<?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%">Kumbar, Suresh M.</style></author><author><style face="normal" font="default" size="100%">Shanbhag, G. V.</style></author><author><style face="normal" font="default" size="100%">Lefebvre, F.</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%">Heteropoly acid supported on titania as solid acid catalyst in alkylation of p-cresol with tert-butanol</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%">2</style></keyword><keyword><style  face="normal" font="default" size="100%">2-tert-butyl-p-cresol</style></keyword><keyword><style  face="normal" font="default" size="100%">6-di-tert-butyl-p-cresol</style></keyword><keyword><style  face="normal" font="default" size="100%">Alkylation</style></keyword><keyword><style  face="normal" font="default" size="100%">heteropoly acid</style></keyword><keyword><style  face="normal" font="default" size="100%">p-Cresol</style></keyword><keyword><style  face="normal" font="default" size="100%">tert-butanol</style></keyword><keyword><style  face="normal" font="default" size="100%">titania</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%">AUG</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%">256</style></volume><pages><style face="normal" font="default" size="100%">324-334</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Butylation of p-cresol with tert-butanol was investigated on titania modified with 12-tungstophosphoric acid (TPA/TiO2) catalyst under vapor phase conditions. Catalysts with different TPA loadings (10-25 wt.%) and calcination temperatures (650-750 degrees C) were prepared by suspending titanium hydroxide in methanol solution of TPA followed by drying and calcination. These catalysts were characterized by surface area, XRD, P-31 MAS NMR, XPS, NH3-TPD, and FTIR pyridine adsorption. XRD results indicated that the presence of TPA retarded the crystallization of titania and stabilized TiO2 in anatase phase. P-31 MAS NMR indicated the presence of TPA in various forms (dispersed, highly fragmented and Keggin intact). These catalysts showed both Bronsted and Lewis acidity, and 20% TPA on TiO2 calcined at 700 degrees C (from here after words 20% TT 700) had the highest Bronsted as well as total acidity. Further, the catalytic activities were examined in tert-butylation of p-cresol with tent-butanol. The catalytic activity depended on TPA coverage, and the highest activity corresponded to the monolayer of TPA on titania. The most active catalyst 20% TT-700 gave 82% conversion of p-cresol and 89.5% selectivity towards 2-tert-butyl cresol (TBC), 2,6-di-tert-butyl cresol (DTBC) 7.5% and cresol-tert-butyl ether (CTBE) 3% under optimized conditions. The activity was always higher than that of WO3/ZrO2, sulfated zirconia (SZ), USY, H-beta zeolites and montmorillonite K-10 (K-10mont) under similar conditions. (c) 2006 Elsevier B.V. All rights reserved.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">2-3</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></records></xml>