%0 Journal Article
%T CeO2掺杂的Mn/Al催化剂的物化、表面及催化性能
%A Nasr Allah M. DERAZ
%J 催化学报
%P 687-695
%D 2008
%X ？PureandCeO2-dopedMn/Almixedoxideswerepreparedbythewetimpregnationmethodusingfinelypowderedalumina,manganese,andceriumnitrates.Thephysicochemical,surface,andcatalyticpropertiesofthethermallytreatedsolids(at500,800,and900℃)wereinvestigatedusingXRD,nitrogenadsorptionat-196℃,andhydrogenperoxidedecompositioninanaqueoussolutionat30~50℃.TheMnoxidationstatechangedfromMn4+toMn2+onincreasingthecalcinationtemperature.ThereweretwouniquefeaturesassociatedwithCeO2thatareofinterest.Thefirstwasthatitfavoredthedispersionofmanganeseoxidesdepositedontheγ-Al2O3catalystcalcinedat500℃.ThesecondwasthatitenhancedtheformationofMn3O4speciesfromMn2O3depositedinitiallyonthealuminasupportcalcinedat800and900℃.Consequently,thespecificsurfaceareaoftheMn/Almixedoxidescalcinedat500℃wasincreasedbyincreasingtheamountofdopantadded.Anoppositeeffectwasobservedbyincreasingthecalcinationtemperaturefrom500to900℃.Thedopingfollowedbycalcinationatdifferenttemperaturesbroughtaboutanincreaseinthecatalyticactivityofmixedoxides.Pretreatmentsdidnotmodifythemechanismofthecatalyzedreactionbutchangedthenumberofcatalyticallyactivesiteswithoutchangingthenatureofthesesites.
%K catalyticactivity
%K manganeseoxide
%K activationenergy
%K alumina
%U http://www.chxb.cn/CN/abstract/abstract16982.shtml