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Preparation of pseudoboehmite with a large pore volume and a large pore size by using a membrane-dispersion microstructured reactor through the reaction of CO2 and a NaAlO2 solution / Yujun Wang in Industrial & engineering chemistry research, Vol. 50 N° 7 (Avril 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 7 (Avril 2011) . - pp. 3889–3894 Titre : Preparation of pseudoboehmite with a large pore volume and a large pore size by using a membrane-dispersion microstructured reactor through the reaction of CO2 and a NaAlO2 solution Type de document : texte imprimé Auteurs : Yujun Wang, Auteur ; Dengqing Xu, Auteur ; Haitao Sun, Auteur Année de publication : 2011 Article en page(s) : pp. 3889–3894 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Membrane  dispersion  microstructured  reactor Résumé : In this work, a membrane-dispersion microstructured reactor was specially designed to prepare PB (pseudoboehmite) with a large pore volume and a large pore size through the reaction of CO2 and an aqueous solution of NaAlO2. Tiny crystals of PB and a suitable template are necessary for generating large pore diameter and large pore volume. In this reactor, the tiny crystals could be obtained by increasing the mass transfer rate between the gas phase and the liquid phase through dispersing the CO2 gas into many microbubbles, and these microbubbles could act as a template to increase the pore volume. The effects of the final pH of the aqueous solution, the concentrations of raw materials, and the flow rate of the gas phase on pore properties of products were investigated. The results showed that when the final pH of the aqueous solution was between 10.5 and 9.4, pure PB could be obtained, and the crystal size of PB was about 2.3 nm. In addition, the specific surface area, the pore volume, and the average pore diameter of PB reached 548.5 m2/g, 2.22 mL/g, and 16.2 nm, respectively, under optimal conditions; these values were much higher than those prepared in the stirred tank. After calcinations of PB at 550 °C, the γ -Al2O3 powder obtained also yielded large pore volume and large average pore diameter. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie101629g [article] Preparation of pseudoboehmite with a large pore volume and a large pore size by using a membrane-dispersion microstructured reactor through the reaction of CO2 and a NaAlO2 solution [texte imprimé] / Yujun Wang, Auteur ; Dengqing Xu, Auteur ; Haitao Sun, Auteur . - 2011 . - pp. 3889–3894. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 7 (Avril 2011) . - pp. 3889–3894 Mots-clés : Membrane  dispersion  microstructured  reactor Résumé : In this work, a membrane-dispersion microstructured reactor was specially designed to prepare PB (pseudoboehmite) with a large pore volume and a large pore size through the reaction of CO2 and an aqueous solution of NaAlO2. Tiny crystals of PB and a suitable template are necessary for generating large pore diameter and large pore volume. In this reactor, the tiny crystals could be obtained by increasing the mass transfer rate between the gas phase and the liquid phase through dispersing the CO2 gas into many microbubbles, and these microbubbles could act as a template to increase the pore volume. The effects of the final pH of the aqueous solution, the concentrations of raw materials, and the flow rate of the gas phase on pore properties of products were investigated. The results showed that when the final pH of the aqueous solution was between 10.5 and 9.4, pure PB could be obtained, and the crystal size of PB was about 2.3 nm. In addition, the specific surface area, the pore volume, and the average pore diameter of PB reached 548.5 m2/g, 2.22 mL/g, and 16.2 nm, respectively, under optimal conditions; these values were much higher than those prepared in the stirred tank. After calcinations of PB at 550 °C, the γ -Al2O3 powder obtained also yielded large pore volume and large average pore diameter. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie101629g