The Experts below are selected from a list of 1410 Experts worldwide ranked by ideXlab platform
Yaoqiang Chen - One of the best experts on this subject based on the ideXlab platform.
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the promotional role of ni in fevo4 tio2 Monolith Catalyst for selective catalytic reduction of nox with nh3
Applied Surface Science, 2018Co-Authors: Ganxue Wu, Xi Feng, Hailong Zhang, Yanhua Zhang, Jianli Wang, Yaoqiang ChenAbstract:Abstract The promotional effect of nickel additive on the catalytic performance of the representative FeVO 4 /TiO 2 for NH 3 -SCR reaction is systematically studied for the first time in the present work. The experimental results showed that NO x conversion at low temperature and N 2 selectivity could be significantly improved by Ni doping and 0.4Ni-FeV-Ti exhibited the highest NO x removal efficiency. Analysis by XRD, SEM/HR-TEM, Raman, TPD, DRIFTS, TPR and XPS showed that nickel doping effectively promoted the interaction of FeVO 4 nanoparticles with TiO 2 , consequently resulting in an enhanced acidity property, improved redox activity and giving rise to the formation of the surface oxygen vacancies and defect sites.
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the promotional effect of ce on cufe beta Monolith Catalyst for selective catalytic reduction of nox by ammonia
Chemical Engineering Journal, 2016Co-Authors: Xi Feng, Haidi Xu, Maochu Gong, Yaoqiang Chen, Yuanshan LiAbstract:Abstract The Cu 3 Fe 3 /beta and Cu 3 Fe 3 /Ce/beta Catalysts were prepared by incipient wetness impregnation method, their activity, hydrothermal stability and C 3 H 6 resistance for selective catalytic reduction of NO x with ammonia (NH 3 -SCR) were investigated systematically. The experimental results indicated that Cu 3 Fe 3 /Ce/beta performed better NH 3 -SCR performance, because the dispersion of Fe and/or Cu species of Cu 3 Fe 3 /Ce/beta was higher than that of Cu 3 Fe 3 /beta. In addition, the hydrothermal stability of Cu 3 Fe 3 /beta was improved by the addition of Ce. The results of N 2 adsorption-desorption, XRD and NH 3 -TPD, showed that the change of the texture, structure and acid density of Cu 3 Fe 3 /Ce/beta was slighter than that of Cu 3 Fe 3 /beta after hydrothermal aging, the results of UV–vis DRS indicated that the aggregation of metal ions during hydrothermal aging process was inhibited by the introduction of Ce. Furthermore, compared to Cu 3 Fe 3 /beta, less amount of C 3 H 6 /O 2 was adsorbed on Cu 3 Fe 3 /Ce/beta, thus, the C 3 H 6 resistance of Cu 3 Fe 3 /Ce/beta was better than that of Cu 3 Fe 3 /beta. In conclusion, the catalytic activity, hydrothermal stability and C 3 H 6 resistance of Cu 3 Fe 3 /beta were improved by the addition of Ce.
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cerium promotion on the hydrocarbon resistance of a cu sapo 34 nh3 scr Monolith Catalyst
Catalysis Science & Technology, 2015Co-Authors: Xi Feng, Zhengzheng Yang, Haidi Xu, Zheqi Li, Maochu Gong, Yaoqiang ChenAbstract:CuCe-SAPO-34 (CuCe-x) Catalysts with 3 wt% Cu and various content of Ce for selective catalytic reduction of NOx by NH3 (NH3-SCR) were prepared by a wet co-impregnation method. The activities of the CuCe-x Catalysts were better than that of Cu-SAPO-34 (Cu). In addition, the hydrocarbon (HC) resistance of the CuCe-x Catalysts was examined and compared to that of the Cu Catalyst. The NH3-SCR performance after C3H6 poisoning of the CuCe-x Catalysts was preferable to that of the Cu Catalyst, since the C3H6 oxidation performance was improved by the addition of Ce. The XRD, UV-vis-DRS and H2-TPR results confirmed that the addition of Ce could inhibit the aggregation of CuO crystallites and increase the amount of isolated copper ions. Furthermore, the NH3-TPD and TGA results demonstrated that the addition of Ce decreased the amount and strength of strong acid sites, so that the amount of C3H6/O2 adsorption on the CuCe-x Catalysts was lower than that on the Cu Catalyst. Therefore, the activity and HC resistance of Cu-SAPO-34 was improved by the addition of Ce.
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promotional effect of ce on cu sapo 34 Monolith Catalyst for selective catalytic reduction of nox with ammonia
Journal of Molecular Catalysis A-chemical, 2015Co-Authors: Zhengzheng Yang, Haidi Xu, Maochu Gong, Yaoqiang ChenAbstract:Abstract The activity and hydrothermal stability of Cu-SAPO-34 and CuCe-SAPO-34 for selective catalytic reduction of NO x with ammonia (NH 3 -SCR) were investigated systematically. The Catalysts were prepared by wet-impregnation method, and characterized by N 2 adsorption, X-ray diffraction (XRD), X-ray photoelectron spectrum (XPS), Ultraviolet-visible diffuse reflectance spectrum (UV–vis-DRS), H 2 -temperature programmed reduction (H 2 -TPR) and NH 3 -temperature programmed desorption (NH 3 -TPD). The experimental results of fresh Catalysts suggested that Ce mainly existed on the surface of the Catalyst and was well dispersed in the form of Ce 3+ , and its interaction with copper could improve the dispersion of copper species and increase the amount of isolated Cu 2+ ions, so that CuCe-SAPO-34 performed better NH 3 -SCR activity than Cu-SAPO-34. After hydrothermal aging at 800 °C for 12 h, the characterization results indicated that the introduction of cerium effectively improved the textural and structural stability of SAPO-34 since more cations at the exchange site of SAPO-34 could decrease the concentration of Si O(H) Al bond which was closely related to the damage of the SAPO-34 framework. Moreover, the addition of Ce could prevent the decrease of acid densities, promote the redistribution of CuO during hydrothermal aging and provide higher amount of isolated Cu 2+ ions, leading to superior hydrothermal stability of CuCe-SAPO-34 Catalyst.
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low temperature selective catalytic reduction of no with nh3 over Monolith Catalyst of mnox ceo2 zro2 al2o3
Catalysis Today, 2011Co-Authors: Qiulin Zhang, Haidi Xu, Maochu Gong, Yaoqiang ChenAbstract:Abstract MnOx/CeO2–ZrO2–Al2O3 (MnOx/CZA) Catalysts with different amounts of manganese loading were prepared by incipient wetness impregnation method for selective catalytic reduction (SCR) of NO with NH3 at low temperature. The Catalysts were characterized by N2 adsorption–desorption measurement, XRD, XPS, and H2-TPR. Catalytic activity tests reveal that the MnOx/CZA Catalyst with 10% manganese loading has the best catalytic activity, almost 90% NO is translated to N2 in the temperature range of 143–300 °C. The highly dispersed MnOx species, the good oxidation activity of NO to NO2, the existent synergistic effect between the manganese and cerium oxides, and the various oxidation states of manganese oxides may be the main reasons for the best SCR activity. In addition, the SCR activity is slightly influenced in the presence of SO2 and H2O, while such effect is restorable after heating treatment.
Lisa Zimmermann - One of the best experts on this subject based on the ideXlab platform.
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experimental and modeling study of a dual layer scr pgm nh3 slip Monolith Catalyst asc for automotive scr after treatment systems part 2 validation of pgm kinetics and modeling of the dual layer asc Monolith
Applied Catalysis B-environmental, 2013Co-Authors: Massimo Colombo, Isabella Nova, Enrico Tronconi, Volker Schmeiser, Brigitte Bandlkonrad, Lisa ZimmermannAbstract:Abstract We present herein the final part in the development and validation of a chemically and physically consistent mathematical model of a commercial dual-layer (SCR + PGM) Monolithic NH 3 slip converter (ASC). Specifically, in this conclusive Part 2 of the project we first validate the global kinetic model for the PGM Catalyst component, previously developed in Part 1 over the precursor powders, against data collected over a single-layer coated Monolith. Then, we incorporate validated kinetics for the two individual SCR and PGM components into a dual-layer ASC Monolith Catalyst model and proceed to a systematic validation against experimental catalytic activity data collected over core samples of the dual-layer ASC system. A DOE approach is also adopted in order to secure a uniform coverage of the operating field. A positive interaction of the PGM and SCR catalytic chemistries is emphasized by the data collected over the dual-layer SCR + PGM Monolith Catalyst, leading to largely enhanced N 2 selectivities as compared to a single-layer PGM-only washcoat. We show that such a beneficial interaction between the PGM and SCR chemistries occurs via diffusion/reaction of NH 3 and NO x in the SCR Catalyst layer. Results prove that the dual-layer ASC model can simulate realistically the actual NH 3 slip Catalyst configuration over a wide range of representative conditions.
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Experimental and modeling study of a dual-layer (SCR + PGM) NH3 slip Monolith Catalyst (ASC) for automotive SCR after treatment systems. Part 2. Validation of PGM kinetics and modeling of the dual-layer ASC Monolith
Applied Catalysis B-environmental, 2013Co-Authors: Massimo Colombo, Isabella Nova, Enrico Tronconi, Volker Schmeißer, Brigitte Bandl-konrad, Lisa ZimmermannAbstract:Abstract We present herein the final part in the development and validation of a chemically and physically consistent mathematical model of a commercial dual-layer (SCR + PGM) Monolithic NH 3 slip converter (ASC). Specifically, in this conclusive Part 2 of the project we first validate the global kinetic model for the PGM Catalyst component, previously developed in Part 1 over the precursor powders, against data collected over a single-layer coated Monolith. Then, we incorporate validated kinetics for the two individual SCR and PGM components into a dual-layer ASC Monolith Catalyst model and proceed to a systematic validation against experimental catalytic activity data collected over core samples of the dual-layer ASC system. A DOE approach is also adopted in order to secure a uniform coverage of the operating field. A positive interaction of the PGM and SCR catalytic chemistries is emphasized by the data collected over the dual-layer SCR + PGM Monolith Catalyst, leading to largely enhanced N 2 selectivities as compared to a single-layer PGM-only washcoat. We show that such a beneficial interaction between the PGM and SCR chemistries occurs via diffusion/reaction of NH 3 and NO x in the SCR Catalyst layer. Results prove that the dual-layer ASC model can simulate realistically the actual NH 3 slip Catalyst configuration over a wide range of representative conditions.
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experimental and modeling study of a dual layer scr pgm nh3 slip Monolith Catalyst asc for automotive scr aftertreatment systems part 1 kinetics for the pgm component and analysis of scr pgm interactions
Applied Catalysis B-environmental, 2013Co-Authors: Massimo G Colombo, Isabella Nova, Enrico Tronconi, Volker Schmeiser, Brigitte Bandlkonrad, Lisa ZimmermannAbstract:Abstract We present herein the first of two parts in the development and validation of a chemically and physically consistent mathematical model of a commercial dual-layer (SCR + PGM) Monolithic NH 3 slip converter (ASC). The overall project followed a systematic approach of growing complexity, and its results emphasize the beneficial features of a dual-layer configuration with the SCR Catalyst on top of the PGM component. Specifically, we report in this paper NH 3 /O 2 /NO NO 2 steady-state and transient kinetic runs performed over the PGM component of the dual-layer NH 3 slip Catalyst. The PGM component was tested in a representative temperature range (150–550 °C) in the form of precursor washcoat powders at high space velocities in order to gain kinetic information. From these data an original global PGM kinetic model was developed, which fully accounts for the effects of temperature and of NO 2 /NO x feed ratio (0–1) on NH 3 oxidation. The model considers NO 2 inhibition on NO oxidation, as well as a novel NO 2 inhibition effect on the NH 3 oxidation reactions. Comparative NH 3 /O 2 /NO NO 2 steady-state runs were performed also over two combinations of SCR + PGM powders (sequential double-bed and mechanical mixture). The N 2 selectivity was greater over the mechanical mixture, as in this configuration the unselective NH 3 oxidation products (NO x ) formed over the PGM Catalyst had a chance to further react selectively with NH 3 over the SCR Catalyst. Such a positive interaction between the PGM and the SCR catalytic chemistries was satisfactorily predicted by a model involving the simple superposition of the PGM and SCR kinetics. In the following part of the project the herein developed PGM kinetics, together with consistent SCR kinetics, will be incorporated in a novel dual-layer Monolith Catalyst model and validated against both lab-scale and engine test bench data collected over dual-layer ASC systems.
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Experimental and modeling study of a dual-layer (SCR + PGM) NH3 slip Monolith Catalyst (ASC) for automotive SCR aftertreatment systems. Part 1. Kinetics for the PGM component and analysis of SCR/PGM interactions
Applied Catalysis B-environmental, 2013Co-Authors: Massimo G Colombo, Isabella Nova, Enrico Tronconi, Volker Schmeißer, Brigitte Bandl-konrad, Lisa ZimmermannAbstract:Abstract We present herein the first of two parts in the development and validation of a chemically and physically consistent mathematical model of a commercial dual-layer (SCR + PGM) Monolithic NH 3 slip converter (ASC). The overall project followed a systematic approach of growing complexity, and its results emphasize the beneficial features of a dual-layer configuration with the SCR Catalyst on top of the PGM component. Specifically, we report in this paper NH 3 /O 2 /NO NO 2 steady-state and transient kinetic runs performed over the PGM component of the dual-layer NH 3 slip Catalyst. The PGM component was tested in a representative temperature range (150–550 °C) in the form of precursor washcoat powders at high space velocities in order to gain kinetic information. From these data an original global PGM kinetic model was developed, which fully accounts for the effects of temperature and of NO 2 /NO x feed ratio (0–1) on NH 3 oxidation. The model considers NO 2 inhibition on NO oxidation, as well as a novel NO 2 inhibition effect on the NH 3 oxidation reactions. Comparative NH 3 /O 2 /NO NO 2 steady-state runs were performed also over two combinations of SCR + PGM powders (sequential double-bed and mechanical mixture). The N 2 selectivity was greater over the mechanical mixture, as in this configuration the unselective NH 3 oxidation products (NO x ) formed over the PGM Catalyst had a chance to further react selectively with NH 3 over the SCR Catalyst. Such a positive interaction between the PGM and the SCR catalytic chemistries was satisfactorily predicted by a model involving the simple superposition of the PGM and SCR kinetics. In the following part of the project the herein developed PGM kinetics, together with consistent SCR kinetics, will be incorporated in a novel dual-layer Monolith Catalyst model and validated against both lab-scale and engine test bench data collected over dual-layer ASC systems.
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experimental and modelling study of a dual layer nh3 slip Monolith Catalyst for automotive scr aftertreatment systems
Topics in Catalysis, 2013Co-Authors: Isabella Nova, Massimo Colombo, Enrico Tronconi, Brigitte Bandlkonrad, Volker Schmeißer, Lisa ZimmermannAbstract:The approach to the development of a chemically and physically consistent mathematical model of ASC dual-layer (SCR + PGM) washcoated Monolith converters is herein presented. Steady-state and transient kinetic runs were performed over each one of the two ASC components (SCR and PGM) in the form of powders and also over the two mixed powdered Catalysts, thus acquiring information on the interactions between the SCR and the PGM catalytic chemistries. Global kinetic models were fitted to the SCR and to the PGM Catalyst data, and validated against experiments performed over both washcoated single-layered SCR and PGM Monoliths and over a full dual-layer ASC honeycomb Catalyst (SCR layer on top). It was found that the dual-layer (SCR + PGM) ASC architecture grants increased N2 selectivities compared to a PGM-only washcoat.
Enrico Tronconi - One of the best experts on this subject based on the ideXlab platform.
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experimental and modeling study of a dual layer scr pgm nh3 slip Monolith Catalyst asc for automotive scr after treatment systems part 2 validation of pgm kinetics and modeling of the dual layer asc Monolith
Applied Catalysis B-environmental, 2013Co-Authors: Massimo Colombo, Isabella Nova, Enrico Tronconi, Volker Schmeiser, Brigitte Bandlkonrad, Lisa ZimmermannAbstract:Abstract We present herein the final part in the development and validation of a chemically and physically consistent mathematical model of a commercial dual-layer (SCR + PGM) Monolithic NH 3 slip converter (ASC). Specifically, in this conclusive Part 2 of the project we first validate the global kinetic model for the PGM Catalyst component, previously developed in Part 1 over the precursor powders, against data collected over a single-layer coated Monolith. Then, we incorporate validated kinetics for the two individual SCR and PGM components into a dual-layer ASC Monolith Catalyst model and proceed to a systematic validation against experimental catalytic activity data collected over core samples of the dual-layer ASC system. A DOE approach is also adopted in order to secure a uniform coverage of the operating field. A positive interaction of the PGM and SCR catalytic chemistries is emphasized by the data collected over the dual-layer SCR + PGM Monolith Catalyst, leading to largely enhanced N 2 selectivities as compared to a single-layer PGM-only washcoat. We show that such a beneficial interaction between the PGM and SCR chemistries occurs via diffusion/reaction of NH 3 and NO x in the SCR Catalyst layer. Results prove that the dual-layer ASC model can simulate realistically the actual NH 3 slip Catalyst configuration over a wide range of representative conditions.
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Experimental and modeling study of a dual-layer (SCR + PGM) NH3 slip Monolith Catalyst (ASC) for automotive SCR after treatment systems. Part 2. Validation of PGM kinetics and modeling of the dual-layer ASC Monolith
Applied Catalysis B-environmental, 2013Co-Authors: Massimo Colombo, Isabella Nova, Enrico Tronconi, Volker Schmeißer, Brigitte Bandl-konrad, Lisa ZimmermannAbstract:Abstract We present herein the final part in the development and validation of a chemically and physically consistent mathematical model of a commercial dual-layer (SCR + PGM) Monolithic NH 3 slip converter (ASC). Specifically, in this conclusive Part 2 of the project we first validate the global kinetic model for the PGM Catalyst component, previously developed in Part 1 over the precursor powders, against data collected over a single-layer coated Monolith. Then, we incorporate validated kinetics for the two individual SCR and PGM components into a dual-layer ASC Monolith Catalyst model and proceed to a systematic validation against experimental catalytic activity data collected over core samples of the dual-layer ASC system. A DOE approach is also adopted in order to secure a uniform coverage of the operating field. A positive interaction of the PGM and SCR catalytic chemistries is emphasized by the data collected over the dual-layer SCR + PGM Monolith Catalyst, leading to largely enhanced N 2 selectivities as compared to a single-layer PGM-only washcoat. We show that such a beneficial interaction between the PGM and SCR chemistries occurs via diffusion/reaction of NH 3 and NO x in the SCR Catalyst layer. Results prove that the dual-layer ASC model can simulate realistically the actual NH 3 slip Catalyst configuration over a wide range of representative conditions.
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experimental and modeling study of a dual layer scr pgm nh3 slip Monolith Catalyst asc for automotive scr aftertreatment systems part 1 kinetics for the pgm component and analysis of scr pgm interactions
Applied Catalysis B-environmental, 2013Co-Authors: Massimo G Colombo, Isabella Nova, Enrico Tronconi, Volker Schmeiser, Brigitte Bandlkonrad, Lisa ZimmermannAbstract:Abstract We present herein the first of two parts in the development and validation of a chemically and physically consistent mathematical model of a commercial dual-layer (SCR + PGM) Monolithic NH 3 slip converter (ASC). The overall project followed a systematic approach of growing complexity, and its results emphasize the beneficial features of a dual-layer configuration with the SCR Catalyst on top of the PGM component. Specifically, we report in this paper NH 3 /O 2 /NO NO 2 steady-state and transient kinetic runs performed over the PGM component of the dual-layer NH 3 slip Catalyst. The PGM component was tested in a representative temperature range (150–550 °C) in the form of precursor washcoat powders at high space velocities in order to gain kinetic information. From these data an original global PGM kinetic model was developed, which fully accounts for the effects of temperature and of NO 2 /NO x feed ratio (0–1) on NH 3 oxidation. The model considers NO 2 inhibition on NO oxidation, as well as a novel NO 2 inhibition effect on the NH 3 oxidation reactions. Comparative NH 3 /O 2 /NO NO 2 steady-state runs were performed also over two combinations of SCR + PGM powders (sequential double-bed and mechanical mixture). The N 2 selectivity was greater over the mechanical mixture, as in this configuration the unselective NH 3 oxidation products (NO x ) formed over the PGM Catalyst had a chance to further react selectively with NH 3 over the SCR Catalyst. Such a positive interaction between the PGM and the SCR catalytic chemistries was satisfactorily predicted by a model involving the simple superposition of the PGM and SCR kinetics. In the following part of the project the herein developed PGM kinetics, together with consistent SCR kinetics, will be incorporated in a novel dual-layer Monolith Catalyst model and validated against both lab-scale and engine test bench data collected over dual-layer ASC systems.
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Experimental and modeling study of a dual-layer (SCR + PGM) NH3 slip Monolith Catalyst (ASC) for automotive SCR aftertreatment systems. Part 1. Kinetics for the PGM component and analysis of SCR/PGM interactions
Applied Catalysis B-environmental, 2013Co-Authors: Massimo G Colombo, Isabella Nova, Enrico Tronconi, Volker Schmeißer, Brigitte Bandl-konrad, Lisa ZimmermannAbstract:Abstract We present herein the first of two parts in the development and validation of a chemically and physically consistent mathematical model of a commercial dual-layer (SCR + PGM) Monolithic NH 3 slip converter (ASC). The overall project followed a systematic approach of growing complexity, and its results emphasize the beneficial features of a dual-layer configuration with the SCR Catalyst on top of the PGM component. Specifically, we report in this paper NH 3 /O 2 /NO NO 2 steady-state and transient kinetic runs performed over the PGM component of the dual-layer NH 3 slip Catalyst. The PGM component was tested in a representative temperature range (150–550 °C) in the form of precursor washcoat powders at high space velocities in order to gain kinetic information. From these data an original global PGM kinetic model was developed, which fully accounts for the effects of temperature and of NO 2 /NO x feed ratio (0–1) on NH 3 oxidation. The model considers NO 2 inhibition on NO oxidation, as well as a novel NO 2 inhibition effect on the NH 3 oxidation reactions. Comparative NH 3 /O 2 /NO NO 2 steady-state runs were performed also over two combinations of SCR + PGM powders (sequential double-bed and mechanical mixture). The N 2 selectivity was greater over the mechanical mixture, as in this configuration the unselective NH 3 oxidation products (NO x ) formed over the PGM Catalyst had a chance to further react selectively with NH 3 over the SCR Catalyst. Such a positive interaction between the PGM and the SCR catalytic chemistries was satisfactorily predicted by a model involving the simple superposition of the PGM and SCR kinetics. In the following part of the project the herein developed PGM kinetics, together with consistent SCR kinetics, will be incorporated in a novel dual-layer Monolith Catalyst model and validated against both lab-scale and engine test bench data collected over dual-layer ASC systems.
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experimental and modelling study of a dual layer nh3 slip Monolith Catalyst for automotive scr aftertreatment systems
Topics in Catalysis, 2013Co-Authors: Isabella Nova, Massimo Colombo, Enrico Tronconi, Brigitte Bandlkonrad, Volker Schmeißer, Lisa ZimmermannAbstract:The approach to the development of a chemically and physically consistent mathematical model of ASC dual-layer (SCR + PGM) washcoated Monolith converters is herein presented. Steady-state and transient kinetic runs were performed over each one of the two ASC components (SCR and PGM) in the form of powders and also over the two mixed powdered Catalysts, thus acquiring information on the interactions between the SCR and the PGM catalytic chemistries. Global kinetic models were fitted to the SCR and to the PGM Catalyst data, and validated against experiments performed over both washcoated single-layered SCR and PGM Monoliths and over a full dual-layer ASC honeycomb Catalyst (SCR layer on top). It was found that the dual-layer (SCR + PGM) ASC architecture grants increased N2 selectivities compared to a PGM-only washcoat.
Robert J Farrauto - One of the best experts on this subject based on the ideXlab platform.
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steam reforming of ethanol on rh siceo2 washcoated Monolith Catalyst stable Catalyst performance
International Journal of Hydrogen Energy, 2018Co-Authors: Tamara Siqueira Moraes, Robert J Farrauto, Luiz E P Borges, Fabio B NoronhaAbstract:Abstract The performance of a new Rh/CeSiO2 Catalyst supported on a ceramic Monolith for steam reforming (SR) of ethanol for hydrogen generation was investigated. It provides several advantages over a traditional pellet based Catalyst in that it will reduce weight, size and pressure drop in the reactor. The effect of steam to ethanol molar ratio and temperature were first investigated on a powdered Catalyst in order to establish the preferred reaction conditions to be used for tests on the Monolith. The optimum temperature for coke free, high selectivity and stable Catalyst operation was 1073 K at a steam to ethanol molar ratio of 3.5. The Monolith supported Catalyst was evaluated for aging stability, on/off performance and coke regeneration using steam gasification. After 96 h of SR of ethanol at 1028 K and water/ethanol molar ratio of 3.5 the Monolith supported Catalyst retained stable performance throughout the entire time on stream with the only products being H2, CO, CO2. Some coke formation was observed using Raman spectra, however, it did not cause any permanent deactivation. Regeneration via steam gasification at 973 K with 20% steam in N2 was successful for coke removal and complete Catalyst regeneration.
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autothermal reforming of glycerol in a dual layer Monolith Catalyst
Chemical Engineering Science, 2013Co-Authors: Robert J Farrauto, Adeniyi LawalAbstract:Abstract The autothermal reforming (ATR) of glycerol into synthesis gas was studied using the BASF Pt and Rh/Pt dual layer Monolith Catalyst. At gas hourly space velocities of ∼10 4 h −1 , the Catalyst achieved 100% glycerol conversion to near equilibrium concentrations of H 2 , CO, CO 2 , and CH 4 . The effect of the distance between the atomizer nozzle and Catalyst on reactor performance was studied, and the optimum distance was found to be 2 in. The optimum operating conditions to produce high yields of H 2 , CO and H 2 /CO molar ratio of ∼2 with minimal coke formation were also determined to be O 2 /C of 0.15, S/C of 0.8, temperature of 650 °C and atmospheric pressure. In addition, the effect of non-catalytic reactions was studied. The results showed that the Catalyst was capable of reforming glycerol as well as the by-products from non-catalytic reaction at 600–700 °C. The Aspen simulation software package was used to calculate the equilibrium product composition for various reaction conditions. A comparison between equilibrium and experimental data was made, and the agreement was generally good indicating that close-to-equilibrium conditions were attained for the selected reaction conditions. This study is the first step in the development of a process for autothermal reforming of crude glycerol to generate synthesis gas for methanol production.
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selective co oxidation over a commercial prox Monolith Catalyst for hydrogen fuel cell applications
International Journal of Hydrogen Energy, 2012Co-Authors: Qinglin Zhang, Larry Shore, Robert J FarrautoAbstract:Abstract Preferential oxidation (PROX) of CO over noble-metal-containing Monolith Catalysts is one of the most promising approaches for removing CO to generate low temperature fuel cell quality H 2 . The Monolith-supported washcoated Catalyst comprising Cu and Fe promoted with Pt is highly effective in reducing the CO in practical reformates to less than 10 ppm over a broad range of feed compositions, inlet temperatures and turn down ratios. It is speculated that Pt dissociates the H 2 which then reduces the CuO to its active state. Pt may also act as a coCatalyst for CO adsorption with metal oxides supplying oxygen for PROX reaction. The catalytic system is operated adiabatically with an inlet temperature between roughly 65–120 °C reaching an exit temperature close to 150 °C with no evidence of reverse water gas shift or methanation. The goal was to find the proper operating conditions to achieve −1 with high steam levels of up to 45%. The wide operating window simplifies the control of the PROX reactor and improves the fuel processor’s performance for fast startup and shutdown and responses to transient loads. The Catalyst also retains its performance after multiple start and stops modes of operation in reformate.
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Selective CO oxidation over a commercial PROX Monolith Catalyst for hydrogen fuel cell applications
International Journal of Hydrogen Energy, 2012Co-Authors: Qinglin Zhang, Larry Shore, Robert J FarrautoAbstract:Preferential oxidation (PROX) of CO over noble-metal-containing Monolith Catalysts is one of the most promising approaches for removing CO to generate low temperature fuel cell quality H 2. The Monolith-supported washcoated Catalyst comprising Cu and Fe promoted with Pt is highly effective in reducing the CO in practical reformates to less than 10 ppm over a broad range of feed compositions, inlet temperatures and turn down ratios. It is speculated that Pt dissociates the H 2 which then reduces the CuO to its active state. Pt may also act as a coCatalyst for CO adsorption with metal oxides supplying oxygen for PROX reaction. The catalytic system is operated adiabatically with an inlet temperature between roughly 65-120 ??C reaching an exit temperature close to 150 ??C with no evidence of reverse water gas shift or methanation. The goal was to find the proper operating conditions to achieve
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auto thermal and dry reforming of landfill gas over a rh γal2o3 Monolith Catalyst
Applied Catalysis B-environmental, 2010Co-Authors: Mckenzie P Kohn, Marco J Castaldi, Robert J FarrautoAbstract:Abstract Auto-thermal and dry reforming of methane and carbon dioxide mixtures was investigated experimentally at temperatures between 300 °C and 800 °C at atmospheric pressures using a Rh/γAl2O3 Monolith Catalyst. CH4:CO2 ratios of 1:1 and 1.4:1 were tested. The Rh Catalyst reached equilibrium conversions of CH4 and CO2 to H2 and CO for both CH4:CO2 ratios. Equilibrium analysis shows that carbon formation is likely for dry reforming but not for auto-thermal reforming. Experimentally, carbon formation was seen after long-term exposure to 1.4:1 CH4:CO2 ratios without oxygen, but the Catalyst has shown the ability to be regenerated in air. Auto-thermal tests, with and without external heat input, operating at an equivalence ratio of 4.3 (O2:CH4 = 0.46) and maintaining the CH4:CO2 ratio of either 1:1 or 1.4:1, did not show signs of carbon formation or deactivation. ATR experiments resulted in H2:CO ratios between 1.0 and 2.0 that can be tuned depending on the Monolith temperature, beneficial in the case of downstream Fischer–Tropsch processes. For the auto-thermal experiments, theoretical reaction extents were calculated based on experimental data and showed two primary regimes in Catalyst operation: a CH4 combustion and partial oxidation regime, and reforming and water–gas shift regime.
Xiaotong Li - One of the best experts on this subject based on the ideXlab platform.
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a highly stable pd sio2 cordierite Monolith Catalyst for 2 ethyl anthraquinone hydrogenation
RSC Advances, 2015Co-Authors: Xiaotong Li, Hongjiu Su, Shudong WangAbstract:Catalyst stability is an urgent issue for ethyl-anthraquinone (EAQ) hydrogenation to produce the environment friendly oxidant H2O2. Herein, a highly stable egg-shell Pd/SiO2/cordierite Monolith Catalyst (PSC) was prepared by an impregnation method. For comparison, a Pd/Al2O3/cordierite Monolithic Catalyst (PAC) was also prepared. The stability tests of the Catalysts were conducted in a continuous trickle bed reactor at 40 °C with a high liquid space velocity of 25 h−1. It turned out that the PSC Catalyst obtained a stable H2O2 yield in the 1000 h test while the PAC Catalyst deactivated in 100 h. The as-prepared Catalysts were characterized by X-ray diffraction (XRD), N2 adsorption, NH3 temperature programmed desorption (NH3-TPD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), H2 temperature programmed reduction (H2-TPR) and X-ray photoelectron spectroscopy (XPS). N2 adsorption and NH3-TPD results showed that the PSC Catalyst had a regular structure and very weak acidity, which contributed to improving the Catalyst selectivity and stability. Besides, the lower support calcination temperature was found to be beneficial to improving the hydrogenation efficiency because of higher Pd dispersion and lower Pd loss.
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A highly stable Pd/SiO2/cordierite Monolith Catalyst for 2-ethyl-anthraquinone hydrogenation
RSC Advances, 2015Co-Authors: Xiaotong Li, Hongjiu Su, Shudong WangAbstract:Catalyst stability is an urgent issue for ethyl-anthraquinone (EAQ) hydrogenation to produce the environment friendly oxidant H2O2. Herein, a highly stable egg-shell Pd/SiO2/cordierite Monolith Catalyst (PSC) was prepared by an impregnation method. For comparison, a Pd/Al2O3/cordierite Monolithic Catalyst (PAC) was also prepared. The stability tests of the Catalysts were conducted in a continuous trickle bed reactor at 40 °C with a high liquid space velocity of 25 h−1. It turned out that the PSC Catalyst obtained a stable H2O2 yield in the 1000 h test while the PAC Catalyst deactivated in 100 h. The as-prepared Catalysts were characterized by X-ray diffraction (XRD), N2 adsorption, NH3 temperature programmed desorption (NH3-TPD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), H2 temperature programmed reduction (H2-TPR) and X-ray photoelectron spectroscopy (XPS). N2 adsorption and NH3-TPD results showed that the PSC Catalyst had a regular structure and very weak acidity, which contributed to improving the Catalyst selectivity and stability. Besides, the lower support calcination temperature was found to be beneficial to improving the hydrogenation efficiency because of higher Pd dispersion and lower Pd loss.