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Prenesti G, Azzato G, Cassano K, De Marco G, Caravella A. Assessment of effectiveness factor in porous catalysts under non-symmetric external conditions of concentration. INTERNATIONAL JOURNAL OF CHEMICAL REACTOR ENGINEERING 2022. [DOI: 10.1515/ijcre-2022-0143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
the present paper, the effectiveness factor of porous catalytic particles is evaluated in the absence of boundary conditions symmetry over the external surface by computational fluid dynamic (CFD) techniques. The first-order kinetics of decane oxidation, already evaluated experimentally, is taken as a representative reaction. Our study arises from the fact that, in the open literature, the effectiveness factor is usually calculated considering conditions of symmetry of concentration field around particles. However, depending on the fluid dynamics of the system, such conditions are not always established and, thus, our work aims at studying for the first time the behaviour of particle catalysts with non-uniform concentration fields over the surface. In particular, the effectiveness factor of the particles in a catalytic layer is calculated in the absence of symmetry by changing several parameters (temperature, tortuosity and mean pore diameter of particle) using two different methods, named Sphere-by-Sphere (SbS) and Equisized-Volume (EV), respectively. The results of these two methods are then compared to the theoretical one obtained in the presence of spherical symmetry. As a main result, we found that, for moderately low values of Thiele modulus (<1.3 ca.), the analytical expression of the effectiveness factor obtained under spherical symmetry can be also applied in non-symmetric conditions. On the contrary, this cannot be done for higher values of Thiele modulus, for which we propose an empirical correlation of the effectiveness factor based on a corrected Thiele modulus. The efficacy of our approach is stated by the fact that pseudo-homogeneous-mode simulations of the heterogeneous system show results that match very well those obtained in heterogeneous mode, with an important reduction of calculation time and memory. The presented methodology can be also applied to n-order kinetics.
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Affiliation(s)
- Giuseppe Prenesti
- Department of Computer Engineering, Modelling, Electronics and Systems Engineering (DIMES) , University of Calabria , Via P. Bucci, Cubo 42C, 87036 (CS) , Rende , Italy
| | - Giulia Azzato
- Department of Computer Engineering, Modelling, Electronics and Systems Engineering (DIMES) , University of Calabria , Via P. Bucci, Cubo 42C, 87036 (CS) , Rende , Italy
| | - Katia Cassano
- Department of Computer Engineering, Modelling, Electronics and Systems Engineering (DIMES) , University of Calabria , Via P. Bucci, Cubo 42C, 87036 (CS) , Rende , Italy
| | - Giuseppe De Marco
- Information Technology Center (ICT) , University of Calabria , Via P. Bucci, Cubo 22B, 87036 (CS) , Rende , Italy
| | - Alessio Caravella
- Department of Computer Engineering, Modelling, Electronics and Systems Engineering (DIMES) , University of Calabria , Via P. Bucci, Cubo 42C, 87036 (CS) , Rende , Italy
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Uchisawa J, Tango T, Caravella A, Hara S, Haneda M, Murakami T, Nakagawa H, Nanba T, Obuchi A. Effects of the Extent of Silica Doping and the Mesopore Size of an Alumina Support on Activity as a Diesel Oxidation Catalyst. Ind Eng Chem Res 2014. [DOI: 10.1021/ie5005724] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Junko Uchisawa
- Energy
Technology Research Institute, Engine Combustion and Emission Control
Group, National Institute of Advanced Industrial Science and Technology (AIST), 16-1 Onogawa, Tsukuba 305-8569, Japan
| | - Takeru Tango
- Research
and Development Department, Mizusawa Industrial Chemicals Ltd., 1-1 Mizusawa, Tainai 959-2638, Japan
| | - Alessio Caravella
- Research
Institute for Innovation in Sustainable Chemistry, Membrane Separation
Processes Group, National Institute of Advanced Industrial
Science and Technology (AIST) , Central
5, 1-1-1 Higashi, Tsukuba 305-8565, Japan
| | - Shigeki Hara
- Research
Institute for Innovation in Sustainable Chemistry, Membrane Separation
Processes Group, National Institute of Advanced Industrial
Science and Technology (AIST) , Central
5, 1-1-1 Higashi, Tsukuba 305-8565, Japan
| | - Masaaki Haneda
- Advanced
Ceramics Research Center, Nagoya Institute of Technology, 10-6-29
Asahigaoka, Tajimi, Gifu 507-0071, Japan
| | - Tatsuro Murakami
- Research
and Development Department, Mizusawa Industrial Chemicals Ltd., 1-1 Mizusawa, Tainai 959-2638, Japan
| | - Hideyuki Nakagawa
- Research
and Development Department, Mizusawa Industrial Chemicals Ltd., 1-1 Mizusawa, Tainai 959-2638, Japan
| | - Tetsuya Nanba
- Fukushima
Renewable Energy Institute, Hydrogen Energy Carrier Team, National Institute of Advanced Industrial Science and Technology (AIST), 2-2-9 Machiikedai, Kouriyama 963-0215, Japan
| | - Akira Obuchi
- Energy
Technology Research Institute, Engine Combustion and Emission Control
Group, National Institute of Advanced Industrial Science and Technology (AIST), 16-1 Onogawa, Tsukuba 305-8569, Japan
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