@article { ISI:000237835100010, title = {Adsorption of octadecyltrichlorosilane on mesoporous SBA-15}, journal = {Applied Surface Science}, volume = {252}, number = {12}, year = {2006}, month = {APR}, pages = {4097-4103}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Adsorption of octadecyltrichlorosilane (OTS) on mesoporous SBA-15 has been studied by using Brunauer-Emmett-Teller (BET) surface area analysis, scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and thermo-gravimetric analysis (TGA) techniques. BET surface area analysis shows decrease of surface area from 930 to 416 m(2)/g after OTS adsorption. SEM pictures show close attachment of SBA-15 particles. EDAX measurements show increase of carbon weight percentage and decrease of oxygen and silicon weight percentage. XPS results closely support EDAX analysis. FTIR spectra shows presence of methyl (-CH3) and methylene (-CH2) bands and oriented OTS monolayer on SBA-15. Thermo-gravimetric analysis shows that the OTS adsorbed on SBA-15 are stable up to a temperature of 230 degrees C and that the OTS monolayers decompose between 230 and 400 degrees C. (c) 2005 Elsevier B.V. All rights reserved.

}, keywords = {Adsorption, OTS, SBA-15, Self-assembly, thermal stability}, issn = {0169-4332}, doi = {10.1016/j.apsusc.2005.06.009}, author = {Mirji, S. A. and Halligudi, Shivaraj B. and Sawant, Dhanashri P. and Jacob, Nalini E. and Patil, K. R. and Gaikwad, A. B. and Pradhan, S. D.} } @article { ISI:000249949800020, title = {Catalytic performances of silicotungstic acid/zirconia supported SBA-15 in an esterification of benzyl alcohol with acetic acid}, journal = {Journal of Molecular Catalysis A-Chemical }, volume = {276 }, number = {1-2}, year = {2007}, month = {OCT}, pages = {150-157}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Liquid phase esterification of benzyl alcohol (BA) to benzyl acetate (Peach fragrance) with an acetic acid (AA) has been investigated with 12-silicotungstic acid supported on zirconia embedded inside SBA-15 (STA/ZrO2/SBA- 15) as the catalyst. Catalysts were unambiguously characterized by XRD, N-2 adsorption-desorption, FF-IR pyridine adsorption techniques and the total amount of acidity of different STA loaded catalysts was estimated by TPD of NH3. The optimization of reaction conditions of an esterification of BA with AA was performed with 15 wt.\% STA/22.4 wt.\% ZrO2/SBA-15 calcined at 1123 K by varying catalyst concentration (1-10 wt.\% of reaction mixture); temperature, 353-383 K and AA:BA molar ratio as 0.5-3. The 15 wt.\% STA/22.4 wt.\% ZrO2/SBA-15 calcined at 1123 K was found to have the highest acidity and more active in the reaction. Under the optimized reaction conditions, the 15 wt.\% STA/22.4 wt.\%ZrO2/SBA-15 calcined at 1123 K gave 59\% BA conversion with selectivity for benzyl acetate as high as 96\% within 2 h of reaction time. (c) 2007 Elsevier B.V. All rights reserved.

}, keywords = {12-silicotungstic acid, Benzyl acetate, Benzyl alcohol, Esterification, SBA-15}, issn = {1381-1169}, doi = {10.1016/j.molcata.2007.07.001}, author = {Sawant, Dhanashri P. and Vinu, A. and Justus, Josena and Srinivasu, P. and Halligudi, Shivaraj B.} } @article { ISI:000246727900022, title = {Effect of pretreatment conditions on the catalytic activity of nano-sized TPA/ZrO2 dispersed in SBA-15 channels in acetylation reactions}, journal = {Microporous and Mesoporous Materials}, volume = {102}, number = {1-3}, year = {2007}, month = {MAY}, pages = {223-233}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Acetylation of an aromatic compounds such as veratrole (1,2-dimethoxybenzene), anisole, thioanisole, isobutyl benzene and 2-methoxynaphthalene with acetic anhydride has been investigated over a nano-sized 12-tungstophosphoric acid (TPA)/22.4 wt.\%ZrO2/SBA- 15 catalysts in the liquid phase conditions. Catalysts with different (\%) TPA and zirconia loadings calcined at different temperatures were prepared by wet-impregnation and characterized by XRD, N-2 adsorption-desorption, FT-Rarnan, X-ray photoelectron spectroscopy (XPS). The acidic behavior of the catalyst was studied by TPD of ammonia and FT-IR pyridine adsorption. Among the catalysts, 15 wt.\%TPA/22.4 wt.\%ZrO2/SBA- 15 calcined at 1123 K had the highest acidity and was the most active catalyst in veratrole acetylation with acetic anhydride. (C) 2007 Elsevier Inc. All rights reserved.

}, keywords = {acetylation, SBA-15, TPA/ZrO2, veratrole, wet-impregnation}, issn = {1387-1811}, doi = {10.1016/j.micromeso.2006.12.046}, author = {Sawant, Dhanashri P. and Hartmann, Martin and Halligudi, Shivaraj B.} }