Ni-MZrO2双金属催化剂制备及其催化5-羟甲基糠醛选择性加氢脱氧性能研究

]。3.35-羟甲基糠醛催化加氢反应条件研究Ni-M/ZrO2双金属催化剂在催化HMF加氢制备2,5-DMF反应中性能会受到催化加氢反应条件影响，所以进一步探究反应温度、反应压力和反应时间条件不同时产生的不同影响，同时还考察了催化剂重复利用性。通过对反应产物进行气相色谱分析，计算HMF的转化率与2,5-DMF的收率，以此全面评估不同反应条件对产物分布的影响。3.3.1反应温度的影响实验中选用Ni-Mo/ZrO2为催化剂，着重探究不同反应温度(120℃、140℃、160℃、180℃、200℃)对Ni-Mo/ZrO2催化HMF加氢制备2,5-DMF反应性能的具体影响。结果如图3-4所示。由图3-4中可知，2,5-DMF收率随反应温度的升高，呈现出先增大后减小的趋势。随着反应温度从120℃升高到200℃，转化率呈现持续上升趋势，到160℃时接近100%。这表明温度升高能有效促进反应进行，使更多反应物转化为产物。当反应温度为120℃时，HMF的转化率和2,5-DMF收率分别为62.5%和36.4%；然而在温度为160℃下，该催化剂可使得HMF加氢脱氧生成2,5-DMF的收率显著提高，达到80.1%。当180℃时，2,5-DMF收率达最大值85.3%。温度进一升高时，HMF催化加氢制备2,5-DMF的收率表现出下降，收率下降至80.7%。这是因为反应温度过高，可能因过度加氢，副反应程度加剧。故选取反应温度为180℃为最佳反应温度。图3-4不同反应温度下的Ni-Mo/ZrO2催化HMF加氢反应反应条件：1gHMF,0.2gcatalyst,30mLisopropanol,180℃,6h,3MPaH23.3.2反应压力的影响实验中保持其他条件固定，针对不同反应压力(1.5MPa、2MPa、2.5MPa、3MPa、3.5MPa)对Ni-Mo/ZrO2催化HMF加氢制备2,5-DMF反应性能的具体影响。结果如图3-5所示。由图3-5，可知在氢气压力考察范围内，随着H2​压力从1.5MPa逐渐增加到3MPa

，HMF转化率呈现明显的上升趋势，从初始的较低水平逐步攀升至接近100%

。在3MPa之后，转化率维持在高位，基本稳定。这表明增加H2压力有利于反应进行，促进反应物转化为产物。当氢气压力为1.5MPa时，HMF的转化率和2,5-DMF收率分别为68.4%和45.3%；当压力逐渐增大，该催化剂可使HMF加氢生成2,5-DMF的收率显著提高。当氢气压力增加至3MPa时，2,5-DMF收率达最大值84.0%。继续升高氢气压力3.5MPa时，2,5-DMF的收率开始下降至81.0%。在考察的压力范围内，从2.5MPa开始HMF的转化率都在95%以上，并且在3MPa之后，转化率保持在100%。因而升高压力确实能促进加氢反应的进行。但是氢气压力过高会导致过度加氢，生成四氢呋喃类副产物。因此选取3MPa为该反应的最佳氢气压力。图3-5不同反应压力下的Ni-Mo/ZrO2催化HMF加氢反应反应条件：1gHMF,0.2gcatalyst,30mLisopropanol,180℃,6h,3MPaH23.3.3反应时间的影响实验中保持其他条件固定，针对不同反应时间(2h、4h、6h、8h、10h)对Ni-Mo/ZrO2催化HMF加氢制备2,5-DMF反应性能的具体影响。结果如图3-6所示。由图3-6可知，随着反应时间从2h到10h，转化率逐渐上升，从2h时的约75%左右逐步升高，到6h左右达到100%，之后基本保持稳定。这表明延长反应时间能促进反应进行，使更多反应物转化为产物，且反应在6h左右基本达到平衡状态。当反应时间为2h时，2,5-DMF占比为49.3%，是主要产物之一。随着反应时间延长，其占比不断增加，4h时达到71.6%，6h时升至82.3%，从8h开始下降，但10h仍保持在79.5%的较高水平。说明适当延长反应时间有利于生成2,5-DMF，可能是因为反应需要一定时间来积累中间产物并逐步转化为2,5-DMF。然而，当反应时间超出适宜范围，过长的反应时长可能会促使2,5-DMF进一步发生转化，生成其他副产物。所以需要综合考量反应时间对HMF转化率及2,5-DMF收率这两个重要指标的影响。选取6h为该反应的最佳反应时间。图3-6不同反应时间下的Ni-Mo/ZrO2催化HMF加氢反应反应条件：1gHMF,0.2gcatalyst,30mLisopropanol,180℃,6h,3MPaH23.3.4催化剂重复性利用实验中保持其他条件固定，考察催化剂循环次数(1、2、3、4、5)对Ni-Mo/ZrO2催化HMF加氢制备2,5-DMF反应性能的具体影响。结果如图3-7所示。图3-7表示Ni-Mo/ZrO2催化剂重复利用情况。总体来看，随着循环次数增加，2,5-DMF产率呈现逐渐下降趋势，首次循环时，2,5-DMF的产率达到了83.3%，表明Ni-Mo/ZrO2催化剂在初次使用时具有较高活性，能够有效地促进反应的进行，多次循环使用过程产率逐渐下降，但经过回收处理后，产率有明显回升。反映了催化剂在多次循环使用过程中活性逐渐降低，但通过一定的回收处理，能使其部分恢复活性，从而提高2,5-DMF的产率。图3-7Ni-Mo/ZrO2催化剂在HMF催化2.5-DMF反应中的重复利用反应条件：1gHMF,0.2gcatalyst,30mLisopropanol,180℃,6h,3MPaH2第四章结论与展望4.1结论本文围绕生物质资源，通过浸渍法制备了以ZrO2为载体负载Ni、Mo双金属的催化剂。利用此催化剂对HMF加氢制备2,5-DMF的反应进行探究。并探究了Ni-Mo/ZrO2催化剂的结构表征，根据在不同反应温度、反应压力、反应时间条件下的HMF转化率与2,5-DMF收率，最终获得了反应的优选条件。综合研究内容，可得到以下结论：运用XRD、SEM、FT-IR表征对Ni-Mo/ZrO2催化剂进行深入分析，结果表明ZrO2载体与所负载的Ni、Mo金属之间结合良好，颗粒大小分散均匀，有利于反应物与催化剂充分接触，进而促进催化反应。采用ZrO2负载Ni、Mo组分制备Ni-Mo/ZrO2催化剂，用量固定为催化剂0.2g，HMF1g，IPA30mL，在反应压力为3MPa，反应时间6h，反应温度180℃时催化效率最佳。在H2氛围下HMF加氢转化率为100%，2.5-DMF的收率在83.3%。4.2展望尽管本文在Ni-M/ZrO2双金属催化剂用于5-HMF加氢脱氧制备2,5-DMF方面取得了一定成果，但仍有诸多方面值得进一步深入探索和研究：虽然对Ni-Mo/ZrO2催化剂的性能有了一定了解，但催化机理未完全明晰。利用更先进的表征技术(如原位表征技术)和理论计算方法，深入研究催化剂在反应过程中的活性位点变化、反应中间体的形成与转化等，有助于从分子层面揭示催化反应的本质，为进一步优化催化剂设计提供更深入的理论指导。这将推动生物质催化转化领域的基础研究，促进新型高效催化剂的开发。参考文献GallezotP.Conversionofbiomasstoselectedchemicalproducts[J].ChemicalSocietyReview,2012,41:1538-1558.ShafaghatH,TsangY.F,JeonJ.K,etal.In-situhydrogenationofbio-oil/bio-oilphenoliccompoundswithsecondaryalcoholsoverasynthesizedmesoporousNi/CeO2catalyst[J].ChemicalEnglishJournal,2020,382:122912.KushwahaN,BanerjeeD,AhmadK.A,etal.Catalyticproductionandapplicationofbio-renewablebutylbutyrateasjetfuelblend-Areview[J].Environ.Manage,2022,310:114772.UllahK,SharmaV.K,AhmadM,etal.Theinsightviewsofadvancedtechnologiesanditsapplicationinbio-originfuelsynthesisfromlignocellulosebiomasseswaste[J].Renew.SustainEnergyReview,2018,82:3992-4008.JinM,SliningerP.J,DienB.S,etal.Microbiallipid-basedlignocellulosicbiorefinery:feasibilityandchallenges[J].TrendsinBiotechnology,2015,33:43-54.MalodeS.J,PrabhuK.K,MascarenhasR.J,etal.Recentadvancesandviabilityinbiofuelproduction[J].EnergyConversionandManagementX,2021,10:100070.LiuH,CaoX,WangT,etal.Efficientsynthesisofbio-monomer2,5-furandicarboxylicacidfromconcentrated5-hydroxymethylfurfuralorfructoseinDMSO/H2Omixedsolvent[J].JournalofIndustrialandEngineeringChemistry,2019,77(4):209-214.LiQ,WangH,TianZ,etal.Selectiveoxidationof5-hydroxymethylfurfuralto2,5-furandicarboxylicacidoverAu/CeO2,catalysts:themorphologyeffectofCeO2+[J].CatalysisScience&Technology,2019,9(7):1570-1580.KubotaS.R,ChoiK.Electrochemicaloxidationof5-hydroxymethylfurfuralto2,5-furandicarboxylicacid(FDCA)inacidicmediaenablingspontaneousFDCAseparation[J].ChemSusChem,2018,11(13):2138-2145.ShaoY,LiY,SunK,etal.Sulfatedzirconiawithdifferentcrystalphasesfortheproductionofethyllevulinateand5-hydroxymethylfurfural[J].EnergyTechnology,2019,48(2):1-10.TianY,DengJ,PanT,etal.Dehydrationofglucoseandfructoseinto5-hydroxymethylfurfuralcatalyzedbylewisacidinionicliquids[J].ChineseJournalofCatalysis,2011,32(6):997-1002.ShahangiF,ChermahiniA.N,SarajiM.Dehydrationoffructoseandglucoseto5-hydroxymethylfurfuraloverAl-KCC-1silica[J].JournalofEnergyChemistry,2018,27(3):769-780.RecheM.T,OsatiashtianiA,DurndellL.J,etal.Niobicacidnanoparticlecatalystsfortheaqueousphasetransformationofglucoseandfructoseto5-hydroxymethylfurfural[J].CatalysisScience&Technology,2016,6(19):7334-7341.RathodP.V,MujmuleR.B,ChungWJ,etal.Efficientdehydrationofglucose,sucroseandfructoseto5-hydroxymethylfurfuralusingtri-cationicionicliquids[J].CatalysisLetters,2019,149(3):672-687.PedersenA.T,RingborgR,GrotkjaerT,etal.Synthesisof5-hydroxymethylfurfural(HMF)byacidcatalyzeddehydrationofglucose-fructosemixtures[J].ChemicalEngineeringJournal,2015,273(14):455-464.NasirudeenM.B,HailesH.C,EvansJ.R.G.Preparationof5-hydroxymethylfurfuralfromglucoseandfructoseinionicliquidsbyreactivevacuumdistillationoverasolidcatalyst[J].CurrentOrganicSynthesis,2017,14(4):596-603.MimuraN,SatoO,ShiraiM,etal.5-Hydroxymethylfurfuralproductionfromglucose,fructose,cellulose,orcellulose-basedwastematerialbyusingacalciumphosphatecatalystandwaterasagreensolvent[J].Chemistryselect,2017,2(3):1305-1310.LiW,ZhangT,XinH,etal.p-Hydroxybenzenesulfonicacid-formaldehydesolidacidresinfortheconversionoffructoseandglucoseto5-hydroxymethylfurfural[J].RSCAdvances,2017,7(44):27682-27688.JezakS,DzidaM,ZorebskiM.Highpressurephysicochemicalpropertiesof2-methylfuranand2,5-dimethylfuran-secondgenerationbiofuels[J].Fuel,2016,184(4):334-343.ChenB,LiF,HuangZ,etal.Carbon-coatedCu-Cobimetallicnanoparticlesasselectiveandrecyclablecatalystsforproductionofbiofuel2,5-dimethylfuran[J].AppliedCatalysisB:Environmental,2017,200(2):192-199.YangP,XiaQ,LiuX,etal.Catalytictransferhydrogenation/hydrogenolysisof5-hydroxymethylfurfuralto2,5-dimethylfuranoverNi-Co/Ccatalyst[J].Fuel,2017,187(17):159-166.GawadeA.B,TiwariM.S,YadavG.D.Biobasedgreenprocess:BiobasedGreenProcess:SelectiveHydrogenationof5-Hydroxymethylfurfuralto2,5-DimethylFuranunderMildConditionsUsingPd-Cs2.5H0.5PW12O40/K-10Clay[J].ACSSustainableChemistry&Engineering,2016,4(8):4113-4123.ShiJ,WangY,YuX,etal.Productionof2,5-dimethylfuranfrom5-hydroxymethylfurfuraloverreducedgrapheneoxidessupportedPtcatalystundermildconditions[J].Fuel,2016,163(41):74-79.LiW,FanG,YangL,etal.Highlyefficientsynchronizedproductionofphenoland2,5-dimethylfuranthroughabimetallicNi-Cucatalyzeddehydrogenation-hydrogenationcouplingprocesswithoutanyexternalhydrogenandoxygensupply[J].GreenChemistry.2017,19(18):4353-4363.ZuY,YangP,WangJ,etal.Efficientproductionoftheliquidfuel2,5-dimethylfuranfrom5-hydroxymethylfurfuraloverRu/Co3O4catalyst[J].AppliedCatalysisB:Environmental,2014,146(18):244-248.JaeJ,ZhengW,LoboR.F,etal.Productionofdimethylfuranfromhydroxymethylfurfuralthroughcatalytictransferhydrogenationwithrutheniumsupportedoncarbon[J].ChemSusChem,2013,6(7):1158-1162.Roman-LeshkovY,BarrettC.J,LiuZ.Y,etal.Productionofdimethylfuranforliquidfuelsfrombiomass-derivedcarbohydrates[J].Nature,2007,447(7147):982-985.InsyaniR,VermaD,KimS.M,etal.Directone-potconversionofmonosaccharidesintohigh-yield2,5-dimethylfuranoveramultifunctionalPd/Zr-basedmetal–organicframework@sulfonatedgrapheneoxidecatalyst[J].GreenChemistry,2017,19(11):2482-2490.ChidambaramM,BellA.T,etal.Atwo-stepapproachforthecatalyticconversionofglucoseto2,5-dimethylfuraninionicliquids[J].GreenChemistry,2010,12(7):1253-1262.ChenN,ZhuZ,LüH,etal.Catalytichydrogenolysisofhydroxymethylfurfuraltohighlyselective2,5-dimethylfuranoverFeCoNi/h-BNcatalyst[J].ChemicalEngineeringJournal,2020,381:122755.HuL,TangX,XuJ,etal.Selectivetransformationof5-hydroxymethylfurfuralintotheliquidfuel2,5-dimethylfuranovercarbon-supportedruthenium[J].IndustrialandEngineeringChemistryResearch,2014,53(8):3056-3064.WangG,WangF,SchüthF,etal.Platinum-cobaltbimetallicnanoparticlesinhollowcarbonnanospheresforhydrogenolysisof5-hydroxymethylfurfural[J].NatureMaterials,2014,13(3):293-300.LouieY.L,TangJ,HellA.M.L,etal.Kineticsofhydrogenationandhydrogenolysisof2,5-dimethylfuranovernoblemetalscatalystsundermildconditions[J].AppliedCatalysisB:Environmental,2017,202:557-568.GoyalR,SarkarB,BordoloiA,etal.Studiesofsynergybetweenmetal-supportinterfacesandselectivehydrogenationofHMFtoDMFinwater[J].JournalofCatalysis,2016,340:248-260.GyngazovaM.S,NegahdarL,BlumenthalL.C,etal.Experimentalandkineticanalysisoftheliquidphasehydrodeoxygenationof5-hydroxymethylfurfuralto2,5-dimethylfuranovercarbon-supportednickelcatalysts[J].ChemicalEngineeringScience,2017,173:455-464.KongX,ZhuY,LiY,etal.Switchablesynthesisof2,5-dimethylfuranand2,5-dihydroxymethyltetrahydrofuranfrom5-hydroxymethylfurfuraloverRaneyNicatalyst[J].RSCAdvances,2014,4(105):60467-60472.KongX,ZhengR,ZhuY,etal.RationaldesignofNi-basedcatalystsderivedfromhydrotalciteforselectivehydrogenation5-hydroxymethylfurfural[J].GreenChemistry,2015,17(4):2504-2514.YangP,CuiQ,WangY,etal.Catalyticproductionof2,5-dimethylfuranfrom5-hydroxymethylfurfuraloverNi/Co3O4catalyst[J].CatalysisCommunications,2015,66:55-59.LiuX,WangD,LiY.Synthesisandcatalyticpropertiesofbimetallicnanomaterialswithvariousarchitectures[J].NanoToday,2012,7:448-66.YuW,PorosoffMarcD,ChenJ.ReviewofPt-basedbimetalliccatalysis:Frommodelsurfacestosupportedcatalysts[J].ChemicalReview,2012,112:5780-817.LiW,FanG,YangL,etal.Highlyefficientsynchronizedproductionofphenoland2,5-dimethylfuranthroughabimetallicNi-Cucatalyzeddehydrogenation-hydrogenationcouplingprocesswithoutanyexternalhydrogenandoxygensupply[J].GreenChemistry,2017,19(18):4353-4363.袁涛.5-羟甲基糠醛催化还原制备2,5-二甲基呋喃[D].河北工业大学,2014,07:1-56.AhmedH.A,AwadallahA.E,Aboul-EneinA.A,etal.Non-oxidativeDecompositionofCH4

OverCeO2

andCeO2–SiO2

SupportedBimetallicNi–MoCatalysts[J].CatalysisLetters,2022,152:2789-2800.ZhangY,FanG,YangL,etal.CooperativeEffectsbetweenNi-MoAlloySitesandDefectiveStructuresoverHierarchicalNi-MoBimetallicCatalystsEnabletheEnhancedHydrodeoxygenationActivity[J].ACSSustainableChemistry&Engineering,2021,9(34):11604-11615.YuY,DaiY,WangR,etal.MorphologyEffectofZrO2onTuningtheC–HBondActivationinPropaneDehydroge