02443nas a2200289   4500008004100000022001400041245012500055210006900180260007300249300001200322490000700334520143500341653001301776653002201789653001101811653003401822653002001856653000901876653002201885653000901907100001901916700002801935700001901963700002001982700002302002856012802025       2009                        eng d  a0926-337300aSupport modification to improve the sulphur tolerance of Ag/Al2O3 for SCR of NOx with propene under lean-burn conditions0 aSupport modification to improve the sulphur tolerance of AgAl2O3  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcAUG  a416-4250 v903 a<p>Ag/Al2O3 catalysts with 1 wt% SiO2 or TiO2 doping in alumina support have been prepared by wet impregnation method and tested for sulphur tolerance during the selective catalytic reduction (SCR) of NOx using propene under lean conditions, Ag/Al2O3 showed 44% NOx conversion at 623 K, which was drastically reduced to 21% when exposed to 20 ppm SO2. When Al2O3 support in Ag/Al2O3 Was doped with 1 wt% SiO2 or TiO2 the NOx conversion remained constant in presence of SO2 showing the improved sulphur tolerance of these catalysts. Subsequent water addition does not induce significant deactivation. On the contrary, a slight promotional effect on the activity of NO conversion to nitrogen is observed after Si and Ti incorporation. FTIR study showed the sulphation of silver and aluminum sites of Ag/Al2O3 catalysts resulting in the decrease in the formation of reactive intermediate species such as -NCO, which in turn decreases NOx conversion to N-2. In the case of Ag/Al2O3 doped with SiO2 or TiO2, formation of silver sulphate and aluminum sulphate was drastically reduced, which was evident in FTIR resulting in remarkable improvement in the sulphur tolerance of Ag/Al2O3 catalyst. These catalysts before and after the reaction have been characterized with various techniques (XRD, BET surface area, transmittance FTIR and pyridine adsorption) for physico-chemical properties. (C) 2009 Elsevier B.V. All rights reserved.</p>10aAg/Al2O310aAluminum sulphate10aDRIFTS10aSelective catalytic reduction10aSilver sulphate10aSiO210aSulphur tolerance10aTiO21 aJagtap, Neelam1 aUmbarkar, Shubhangi, B.1 aMiquel, Pierre1 aGranger, Pascal1 aDongare, Mohan, K.  uhttps://library.ncl.res.in/content/support-modification-improve-sulphur-tolerance-agal2o3-scr-nox-propene-under-lean-burn-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-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-0