, Mogon, Steve Black, and Julian Murphy. "Aging Complexities Induced by the Organotin Catalyst in Foamed Polysiloxane Elastomers." In ACS Symposium Series, 16–25. Washington, DC: American Chemical Society, 2007. http://dx.doi.org/10.1021/bk-2007-0978.ch002.

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3

Vaisnav, S. Mithun, and Sivanesan Murugesan. "Temperature Control Methodology for Catalytic Convertor to Reduce Emissions and Catalyst Aging." In Intelligent Manufacturing and Energy Sustainability, 239–47. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-16-6482-3_24.

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4

Weber, S., J. C. W. Chien, and Y. Hu. "Determination of the Titanium Oxidation States in a MgCl2-Supported Ziegler-Natta Catalyst (CW-Catalyst) During Aging and Polymerization." In Transition Metals and Organometallics as Catalysts for Olefin Polymerization, 45–53. Berlin, Heidelberg: Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/978-3-642-83276-5_5.

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5

Shuai, Shijin, Yinhui Wang, Junfeng Chen, and Jianhua Xiao. "Experimental Study of Influence of Gasoline Fuel with MMT on Aging Performance of Three-Way Catalyst." In Lecture Notes in Electrical Engineering, 571–83. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-33841-0_44.

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6

Bush, Ashley I., and Lee E. Goldstein. "Specific Metal-Catalysed Protein Oxidation Reactions in Chronic Degenerative Disorders of Ageing: Focus on Alzheimer's Disease and Age-Related Cataracts." In Ageing Vulnerability: Causes and Interventions, 26–43. Chichester, UK: John Wiley & Sons, Ltd, 2008. http://dx.doi.org/10.1002/0470868694.ch4.

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7

Bailly, C., A. Benamar, F. Corbineau, and D. Côme. "Changes in Superoxide Dismutase, Catalase and Glutathione Reductase Activities in Sunflower Seeds during Accelerated Ageing and Subsequent Priming." In Basic and Applied Aspects of Seed Biology, 665–72. Dordrecht: Springer Netherlands, 1997. http://dx.doi.org/10.1007/978-94-011-5716-2_74.

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Tian, Huiping, Congjun Huang, and Zhongbi Fan. "Metals on a Novel USY Zeolite after Hydrothermal Aging." In Catalyst Deactivation 2001, Proceedings of the 9th International Symposium, 351–58. Elsevier, 2001. http://dx.doi.org/10.1016/s0167-2991(01)80217-2.

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9

Bart, J. M., M. Prigent, and A. Pentenero. "Study of hydrocarbons removal with a three-way automotive catalyst after severe thermal aging." In Catalysis and Automotive Pollution Control III, Proceedings of the Third International Symposium CAPoC 3, 813–28. Elsevier, 1995. http://dx.doi.org/10.1016/s0167-2991(06)81477-1.

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Sarkany, A. "Self-poisoning and aging of Pd-Ag/Al2O3 in semi-hydrogenation of 1,3-butadiene: Effects of surface inhomogeneity caused by hydrocarbonaceous deposits." In Catalyst Deactivation, Proceedings of the 7th International Symposium, 111–18. Elsevier, 1997. http://dx.doi.org/10.1016/s0167-2991(97)80145-0.

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Тези доповідей конференцій з теми "Catalyst aging"

1

Hepburn, Jeffrey, Timothy Chanko, JoAnne McKenzie, Robert Jerger, and Douglas Dobson. "OBD-II Threshold Catalyst Aging Process." In 1997 SAE International Fall Fuels and Lubricants Meeting and Exhibition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 1997. http://dx.doi.org/10.4271/972853.

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2

Kim, Jeong Y., Yisun Cheng, Joseph E. Patterson, Paul M. Laing, and Christine K. Lambert. "Modeling Study of Urea SCR Catalyst Aging Characteristics." In SAE World Congress & Exhibition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2007. http://dx.doi.org/10.4271/2007-01-1580.

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3

Ruetten, Oliver, Stefan Pischinger, Carsten Küpper, Rolf Weinowski, David Gian, Dmitry Ignatov, Winston Betton, and Michael Bahn. "Catalyst Aging Method for Future Emissions Standard Requirements." In SAE 2010 World Congress & Exhibition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2010. http://dx.doi.org/10.4271/2010-01-1272.

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4

Mooney, J. J., W. M. Rudy, L. A. Lautman, and H. S. Hwang. "High Temperature Aging Cycle for European Catalyst Applications." In 1985 SAE International Fall Fuels and Lubricants Meeting and Exhibition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 1985. http://dx.doi.org/10.4271/852098.

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5

Wang, Weidong, Shi Xu, Xiaoming Li, Gang Xu, Tianpeng Han, Jun Yue, Xinhua Li, and Liwei Jia. "Study on Rapid Aging Method of CNG Catalyst." In WCX SAE World Congress Experience. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2022. http://dx.doi.org/10.4271/2022-01-0586.

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6

Burkholder, S. P., and Barry J. Cooper. "Effect of Aging and Testing Conditions on Catalyst Performance." In Automotive Industry in Expanding Countries. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 1991. http://dx.doi.org/10.4271/911734.

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7

McGuire, Nicholas E., Neal P. Sullivan, Robert J. Kee, Huayang Zhu, James A. Nabity, Jeffrey R. Engel, David T. Wickham, and Michael Kaufman. "Hexaaluminate Catalysts for Fuel Reforming." In ASME 2008 6th International Conference on Fuel Cell Science, Engineering and Technology. ASMEDC, 2008. http://dx.doi.org/10.1115/fuelcell2008-65231.

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Анотація:
Hexaaluminate catalysts offer excellent high-temperature stability compared to the equivalent metal-based catalysts. Their stability also lends well to use as a catalyst support. However, use of novel hexaaluminates is limited in fuel processing for fuel-cell applications. In this paper, we report on the performance of hexaaluminates as a catalyst support in the steam reforming of methane. The hexaaluminates are synthesized by a metal-exchange process using alumoxane precursors that enable a wide range of metal substitutions. Performance is evaluated using a unique stagnation-flow reactor that enables detailed probing of the boundary layer above the catalyst-impregnated stagnation surface. Experimental results are compared with models to understand fundamental reaction kinetics and optimize catalyst performance. RhSr-substituted hexaaluminates with a Rh impregnation are shown to yield the best performance. Scanning- and Transmission-Electron Microscopy are used to characterize the different types of hexaaluminates, and to examine the effect of aging on catalyst structure.
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8

Petersson, Martin, Martin Bergqvist, Ingemar Gottberg, Jeffrey B. Hoke, and Ronald M. Heck. "PremAir® Catalyst System - Long-term On-road Aging Results." In International Fuels & Lubricants Meeting & Exposition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2000. http://dx.doi.org/10.4271/2000-01-2925.

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9

Nagashima, Ken, and Makoto Nagata. "Modeling of Catalyst Sintering and Study of Accelerated Aging Based on Pt/Al2o3 as a Model Catalyst." In SAE World Congress & Exhibition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2007. http://dx.doi.org/10.4271/2007-01-1134.

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10

Cheng, Yisun, and Yinyan Huang. "Deactivation of Cu/Zeolite SCR Catalyst under Lean-Rich Aging Conditions." In SAE 2010 World Congress & Exhibition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2010. http://dx.doi.org/10.4271/2010-01-1180.

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Звіти організацій з теми "Catalyst aging"

1

Holladay, Jamelyn. Fundamental Understanding of Cu-zeolite SCR Catalyst Aging Mechanism - CRADA 452. Office of Scientific and Technical Information (OSTI), February 2021. http://dx.doi.org/10.2172/1827785.

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