02769nas a2200301   4500008004100000022001400041245007700055210006900132260007300201300001200274490000800286520177700294653001802071653001302089653001302102653002402115653001502139100002802154700002402182700002402206700001902230700001902249700002302268700002402291700002402315700001802339856011002357       2009                        eng d  a1381-116900aAcetalization of glycerol using mesoporous MoO3/SiO2 solid acid catalyst0 aAcetalization of glycerol using mesoporous MoO3SiO2 solid acid c  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcSEP  a150-1580 v3103 a<p>Acetalization of glycerol with various aldehydes has been carried out using mesoporous MoO3/SiO2 as a solid acid catalyst. A series of MoO3/SiO2 catalysts with varying MoO3 loadings(1-20 mol%) were prepared by sol-gel technique using ethyl silicate-40 and ammonium heptamolybdate as silica and molybdenum source respectively. The sol-gel derived samples were calcined at 500 degrees C and characterized using various physicochemical characterization techniques. The XRD of the calcined samples showed the formation of amorphous phase up to 10 mol% MoO3 loading and at higher loading of crystalline alpha-MoO3 on amorphous silica support. TEM analyses of the materials showed the uniform distribution of MoO3 nanoparticles on amorphous silica support. Raman spectroscopy showed the formation of silicomolybdic acid at low Mo loading and a mixture of alpha-MoO3 and polymolybdate species at high Mo loadings. Moreover the Raman spectra of intermediate loading samples also suggest the presence of beta-MoO3. Acetalization of glycerol with benzaldehyde was carried out using series of MoO3/SiO2 catalysts with varying MoO3 loadings (1-20 mol%). Among the series, MoO3/SiO2 With 20 mol% MoO3 loadings was found to be the most active catalyst in acetalization under mild conditions. Maximum conversion of benzaldehyde (72%) was obtained in 8 h at 100 degrees C with 60% selectivity for the six-membered acetal using 20% MoO3/SiO2. Interestingly with substituted benzaldehydes under same reaction conditions the conversion of aldehydes decreased with increase in selectivity for six-membered acetals. These results indicate the potential of this catalyst for the acetalization of glycerol for an environmentally benign process. (C) 2009 Elsevier B.V. All rights reserved.</p>10aAcetalization10aAldehyde10aGlycerol10aSilicomolybdic acid10asolid acid1 aUmbarkar, Shubhangi, B.1 aKotbagi, Trupti, V.1 aBiradar, Ankush, V.1 aPasricha, Renu1 aChanale, Jyoti1 aDongare, Mohan, K.1 aMamede, Anne-Sophie1 aLancelot, Christine1 aPayen, Edmond  uhttps://library.ncl.res.in/content/acetalization-glycerol-using-mesoporous-moo3sio2-solid-acid-catalyst-001886nas a2200277   4500008004100000022001400041245014000055210006900195260007300264300001200337490000700349520085800356653002101214653001601235653002901251653001801280653003401298100001901332700002801351700002301379700002401402700002101426700002501447700001601472856012001488       2012                        eng d  a1566-736700aDeposition-precipitation versus anionic-exchange Au/Al2O3 catalysts: a comparative investigation towards the selective reduction of NOx0 aDepositionprecipitation versus anionicexchange AuAl2O3 catalysts  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcSEP  a225-2300 v263 a<p>Catalytic properties of supported gold catalysts on gamma-Al2O3 prepared by a conventional deposition-precipitation method were compared with those obtained by anionic-exchange for the reduction of NOx by hydrocarbon under lean conditions that simulate Diesel engine exhaust gas. Interestingly, a catalytic activity enhancement is observed after thermal ageing under reactive conditions at 500 degrees C on anionic-exchanged samples which make them suitable for practical developments. On the other hand, the reverse trend is observed on the solids prepared by deposition-precipitation which deactivate at low temperature. Such changes in catalytic properties have been tentatively explained on the basis of textural and structural modifications taking place during thermal ageing under wet atmosphere. (C) 2012 Elsevier B.V. All rights reserved.</p>10aAnionic-exchange10aAu catalyst10aDeposition-precipitation10aNOx abatement10aSelective catalytic reduction1 aNguyen, D., L.1 aUmbarkar, Shubhangi, B.1 aDongare, Mohan, K.1 aLancelot, Christine1 aGirardon, J., S.1 aDujardin, Christophe1 aGranger, P.  uhttps://library.ncl.res.in/content/deposition-precipitation-versus-anionic-exchange-aual2o3-catalysts-comparative-002150nas a2200337   4500008004100000022001400041245009600055210006900151260007700220300001400297490000600311520104700317653001101364653002801375653001501403653002001418653001301438100001901451700001501470700001801485700001801503700002101521700001601542700002001558700002301578700002801601700001601629700001401645700002401659856012901683       2012                        eng d  a1867-388000aOne-pot sol-gel preparation for efficient cobalt-molybdenum-titania hydrotreating catalysts0 aOnepot solgel preparation for efficient cobaltmolybdenumtitania   aBOSCHSTRASSE 12, D-69469 WEINHEIM, GERMANYbWILEY-V C H VERLAG GMBHcDEC  a2112-21200 v43 a<p>Titania-based hydrodesulfurization catalysts were prepared by using a one-pot solgel method with the titanium peroxo complex as titanium precursor and molybdenum and cobalt precursors dissolved in the aqueous hydrogen peroxide solution used during synthesis. Catalysts with MoO3 loadings varying from 5 to 40 wt?% and a Co/Mo atomic ratio of 0.5 were prepared. Solids with molybdenum loadings below 20 wt?% MoO3 demonstrated poor hydrodesulfurization activity for the model compound thiophene. This was attributed to the presence of a large amount of embedded cobalt and molybdenum species in the titania matrix. A significant increase in the catalytic activity was observed for solids containing 20 and 25 wt?% of MoO3 on which active species appeared to be accessible on the titania surface. Furthermore, the highest conversion obtained on these solgel solids was superior to the highest conversion obtained on reference catalysts prepared through the impregnation of ammonium heptamolybdate and cobalt nitrate on commercial titania.</p>10acobalt10aheterogeneous catalysis10aMolybdenum10asol-gel process10atitanium1 aNguyen, D., L.1 aGillot, S.1 aSouza, D., O.1 aBlanchard, P.1 aLamonier, Carole1 aBerrier, E.1 aKotbagi, T., V.1 aDongare, Mohan, K.1 aUmbarkar, Shubhangi, B.1 aCristol, S.1 aPayen, E.1 aLancelot, Christine  uhttps://library.ncl.res.in/content/one-pot-sol-gel-preparation-efficient-cobalt-molybdenum-titania-hydrotreating-catalysts-001686nas a2200325   4500008004100000022001400041245008800055210006900143260007700212300001400289490000600303520057400309653002800883653001600911653001400927653002200941653002400963100002000987700002201007700002401029700002101053700003101074700001501105700002001120700003101140700002801171700002301199700002201222856011601244       2012                        eng d  a1864-563100aTransesterification of diethyl oxalate with phenol over sol-gel MoO3/TiO2 catalysts0 aTransesterification of diethyl oxalate with phenol over solgel M  aBOSCHSTRASSE 12, D-69469 WEINHEIM, GERMANYbWILEY-V C H VERLAG GMBHcJUL  a1467-14730 v53 a<p>The transesterification of diethyl oxalate (DEO) with phenol to form diphenyl oxalate (DPO) has been carried out in the liquid phase over very efficient MoO3/TiO2 solid-acid solgel catalysts. A selectivity of 100?% with a remarkable maximum yield of 88?% were obtained, which opens the route to downstream phosgene-free processes for the synthesis of polycarbonates. Interpretation of the results of various acidity measurements (NH3 and pyridine desorption, methanol oxidation as a probe reaction) allowed us to identify the catalytic sites as Lewis acid sites.</p>10aheterogeneous catalysis10aLewis acids10aOxidation10asol-gel processes10atransesterification1 aKotbagi, Trupti1 aNguyen, Duy, Luan1 aLancelot, Christine1 aLamonier, Carole1 aThavornprasert, Kaew-Arpha1 aWenli, Zhu1 aCapron, Mickael1 aJalowiecki-Duhamel, Louise1 aUmbarkar, Shubhangi, B.1 aDongare, Mohan, K.1 aDumeignil, Franck  uhttps://library.ncl.res.in/content/transesterification-diethyl-oxalate-phenol-over-sol-gel-moo3tio2-catalysts-001810nas a2200277   4500008004100000022001400041245013400055210006900189260007500258300001200333490000700345520077700352653002101129653002201150653002901172653001801201653003401219100002001253700002801273700002301301700002401324700002101348700002501369700001601394856012201410       2013                        eng d  a1022-552800aPromising stability of gold-based catalysts prepared by direct anionic exchange for DeNO (x) applications in lean burn conditions0 aPromising stability of goldbased catalysts prepared by direct an  a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGER/PLENUM PUBLISHERScMAY  a157-1640 v563 a<p>Supported gold catalysts on gamma-Al2O3 have been investigated in the catalytic reduction of NO (x) in simulated Diesel exhaust gas conditions. Different parameters have been examined essentially the mode of gold incorporation via classical deposition-precipitation and anionic exchange methods and the nature of the pre-activation thermal treatment. The resistance to thermal ageing under reactive conditions at 500 A degrees C was found completely different with a significant rate enhancement on anionic-exchange samples. Further comparisons also show that the nature of the pre-activation thermal treatment influences the extent of surface reconstructions during thermal ageing with a detrimental effect of reductive pre-treatment on the catalytic performances.</p>10aAnionic-exchange10aAu/Al2O3 catalyst10aDeposition-precipitation10aNOx abatement10aSelective catalytic reduction1 aNguyen, D., -L.1 aUmbarkar, Shubhangi, B.1 aDongare, Mohan, K.1 aLancelot, Christine1 aGirardon, J., S.1 aDujardin, Christophe1 aGranger, P.  uhttps://library.ncl.res.in/content/promising-stability-gold-based-catalysts-prepared-direct-anionic-exchange-deno-x-001941nas a2200301   4500008004100000022001400041245014000055210006900195260007300264300001000337490000800347520087400355653002001229653002101249653002101270653001101291100002001302700001901322700002301341700002801364700001301392700002101405700002501426700002401451700002401475700001601499856012401515       2015                        eng d  a0926-337300aRational preparation of Ag and Au bimetallic catalysts for the hydrocarbon-SCR of NOx: sequential deposition vs. coprecipitation method0 aRational preparation of Ag and Au bimetallic catalysts for the h  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcJAN  a11-200 v1623 a<p>This study emphasizes the importance of the preparation method for bimetallic Au-Ag catalysts supported on alumina in the selective reduction of NOx by hydrocarbons with gas feed compositions representative of diesel fuelled engine exhaust gas. An optimal balance between oxidative and reductive surface properties is obtained when Au and Ag are successively introduced. Significant re-dispersion processes take place when the catalyst runs at 500 degrees C leading to a gain in activity at low temperature and ascribed to a better interaction between Au and Ag species. Co-precipitation leads to a preferential formation of intermetallic Au-Ag particles which is detrimental to the catalytic performances. Aging at 500 degrees C leads to a significant particle sintering and a strengthening of the metallic character. (C) 2014 Elsevier B.V. All rights reserved.</p>10aAu-Ag particles10aCo-precipitation10aDeNO(x) reaction10aHC-SCR1 aMore, Pavan, M.1 aNguyen, D., L.1 aDongare, Mohan, K.1 aUmbarkar, Shubhangi, B.1 aNuns, N.1 aGirardon, J., S.1 aDujardin, Christophe1 aLancelot, Christine1 aMamede, Anne-Sophie1 aGranger, P.  uhttps://library.ncl.res.in/content/rational-preparation-ag-and-au-bimetallic-catalysts-hydrocarbon-scr-nox-sequential-0