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Sulfur - functionalization of porous silica particles and application to mercury vapor sorption / Noah D. Meeks in Industrial & engineering chemistry research, Vol. 49 N° 10 (Mai 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 10 (Mai 2010) . - pp. 4687–4693 Titre : Sulfur - functionalization of porous silica particles and application to mercury vapor sorption Type de document : texte imprimé Auteurs : Noah D. Meeks, Auteur ; Stephen Rankin, Auteur ; Dibakar Bhattacharyya, Auteur Année de publication : 2010 Article en page(s) : pp. 4687–4693 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Porous  Silica  Particles Résumé : Silanol (SiOH) groups on silica particle surfaces undergo silylation reactions with organosilane molecules to give functionalized particles, which are used in many applications. The determination of the extent of this reaction is important for proper design of functionalized materials, depending upon the application. Two types of porous silica particles (206 and 484 m2 g−1; 9.6 and 2.9 nm average pore diameter, respectively), and colloidal silica (Ludox) with a nonporous base particle of 22 nm diameter, were functionalized with sulfur-containing silanes, 3-mercaptopropyl trimethoxy silane (MPTMS), and bis[3-(triethoxysilyl) propyl]-tetrasulfide (S4). Maximum extent of functionalization was determined with S4 using Fourier transform infrared spectrometry (FTIR), thermogravimetric analysis (TGA), and total S analysis. For the two types of porous silica particles, FTIR indicated that 54 and 17% of the silanol groups were functionalized with S4, and TGA indicated that the functionalized particles were 12 and 11 mass % MPTMS, respectively. These results were independently confirmed with total sulfur analysis. Extents of functionalization were determined for varying the silane structure on the same silica particle. MPTMS reacted with 38% of functional groups, while S4 reacted with 17%; the mass % of silane is the same regardless of silane structure on the same silica particle. Characterization by DSC indicated a glass transition occurs in the silane layer of the S4-functionalized silica at about 85 °C, but not in the MPTMS functionalized particles. Finally, mercury sorption breakthrough curves indicate the pore characteristics of the S4 functionalized samples. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901580k [article] Sulfur - functionalization of porous silica particles and application to mercury vapor sorption [texte imprimé] / Noah D. Meeks, Auteur ; Stephen Rankin, Auteur ; Dibakar Bhattacharyya, Auteur . - 2010 . - pp. 4687–4693. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 10 (Mai 2010) . - pp. 4687–4693 Mots-clés : Porous  Silica  Particles Résumé : Silanol (SiOH) groups on silica particle surfaces undergo silylation reactions with organosilane molecules to give functionalized particles, which are used in many applications. The determination of the extent of this reaction is important for proper design of functionalized materials, depending upon the application. Two types of porous silica particles (206 and 484 m2 g−1; 9.6 and 2.9 nm average pore diameter, respectively), and colloidal silica (Ludox) with a nonporous base particle of 22 nm diameter, were functionalized with sulfur-containing silanes, 3-mercaptopropyl trimethoxy silane (MPTMS), and bis[3-(triethoxysilyl) propyl]-tetrasulfide (S4). Maximum extent of functionalization was determined with S4 using Fourier transform infrared spectrometry (FTIR), thermogravimetric analysis (TGA), and total S analysis. For the two types of porous silica particles, FTIR indicated that 54 and 17% of the silanol groups were functionalized with S4, and TGA indicated that the functionalized particles were 12 and 11 mass % MPTMS, respectively. These results were independently confirmed with total sulfur analysis. Extents of functionalization were determined for varying the silane structure on the same silica particle. MPTMS reacted with 38% of functional groups, while S4 reacted with 17%; the mass % of silane is the same regardless of silane structure on the same silica particle. Characterization by DSC indicated a glass transition occurs in the silane layer of the S4-functionalized silica at about 85 °C, but not in the MPTMS functionalized particles. Finally, mercury sorption breakthrough curves indicate the pore characteristics of the S4 functionalized samples. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901580k