<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Devassy, Biju M.</style></author><author><style face="normal" font="default" size="100%">Shanbhag, G. V.</style></author><author><style face="normal" font="default" size="100%">Mirajkar, Subhash P.</style></author><author><style face="normal" font="default" size="100%">Bohringer, Walter</style></author><author><style face="normal" font="default" size="100%">Fletcher, Jack C. Q.</style></author><author><style face="normal" font="default" size="100%">Halligudi, Shivaraj B.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Silicotungstate-modified zirconia as an efficient catalyst for phenol tert-butylation</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Molecular Catalysis A-Chemical</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">phenol</style></keyword><keyword><style  face="normal" font="default" size="100%">Silicotungstic acid</style></keyword><keyword><style  face="normal" font="default" size="100%">tert-butylation</style></keyword><keyword><style  face="normal" font="default" size="100%">Zirconia</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2005</style></year><pub-dates><date><style  face="normal" font="default" size="100%">MAY</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">1-2</style></number><publisher><style face="normal" font="default" size="100%">ELSEVIER SCIENCE BV</style></publisher><pub-location><style face="normal" font="default" size="100%">PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS</style></pub-location><volume><style face="normal" font="default" size="100%">233</style></volume><pages><style face="normal" font="default" size="100%">141-146</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;The alkylation of phenol with tert-butanol was investigated using zirconia modified with silicotungstic acid (STA) as catalysts. The catalysts with different STA loading (5-25 wt.% calcined at 750 degrees C) and calcination temperature (15 wt.% calcined from 350 to 850 degrees C) were prepared and characterized by X-ray diffraction and NH3-TPD measurements. The XRD results indicate that STA stabilizes the tetragonal phase of zirconia. The catalyst with 15% STA on ZrO2 calcined at 750 degrees C shows the highest acidity and hence highest activity. Under the reaction conditions of 140 degrees C, tert-butanol/phenol molar ratio of 2 and LHSV of 4 h(-1), phenol conversion was 95.4% with selectivity to 2-tert-butyl phenol 4.3%, 4-tert-butyl phenol 59.2% and 2,4-di-tert-butyl phenol 35.8%. The reaction was studied as a function of time for 50 It without appreciable change in phenol conversion and product selectivity. The deactivated catalyst could be regenerated by calcination with out appreciable lose in catalytic activity and product selectivity. (c) 2005 Elsevier B.V. All rights reserved.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">1-2</style></issue><work-type><style face="normal" font="default" size="100%">Article</style></work-type><custom3><style face="normal" font="default" size="100%">Foreign</style></custom3><custom4><style face="normal" font="default" size="100%">3.958</style></custom4></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Devassy, Biju M.</style></author><author><style face="normal" font="default" size="100%">Halligudi, Shivaraj B.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Effect of calcination temperature on the catalytic activity of zirconia-supported heteropoly acids</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Molecular Catalysis A-Chemical</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Acylation</style></keyword><keyword><style  face="normal" font="default" size="100%">Alkylation</style></keyword><keyword><style  face="normal" font="default" size="100%">Anisole</style></keyword><keyword><style  face="normal" font="default" size="100%">diphenylether</style></keyword><keyword><style  face="normal" font="default" size="100%">Phosphotungstic acid</style></keyword><keyword><style  face="normal" font="default" size="100%">Silicotungstic acid</style></keyword><keyword><style  face="normal" font="default" size="100%">veratrole</style></keyword><keyword><style  face="normal" font="default" size="100%">Zirconia</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">JUL</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">1-2</style></number><publisher><style face="normal" font="default" size="100%">ELSEVIER SCIENCE BV</style></publisher><pub-location><style face="normal" font="default" size="100%">PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS</style></pub-location><volume><style face="normal" font="default" size="100%">253</style></volume><pages><style face="normal" font="default" size="100%">8-15</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Zirconia-supported silicotungstic acid (15% STA) catalyst with different calcination temperatures (600-850 degrees C) was prepared by suspending zirconium oxyhydroxide in methanol solution of STA followed by drying and calcination. These catalysts were characterized by XRD, FTIR pyridine adsorption and DRUV-vis spectroscopy. The catalysts showed both Bronsted as well as Lewis acidity and 15% STA on zirconia calcined at 750 degrees C (15 SZ-750) had the highest Bronsted acidity. Characterization of 15 SZ-750 catalyst by Raman spectroscopy showed the presence of zirconia-anchored mono-oxotungstate as the major tungsten species present in this catalyst. These catalysts were used in benzoylation of veratrole with benzoic anhydride and 15 SZ-750 catalyst showed the highest activity. For catalyst with support calcined at different temperatures before HPA impregnation, catalytic activity decreases as the support calcination temperature increases due to the decrease in Bronsted acidity. Comparison of the catalytic activity of 15 SZ-750 with that of zirconia-supported phosphotungstic acid (15%, calcined at 750 degrees C, 15 PZ-750) in benzoylation of veratrole with benzoic anhydride, acylation of anisole with acetic anhydride and in alkylation of diphenylether with 1-dodecene showed that 15 SZ-750 catalyst has higher activity and deactivation resistance due to its higher Bronsted acidity. The deactivated catalyst could be regenerated by calcination without appreciable loss in activity. (c) 2006 Elsevier B.V. All rights reserved.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">1-2</style></issue><work-type><style face="normal" font="default" size="100%">Article</style></work-type><custom3><style face="normal" font="default" size="100%">&lt;p&gt;Foreign&lt;/p&gt;</style></custom3><custom4><style face="normal" font="default" size="100%">3.958</style></custom4></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Justus, Josena</style></author><author><style face="normal" font="default" size="100%">Vinu, Ajayan</style></author><author><style face="normal" font="default" size="100%">Devassy, Biju M.</style></author><author><style face="normal" font="default" size="100%">Balasubramanian, Veerappan V.</style></author><author><style face="normal" font="default" size="100%">Bohringer, Walter</style></author><author><style face="normal" font="default" size="100%">Fletcher, Jack C. Q.</style></author><author><style face="normal" font="default" size="100%">Halligudi, Shivaraj B.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Highly efficient and chemo selective catalyst system for the synthesis of blossom orange fragrance and flavoring compounds</style></title><secondary-title><style face="normal" font="default" size="100%">Catalysis Communications</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Acetal</style></keyword><keyword><style  face="normal" font="default" size="100%">acylal</style></keyword><keyword><style  face="normal" font="default" size="100%">Silicotungstic acid</style></keyword><keyword><style  face="normal" font="default" size="100%">tungsten oxide</style></keyword><keyword><style  face="normal" font="default" size="100%">tungstophosphoric acid</style></keyword><keyword><style  face="normal" font="default" size="100%">Zirconia</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">APR</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">7</style></number><publisher><style face="normal" font="default" size="100%">ELSEVIER SCIENCE BV</style></publisher><pub-location><style face="normal" font="default" size="100%">PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS</style></pub-location><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">1671-1675</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;{Acetal and acylal formation reactions of organic compounds are efficiently catalyzed by zirconia-supported mixed oxide systems under liquid-phase reaction conditions. 15WZ-750 (where&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><work-type><style face="normal" font="default" size="100%">Article</style></work-type><custom3><style face="normal" font="default" size="100%">Foreign</style></custom3><custom4><style face="normal" font="default" size="100%">3.389</style></custom4></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Sunita, G.</style></author><author><style face="normal" font="default" size="100%">Devassy, Biju M.</style></author><author><style face="normal" font="default" size="100%">Vinu, Ajayan</style></author><author><style face="normal" font="default" size="100%">Sawant, Dhanashri P.</style></author><author><style face="normal" font="default" size="100%">Balasubramanian, Veerappan V.</style></author><author><style face="normal" font="default" size="100%">Halligudi, Shivappa B.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Synthesis of biodiesel over zirconia-supported isopoly and heteropoly tungstate catalysts</style></title><secondary-title><style face="normal" font="default" size="100%">Catalysis Communications</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Biodiesel</style></keyword><keyword><style  face="normal" font="default" size="100%">phosphotungstic acids</style></keyword><keyword><style  face="normal" font="default" size="100%">Silicotungstic acid</style></keyword><keyword><style  face="normal" font="default" size="100%">transesterification</style></keyword><keyword><style  face="normal" font="default" size="100%">tungsten oxide</style></keyword><keyword><style  face="normal" font="default" size="100%">Zirconia</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">MAR</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">5</style></number><publisher><style face="normal" font="default" size="100%">ELSEVIER SCIENCE BV</style></publisher><pub-location><style face="normal" font="default" size="100%">PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS</style></pub-location><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">696-702</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;The liquid-phase synthesis of biodiesel by transesterification of sunflower oil with methanol is carried out by using zirconia-supported isopoly and heteropoly tungstates (HPAs) as catalysts. The isopoly and heteropoly tungstate catalysts were prepared by suspending zirconium oxyhydroxide in water/methanol solution of ammonium metatungstate/silicotungstic acid, phosphotungstic acid (WO3/HPA loading, 15%,,) followed by drying and calcination at 750 degrees C. The catalysts were characterized by XRD, Raman spectroscopy, IR spectroscopy, NH3-TPD and FTIR pyridine adsorption spectroscopy. XRD results indicate that the presence of isopoly and heteropoly tungstates stabilizes ZrO2 in tetragonal phase. Raman and IR spectra of the catalysts show that tungstate species exist as zirconia-anchored octahedral mono-oxotungstate. The acidity measurements by NH3-TPD and FTIR pyridine adsorption spectroscopy show that zirconia-supported phosphotungstate has the highest total acidity and zirconia-supported isopoly tungstate has the highest Bronsted acidity. The zirconia-supported isopoly tungstate shows superior catalytic performance compared to zirconia-supported heteropoly tungstate catalysts. Under the reaction conditions of 200 degrees C and methanol/oil molar ratio 15, 15% WO3/ZrO2 calcined at 750 degrees C gave 97% conversion of oil. This catalyst also efficiently catalyzes methanolysis of other vegetable oils like mustard oil and sesame oil. The deactivated catalyst could be regenerated by calcination without appreciable loss in activity. (c) 2007 Elsevier B.V. All rights reserved.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><work-type><style face="normal" font="default" size="100%">Article</style></work-type><custom3><style face="normal" font="default" size="100%">Foreign</style></custom3><custom4><style face="normal" font="default" size="100%">3.389</style></custom4></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Waghmare, Nilesh G.</style></author><author><style face="normal" font="default" size="100%">Kasinathan, Palraj</style></author><author><style face="normal" font="default" size="100%">Amrute, Amol P.</style></author><author><style face="normal" font="default" size="100%">Lucas, Nishita</style></author><author><style face="normal" font="default" size="100%">Halligudi, Shivaraj B.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Titania supported silicotungstic acid: an efficient solid acid catalyst for veratrole acylation</style></title><secondary-title><style face="normal" font="default" size="100%">Catalysis Communications</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">acetic anhydride</style></keyword><keyword><style  face="normal" font="default" size="100%">Acylation</style></keyword><keyword><style  face="normal" font="default" size="100%">Silicotungstic acid</style></keyword><keyword><style  face="normal" font="default" size="100%">titania</style></keyword><keyword><style  face="normal" font="default" size="100%">veratrole</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">JUN</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">10</style></number><publisher><style face="normal" font="default" size="100%">ELSEVIER SCIENCE BV</style></publisher><pub-location><style face="normal" font="default" size="100%">PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS</style></pub-location><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">2026-2029</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Titania supported silicotungstic acid (STA) with different STA loading (10-25 wt%) and calcination temperature (650-750 degrees C) were prepared by wet impregnation method. The catalysts have been represented by a general formula xSTiO(2)y (where x denotes wt%, S denotes STA and y denotes calcination temperature in degrees C). These catalysts were characterized by techniques such as X-ray diffraction, surface analysis, FTIR-pyridine and TPD-NH(3) and were used as heterogeneous solid acid catalysts in the liquid phase acylation of veratrole with acetic anhydride (Ac(2)O). It was found that 20STiO(2)700 gave the highest activity in acylation reaction due to its highest acidity. (C) 2008 Elsevier B.V. All rights reserved.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><work-type><style face="normal" font="default" size="100%">Article</style></work-type><custom3><style face="normal" font="default" size="100%">Foreign</style></custom3><custom4><style face="normal" font="default" size="100%">3.389</style></custom4></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Selvakumar, S.</style></author><author><style face="normal" font="default" size="100%">Singh, A. P.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Benzoylation of anisole over silicotungstic acid modified mesoporous alumina</style></title><secondary-title><style face="normal" font="default" size="100%">Catalysis Letters</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Friedel-Craft acylation</style></keyword><keyword><style  face="normal" font="default" size="100%">Mesoporous alumina</style></keyword><keyword><style  face="normal" font="default" size="100%">Silicotungstic acid</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">MAR</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">3-4</style></number><publisher><style face="normal" font="default" size="100%">SPRINGER</style></publisher><pub-location><style face="normal" font="default" size="100%">233 SPRING ST, NEW YORK, NY 10013 USA</style></pub-location><volume><style face="normal" font="default" size="100%">128</style></volume><pages><style face="normal" font="default" size="100%">363-372</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Mesoporous alumina (MA) molecular sieves were synthesized by using aluminum sec-butoxide as Al precursor and lauric acid as the structure directing agent. The synthesized MA was functionalized with silicotungstic acid (STA) via wet impregnation method and characterized by various physico-chemical techniques. The XRD patterns of a series of HPA functionalized MA are showing the ordered structures. N(2) sorption analysis shows type IV isotherm. NH(3)-TPD measurements revealed an increase in number of acid sites with an increase in loading of STA over MA. At the same time decrease in the acidity was observed with the increase in calcination temperature of the supported materials. Functionalization of STA were also carried out over different alumina supports such as catapol-B (CB) and alumina synthesized without surfactant (ASW) and their activities were evaluated by carrying out liquid phase Friedel-Craft acylation (FC) reaction of anisole with p-toluoyl chloride in a batch reactor at 120 degrees C. Recycling was performed in the FC reaction using 30 wt% STA-MA two times and no major deactivation of the catalyst was observed.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">3-4</style></issue><custom3><style face="normal" font="default" size="100%">Foreign</style></custom3><custom4><style face="normal" font="default" size="100%">1.907</style></custom4></record></records></xml>