CFD Simulations of Copper-Ceria Based Microreactor for COPROX
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Paola Sabrina Barbato
Abstract
A CFD model of a copper-ceria based micro-reactor for the CO preferential oxidation reaction is developed. Simulations are performed by changing the thermal conductivity of the support and the oxygen inlet concentration. It is found that the value of the wall thermal conductivity has a significant role on the temperature profiles, hot-spot and selectivity. On increasing the O2 content, the CO selectivity decreases. An increase of the oxygen content anticipates the activation of the H2 oxidation, thus competing with CO oxidation. Conversely, at low values of the O2 content, the H2 oxidation is activated only after an almost complete CO oxidation is obtained. From the results it appears that the temperature control and management in the reactor is a key for increasing the CO selectivity at high CO conversion.
Acknowledgements
This work was financially supported by Italian MIUR (FIRB2010 “Futuro in Ricerca”, project n° RBFR10S4OW).
Nomenclature
| cp | [kJ kg–1K–1] | specific heat at constant pressure |
| d | [μm] | channel diameter |
| dw | [μm] | wall thickness |
| E | [J mol–1] | activation energy |
| hc | [W m–2K–1] | exterior convective heat transfer coefficient |
| h | [kJ kg–1] | specific enthalpy |
| Hi0 | [kJ kg–1] | standard enthalpy of formation |
| Jz,i | [kg m–2 s–1] | Diffusive mass fluxes of the i-th specie |
| L | [m] | channel length |
| Ns | [-] | Number of species |
| p | [Pa] | pressure |
| r | [μm] | channel radial variable |
| R | [J K–1 mol–1] | universal gas constant |
| Sc | [-] | Schmidt number |
| Sco | [-] | CO selectivity |
| T | [K] | temperature |
| T∞ | [K] | external temperature |
| u,v | [m s–1] | axial and radial velocity components |
| y | [-] | mole fraction |
| z | [μm] | channel axial variable |
Greek letters
| α, β,γ | [-] | apparent reaction order |
| λ | [W m–1K–1] | thermal conductivity |
| μ | [Pa s] | dynamic viscosity |
| ρ | [kg·m–3] | gas density |
| τ | [Pa] | shear stress |
| ωy,I | [mol·h–1·g–1] | reaction rate |
| ωh | [kJ·m–3·h–1] | heat surface production rate |
Subscripts and superscripts
| b | bulk |
| in | inlet |
| w | wall |
| max | maximum |
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©2016 by De Gruyter
Artikel in diesem Heft
- Frontmatter
- Preface to the Special Issue dedicated to the First International Energy Conference, IEC 2015
- Derivation of an Upscaled Model for Mass Transfer and Reaction for Non-Food Starch Conversion to Bioethanol
- Elucidating Kinetic, Adsorption and Partitioning Phenomena from a Single Well Tracer Method: Laboratory and Bench Scale Studies
- Thermodynamic Analysis of Ethanol Synthesis from Glycerol by Two-Step Reactor Sequence
- Modeling the Transient VOC (toluene) Oxidation in a Packed-Bed Catalytic Reactor
- Substrate Feeding Strategy Integrated with a Biomass Bayesian Estimator for a Biotechnological Process
- Comparison Tools for Parametric Identification of Kinetic Model for Ethanol Production using Evolutionary Optimization Approach
- Hydrodeoxygenation of Phenol Over Sulfided CoMo Catalysts Supported on a Mixed Al2O3-TiO2 Oxide
- Experimental and Computational Analysis of Single Phase Flow Coiled Flow Inverter Focusing on Number of Transfer Units and Effectiveness
- Dynamic Effectiveness Factor for Catalytic Particles with Anomalous Diffusion
- Experimental and Artificial Neural Network Modeling of a Upflow Anaerobic Contactor (UAC) for Biogas Production from Vinasse
- Novel Feedback Control to Improve Biohydrogen Production by Desulfovibrio alaskensis
- Influence of an Alkaline Zeolite on the Carbon Flow in Anaerobiosis of Three Strains of Saccharomyces cerevisiae
- CCS, A Needed Technology for the Mexican Electrical Sector: Sustainability and Local Industry Participation
- Olefins and Ethanol from Polyolefins: Analysis of Potential Chemical Recycling of Poly(ethylene) Mexican Case
- CFD Simulations of Copper-Ceria Based Microreactor for COPROX
Artikel in diesem Heft
- Frontmatter
- Preface to the Special Issue dedicated to the First International Energy Conference, IEC 2015
- Derivation of an Upscaled Model for Mass Transfer and Reaction for Non-Food Starch Conversion to Bioethanol
- Elucidating Kinetic, Adsorption and Partitioning Phenomena from a Single Well Tracer Method: Laboratory and Bench Scale Studies
- Thermodynamic Analysis of Ethanol Synthesis from Glycerol by Two-Step Reactor Sequence
- Modeling the Transient VOC (toluene) Oxidation in a Packed-Bed Catalytic Reactor
- Substrate Feeding Strategy Integrated with a Biomass Bayesian Estimator for a Biotechnological Process
- Comparison Tools for Parametric Identification of Kinetic Model for Ethanol Production using Evolutionary Optimization Approach
- Hydrodeoxygenation of Phenol Over Sulfided CoMo Catalysts Supported on a Mixed Al2O3-TiO2 Oxide
- Experimental and Computational Analysis of Single Phase Flow Coiled Flow Inverter Focusing on Number of Transfer Units and Effectiveness
- Dynamic Effectiveness Factor for Catalytic Particles with Anomalous Diffusion
- Experimental and Artificial Neural Network Modeling of a Upflow Anaerobic Contactor (UAC) for Biogas Production from Vinasse
- Novel Feedback Control to Improve Biohydrogen Production by Desulfovibrio alaskensis
- Influence of an Alkaline Zeolite on the Carbon Flow in Anaerobiosis of Three Strains of Saccharomyces cerevisiae
- CCS, A Needed Technology for the Mexican Electrical Sector: Sustainability and Local Industry Participation
- Olefins and Ethanol from Polyolefins: Analysis of Potential Chemical Recycling of Poly(ethylene) Mexican Case
- CFD Simulations of Copper-Ceria Based Microreactor for COPROX
