简介：Twokindsofgaseswereusedtoinvestigatetheinfluenceofgasdensityonthehydrodynamiccharacteristicsinabubblecolumn.Itcanbefoundoutthathighergasdensityleadstosmallerbubblediameterandtheflowpatternsaredifferentforthebothgases.Energybalancemechanismsareanalyzedbyconsideringthegasdensitydifference.Modelsweredevelopedtopredicttheaveragebubblediameterwithgoodaccuracy.

简介：Anexperimentalinstallationofcoldmodelsimulationwassetuptostudythebedpressuredropindifferentregionsoffixedfluidizedbedreactorduringtopfeedingandbottomfeeding,respectively,atvariousgasvelocitieswiththefluidizationimageofsolidparticlesmonitoredatthesametime.Bycomparingthechangesinbeddensityandoperatinggasvelocityindifferentregionsoffixedfluidizedbedreactor,theinfluenceoftopfeedingandbottomfeedingpatternsonfluidizationbehaviorcouldbeinvestigated.Theresultsshowedthatthebeddensityintopfeedingreactorrespondedmorestablytothechangeingasvelocityalongwiththeadvantageofworkinginawiderrangeofoperatinggasvelocities.Basedonthisstudy,itisconcludedthatexistingbottomfeedingreactorconfigurationscannotmeetthefluidizationrequirements;andoptimizationofbottomfeedingreactorwillbeneeded.

简介：Thispaperhasinvestigatedtheinfluenceofgasolinesulfurcontentondurabilityofcatalyticconverterforvehicleexhaustgas.Twogasolinesampleswithdifferentsulfurcontents(equatingto150μg/gand50μg/gofsulfur,respectively)wereusedtoexaminethedurabilityandperformanceofcatalyticconverteronthebenchtest.Thetestresultshaverevealedthatincomparisontotheinfluenceofsulfuronageingofcatalyticconverterthethermalageinghadamoreremarkableimpactontheperformanceofcatalyticconverter,andtheperformanceofcatalyticconvertercouldberestoredbyhigh-temperaturedesulfurizationprocessafterageingbythehigh-sulfurgasolinesample(containing150μg/gofsulfur).

简介：Inthisstudy,titaniumdioxidesupportedbymulti-walledcarbonnanotubes(MWCNTs/TiO2)andCr-dopedTiO2supportedbyMWCNTs(MWNTs/Cr-TiO2)weresynthesizedbythesol-gelmethod.Thepreparedsampleswerecharacterizedbytransmissionelectronmicroscopy,X-rayphotoelectronspectroscopy,X-raydiffraction,theBrunauerEmmett-Telleranalysis,andtheRamanspectroscopy.TheoxidationandefficiencyforremovalofSO2inasimulatedfluegaswereinvestigatedexperimentallyinafixed-bedreactor.The15%MWCNTs/Cr-Ti02sampledisplayedexcellentadsorptionproperties,andaSO2removalrateequatingto30.4151mg/gfromthesimulatedfluegascontaining2300μg/gofSO2,8%of02,and5%ofH20wasachievedunderoptimalconditionscoveringatemperatureof333.15K,andaspacevelocityof1275h^-1.TheadsorptionprocesswasenhancedbecauseCrdopingmodifiedtheporestructureandinhibitedthegraingrowthofTiO2.Inaddition,theFreundlichandLangmuirmodelsrevealedthatSO2wasmainlyadsorbedthroughchemicaladsorptiononthesamplesurfaces,andthethermodynamicmodelanalysisindicatedthattheadsorptionwasaspontaneous,exothermic,andentropy-reducingprocess.TheadsorptionkineticsofSO2canbedescribedbythepseudosecond-orderkineticandtheBanghamdynamicsmodels.Thepossiblereactionmechanisminvolvedindesulfurizationprocesswasalsoproposed.