The Contribution of Molecular Diffusion in Silica Coating and Chemical Reaction in the Overall Rate of Reaction of Aluminum Hydroxide with Fluosilicic Acid
The kinetic of the heterogeneous chemical reaction of aluminum hydroxide and fluosilicic acid was studied. It was found that the diffusion of the reactants through the porous silica coating to the aluminum hydroxide surface and the interfacial chemical reaction between the diffusing reactant and alu...
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| Format: | Article |
| Language: | English |
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Iranian Institute of Research and Development in Chemical Industries (IRDCI)-ACECR
2005-12-01
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| Series: | Iranian Journal of Chemistry & Chemical Engineering |
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| Online Access: | http://www.ijcce.ac.ir/article_8104_9fe01a73bd871b55d3e0c4b7a57d338c.pdf |
| _version_ | 1818275999776768000 |
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| author | Mahmoud Bayat Abbas Taeb Saeed Rastegar |
| author_facet | Mahmoud Bayat Abbas Taeb Saeed Rastegar |
| author_sort | Mahmoud Bayat |
| collection | DOAJ |
| description | The kinetic of the heterogeneous chemical reaction of aluminum hydroxide and fluosilicic acid was studied. It was found that the diffusion of the reactants through the porous silica coating to the aluminum hydroxide surface and the interfacial chemical reaction between the diffusing reactant and aluminum hydroxide platelets control the overall reaction rate. These two phenomena were studied and their contributions to the overall reaction rate were derived using experimental data. By combining these terms a relation for the overall reaction rate was obtained. The activation energy of the chemical reaction was calculated to be 12 kcal/mol and the activation energy of the diffusion into the silica coating was found as 28 kcal/mol. A numerical procedure was adjusted to determine the variation of the specific surface area of un-reacted core, its average particle size and the specific surface area for mass transfer |
| first_indexed | 2024-12-12T22:38:41Z |
| format | Article |
| id | doaj.art-5a658e47446448868360fc3ce3d66e8b |
| institution | Directory Open Access Journal |
| issn | 1021-9986 1021-9986 |
| language | English |
| last_indexed | 2024-12-12T22:38:41Z |
| publishDate | 2005-12-01 |
| publisher | Iranian Institute of Research and Development in Chemical Industries (IRDCI)-ACECR |
| record_format | Article |
| series | Iranian Journal of Chemistry & Chemical Engineering |
| spelling | doaj.art-5a658e47446448868360fc3ce3d66e8b2022-12-22T00:09:23ZengIranian Institute of Research and Development in Chemical Industries (IRDCI)-ACECRIranian Journal of Chemistry & Chemical Engineering1021-99861021-99862005-12-0124415248104The Contribution of Molecular Diffusion in Silica Coating and Chemical Reaction in the Overall Rate of Reaction of Aluminum Hydroxide with Fluosilicic AcidMahmoud Bayat0Abbas Taeb1Saeed Rastegar2Faculty of Chemical Engineering, Iran University of Science and Technology, P.O.Box 16765-163, Tehran, I.R.IRANFaculty of Chemical Engineering, Iran University of Science and Technology, P.O.Box 16765-163, Tehran, I.R.IRANFaculty of Polymer, Amirkabir University of Technology, P.O.Box 15875-4413, Tehran, I.R.IRANThe kinetic of the heterogeneous chemical reaction of aluminum hydroxide and fluosilicic acid was studied. It was found that the diffusion of the reactants through the porous silica coating to the aluminum hydroxide surface and the interfacial chemical reaction between the diffusing reactant and aluminum hydroxide platelets control the overall reaction rate. These two phenomena were studied and their contributions to the overall reaction rate were derived using experimental data. By combining these terms a relation for the overall reaction rate was obtained. The activation energy of the chemical reaction was calculated to be 12 kcal/mol and the activation energy of the diffusion into the silica coating was found as 28 kcal/mol. A numerical procedure was adjusted to determine the variation of the specific surface area of un-reacted core, its average particle size and the specific surface area for mass transferhttp://www.ijcce.ac.ir/article_8104_9fe01a73bd871b55d3e0c4b7a57d338c.pdfheterogeneous reactionaluminum hydroxidefluosilicic acidaluminum fluoridesilicaeffective diffusion coefficientaggregationkinetics |
| spellingShingle | Mahmoud Bayat Abbas Taeb Saeed Rastegar The Contribution of Molecular Diffusion in Silica Coating and Chemical Reaction in the Overall Rate of Reaction of Aluminum Hydroxide with Fluosilicic Acid Iranian Journal of Chemistry & Chemical Engineering heterogeneous reaction aluminum hydroxide fluosilicic acid aluminum fluoride silica effective diffusion coefficient aggregation kinetics |
| title | The Contribution of Molecular Diffusion in Silica Coating and Chemical Reaction in the Overall Rate of Reaction of Aluminum Hydroxide with Fluosilicic Acid |
| title_full | The Contribution of Molecular Diffusion in Silica Coating and Chemical Reaction in the Overall Rate of Reaction of Aluminum Hydroxide with Fluosilicic Acid |
| title_fullStr | The Contribution of Molecular Diffusion in Silica Coating and Chemical Reaction in the Overall Rate of Reaction of Aluminum Hydroxide with Fluosilicic Acid |
| title_full_unstemmed | The Contribution of Molecular Diffusion in Silica Coating and Chemical Reaction in the Overall Rate of Reaction of Aluminum Hydroxide with Fluosilicic Acid |
| title_short | The Contribution of Molecular Diffusion in Silica Coating and Chemical Reaction in the Overall Rate of Reaction of Aluminum Hydroxide with Fluosilicic Acid |
| title_sort | contribution of molecular diffusion in silica coating and chemical reaction in the overall rate of reaction of aluminum hydroxide with fluosilicic acid |
| topic | heterogeneous reaction aluminum hydroxide fluosilicic acid aluminum fluoride silica effective diffusion coefficient aggregation kinetics |
| url | http://www.ijcce.ac.ir/article_8104_9fe01a73bd871b55d3e0c4b7a57d338c.pdf |
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