Tuning of the textural features and acidic properties of sulfated mesoporous lanthana-zirconia solid acid catalysts for alkenylation of diverse aromatics to their corresponding α-arylstyrenes

Article abstract of DOI:10.1016/S1872-2067(15)61118-4

The textural features and acidic properties of sulfated mesoporous lanthana-zirconia solid acids (SO₄^2?/meso-La_0.1Zr_0.9O_δ) were efficiently tuned by modifying the conditions used to prepare the meso-La_0.1Zr_0.9O_δ composites, such as the molar ratio of the template to La and Zr metal ions (N_t/m), molar ratio of ammonia to La and Zr metal ions (N_a/m), hydrothermal temperature (T_hydro), and hydrothermal time (t_hydro). The effect of the textural features and acidic properties on the catalytic performance of solid acid catalysts for alkenylation of p-xylene with phenylacetylene was investigated. Various characterization techniques such as N₂ physisorption, X-ray diffraction, NH₃ temperature-programmed desorption, and thermogravimetric analysis were employed to reveal the relationship between the nature of catalyst and its catalytic performance. It was found that the catalytic performance significantly depended on the textural features and acidic properties, which were strongly affected by preparation conditions of the meso-La_0.1Zr_0.9O_δ composite. Appropriate acidic sites and high accessibility were required to obtain satisfactory catalytic reactions for this reaction. It was also found that the average crystallite size of t-ZrO₂ affected by the preparation conditions had significant influence on the ultrastrong acidic sites of the catalysts. The optimized SO₄^2?/meso-La_0.1Zr_0.9O_δ catalyst exhibited much superior catalytic activity and coke-resistant stability. Moreover, the developed SO₄^2?/meso-La_0.1Zr_0.9O_δ catalyst demonstrated excellent catalytic performance for alkenylation of diverse aromatics with phenylacetylene to their corresponding α-arylstyrenes. Combining the previously established complete regeneration of used catalysts by a facile calcination process with the improved catalytic properties, the developed SO₄^2?/meso-La_0.1Zr_0.9O_δ solid acid could be a potential catalyst for industrial production of α-arylstyrenes through clean and atom efficient solid-acid-mediated Friedel-Crafts alkenylation of diverse aromatics with phenylacetylene.

Full text of DOI:10.1016/S1872-2067(15)61118-4

ChineseꢀJournalꢀofꢀCatalysisꢀ37ꢀ(2016)ꢀ1303–1313
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ꢀ ꢀ ꢀ
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a v a i l a b l e a t w w w . s c i e n c e d i r e c t . c o m
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j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / c h n j c
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Article
Tuningꢀofꢀtheꢀtexturalꢀfeaturesꢀandꢀacidicꢀpropertiesꢀofꢀsulfatedꢀ
mesoporousꢀlanthana‐zirconiaꢀsolidꢀacidꢀcatalystsꢀforꢀalkenylationꢀ
ofꢀdiverseꢀaromaticsꢀtoꢀtheirꢀcorrespondingꢀα‐arylstyrenesꢀ
ꢀ
ZhongkuiꢀZhao*,ꢀJinfengꢀRan,ꢀYongleꢀGuo,ꢀBoyuanꢀMiao,ꢀGuiruꢀWang
ꢀ
StateꢀKeyꢀLaboratoryꢀofꢀFineꢀChemicals,ꢀDepartmentꢀofꢀCatalysisꢀChemistryꢀandꢀEngineering,ꢀSchoolꢀofꢀChemicalꢀEngineering,ꢀDalianꢀUniversityꢀofꢀ ꢀ
Technology,ꢀDalianꢀ116024,ꢀLiaoning,ꢀChinaꢀ
A R T I C L E ꢀ I N F O ꢀ
A B S T R A C T ꢀ
Articleꢀhistory:ꢀ
Theꢀ texturalꢀ featuresꢀ andꢀ acidicꢀ propertiesꢀ ofꢀ sulfatedꢀ mesoporousꢀ lanthana‐zirconiaꢀ solidꢀ acids
Receivedꢀ17ꢀMarchꢀ2016ꢀ
Acceptedꢀ20ꢀAprilꢀ2016ꢀ
Publishedꢀ5ꢀAugustꢀ2016ꢀ
(SO 2
4
−/meso‐La0.1Zr0.9
δ
O )ꢀ wereꢀ efficientlyꢀ tunedꢀ byꢀ modifyingꢀ theꢀ conditionsꢀ usedꢀ toꢀ prepareꢀ theꢀ
δ
meso‐La0.1Zr0.9O ꢀcomposites,ꢀsuchꢀasꢀtheꢀmolarꢀratioꢀofꢀtheꢀtemplateꢀtoꢀLaꢀandꢀZrꢀmetalꢀionsꢀ(Nt/m),ꢀ
molarꢀratioꢀofꢀammoniaꢀtoꢀLaꢀandꢀZrꢀmetalꢀionsꢀ(Na/m),ꢀhydrothermalꢀtemperatureꢀ(Thydro),ꢀandꢀhy‐
drothermalꢀ timeꢀ (thydro).ꢀTheꢀeffectꢀofꢀtheꢀtexturalꢀfeaturesꢀandꢀacidicꢀpropertiesꢀonꢀtheꢀcatalyticꢀ
performanceꢀofꢀsolidꢀacidꢀcatalystsꢀforꢀalkenylationꢀofꢀp‐xyleneꢀwithꢀphenylacetyleneꢀwasꢀinvesti‐
Keywords:ꢀ
Mesoporousꢀsolidꢀacidꢀ
Alkenylationꢀ
Cleanꢀsynthesisꢀ
Alkenylꢀaromaticsꢀ
Texturalꢀandꢀacidicꢀpropertiesꢀ
Tuningꢀ
gated.ꢀVariousꢀcharacterizationꢀtechniquesꢀsuchꢀasꢀN
2
ꢀphysisorption,ꢀX‐rayꢀdiffraction,ꢀNH ꢀtemper‐
3
ature‐programmedꢀdesorption,ꢀandꢀthermogravimetricꢀanalysisꢀwereꢀemployedꢀtoꢀrevealꢀtheꢀrela‐
tionshipꢀbetweenꢀtheꢀnatureꢀofꢀcatalystꢀandꢀitsꢀcatalyticꢀperformance.ꢀItꢀwasꢀfoundꢀthatꢀtheꢀcatalyticꢀ
performanceꢀ significantlyꢀ dependedꢀ onꢀ theꢀ texturalꢀ featuresꢀ andꢀ acidicꢀ properties,ꢀ whichꢀ wereꢀ
stronglyꢀaffectedꢀbyꢀpreparationꢀconditionsꢀofꢀtheꢀmeso‐La0.1Zr0.9
sitesꢀandꢀhighꢀaccessibilityꢀwereꢀrequiredꢀtoꢀobtainꢀsatisfactoryꢀcatalyticꢀreactionsꢀforꢀthisꢀreaction.ꢀ
Itꢀwasꢀalsoꢀfoundꢀthatꢀtheꢀaverageꢀcrystalliteꢀsizeꢀofꢀt‐ZrO ꢀaffectedꢀbyꢀtheꢀpreparationꢀconditionsꢀ
hadꢀ significantꢀ influenceꢀ onꢀ theꢀ ultrastrongꢀ acidicꢀ sitesꢀ ofꢀ theꢀ catalysts.ꢀ Theꢀ optimizedꢀ
SO 2
ꢀcatalystꢀexhibitedꢀmuchꢀsuperiorꢀcatalyticꢀactivityꢀandꢀcoke‐resistantꢀstabil‐
ity.ꢀMoreover,ꢀtheꢀdevelopedꢀSO 2
ꢀcatalystꢀdemonstratedꢀexcellentꢀcatalyticꢀper‐
O ꢀcomposite.ꢀAppropriateꢀacidicꢀ
δ
2
ꢀ
−/meso‐La0.1Zr0.9
O
δ
4
−/meso‐La0.1Zr0.9
O
δ
4
formanceꢀ forꢀ alkenylationꢀ ofꢀ diverseꢀ aromaticsꢀ withꢀ phenylacetyleneꢀ toꢀ theirꢀ correspondingꢀ
α‐arylstyrenes.ꢀCombiningꢀtheꢀpreviouslyꢀestablishedꢀcompleteꢀregenerationꢀofꢀusedꢀcatalystsꢀbyꢀaꢀ
facileꢀ calcinationꢀ processꢀ withꢀ theꢀ improvedꢀ catalyticꢀ properties,ꢀ theꢀ developedꢀ
SO 2
−/meso‐La0.1Zr0.9
4
δ
O ꢀ solidꢀ acidꢀ couldꢀ beꢀ aꢀ potentialꢀ catalystꢀ forꢀ industrialꢀ productionꢀ ofꢀ
α‐arylstyrenesꢀthroughꢀcleanꢀandꢀatomꢀefficientꢀsolid‐acid‐mediatedꢀFriedel‐Craftsꢀalkenylationꢀofꢀ
diverseꢀaromaticsꢀwithꢀphenylacetylene.ꢀ
©ꢀ2016,ꢀDalianꢀInstituteꢀofꢀChemicalꢀPhysics,ꢀChineseꢀAcademyꢀofꢀSciences.
PublishedꢀbyꢀElsevierꢀB.V.ꢀAllꢀrightsꢀreserved.
1
.ꢀ ꢀ Introductionꢀ
tractedꢀ aꢀ lotꢀ ofꢀ attentionꢀ owingꢀ toꢀ itsꢀ direct,ꢀ environmentallyꢀ
benign,ꢀandꢀatomꢀeconomicꢀcharacteristicsꢀforꢀtheꢀsynthesisꢀofꢀ
alkenylꢀ aromaticꢀ compoundsꢀ thatꢀ serveꢀ asꢀ industriallyꢀ im‐
Friedel‐Craftsꢀ alkenylationꢀ ofꢀ aromaticꢀ compoundsꢀ hasꢀ at‐
*ꢀCorrespondingꢀauthor.ꢀTel/Fax:ꢀ+86‐411‐84986354;ꢀE‐mail:ꢀzkzhao@dlut.edu.cnꢀ ꢀ
ThisꢀworkꢀwasꢀfinanciallyꢀsupportedꢀbyꢀtheꢀNationalꢀNaturalꢀScienceꢀFoundationꢀofꢀChinaꢀ(21276041),ꢀtheꢀProgramꢀforꢀNewꢀCenturyꢀExcellentꢀTal‐
entsꢀinꢀUniversityꢀofꢀMinistryꢀofꢀEducationꢀ(NCET‐12‐0079),ꢀtheꢀNaturalꢀScienceꢀFoundationꢀofꢀLiaoningꢀProvinceꢀ(2015020200),ꢀandꢀtheꢀFundamen‐
talꢀResearchꢀFundsꢀforꢀtheꢀCentralꢀUniversitiesꢀ(DUT15LK41).ꢀ ꢀ
DOI:ꢀ10.1016/S1872‐2067(15)61118‐4ꢀ|ꢀhttp://www.sciencedirect.com/science/journal/18722067ꢀ|ꢀChin.ꢀJ.ꢀCatal.,ꢀVol.ꢀ37,ꢀNo.ꢀ8,ꢀAugustꢀ2016ꢀ ꢀ ꢀ

1304ꢀ
ZhongkuiꢀZhaoꢀetꢀal.ꢀ/ꢀChineseꢀJournalꢀofꢀCatalysisꢀ37ꢀ(2016)ꢀ1303–1313ꢀ
portantꢀorganicꢀintermediatesꢀforꢀdyes,ꢀpigments,ꢀpharmaceu‐
ticals,ꢀ flavors,ꢀ agrochemicals,ꢀ andꢀ naturalꢀ productsꢀ [1].ꢀ Theꢀ
acid‐mediatedꢀalkenylationꢀofꢀaromaticsꢀhasꢀbeenꢀconsideredꢀaꢀ
promisingꢀapproachꢀforꢀtheꢀsynthesisꢀofꢀalkenylꢀaromaticsꢀow‐
ingꢀtoꢀitsꢀlowꢀcostꢀandꢀhighꢀactivityꢀ[2–8].ꢀ
superꢀacidsꢀhaveꢀbeenꢀinvestigatedꢀandꢀusedꢀinꢀdiverseꢀorganicꢀ
transformationsꢀ[19–34].ꢀThereꢀhaveꢀonlyꢀbeenꢀaꢀfewꢀreportsꢀofꢀ
alkenylationꢀ overꢀ solidꢀ superacids.ꢀ Weꢀ previouslyꢀ demon‐
stratedꢀthatꢀSO
4
2−/meso‐La
2
O
3
‐ZrO ꢀcouldꢀbeꢀaꢀpromisingꢀsolidꢀ
2
acidꢀ catalystꢀ forꢀ theꢀ alkenylationꢀ ofꢀ p‐xyleneꢀ [16].ꢀ However,ꢀ
althoughꢀtheꢀcatalystꢀcouldꢀbeꢀregeneratedꢀbyꢀcalcination,ꢀfur‐
therꢀimprovementꢀinꢀbothꢀcatalyticꢀactivityꢀandꢀstabilityꢀisꢀre‐
quired.ꢀOnꢀtheꢀwhole,ꢀtheꢀFriedel‐Craftsꢀalkenylationꢀreactionsꢀ
overꢀsolidꢀacidꢀcatalystsꢀhaveꢀbeenꢀscarcelyꢀreported,ꢀalthoughꢀ
thisꢀstrategyꢀcouldꢀbeꢀaꢀpromisingꢀapproachꢀforꢀtheꢀsynthesisꢀofꢀ
1,1‐diarylalkenesꢀ withꢀ easyꢀ separation,ꢀ green,ꢀ andꢀ atomꢀ effi‐
cientꢀ features.ꢀ Therefore,ꢀ theꢀ developmentꢀ ofꢀ novel,ꢀ low‐cost,ꢀ
andꢀrobustꢀsolidꢀacidꢀcatalystsꢀforꢀFriedel‐Craftsꢀalkenylationꢀisꢀ
highlyꢀdesirable,ꢀbutꢀstillꢀremainsꢀaꢀchallenge.ꢀ ꢀ
Solidꢀacidꢀ catalysisꢀ presentsꢀaꢀ promisingꢀrouteꢀ forꢀdiverseꢀ
acid‐mediatedꢀ organicꢀ transformationsꢀ owingꢀ toꢀ itsꢀ keyꢀ fea‐
turesꢀ suchꢀ asꢀ cleanꢀreactions,ꢀ easyꢀ separation,ꢀ catalystꢀreusa‐
bility,ꢀ andꢀ applicabilityꢀ inꢀ largeꢀ scaleꢀ continuousꢀ production.ꢀ
Recently,ꢀzeolitesꢀareꢀmoreꢀandꢀmoreꢀregardedꢀasꢀanꢀenviron‐
mentallyꢀbenignꢀsolidꢀacidꢀcatalystꢀforꢀFriedel‐Craftsꢀalkylationꢀ
inꢀbothꢀacademicꢀandꢀindustrialꢀfieldsꢀ[9–11].ꢀHowever,ꢀinꢀcon‐
trastꢀtoꢀtheꢀFriedel‐Craftsꢀalkylation,ꢀthereꢀareꢀstillꢀmanyꢀchal‐
lengesꢀthatꢀneedꢀtoꢀbeꢀresolvedꢀforꢀFriedel‐Craftsꢀalkenylation.ꢀ
Theꢀbiggestꢀchallengeꢀisꢀtoꢀefficientlyꢀpreventꢀtheꢀoligomeriza‐
tionꢀ andꢀ deepꢀ polymerizationꢀ ofꢀ alkynesꢀ resultingꢀ fromꢀ theꢀ
lowerꢀstabilityꢀofꢀtheꢀalkenylꢀcationꢀspeciesꢀcomparedꢀwithꢀthatꢀ
ofꢀtheꢀalkylꢀcationꢀintermediatesꢀ[12–16].ꢀUntilꢀnow,ꢀthereꢀhaveꢀ
onlyꢀ beenꢀ aꢀ fewꢀ reportsꢀ onꢀ alkenylationꢀ overꢀ solidꢀ acidꢀ cata‐
lysts.ꢀSartoriꢀandꢀco‐workersꢀ[17]ꢀpublishedꢀaꢀpioneeringꢀworkꢀ
onꢀtheꢀalkenylationꢀofꢀaromaticsꢀoverꢀHSZ‐360ꢀzeolite.ꢀUnfor‐
tunately,ꢀtheꢀresultsꢀwereꢀnotꢀsatisfactory,ꢀandꢀanꢀirreconcilableꢀ
contradictionꢀexistedꢀbetweenꢀselectivityꢀandꢀcatalyticꢀactivity:ꢀ
theꢀzeoliteꢀcatalystsꢀsufferedꢀfromꢀaꢀcalcinationꢀprocessꢀatꢀlow‐
erꢀtemperatureꢀandꢀexhibitedꢀhighꢀcatalyticꢀactivity,ꢀbutꢀitꢀre‐
sultedꢀ inꢀ theꢀ formationꢀ ofꢀ aꢀ largeꢀ amountꢀ ofꢀ acetophenoneꢀ
BasedꢀonꢀourꢀpreviouslyꢀdevelopedꢀSO
solidꢀacidꢀcatalyst,ꢀtheꢀtuningꢀofꢀtheꢀacidicꢀsitesꢀandꢀtheirꢀacces‐
sibilityꢀwasꢀinvestigatedꢀbyꢀregulatingꢀtheꢀtexturalꢀfeaturesꢀandꢀ
acidicꢀpropertiesꢀofꢀSO ꢀsolidꢀacids.ꢀVariousꢀ
characterizationꢀ techniquesꢀ includingꢀ N ꢀ physisorption,ꢀ X‐rayꢀ
diffractionꢀ (XRD),ꢀ NH ꢀ temperature‐programmedꢀ desorptionꢀ
(NH ‐TPD),ꢀ andꢀ thermogravimetricꢀ analysisꢀ (TGA)ꢀ wereꢀ em‐
4
2−/meso‐La0.1Zr0.9
δ
O ꢀ
2−/meso‐La0.1Zr0.9
O
4
δ
2
3
3
ployedꢀ toꢀ exploreꢀ theꢀ relationshipꢀ betweenꢀ theꢀ natureꢀ ofꢀ theꢀ
catalystꢀandꢀitsꢀcatalyticꢀperformanceꢀinꢀFriedel‐Craftsꢀalkenyl‐
ation.ꢀItꢀwasꢀfoundꢀthatꢀtheꢀtexturalꢀfeaturesꢀandꢀacidicꢀproper‐
tiesꢀ ofꢀ SO
modulatedꢀbyꢀchangingꢀtheꢀpreparationꢀconditionsꢀofꢀtheꢀme‐
ꢀcomposite.ꢀAsꢀaꢀconsequence,ꢀtheꢀcatalyticꢀper‐
formanceꢀ ofꢀ theꢀ SO ꢀ solidꢀ acidꢀ catalystꢀ inꢀ
Friedel‐Craftsꢀalkenylationꢀwasꢀsignificantlyꢀimproved.ꢀMoreo‐
ver,ꢀ theꢀ developedꢀ SO ꢀ catalystꢀ demon‐
4
2−/meso‐La0.1Zr0.9
O ꢀ solidꢀ acidsꢀ canꢀ beꢀ efficientlyꢀ
δ
(5%–20%);ꢀ aꢀ higherꢀ calcinationꢀ temperatureꢀ efficientlyꢀ sup‐
so‐La0.1Zr0.9
O
δ
pressedꢀ theꢀ formationꢀ ofꢀ acetophenoneꢀ alongꢀ withꢀ alkenyla‐
tion,ꢀ butꢀ itꢀ ledꢀ toꢀ aꢀ remarkableꢀ decreaseꢀ inꢀ catalyticꢀ activity.ꢀ
Moreover,ꢀtheꢀenlargementꢀinꢀscopeꢀofꢀsubstratesꢀisꢀalsoꢀdesir‐
able.ꢀTheꢀcatalyticꢀefficiencyꢀofꢀtheꢀzeolite‐catalyzedꢀalkenyla‐
tionꢀwasꢀnotꢀhigh;ꢀ1.0ꢀgꢀofꢀzeoliteꢀwasꢀrequiredꢀforꢀtransform‐
ingꢀlessꢀthanꢀ1.0ꢀgꢀofꢀphenylacetylene.ꢀTheꢀpossibleꢀreasonꢀwasꢀ
thatꢀtheꢀreactionꢀonlyꢀtookꢀplaceꢀonꢀtheꢀexternalꢀsurfaceꢀofꢀtheꢀ
catalystꢀ becauseꢀ ofꢀ theꢀ narrowꢀ poreꢀ channelsꢀ withinꢀ theꢀ HYꢀ
zeoliteꢀ [14,18].ꢀ Mesoporousꢀ solidꢀ acidsꢀ couldꢀ beꢀ promisingꢀ
candidatesꢀ forꢀ Friedel‐Craftsꢀ alkenylation.ꢀ Itꢀ hasꢀ previouslyꢀ
beenꢀdemonstratedꢀthatꢀaꢀFe‐containingꢀmesoporousꢀalumino‐
silicateꢀ exhibitedꢀ veryꢀ highꢀ activityꢀ forꢀ theꢀ Friedel‐Craftsꢀ
alkenylationꢀ ofꢀ phenolsꢀ withꢀ aryl‐substitutedꢀ alkynesꢀ underꢀ
mildꢀconditionsꢀ[19].ꢀHowever,ꢀaꢀfurtherꢀincreaseꢀinꢀselectivityꢀ
isꢀdesirable.ꢀ ꢀ
4
2−/meso‐La0.1Zr0.9
O
δ
2−/meso‐La0.1Zr0.9
O
4
δ
stratedꢀ excellentꢀ catalyticꢀ performanceꢀ inꢀ theꢀ alkenylationꢀ ofꢀ
diverseꢀaromaticsꢀwithꢀphenylacetyleneꢀtoꢀtheirꢀcorrespondingꢀ
α‐arylstyrenes.ꢀInꢀcombinationꢀwithꢀtheꢀpreviouslyꢀestablishedꢀ
completeꢀregenerationꢀofꢀtheꢀusedꢀcatalystꢀbyꢀaꢀfacileꢀcalcina‐
tionꢀ treatmentꢀ andꢀ theꢀ improvedꢀ catalyticꢀ performanceꢀ re‐
portedꢀinꢀthisꢀwork,ꢀtheꢀoptimizedꢀSO
4
2−/meso‐La0.1Zr0.9
O ꢀsolidꢀ
δ
acidꢀcouldꢀbeꢀaꢀpotentialꢀcatalystꢀforꢀtheꢀalkenylationꢀofꢀdiverseꢀ
aromaticsꢀ withꢀ phenylacetyleneꢀ toꢀ theirꢀ correspondingꢀ
α‐arylstyrenes.ꢀ ꢀ
2.ꢀ ꢀ Experimentalꢀ
Weꢀ haveꢀ previouslyꢀ developedꢀ H
supportedꢀonꢀMCM‐41ꢀforꢀtheꢀalkenylationꢀofꢀdiverseꢀaromaticsꢀ
13].ꢀHowever,ꢀfurtherꢀimprovementꢀinꢀcatalyticꢀactivity,ꢀselec‐
3
PW12
O
40ꢀ(HPA)ꢀcatalystsꢀ
2.1.ꢀ ꢀ Catalystꢀpreparationꢀ
[
MesoporousꢀLa0.1Zr0.9O ꢀcompositeꢀoxidesꢀwereꢀsynthesizedꢀ
δ
tivity,ꢀandꢀexpansionꢀinꢀtheꢀscopeꢀofꢀtheꢀreactantsꢀisꢀindispen‐
sable.ꢀMoreover,ꢀtheꢀcomplexityꢀandꢀhighꢀcostꢀofꢀtheꢀprepara‐
tionꢀprocessꢀofꢀmesoporousꢀsilicaꢀlimitsꢀitsꢀpotentialꢀapplicationꢀ
inꢀtheꢀproductionꢀofꢀα‐arylstyrenesꢀusingꢀsolidꢀacid‐catalyzedꢀ
alkenylation.ꢀTheꢀsupportedꢀHPAꢀcatalystꢀonꢀactivatedꢀcarbonꢀ
wasꢀdevelopedꢀtoꢀaddressꢀtheꢀhighꢀcostꢀissueꢀassociatedꢀwithꢀ
HPA/MCM‐41ꢀ[15].ꢀTheꢀefficientꢀregenerationꢀofꢀtheꢀdeactivat‐
edꢀ catalystꢀ byꢀ washingꢀ withꢀ aꢀ polarꢀ solventꢀ mightꢀ requireꢀ aꢀ
largeꢀamountꢀofꢀevaporableꢀsolvent,ꢀwhichꢀwouldꢀconsequentlyꢀ
produceꢀ anꢀ environmentalꢀ issueꢀ inꢀ additionꢀ toꢀ theꢀ possibleꢀ
leachingꢀofꢀHPAꢀbyꢀtheꢀpolarꢀsolvent.ꢀOwingꢀtoꢀtheirꢀrelativelyꢀ
highꢀ thermalꢀ stabilityꢀ andꢀ strongꢀ acidicꢀ sites,ꢀ sulfatedꢀ solidꢀ
byꢀ theꢀ previouslyꢀ reportedꢀ surfactant‐assistedꢀ hydrothermalꢀ
crystallizationꢀ methodꢀ [16].ꢀ Typically,ꢀ theꢀ zirconiumꢀ nitrateꢀ
(AR,ꢀ Sinopharmꢀ Group,ꢀ China)ꢀ andꢀ lanthanumꢀ nitrateꢀ (AR,ꢀ
TianjinꢀGuangfuꢀInstitute,ꢀChina)ꢀwithꢀaꢀ9:1ꢀmolarꢀratioꢀofꢀZrꢀtoꢀ
Laꢀ wereꢀ dissolvedꢀ inꢀ deionizedꢀ water.ꢀ Aꢀ certainꢀ amountꢀ ofꢀ
CTABꢀ(AR,ꢀKermel,ꢀChina)ꢀwithꢀvariousꢀmolarꢀratiosꢀofꢀCTABꢀtoꢀ
metalꢀ ionsꢀ (Nt/mꢀ =ꢀ 0.10,ꢀ 0.13,ꢀ 0.15,ꢀ 0.18,ꢀ andꢀ 0.20)ꢀ wasꢀ dis‐
solvedꢀ inꢀ deionizedꢀ waterꢀ toꢀ giveꢀ aꢀ clearꢀ homogeneousꢀ solu‐
tion.ꢀ Theꢀ twoꢀ solutionsꢀ wereꢀ thenꢀ mixedꢀ underꢀ continuousꢀ
stirring.ꢀSubsequently,ꢀvariousꢀamountsꢀofꢀanꢀammoniumꢀsolu‐
tionꢀ(Na/mꢀ=ꢀ14,ꢀ16,ꢀ18,ꢀ20)ꢀwereꢀaddedꢀdropwiseꢀintoꢀtheꢀmix‐
ture.ꢀ Afterꢀ precipitation,ꢀ theꢀ gelatinousꢀ paleꢀ mixtureꢀ wasꢀ

ꢀ
ZhongkuiꢀZhaoꢀetꢀal.ꢀ/ꢀChineseꢀJournalꢀofꢀCatalysisꢀ37ꢀ(2016)ꢀ1303–1313ꢀ
1305ꢀ
stirredꢀforꢀanotherꢀ4ꢀhꢀfollowedꢀbyꢀaꢀhydrothermalꢀcrystalliza‐
tionꢀprocessꢀatꢀvariousꢀhydrothermalꢀtemperaturesꢀ(Thydroꢀ=ꢀ75,ꢀ
thenꢀ evacuatedꢀ atꢀ 150ꢀ andꢀ 450ꢀ °Cꢀ forꢀ 30ꢀ minꢀ andꢀ aꢀ corre‐
spondingꢀ spectrumꢀ wasꢀ recordedꢀ toꢀ distinguishꢀ theꢀ acidꢀ site.ꢀ
Theꢀ relativeꢀ intensitiesꢀ ofꢀ theꢀ vibrationꢀ bandsꢀ atꢀ 1540ꢀ ꢀ andꢀ
90,ꢀ105,ꢀandꢀ120ꢀ°C)ꢀforꢀdifferentꢀhydrothermalꢀtimeꢀ(thydroꢀ=ꢀ
−1
36,ꢀ60,ꢀandꢀ84ꢀh)ꢀinꢀaꢀsealedꢀTeflonꢀautoclave.ꢀTheꢀsolidꢀproductꢀ
1450ꢀcm ꢀwereꢀassignedꢀtoꢀtheꢀBꢀandꢀLꢀacidꢀsites,ꢀrespectively.ꢀ
wasꢀfiltered,ꢀwashed,ꢀdried,ꢀandꢀthenꢀcalcinedꢀinꢀaꢀmuffleꢀfur‐
naceꢀ atꢀ 550ꢀ °Cꢀ forꢀ 6ꢀ hꢀ toꢀ obtainꢀ aꢀ seriesꢀ ofꢀ mesoporousꢀ
2.3.ꢀ ꢀ Catalystꢀperformanceꢀtestꢀ
La0.1Zr0.9
O
δ
ꢀ compositeꢀ oxides.ꢀ Theꢀ variousꢀ SO
4
2−/meso‐
ꢀ
La0.1Zr0.9
O
δ
ꢀsolidꢀacidꢀcatalystꢀsamplesꢀwithꢀdifferentꢀNt/m,ꢀNa/m,ꢀ
Theꢀcatalyticꢀperformanceꢀmeasurementsꢀforꢀtheꢀalkenyla‐
tionꢀ ofꢀ p‐xyleneꢀ withꢀ phenylacetyleneꢀ wasꢀ performedꢀ inꢀ aꢀ
stainlessꢀsteelꢀfixed‐bedꢀcontinuous‐flowꢀreactor.ꢀInꢀtotal,ꢀ1.0ꢀgꢀ
ofꢀcatalystꢀpressedꢀintoꢀtabletsꢀandꢀsievedꢀintoꢀ20‒60ꢀmeshꢀwasꢀ
loadedꢀ intoꢀ theꢀ reactorꢀ forꢀ allꢀ theꢀ reactionꢀ tests,ꢀ andꢀ theꢀ re‐
mainingꢀspaceꢀofꢀtheꢀreactorꢀtubeꢀwasꢀfilledꢀwithꢀ20‒60ꢀmeshꢀ
quartzꢀgranules.ꢀBeforeꢀtheꢀintroductionꢀofꢀfeedstock,ꢀtheꢀcata‐
T
hydro,ꢀ andꢀ thydroꢀ wereꢀ preparedꢀ byꢀ theꢀ impregnationꢀ methodꢀ
withꢀH SO ꢀ(1ꢀmol/L)ꢀasꢀimpregnantꢀandꢀaꢀsubsequentꢀdryingꢀ
andꢀcalcinationꢀprocess.ꢀ ꢀ
2
4
2.2.ꢀ ꢀ Catalystꢀcharacterizationꢀ
Nitrogenꢀ physisorptionꢀ experimentsꢀ wereꢀ performedꢀ atꢀ
196ꢀ°CꢀonꢀaꢀBeiShiDeꢀ3H‐2000PS1ꢀsurfaceꢀareaꢀporosityꢀana‐
lystꢀ wasꢀ pre‐activatedꢀ inꢀ situꢀ forꢀ 1ꢀ hꢀ underꢀ aꢀ N
mL/min.ꢀTheꢀliquidꢀstreamꢀwasꢀintroducedꢀintoꢀtheꢀfixed‐bedꢀ
reactorꢀbyꢀaꢀsyringeꢀpump.ꢀN ꢀ(99.999%ꢀpurity)ꢀwasꢀusedꢀtoꢀ
2
ꢀ flowꢀ atꢀ 30ꢀ
−
lyzer.ꢀ Theꢀ specificꢀ surfaceꢀ areaꢀ wasꢀ calculatedꢀ byꢀ theꢀ BETꢀ
methodꢀ andꢀ theꢀ poreꢀ sizeꢀ distributionꢀ wasꢀ calculatedꢀ byꢀ theꢀ
Barrett‐Joyner‐Halendaꢀ (BJH)ꢀ modelꢀ fromꢀ theꢀ desorptionꢀ
branchꢀ ofꢀ theꢀ isotherms.ꢀ Theꢀ cokeꢀ amountꢀ depositedꢀ onꢀ theꢀ
spentꢀ catalystsꢀ wasꢀ obtainedꢀ byꢀ TGAꢀ analysisꢀ usingꢀ aꢀ Perki‐
2
maintainꢀsystemꢀpressure.ꢀQuantitativeꢀanalysisꢀofꢀtheꢀcollectedꢀ
reactionꢀmixtureꢀfromꢀtheꢀfixed‐bedꢀreactorꢀwasꢀperformedꢀonꢀ
aꢀFULIꢀ9790ꢀIIꢀGCꢀequippedꢀwithꢀanꢀHP‐5ꢀcolumnꢀ(30ꢀmꢀ×ꢀ0.32ꢀ
mmꢀ×ꢀ0.25ꢀμm),ꢀandꢀanꢀFIDꢀdetector.ꢀAsꢀanꢀevaluationꢀstandardꢀ
ofꢀ theꢀ alkenylationꢀ reaction,ꢀ theꢀ phenylacetyleneꢀ conversionꢀ
wasꢀ calculatedꢀ byꢀ massꢀ percentageꢀ ofꢀ theꢀ transformedꢀ phe‐
nylacetyleneꢀ fromꢀ theꢀ totalꢀ amountꢀ ofꢀ phenylacetyleneꢀ intro‐
ducedꢀinꢀtheꢀfeed.ꢀBasedꢀonꢀtheꢀGC‐MSꢀdataꢀandꢀourꢀpreviousꢀ
workꢀ [13–16],ꢀ besidesꢀ theꢀ mainꢀ productꢀ α‐arylstyreneꢀ (I),ꢀ aꢀ
seriesꢀ ofꢀ byproductsꢀ suchꢀ asꢀ acetophenoneꢀ (II),ꢀ
β‐(2,5‐dimethylphenyl)ꢀ styreneꢀ (III),ꢀ α‐(2,5‐dimethylphenyl)ꢀ
ethylbenzeneꢀ(IV),ꢀandꢀoligomersꢀ(V)ꢀwereꢀdetected,ꢀindicatingꢀ
theꢀalkenylationꢀreactionꢀofꢀp‐xyleneꢀwithꢀphenylacetyleneꢀisꢀaꢀ
quiteꢀ complexꢀ competitionꢀ process.ꢀ Besidesꢀ theꢀ alkenylation,ꢀ
manyꢀ sideꢀ reactions,ꢀ suchꢀ asꢀ hydrationꢀ ofꢀ phenylacetylene,ꢀ
hydrogenationꢀ ofꢀ α‐arylstyrene,ꢀ thermodynamicꢀ controlꢀ
alkenylation,ꢀandꢀtheꢀoligomerizationꢀreactionsꢀtakeꢀplaceꢀsim‐
ultaneously.ꢀTheꢀscopeꢀofꢀtheꢀsubstratesꢀthatꢀcanꢀbeꢀusedꢀforꢀ
theꢀ developedꢀ solidꢀ superacidꢀ catalyst‐mediatedꢀ alkenylationꢀ
wasꢀinvestigatedꢀbyꢀemployingꢀaꢀdiverseꢀrangeꢀofꢀaromaticsꢀasꢀ
substrates.ꢀ
−1
nElmerꢀSTAꢀ6000ꢀwithꢀaꢀheatingꢀrateꢀofꢀ10ꢀ°Cꢀmin ꢀfromꢀ30ꢀtoꢀ
00ꢀ°Cꢀinꢀanꢀairꢀstream.ꢀXRDꢀpatternsꢀofꢀtheꢀsamplesꢀwereꢀrec‐
ordedꢀfromꢀ0°ꢀtoꢀ10°ꢀandꢀ10°ꢀtoꢀ80°ꢀwithꢀaꢀstepꢀwidthꢀofꢀ0.02°ꢀ
usingꢀaꢀRigakuꢀD/max‐2400ꢀapparatusꢀusingꢀCuꢀK ꢀradiation.ꢀ
NH ‐TPDꢀ measurementsꢀ wereꢀ performedꢀ toꢀ characterizeꢀ
8
α
3
theꢀacidicꢀpropertiesꢀofꢀtheꢀsamples.ꢀAfterꢀpre‐treatmentꢀofꢀ50ꢀ
mgꢀ samplesꢀinꢀ Arꢀ (heatingꢀtoꢀ 450ꢀ °Cꢀwithꢀ aꢀrampꢀ rateꢀofꢀ10ꢀ
°
C/min,ꢀthenꢀkeptꢀatꢀ450ꢀ°Cꢀforꢀ0.5ꢀhꢀunderꢀanꢀArꢀflowꢀofꢀ30ꢀ
mL/min),ꢀ theꢀ samplesꢀ wereꢀ saturatedꢀ withꢀ ammoniaꢀ (10%ꢀ
NH ‐90%ꢀAr)ꢀatꢀ100ꢀ°Cꢀusingꢀtheꢀpulseꢀinjectionꢀmethod.ꢀFinal‐
ly,ꢀtheꢀNH ꢀdesorptionꢀstepꢀwasꢀperformedꢀfromꢀ100ꢀtoꢀ850ꢀ°Cꢀ
atꢀaꢀrampꢀrateꢀofꢀ10ꢀ°C/minꢀunderꢀanꢀArꢀflowꢀofꢀ30ꢀmL/min.ꢀ
Theꢀ NH ‐TPDꢀ profilesꢀ wereꢀ obtainedꢀ byꢀ monitoringꢀ theꢀ de‐
3
3
3
sorbedꢀammoniaꢀwithꢀaꢀthermalꢀconductivityꢀdetector.ꢀ ꢀ
TheꢀXPSꢀexperimentsꢀofꢀtheꢀfreshꢀandꢀspentꢀsolidꢀacidꢀcata‐
lystsꢀwereꢀperformedꢀonꢀanꢀESCALABꢀ250ꢀXPSꢀsystemꢀwithꢀaꢀ
monochromatizedꢀAlꢀK ꢀX‐rayꢀsourceꢀ(15ꢀkV,ꢀ150ꢀW,ꢀ500ꢀµm,ꢀ
α
passꢀenergyꢀ=ꢀ 50ꢀ eV).ꢀTheꢀbindingꢀenergyꢀ wasꢀ calibratedꢀac‐
cordingꢀ toꢀ theꢀ Cꢀ 1sꢀ photoelectronꢀ peakꢀ atꢀ 284.6ꢀ eV,ꢀ andꢀ theꢀ
bindingꢀenergyꢀofꢀSꢀ2pꢀwasꢀanalyzedꢀatꢀ152–175ꢀeV,ꢀusingꢀtheꢀ
Shirleyꢀbaseline‐correctionꢀmethod.ꢀ ꢀ
3.ꢀ ꢀ Resultsꢀandꢀdiscussionꢀ
3.1.ꢀ ꢀ Effectꢀofꢀtheꢀmolarꢀratioꢀofꢀtemplateꢀtoꢀmetalꢀionsꢀ
Theꢀtypeꢀofꢀacidꢀsitesꢀ(Brönstedꢀ(B)ꢀandꢀLewisꢀ(L))ꢀandꢀrela‐
tiveꢀamountꢀ(B/L)ꢀwereꢀmeasuredꢀbyꢀPy‐IR.ꢀTheꢀPy‐IRꢀspectraꢀ
wereꢀrecordedꢀatꢀroomꢀtemperatureꢀinꢀtheꢀwavenumberꢀrangeꢀ
ofꢀ 1590–1410ꢀ cm ꢀonꢀanꢀEQUINOX‐55ꢀFourierꢀtransformꢀin‐
fraredꢀ spectrometerꢀ (BRUKER).ꢀ Theꢀ as‐preparedꢀ solidꢀ acidꢀ
catalystsꢀ wereꢀ pressedꢀ intoꢀ aꢀ self‐supportingꢀ waferꢀ (ca.ꢀ 15ꢀ
Tableꢀ1ꢀpresentsꢀtheꢀresultsꢀofꢀalkenylationꢀofꢀp‐xyleneꢀwithꢀ
Tableꢀ1ꢀ
−1
Effectꢀ ofꢀ theꢀ
N
t/m
ꢀ
valueꢀ onꢀ theꢀ catalyticꢀ performanceꢀ ofꢀ
ꢀ solidꢀ acidꢀ catalystsꢀ forꢀ theꢀ alkenylationꢀ ofꢀ
2−
SO
4
/meso‐La0.1Zr0.9
O
δ
p‐xyleneꢀwithꢀphenylacetylene.ꢀ
mg/cm),ꢀ andꢀ introducedꢀ intoꢀ aꢀ quartzꢀ IRꢀ cellꢀ withꢀ CaF ꢀ win‐
2
Conv.ꢀ
Productꢀdistributionꢀ(%)ꢀ
N ꢀ
t/m
dows.ꢀ Theꢀ samplesꢀ wereꢀ pretreatedꢀ inꢀ situꢀ byꢀ heatingꢀ inꢀ aꢀ
(%)ꢀ
Iꢀ
IIꢀ
IIIꢀ
5.0ꢀ
IVꢀ
0.1ꢀ
Vꢀ
ꢀ
streamꢀofꢀheliumꢀatꢀ30ꢀmL/minfromꢀroomꢀtemperatureꢀtoꢀ450ꢀ
0.10ꢀ
0.13ꢀ
0.15ꢀ
80.2ꢀ
82.7ꢀ
85.1ꢀ
91.6ꢀ
91.7ꢀ
93.5ꢀ
93.6ꢀ
93.1ꢀ
93.7ꢀ
92.3ꢀ
0.1ꢀ
0.2ꢀ
0.2ꢀ
0.1ꢀ
0.2ꢀ
1.3ꢀ
1.5ꢀ
2.6ꢀ
3.0ꢀ
2.8ꢀ
−3
°
Cꢀandꢀ5ꢀ×ꢀ10 ꢀPaꢀforꢀ30ꢀmin.ꢀTheꢀcellꢀwasꢀsubsequentlyꢀcooledꢀ
4.6ꢀ
0.1ꢀ
toꢀroomꢀtemperatureꢀandꢀpyridineꢀvaporꢀwasꢀpassedꢀintoꢀtheꢀ
cellꢀ andꢀ adsorbedꢀ ontoꢀ theꢀ optimizedꢀ (inꢀ thisꢀ work)ꢀ andꢀ theꢀ
4.0ꢀ
0.1ꢀ
0.18ꢀ
0.20ꢀ
3.0ꢀ
0.2ꢀ
unoptimizedꢀ (previouslyꢀ developed)ꢀ SO 2
−/meso‐La0.1Zr0.9
O ꢀ
4
δ
4.6ꢀ
0.1ꢀ
solidꢀacidꢀcatalystsꢀforꢀaꢀperiodꢀofꢀ30ꢀmin.ꢀAfterꢀremovalꢀofꢀtheꢀ
excessꢀ pyridine,ꢀtheꢀspectrumꢀ wasꢀrecorded.ꢀ Theꢀ sampleꢀwasꢀ
Reactionꢀconditions:ꢀcatalystꢀ1.0ꢀg,ꢀnAr/
MPa,ꢀVHSVꢀ=ꢀ6ꢀmL/(gcat·h),ꢀTOSꢀ=ꢀ8ꢀh.ꢀ
n
Phenꢀ=ꢀ25,ꢀT
r
ꢀ=ꢀ150ꢀ°C,ꢀP ꢀ=ꢀ1.0ꢀ
s

1306ꢀ
ZhongkuiꢀZhaoꢀetꢀal.ꢀ/ꢀChineseꢀJournalꢀofꢀCatalysisꢀ37ꢀ(2016)ꢀ1303–1313ꢀ
phenylacetyleneꢀ overꢀ theꢀ SO
4
2−/meso‐La0.1Zr0.9
O ꢀ solidꢀ acidsꢀ
δ
Tableꢀ2ꢀ
preparedꢀwithꢀvariousꢀmolarꢀratiosꢀofꢀtheꢀtemplateꢀ(CTAB)ꢀtoꢀ
theꢀtotalꢀmetalꢀionsꢀcontainingꢀLaꢀandꢀZrꢀ(Nt/m).ꢀForꢀthisꢀprepa‐
Effectꢀ ofꢀ N ꢀ valueꢀ onꢀ theꢀ CS ꢀ andꢀ Vtotalꢀ ofꢀ theꢀ as‐synthesizedꢀ
t/m
Zr
SO
4
2−/meso‐La0.1Zr0.9
2
O ꢀsolidꢀacidꢀcatalyst.ꢀ
rationꢀprocess,ꢀtheꢀ18ꢀofꢀNa/m,ꢀ105ꢀ°CꢀofꢀThydro,ꢀandꢀ60ꢀhꢀofꢀthydro
ꢀ
N
t/m
ꢀ
CSZrꢀaꢀ(nm)ꢀ
V
totalꢀbꢀ(cm
3
/g)ꢀ
wereꢀused.ꢀItꢀcanꢀbeꢀobservedꢀthatꢀtheꢀconversionꢀofꢀphenyla‐
0.15ꢀ
6.1ꢀ
5.9ꢀ
5.8ꢀ
0.36ꢀ
0.35ꢀ
0.34ꢀ
b
0
0
.18ꢀ
.20ꢀ
cetyleneꢀincreasesꢀwithꢀtheꢀincreaseꢀofꢀNt/mꢀfromꢀ0.10ꢀtoꢀ0.18.ꢀ
Asꢀ theꢀ Nt/mꢀ increasesꢀ furtherꢀ theꢀ conversionꢀ remainsꢀ almostꢀ
unchanged.ꢀ91.6%ꢀofꢀ phenylacetyleneꢀconversionꢀwithꢀ93.1%ꢀ
ofꢀ theꢀ selectivityꢀ towardsꢀ theꢀ mainꢀ productꢀ
α‐(2,5‐dimethylphenyl)‐styreneꢀ canꢀ beꢀ obtainedꢀ whenꢀ Nt/mꢀ isꢀ
aꢀEstimatedꢀbyꢀScherrerꢀequationꢀfromꢀXRDꢀpatterns;ꢀ ꢀFromꢀN
sisorption.ꢀ
ꢀ
2
ꢀphy‐
0.20ꢀleadsꢀtoꢀanꢀincreaseꢀinꢀisomersꢀowingꢀtoꢀaꢀworseꢀdiffusionꢀ
0
.18.ꢀ Furthermore,ꢀ theꢀ Nt/mꢀ increasesꢀ upꢀ toꢀ 0.18ꢀ leadsꢀ toꢀ anꢀ
increaseꢀ inꢀ oligomersꢀ butꢀ aꢀ decreaseꢀ inꢀ isomerꢀ
β‐(2,5‐dimethylphenyl)ꢀ styrene).ꢀ However,ꢀ interestingly,ꢀ theꢀ
ofꢀtheꢀmainꢀproduct.ꢀFromꢀFig.ꢀ1(b),ꢀtheꢀNH ‐TPDꢀprofilesꢀcanꢀ
3
beꢀdividedꢀintoꢀfourꢀregionsꢀ(150–300,ꢀ300–450,ꢀ450–600,ꢀandꢀ
aboveꢀ600ꢀ°C),ꢀwhichꢀcanꢀbeꢀassignedꢀasꢀweak,ꢀmedium,ꢀstrong,ꢀ
andꢀsuperꢀacidicꢀsites,ꢀrespectively.ꢀTheꢀacidicꢀpropertiesꢀofꢀtheꢀ
sulfatedꢀ metalꢀ oxidesꢀ areꢀ dependentꢀ onꢀ theꢀ texturalꢀ featuresꢀ
andꢀtheꢀcrystallineꢀphase,ꢀbesidesꢀtheꢀcomponentꢀofꢀtheꢀoxidesꢀ
(
furtherꢀincreaseꢀofꢀNt/mꢀfromꢀ0.18ꢀtoꢀ0.2ꢀresultsꢀinꢀaꢀdecreaseꢀinꢀ
oligomersꢀbutꢀanꢀincreaseꢀinꢀisomers.ꢀConsideringꢀtheꢀreactionꢀ
resultsꢀandꢀtheꢀeconomicꢀefficiency,ꢀtheꢀoptimumꢀNt/mꢀisꢀ0.18.ꢀ ꢀ
Nitrogenꢀ physisorption,ꢀ NH ‐TPD,ꢀ andꢀ XRDꢀ experimentsꢀ
3
[19–34].ꢀTheꢀincreaseꢀofꢀtheꢀsurfaceꢀareaꢀasꢀNt/mꢀisꢀincreasedꢀ
wereꢀperformedꢀtoꢀrevealꢀtheꢀrelationshipꢀbetweenꢀtheꢀnatureꢀ
ofꢀtheꢀcatalystꢀandꢀitsꢀcatalyticꢀperformance.ꢀFig.ꢀ1ꢀpresentsꢀtheꢀ
adsorption‐desorptionꢀ isotherms,ꢀ poreꢀ sizeꢀ distributionsꢀ (Fig.ꢀ
fromꢀ0.15ꢀtoꢀ0.18ꢀleadsꢀtoꢀanꢀincreaseꢀinꢀtheꢀamountꢀofꢀacidicꢀ
sites,ꢀwhichꢀresultsꢀinꢀtheꢀincreasedꢀconversionꢀshownꢀinꢀTableꢀ
1.ꢀNoꢀobviousꢀchangeꢀinꢀweakꢀandꢀmediumꢀacidicꢀsitesꢀcanꢀbeꢀ
1
(a)),ꢀ andꢀ NH
3
‐TPDꢀ profilesꢀ (Fig.ꢀ 1(b))ꢀ ofꢀ theꢀ SO 2−/meso‐ꢀ
4
observedꢀ asꢀ theꢀ Nt/mꢀ isꢀ increasedꢀ furtherꢀ fromꢀ 0.18ꢀ toꢀ 0.20,ꢀ
whereasꢀ thereꢀ isꢀ anꢀ obviousꢀ decreaseꢀ inꢀ strongꢀ acidicꢀ sites.ꢀ
δ
La0.1Zr0.9O ꢀ solidꢀ acidsꢀ preparedꢀ withꢀ variousꢀ Nt/mꢀ values.ꢀ Asꢀ
shownꢀinꢀFig.ꢀ1(a),ꢀtheꢀtypeꢀIVꢀisothermꢀwithꢀaꢀhysteresisꢀloopꢀ
isꢀaꢀtypicalꢀfeatureꢀofꢀmesoporousꢀmaterialsꢀ[35,36],ꢀindicatingꢀ
theꢀ existenceꢀ ofꢀ aꢀ mesoporousꢀ structureꢀ inꢀ theꢀ as‐preparedꢀ
solidꢀ superacids.ꢀFromꢀtheꢀinsetꢀinꢀFig.ꢀ 1(a)ꢀandꢀTableꢀ 2,ꢀtheꢀ
increaseꢀofꢀNt/mꢀfromꢀ0.15ꢀtoꢀ0.18ꢀleadsꢀtoꢀanꢀincreaseꢀinꢀtheꢀ
FromꢀtheꢀreactionꢀresultsꢀinꢀTableꢀ1,ꢀtheꢀtwoꢀsamplesꢀwithꢀNt/m
ꢀ
ofꢀ 0.18ꢀ andꢀ 0.20ꢀ demonstrateꢀ similarꢀ catalyticꢀ activity,ꢀ sug‐
gestingꢀthatꢀtheꢀweakꢀ andꢀmediumꢀ acidicꢀ sitesꢀ areꢀ theꢀ activeꢀ
sitesꢀforꢀalkenylation.ꢀ ꢀ
FromꢀFig.ꢀ2,ꢀtheꢀpeaksꢀinꢀtheꢀXRDꢀpatternsꢀofꢀtheꢀthreeꢀsam‐
plesꢀatꢀ30.1°,ꢀ34.7°,ꢀ50.1°,ꢀ59.5°,ꢀandꢀ73.7°ꢀcanꢀbeꢀwell‐resolved,ꢀ
indexedꢀasꢀtheꢀ(011),ꢀ(110),ꢀ(112),ꢀ(121),ꢀandꢀ(123)ꢀplanesꢀofꢀ
2
surfaceꢀareaꢀfromꢀ76ꢀtoꢀ81ꢀm /gꢀandꢀtoꢀaꢀslightꢀdecreaseꢀinꢀtheꢀ
3
totalꢀporeꢀvolumeꢀ(Vtotal)ꢀfromꢀ0.36ꢀtoꢀ0.35ꢀcm /g,ꢀasꢀwellꢀasꢀanꢀ
increaseꢀinꢀtheꢀamountꢀofꢀmesopores.ꢀTheꢀfurtherꢀincreaseꢀofꢀ
tetragonalꢀ phaseꢀ ofꢀ ZrO
tionꢀpeaksꢀcorrespondingꢀtoꢀLa
observed,ꢀwhichꢀisꢀascribedꢀtoꢀtheꢀinsertionꢀofꢀLaꢀintoꢀtheꢀZrO
latticeꢀandꢀtheꢀledꢀstabilizationꢀeffectꢀonꢀt‐ZrO ꢀphaseꢀ[16,35].ꢀ
2
,ꢀ respectivelyꢀ [35,37–39].ꢀ Noꢀ diffrac‐
Nt/mꢀfromꢀ0.18ꢀtoꢀ0.20ꢀleadsꢀtoꢀanꢀincreaseꢀinꢀtheꢀsurfaceꢀareaꢀ
2 3
O
ꢀphaseꢀorꢀtoꢀm‐ZrO ꢀcanꢀbeꢀ
2
butꢀ toꢀ aꢀ decreaseꢀ inꢀ theꢀ poreꢀ volumeꢀ andꢀ aꢀ decreaseꢀ inꢀ theꢀ
amountꢀofꢀmesopores.ꢀTheꢀincreaseꢀinꢀmesoporesꢀwithꢀtheꢀin‐
creaseꢀofꢀNt/mꢀfromꢀ0.15ꢀtoꢀ0.18ꢀcanꢀenhanceꢀtheꢀdiffusionꢀofꢀtheꢀ
formedꢀ mainꢀ productꢀ α‐(2,5‐dimethylphenyl)‐styrene.ꢀ Asꢀ aꢀ
result,ꢀ theꢀ amountꢀ ofꢀ thermodynamicallyꢀ stableꢀ sideꢀ productꢀ
β‐(2,5‐dimethylphenyl)‐styreneꢀformedꢀbyꢀisomerizationꢀofꢀtheꢀ
mainꢀproductꢀdecreasesꢀowingꢀtoꢀtheꢀdecreasedꢀstayingꢀtimeꢀasꢀ
aꢀresultꢀofꢀquickꢀdiffusion.ꢀTheꢀdecreasedꢀamountꢀofꢀmesoporesꢀ
andꢀporeꢀvolumeꢀbyꢀtheꢀfurtherꢀincreaseꢀofꢀNt/mꢀfromꢀ0.18ꢀtoꢀ
2
ꢀ
2
TheꢀincreaseꢀinꢀCTABꢀconcentrationꢀresultsꢀinꢀaꢀdecreaseꢀinꢀtheꢀ
averageꢀ crystalliteꢀ sizeꢀ (CSZr)ꢀ shownꢀ inꢀ Tableꢀ 2ꢀ owingꢀ toꢀ theꢀ
inhibitingꢀ effectꢀ ofꢀ surfaceꢀ micellesꢀ onꢀ theꢀ agglomerationꢀ ofꢀ
2−ꢀ andꢀ ZrO
2
ZrO ꢀ particlesꢀ [40].ꢀ Theꢀ interactionꢀ betweenꢀ SO
4
2
ꢀ
wouldꢀbeꢀstrengthenedꢀasꢀtheꢀaverageꢀcrystalliteꢀsizeꢀdecreas‐
es.ꢀ Asꢀ aꢀ result,ꢀ theꢀ peakꢀ towardsꢀ theꢀ superꢀ acidꢀ centeredꢀ atꢀ
2−/meso‐La0.1Zr0.9
aboveꢀ600ꢀ°CꢀcanꢀbeꢀseenꢀonꢀtheꢀSO
4
δ
O ꢀsolidꢀ
4
3
3
2
2
1
1
00
50
00
50
00
50
00
8
1
84
7
6
(
a)
80
378
(b)
231
60
0
0
0
0
.04
40
20
0
.03
.02
.01
549
N =0.15 N =0.18 N =0.20
t/m
t/m
t/m
N =0.15
t/m
t/m
N =0.15
N =0.18
t/m
t/m
N =0.18
0.00
N =0.20
Nt/m=0.20
0
5 1015202530
Pore diameter (nm)
t/m
5
0
0
0.0
0.2
0.4
Relative pressure (p/p0)
ꢀadsorption‐desorptionꢀisothermsꢀ(a)ꢀandꢀNH
t/mꢀvalues.ꢀInsetsꢀinꢀFig.ꢀ1(a)ꢀareꢀtheꢀspecificꢀsurfaceꢀareaꢀandꢀBJHꢀporeꢀdiameterꢀdistributionꢀfromꢀtheꢀdesorptionꢀbranch.ꢀ
0.6
0.8
1.0
100
200
300
400
500
600
700
o
Temperature ( C)
Fig.ꢀ1.ꢀN
N
2
3
‐TPDꢀprofilesꢀ(b)ꢀofꢀtheꢀas‐preparedꢀSO 2
4
−/meso‐La0.1Zr0.9
O
δ
ꢀsolidꢀacidꢀcatalystsꢀwithꢀvarious

ꢀ
ZhongkuiꢀZhaoꢀetꢀal.ꢀ/ꢀChineseꢀJournalꢀofꢀCatalysisꢀ37ꢀ(2016)ꢀ1303–1313ꢀ
Tableꢀ3ꢀ
1307ꢀ

Effectꢀ ofꢀ theꢀ
N
a/m
ꢀ
δ
valueꢀ onꢀ theꢀ catalyticꢀ performanceꢀ ofꢀ
ꢀ solidꢀ acidꢀ catalystsꢀ forꢀ theꢀ alkenylationꢀ ofꢀ
2−
tetragonal
SO
4
/meso‐La0.1Zr0.9
O

p‐xyleneꢀwithꢀphenylacetylene.ꢀ
Con.ꢀ
Productionꢀdistributionꢀ(%)ꢀ

Na/mꢀ
(
%)ꢀ
Iꢀ
IIꢀ
IIIꢀ
4.0ꢀ
2.5ꢀ
3.0ꢀ
3.9ꢀ
IVꢀ
0.1ꢀ
0.2ꢀ
0.2ꢀ
0.1ꢀ
Vꢀ


14ꢀ
83.7ꢀ
91.8ꢀ
91.6ꢀ
84.4ꢀ
92.1ꢀ
93.9ꢀ
93.7ꢀ
93.3ꢀ
0.3ꢀ
0.3ꢀ
0.1ꢀ
0.2ꢀ
3.5ꢀ
3.2ꢀ
3.0ꢀ
2.5ꢀ
1
1
2
6ꢀ
8ꢀ
0ꢀ

(3)
(
2)
1)
r
Reactionꢀconditions:ꢀcatalystꢀ1.0ꢀg,ꢀnAr/nPhenꢀ=ꢀ25,ꢀT ꢀ=ꢀ150ꢀ°C,ꢀP ꢀ=ꢀ1.0ꢀ
s
MPa,ꢀVHSVꢀ=ꢀ6ꢀmL/(gcat·h),ꢀTOSꢀ=ꢀ8ꢀh.ꢀ
ꢀ
(
2
0
30
40
50
60
70
80
theꢀconversionꢀincreasesꢀwithꢀtheꢀincreaseꢀofꢀNa/mꢀfromꢀ14ꢀtoꢀ
6.ꢀNoꢀvisibleꢀchangeꢀtakesꢀplaceꢀasꢀNa/mꢀisꢀincreasedꢀfromꢀ16ꢀ
toꢀ18.ꢀHowever,ꢀfurtherꢀincreaseꢀofꢀNa/mꢀfromꢀ18ꢀtoꢀ20ꢀleadsꢀtoꢀ
anꢀ obviousꢀ decreaseꢀ inꢀ catalyticꢀ activity.ꢀ Theꢀ oppositeꢀ odderꢀ
towardsꢀ isomersꢀ canꢀ beꢀ observed.ꢀ Moreover,ꢀ aꢀ monotonousꢀ
decreaseꢀinꢀoligomerꢀpercentageꢀwithꢀtheꢀincreaseꢀofꢀNa/mꢀfromꢀ
o
2
/( )
1
Fig.ꢀ2.ꢀXRDꢀpatternsꢀofꢀtheꢀSO
withꢀvariousꢀNt/mꢀvalues.ꢀ(1)ꢀNt/mꢀ=ꢀ0.15;ꢀ(2)ꢀNt/mꢀ=ꢀ0.18;ꢀ(3)ꢀNt/mꢀ=ꢀ0.20.
4
2−/meso‐La0.1Zr0.9
O
2
ꢀsolidꢀacidꢀcatalysts
acidsꢀwithꢀ0.18ꢀandꢀ0.20ꢀofꢀNt/m,ꢀbutꢀaꢀvisibleꢀpeakꢀcanꢀbeꢀseenꢀ
2−/meso‐La0.1Zr0.9
2−/meso‐La0.1Zr0.9
14ꢀtoꢀ20ꢀcanꢀbeꢀseen.ꢀFromꢀtheꢀresults,ꢀtheꢀ16ꢀofꢀN
ꢀphysisorption,ꢀNH ‐TPD,ꢀandꢀXRDꢀwereꢀemployedꢀtoꢀin‐
vestigateꢀtheꢀ structure‐performanceꢀ relationshipsꢀofꢀtheꢀ cata‐
lysts.ꢀN ꢀadsorption‐desorptionꢀisothermsꢀandꢀtheꢀcorrespond‐
ingꢀBJHꢀporeꢀsizeꢀdistributionsꢀusingꢀtheꢀdesorptionꢀbranchꢀofꢀ
theꢀ isotherm,ꢀ asꢀ wellꢀ asꢀ NH ‐TPDꢀ profilesꢀ ofꢀ
SO ꢀwithꢀvariousꢀNa/mꢀvaluesꢀareꢀshownꢀinꢀ
Fig.ꢀ3.ꢀTheꢀtypeꢀIVꢀisothermsꢀwithꢀaꢀhysteresisꢀloopꢀatꢀaꢀhighꢀ
relativeꢀ pressureꢀ indicatesꢀ thatꢀ theꢀ SO
solidꢀacidꢀcatalystsꢀbelongꢀtoꢀtheꢀmesoporousꢀmaterialꢀfamilyꢀ
[41].ꢀFromꢀFig.ꢀ3(a)ꢀandꢀTableꢀ4,ꢀtheꢀincreaseꢀinꢀtheꢀNa/mꢀvalueꢀ
fromꢀ 14ꢀ toꢀ 16ꢀ leadsꢀ toꢀ anꢀ increaseꢀ inꢀ poreꢀ volumeꢀ andꢀ theꢀ
amountꢀ ofꢀ largerꢀ mesopores,ꢀ butꢀ itꢀ doesꢀ notꢀ resultꢀ inꢀ anꢀ in‐
creaseꢀinꢀsurfaceꢀarea.ꢀFromꢀtheꢀaverageꢀcrystalliteꢀsizeꢀlistedꢀinꢀ
a/mꢀisꢀoptimal.ꢀ
towardsꢀ superꢀ acidꢀ onꢀ theꢀ SO
withꢀ 0.15ꢀ ofꢀ Nt/m.ꢀ Theꢀ SO
.18ꢀofꢀNt/mꢀhasꢀsimilarꢀstrongꢀacidicꢀsitesꢀtoꢀthatꢀwithꢀ0.15ꢀofꢀ
t/m,ꢀ butꢀ theꢀ formerꢀ hasꢀ superꢀ acidicꢀ sites.ꢀ Asꢀ aꢀ result,ꢀ moreꢀ
oligomersꢀ wereꢀ observedꢀ onꢀ theꢀ formerꢀ (Tableꢀ 1).ꢀ Althoughꢀ
thereꢀ areꢀ moreꢀ superꢀ acidicꢀ sitesꢀ onꢀ SO
4
O
δ
ꢀ solidꢀ acidꢀ
N
2
3
4
O
δ
ꢀ solidꢀacidꢀwithꢀ
0
N
2
2−/meso‐La0.1Zr0.9
3
4
δ
O ꢀ
2−/meso‐La0.1Zr0.9
O
δ
solidꢀacidꢀwithꢀofꢀ0.20ꢀNt/mꢀthanꢀtheꢀoneꢀwithꢀ0.18ꢀofꢀNt/m,ꢀmuchꢀ
lessꢀ strongꢀ acidicꢀ sitesꢀ canꢀ beꢀ observedꢀ onꢀ theꢀ former.ꢀ Asꢀ
shownꢀinꢀTableꢀ1,ꢀlessꢀoligomersꢀwereꢀobservedꢀonꢀtheꢀformer.ꢀ
Correlatingꢀ theꢀ oligomerizationꢀ resultsꢀ toꢀ acidicꢀ properties,ꢀ itꢀ
canꢀbeꢀproposedꢀthatꢀtheꢀstrongꢀandꢀsuperꢀacidicꢀsitesꢀareꢀtheꢀ
mainꢀactiveꢀsitesꢀforꢀoligomerization.ꢀ
Fromꢀtheꢀaboveꢀanalysis,ꢀitꢀcanꢀbeꢀconcludedꢀthatꢀtheꢀcata‐
lyticꢀperformanceꢀincludingꢀactivityꢀandꢀproductꢀdistributionꢀisꢀ
significantlyꢀ dependentꢀ onꢀ theꢀ acidicꢀ propertiesꢀ andꢀ poreꢀ
structureꢀofꢀtheꢀsolidꢀacidꢀcatalysts.ꢀTheꢀacidicꢀpropertiesꢀareꢀ
affectedꢀ byꢀ texturalꢀ featuresꢀ andꢀ crystalꢀ phaseꢀ ofꢀ theꢀ me‐
4
2−/meso‐La0.1Zr0.9
O ꢀ
4
δ
Tableꢀ4,ꢀtheꢀincreasedꢀNa/mꢀvalueꢀcanꢀleadꢀtoꢀlargerꢀZrO
tals.ꢀ Theꢀ increasedꢀ poreꢀ volumeꢀ andꢀ amountꢀ ofꢀ largerꢀ meso‐
poresꢀ ofꢀ theꢀ SO ꢀ preparedꢀ withꢀ theꢀ 16ꢀ ofꢀ
Na/mꢀallowꢀitꢀtoꢀhaveꢀmoreꢀweakꢀandꢀmediumꢀacidicꢀsitesꢀthanꢀ
2
ꢀcrys‐
2−/meso‐La0.1Zr0.9
O
4
δ
so‐La0.1Zr0.9
O
δ
ꢀ compositeꢀ oxides.ꢀ Theꢀ Nt/mꢀ valueꢀ hasꢀ anꢀ influ‐
enceꢀonꢀtheꢀtexturalꢀnature,ꢀacidicꢀsites,ꢀandꢀcrystallineꢀphaseꢀofꢀ
theꢀcatalyst.ꢀTheꢀincreaseꢀinꢀweakꢀandꢀmediumꢀacidicꢀsitesꢀisꢀofꢀ
benefitꢀ forꢀ theꢀ alkenylationꢀ reaction,ꢀ butꢀ strongꢀ andꢀ superꢀ
acidicꢀsitesꢀwouldꢀleadꢀtoꢀoligomerizationꢀandꢀdeepꢀpolymeri‐
zation.ꢀ Therefore,ꢀ theꢀ 0.18ꢀ ofꢀ Nt/mꢀ isꢀ idealꢀ forꢀ obtainingꢀ solidꢀ
acidꢀcatalystsꢀwithꢀexcellentꢀalkenylationꢀproperties.ꢀ
thoseꢀwithꢀ14ꢀofꢀNa/m,ꢀwhichꢀfavorsꢀtheꢀalkenylationꢀreaction.ꢀ
Theꢀ increasedꢀ poreꢀ volumeꢀ andꢀ amountꢀ ofꢀ largerꢀ mesoporesꢀ
alsoꢀstrengthensꢀtheꢀdiffusionꢀofꢀtheꢀmainꢀproduct,ꢀwhichꢀsup‐
pressesꢀtheꢀformationꢀofꢀtheꢀisomers.ꢀFromꢀtheꢀresultsꢀinꢀsec‐
tionꢀ3.1,ꢀtheꢀoligomerꢀpercentageꢀisꢀstronglyꢀdependentꢀonꢀtheꢀ
strongꢀandꢀsuperꢀacidicꢀsites.ꢀHerein,ꢀtheꢀsolidꢀacidꢀwithꢀ16ꢀofꢀ
Na/mꢀproducesꢀlessꢀoligomersꢀthanꢀtheꢀoneꢀwithꢀ14ꢀofꢀNa/m,ꢀalt‐
3
.2.ꢀ ꢀ Effectꢀofꢀmolarꢀratioꢀofꢀammoniaꢀtoꢀmetalꢀionsꢀ
houghꢀtheꢀformerꢀhasꢀmoreꢀstrongꢀandꢀsuperꢀacidicꢀsites.ꢀThisꢀ
mayꢀ beꢀascribedꢀtoꢀtheꢀexistenceꢀofꢀlargerꢀmesoporesꢀonꢀtheꢀ
former.ꢀTheꢀfurtherꢀincreaseꢀofꢀtheꢀNa/mꢀfromꢀ16ꢀtoꢀ20ꢀleadsꢀtoꢀaꢀ
decreaseꢀinꢀtheꢀsurfaceꢀareaꢀandꢀporeꢀvolume.ꢀThisꢀleadsꢀtoꢀaꢀ
decreaseꢀinꢀweakꢀandꢀmediumꢀacidicꢀsites,ꢀwhichꢀsubsequentlyꢀ
resultsꢀ inꢀ theꢀ loweringꢀ ofꢀ theꢀ catalyticꢀ activityꢀ (Tableꢀ 3).ꢀ Alt‐
houghꢀtheꢀpeakꢀcenteredꢀatꢀ549ꢀ°Cꢀforꢀtheꢀsolidꢀacidꢀwithꢀ20ꢀofꢀ
Theꢀ ammoniaꢀ concentrationꢀ wouldꢀ affectꢀ theꢀ formationꢀ ofꢀ
surfactantꢀ micelles,ꢀ theꢀ nucleationꢀ andꢀ growthꢀ ofꢀ Zr(OH) ,ꢀ asꢀ
4
wellꢀasꢀtheꢀassemblyꢀprocessꢀforꢀmesoporousꢀZr–Oꢀsolꢀandꢀgel.ꢀ
Asꢀaꢀconsequence,ꢀtheꢀtuningꢀofꢀtheꢀNa/mꢀvaluesꢀbyꢀ fixingꢀtheꢀ
otherꢀparametersꢀ(Nt/mꢀ=ꢀ0.18,ꢀThydroꢀ=ꢀ105ꢀ°C,ꢀandꢀthydroꢀ=ꢀ60ꢀh)ꢀ
mayꢀ efficientlyꢀ regulateꢀ theꢀ texturalꢀ featuresꢀ andꢀ theꢀ ZrO
crystalꢀofꢀtheꢀmeso‐La0.1Zr0.9 ꢀcompositeꢀoxides,ꢀwhichꢀinꢀturnꢀ
affectsꢀtheꢀcatalyticꢀperformance.ꢀTheꢀcatalyticꢀperformanceꢀofꢀ
theꢀ SO ꢀ solidꢀ acidsꢀ preparedꢀ withꢀ variousꢀ
a/mꢀvaluesꢀforꢀtheꢀalkenylationꢀofꢀp‐xyleneꢀwithꢀphenylacety‐
leneꢀwasꢀinvestigated.ꢀFromꢀtheꢀresultsꢀpresentedꢀinꢀTableꢀ3,ꢀ
2
ꢀ
N
a/mꢀisꢀslightlyꢀhigherꢀthanꢀthatꢀofꢀtheꢀoneꢀwithꢀ16ꢀofꢀNa/m,ꢀtheꢀ
formerꢀhasꢀaꢀlowerꢀnumberꢀofꢀstrongꢀacidicꢀsites.ꢀMoreover,ꢀtheꢀ
largerꢀcrystalliteꢀsizeꢀofꢀZrO ꢀforꢀtheꢀsolidꢀacidꢀwithꢀ20ꢀofꢀNa/mꢀisꢀ
higherꢀthanꢀthatꢀforꢀtheꢀsolidꢀacidꢀwithꢀ16ꢀofꢀNa/m.ꢀTheꢀlargerꢀ
ZrO ꢀcrystalꢀsizeꢀofꢀtheꢀsampleꢀwithꢀ20ꢀofꢀNa/mꢀsuppressesꢀtheꢀ
interactionꢀofꢀSO .ꢀAsꢀaꢀresult,ꢀnoꢀsuperꢀacidicꢀsitesꢀ
2−ꢀandꢀZrO
O
δ
2
2−/meso‐La0.1Zr0.9
4
O
δ
N
2
4
2

1308ꢀ
ZhongkuiꢀZhaoꢀetꢀal.ꢀ/ꢀChineseꢀJournalꢀofꢀCatalysisꢀ37ꢀ(2016)ꢀ1303–1313ꢀ
4
3
3
2
2
1
1
00
50
00
50
00
50
00
3
78
8
5
85
(a)
(b)
8
6
4
2
0
0
0
0
0
70
231
0.04
0.03
0.02
0.01
0.00
549
Na/m=14 Na/m=16 Na/m=20
Na/m=14
Na/m=16
N
N
N
a/m=14
a/m=16
a/m=20
Na/m=20
0
5 1015202530
Pore diameter (nm)
5
0
0
0.0
0.2
0.4
Relative pressure (p/p0)
ꢀadsorption‐desorptionꢀisothermsꢀ(a)ꢀandꢀNH
0.6
0.8
1.0
100
200
300
Temperature ( C)
ꢀsolidꢀacidꢀcatalystsꢀwithꢀvariousꢀ
400
500
600
700
o
Fig.ꢀ3.ꢀN
2
3
‐TPDꢀprofilesꢀ(b)ꢀofꢀtheꢀas‐preparedꢀSO 2
4
−/meso‐La0.1Zr0.9
O
δ
molarꢀratiosꢀofꢀammoniaꢀtoꢀmetalꢀ(Na/m).ꢀInsetsꢀinꢀFig.ꢀ3(a)ꢀareꢀtheꢀspecificꢀsurfaceꢀareaꢀandꢀBJHꢀporeꢀdiameterꢀdistributionꢀfromꢀtheꢀdesorptionꢀ
branch.ꢀ
onꢀthisꢀ sampleꢀ canꢀ beꢀobserved.ꢀTheꢀlowerꢀamountꢀofꢀstrongꢀ
acidicꢀsitesꢀandꢀtheꢀabsenceꢀofꢀsuperꢀacidicꢀsitesꢀresultsꢀinꢀlessꢀ
oligomers.ꢀ Furthermore,ꢀ theꢀ decreaseꢀ inꢀ mesoporesꢀ ofꢀ theꢀ
sampleꢀwithꢀ20ꢀofꢀNa/mꢀinꢀcomparisonꢀwithꢀtheꢀoneꢀwithꢀ16ꢀofꢀ
inꢀtheꢀwholeꢀinvestigatedꢀrange.ꢀ
FromꢀFig.ꢀ4ꢀandꢀTableꢀ6,ꢀanꢀincreaseꢀinꢀtheꢀsurfaceꢀareaꢀfromꢀ
2
57ꢀtoꢀ79ꢀm /gꢀandꢀanꢀenlargedꢀporeꢀvolumeꢀfromꢀ0.28ꢀtoꢀ0.37ꢀ
3
cm /gꢀ canꢀ beꢀ obtainedꢀ asꢀ Thydroꢀ increasesꢀ fromꢀ 75ꢀ toꢀ 90ꢀ °C,ꢀ
N
a/mꢀ leadsꢀ toꢀ worseꢀ diffusionꢀ ofꢀ theꢀ formedꢀ mainꢀ product,ꢀ
whichꢀleadsꢀtoꢀanꢀincreaseꢀinꢀacidicꢀsites.ꢀItꢀisꢀestimatedꢀbyꢀtheꢀ
Scherrerꢀ equationꢀ basedꢀ onꢀ XRDꢀ patternsꢀ thatꢀ theꢀ averageꢀ
crystalꢀ sizeꢀ decreasesꢀ fromꢀ 6.9ꢀ toꢀ 5.5ꢀ nmꢀ asꢀ Thydroꢀ increasesꢀ
whichꢀ isꢀ ofꢀ benefitꢀ forꢀ theꢀ formationꢀ ofꢀ thermodynamicallyꢀ
stableꢀisomers.ꢀAsꢀaꢀresult,ꢀaꢀhigherꢀisomerꢀpercentageꢀcanꢀbeꢀ
observedꢀforꢀtheꢀcatalystꢀpreparedꢀusingꢀ20ꢀofꢀNa/mꢀcomparedꢀ
withꢀ 16ꢀ ofꢀ Na/m,ꢀ asꢀ shownꢀ inꢀ Tableꢀ 3.ꢀ Theꢀ presenceꢀ ofꢀ moreꢀ
weakꢀandꢀmediumꢀacidicꢀsites,ꢀlargerꢀporeꢀvolume,ꢀandꢀlargerꢀ
mesoporesꢀmakeꢀtheꢀsolidꢀacidꢀcatalystꢀexhibitꢀexcellentꢀcata‐
lyticꢀperformance.ꢀBasedꢀonꢀtheꢀestablishedꢀtemplateꢀandꢀam‐
moniaꢀ dosage,ꢀ theꢀ effectꢀ ofꢀ theꢀ hydrothermalꢀ conditionsꢀ in‐
cludingꢀtheꢀThydroꢀandꢀthydroꢀonꢀtheꢀnatureꢀofꢀtheꢀcatalystꢀandꢀitsꢀ
catalyticꢀperformanceꢀinꢀtheꢀalkenylationꢀreactionꢀwasꢀinvesti‐
gated.ꢀ ꢀ
fromꢀ75ꢀtoꢀ90ꢀ°C.ꢀTheꢀsmallerꢀZrO
strongerꢀinteractionꢀbetweenꢀtheꢀSO
2
ꢀcrystalliteꢀsizeꢀmayꢀallowꢀ
2−ꢀandꢀZr,ꢀwhichꢀleadsꢀtoꢀ
4
theꢀformationꢀofꢀsuperꢀacidicꢀsites.ꢀBesidesꢀtheꢀimprovedꢀacces‐
sibilityꢀofꢀtheꢀacidicꢀsitesꢀbyꢀtheꢀincreasedꢀsurfaceꢀareaꢀandꢀporeꢀ
volume,ꢀtheꢀincreaseꢀinꢀacidicꢀsitesꢀisꢀofꢀbenefitꢀforꢀtheꢀalkenyl‐
ationꢀreaction.ꢀAsꢀaꢀresult,ꢀtheꢀsolidꢀacidꢀwithꢀtheꢀ90ꢀ°CꢀofꢀThydro
ꢀ
exhibitsꢀhigherꢀactivity,ꢀasꢀshownꢀinꢀTableꢀ5.ꢀTheꢀsuperꢀacidicꢀ
sitesꢀonꢀtheꢀcatalystꢀwithꢀtheꢀ90ꢀ°CꢀofꢀThydroꢀpromoteꢀoligomeri‐
zation,ꢀleadingꢀtoꢀtheꢀformationꢀofꢀmoreꢀoligomers.ꢀTheꢀsolidꢀ
acidꢀwithꢀtheꢀ90ꢀ°CꢀofꢀThydroꢀhasꢀaꢀlargerꢀporeꢀvolumeꢀthanꢀtheꢀ
oneꢀwithꢀtheꢀ75ꢀ°CꢀofꢀThydro,ꢀwhichꢀisꢀofꢀbenefitꢀforꢀtheꢀdiffusionꢀ
ofꢀ theꢀ formedꢀ α‐arylstyrene.ꢀ Thisꢀ reducesꢀ theꢀ chanceꢀ ofꢀ itsꢀ
isomerization.ꢀ Asꢀ aꢀ result,ꢀ aꢀ decreasedꢀ amountꢀ ofꢀ theꢀ
3.3.ꢀ ꢀ Effectꢀofꢀhydrothermalꢀtemperatureꢀ
Tableꢀ5ꢀpresentsꢀtheꢀeffectꢀofꢀThydroꢀonꢀtheꢀcatalyticꢀperfor‐
manceꢀofꢀtheꢀas‐synthesizedꢀsolidꢀacidꢀcatalystsꢀinꢀtheꢀalkenyla‐
tionꢀofꢀp‐xyleneꢀwithꢀphenylacetyleneꢀbyꢀfixingꢀtheꢀotherꢀcondi‐
tionsꢀincludingꢀtheꢀ0.18ꢀofꢀNt/m,ꢀ16ꢀofꢀNa/m,ꢀandꢀ60ꢀhꢀofꢀthydro.ꢀAsꢀ
shownꢀinꢀTableꢀ5,ꢀtheꢀconversionꢀincreasesꢀwithꢀtheꢀincreaseꢀofꢀ
β‐arylstyreneꢀisomerꢀcanꢀbeꢀobtained.ꢀFurtherꢀincreaseꢀofꢀThydroꢀ
upꢀtoꢀ120ꢀ°Cꢀleadsꢀtoꢀaꢀdecreaseꢀinꢀsurfaceꢀareaꢀandꢀporeꢀvol‐
ume,ꢀwhichꢀresultsꢀinꢀaꢀdecreaseꢀinꢀtheꢀactiveꢀsites,ꢀtheꢀweakꢀ
andꢀmediumꢀacidicꢀsites,ꢀforꢀalkenylation.ꢀAsꢀaꢀconsequence,ꢀtheꢀ
conversionꢀdecreasesꢀfromꢀ91.8%ꢀtoꢀ84.1%,ꢀasꢀshownꢀinꢀTableꢀ
Thydroꢀupꢀtoꢀ90ꢀ°C,ꢀatꢀwhichꢀtheꢀconversionꢀreachesꢀaꢀmaximumꢀ
93.5%).ꢀFurtherꢀincreaseꢀofꢀThydroꢀleadsꢀtoꢀaꢀdecreaseꢀinꢀcon‐
(
5.ꢀ Moreover,ꢀ theꢀ furtherꢀ decreasedꢀ ZrO ꢀ crystalꢀ sizeꢀ leadsꢀ toꢀ
2
version.ꢀAꢀlowerꢀisomerꢀpercentageꢀcanꢀbeꢀobservedꢀasꢀThydroꢀisꢀ
increasedꢀfromꢀ75ꢀtoꢀ105ꢀ°C,ꢀhoweverꢀtheꢀisomerꢀpercentageꢀ
risesꢀasꢀThydroꢀisꢀfurtherꢀincreasedꢀtoꢀ120ꢀ°C.ꢀMoreover,ꢀtheꢀoli‐
gomerꢀpercentageꢀmonotonouslyꢀrisesꢀasꢀtheꢀThydroꢀisꢀincreasedꢀ
moreꢀsuperꢀacidicꢀsites,ꢀasꢀshownꢀinꢀFig.ꢀ4(b).ꢀItꢀwasꢀalsoꢀob‐
Tableꢀ5ꢀ
Effectꢀ ofꢀ theꢀ
T
hydro
ꢀ
δ
valueꢀ onꢀ theꢀ catalyticꢀ performanceꢀ ofꢀ
ꢀ solidꢀ acidꢀ catalystsꢀ forꢀ theꢀ alkenylationꢀ ofꢀ
p‐xyleneꢀwithꢀphenylacetylene.ꢀ
2−
SO
4
/meso‐La0.1Zr0.9
O
Tableꢀ4ꢀ
T
(°C)ꢀ
hydroꢀ
Conv.ꢀ
(%)ꢀ
Productꢀdistributionꢀ(%)ꢀ
Effectꢀ ofꢀ Na/mꢀ valueꢀ onꢀ theꢀ CSZrꢀ andꢀ Vtotalꢀ ofꢀ theꢀ as‐synthesizedꢀ
2−/meso‐La0.1Zr0.9
Iꢀ
IIꢀ
IIIꢀ
5.0ꢀ
IVꢀ
0.1ꢀ
Vꢀ
SO
4
2
O ꢀsolidꢀacidꢀcatalyst.ꢀ
7
9
1
5ꢀ
0ꢀ
05ꢀ
80.2ꢀ
93.5ꢀ
91.8ꢀ
84.1ꢀ
92.5ꢀ
93.8ꢀ
93.9ꢀ
93.1ꢀ
0.1ꢀ
0.3ꢀ
0.3ꢀ
0.4ꢀ
2.2ꢀ
2.4ꢀ
3.2ꢀ
3.5ꢀ
N
a/m
ꢀ
CSZrꢀaꢀ(nm)ꢀ
5.3ꢀ
V
totalꢀ ꢀ(cm /g)ꢀ
0.36ꢀ
b
3
3.4ꢀ
0.1ꢀ
1
4ꢀ
6ꢀ
0ꢀ
2.5ꢀ
0.2ꢀ
1
5.5ꢀ
6.0ꢀ
0.41ꢀ
0.35ꢀ
2
120ꢀ
3.7ꢀ
0.2ꢀ
aꢀ
bꢀ
Estimatedꢀ byꢀ Scherrerꢀ equationꢀ fromꢀ XRDꢀ patterns;ꢀ Fromꢀ N
sisorption.ꢀ
2
ꢀ phy‐
Reactionꢀconditions:ꢀcatalystꢀ1.0ꢀg,ꢀnAr/
n
Phenꢀ=ꢀ25,ꢀT
r
ꢀ=ꢀ150ꢀ°C,ꢀP ꢀ=ꢀ1.0ꢀ
s
MPa,ꢀVHSVꢀ=ꢀ6ꢀmL/(gcat·h),ꢀTOSꢀ=ꢀ8ꢀh.ꢀ

ꢀ
ZhongkuiꢀZhaoꢀetꢀal.ꢀ/ꢀChineseꢀJournalꢀofꢀCatalysisꢀ37ꢀ(2016)ꢀ1303–1313ꢀ
1309ꢀ
4
3
3
2
2
1
1
00
50
00
50
00
50
00
7
9
8
6
4
2
0
0
0
0
0
408
(
a)
(b)
6
4
231
57
0
0
0
.03
.02
.01
549
3
78
o
o
o
Thydro=75 C T =90 C T =120 C
hydro
hydro
o
Thydro=75 C
o
o
Thydro=90 C
Thydro=75 C
0.00
o
o
0
5 1015202530
Pore diameter (nm)
Thydro=120 C
Thydro=90 C
5
0
o
Thydro=120 C
0
0
.0
0.2
0.4
0.6
0.8
1.0
100
200
300
400
500
600
700
o
Relative pressure (p/p0)
Temperature ( C)
Fig.ꢀ4.ꢀN
2
ꢀadsorption‐desorptionꢀisothermsꢀ(a)ꢀandꢀNH
3
‐TPDꢀprofilesꢀ(b)ꢀofꢀtheꢀas‐preparedꢀSO 2
4
−/meso‐La0.1Zr0.9
O ꢀsolidꢀacidꢀcatalystsꢀatꢀvariousꢀ
δ
hydrothermalꢀtemperaturesꢀ(Thydro).ꢀInsetsꢀinꢀFig.ꢀ4(a)ꢀareꢀtheꢀspecificꢀsurfaceꢀareaꢀandꢀBJHꢀporeꢀdiameterꢀdistributionꢀfromꢀtheꢀdesorptionꢀbranch.ꢀ
servedꢀthatꢀtheꢀm‐ZrO
2
ꢀphaseꢀexistsꢀinꢀtheꢀsolidꢀacidꢀwithꢀtheꢀ
Tableꢀ7,ꢀandꢀtheꢀpercentageꢀofꢀoligomersꢀincreasesꢀslightly.ꢀTheꢀ
increasedꢀ thydroꢀ leadsꢀ toꢀ aꢀ relativelyꢀ smallerꢀ ZrO ꢀ crystalꢀ size,ꢀ
whichꢀ possessꢀ superꢀ acidicꢀ sitesꢀ owingꢀ toꢀ aꢀ strengthenedꢀ in‐
teractionꢀbetweenꢀSO .ꢀTheꢀfurtherꢀincreaseꢀofꢀthydro
2−ꢀandꢀZrO
120ꢀ°CꢀofꢀThydroꢀ[37–39],ꢀwhichꢀmightꢀaffectꢀtheꢀacidicꢀproper‐
2
ties.ꢀTheꢀformationꢀofꢀmoreꢀstrongꢀandꢀsuperꢀacidicꢀsitesꢀwouldꢀ
promoteꢀtheꢀformationꢀofꢀmoreꢀoligomers.ꢀTheꢀdecreaseꢀinꢀtheꢀ
4
2
ꢀ
amountꢀ ofꢀ largerꢀ mesoporesꢀ onꢀ theꢀ SO
4
2−/meso‐La0.1Zr0.9
O
δ
ꢀ
fromꢀ60ꢀtoꢀ84ꢀhꢀleadsꢀtoꢀaꢀdecreaseꢀinꢀtheꢀsurfaceꢀarea,ꢀresultingꢀ
inꢀ aꢀ decreaseꢀ inꢀ weak,ꢀ medium,ꢀ andꢀ strongꢀ acidicꢀ sites.ꢀ Asꢀ aꢀ
result,ꢀaꢀmuchꢀlowerꢀconversionꢀwithꢀslightlyꢀlowerꢀoligomersꢀ
canꢀ beꢀ observed.ꢀ Furthermore,ꢀ theꢀ poreꢀ volumeꢀ andꢀ theꢀ
amountꢀofꢀlargerꢀmesoporesꢀmonotonouslyꢀrisesꢀasꢀtheꢀthydroꢀisꢀ
extended,ꢀwhichꢀresultsꢀinꢀtheꢀmonotonousꢀdecreaseꢀinꢀisomersꢀ
owingꢀ toꢀ theꢀ suppressionꢀ ofꢀ theꢀ isomerizationꢀ ofꢀ theꢀ formedꢀ
α‐arylstyrene.ꢀ ꢀ
preparedꢀwithꢀtheꢀ120ꢀ°CꢀofꢀThydroꢀinꢀcomparisonꢀwithꢀtheꢀoneꢀ
withꢀtheꢀ90ꢀ °Cꢀ ofꢀThydroꢀleadsꢀ toꢀaꢀ decreaseꢀinꢀtheꢀ amountꢀofꢀ
isomers.ꢀTheꢀsolidꢀacidꢀpreparedꢀwithꢀtheꢀ75ꢀ°CꢀofꢀThydroꢀpro‐
ducesꢀ theꢀ mostꢀ isomersꢀ amongꢀ theꢀ threeꢀ samples,ꢀ whichꢀ isꢀ
ascribedꢀtoꢀtheꢀsmallestꢀporeꢀvolumeꢀandꢀlowestꢀsurfaceꢀarea.ꢀ ꢀ
3.4.ꢀ ꢀ Effectꢀofꢀhydrothermalꢀtimeꢀ
Fromꢀ above,ꢀ itꢀ canꢀ beꢀ concludedꢀ thatꢀ theꢀ
Herein,ꢀtheꢀeffectꢀofꢀthydroꢀvalueꢀ(thydroꢀ=ꢀ36,ꢀ60,ꢀandꢀ84ꢀh)ꢀonꢀ
SO
4
2−/meso‐La0.1Zr0.9
δ
O ꢀ withꢀ appropriateꢀ preparationꢀ condi‐
theꢀnatureꢀofꢀtheꢀcatalystꢀandꢀtheꢀcatalyticꢀperformanceꢀinꢀtheꢀ
alkenylationꢀwasꢀfurtherꢀinvestigatedꢀbyꢀfixingꢀtheꢀotherꢀcondi‐
tionsꢀincludingꢀtheꢀ0.18ꢀofꢀNt/m,ꢀ16ꢀofꢀNa/m,ꢀandꢀ90ꢀ°CꢀofꢀThydro.ꢀ
Fromꢀ Tableꢀ 7,ꢀ theꢀ phenylacetyleneꢀ conversionꢀ increasesꢀ withꢀ
theꢀincreaseꢀofꢀthydro,ꢀandꢀasꢀthydroꢀreachesꢀ60ꢀh,ꢀtheꢀconversionꢀ
reachesꢀaꢀmaximumꢀ(93.5%).ꢀFurtherꢀincreaseꢀofꢀthydroꢀleadsꢀtoꢀ
aꢀdecreaseꢀinꢀconversion.ꢀMoreover,ꢀfromꢀtheꢀproductꢀdistribu‐
tion,ꢀtheꢀextendedꢀhydrothermalꢀtimeꢀleadsꢀtoꢀaꢀdecreaseꢀinꢀtheꢀ
tionsꢀforꢀmeso‐La0.1Zr0.9
O
δ
ꢀcompositeꢀoxidesꢀexhibitedꢀexcellentꢀ
catalyticꢀperformanceꢀinꢀtheꢀalkenylationꢀreaction.ꢀCorrelatingꢀ
ofꢀtheꢀreactionꢀresultsꢀtoꢀtheꢀnatureꢀofꢀtheꢀcatalyst,ꢀweꢀfoundꢀ
thatꢀtheꢀcatalyticꢀactivityꢀandꢀproductꢀdistributionꢀareꢀstronglyꢀ
dependentꢀ onꢀ theꢀ acidicꢀ propertiesꢀ andꢀ theꢀ accessibilityꢀ ofꢀ
acidicꢀ sites,ꢀ whichꢀ dependꢀ onꢀ theꢀ preparationꢀ conditionsꢀ ofꢀ
meso‐La0.1Zr0.9
O
δ
ꢀ
compositeꢀ oxides.ꢀ Theꢀ developedꢀ
ꢀwithꢀtheꢀ0.18ꢀofꢀNt/m,ꢀ16ꢀofꢀNa/m,ꢀ90ꢀ°Cꢀ
SO
4
2−/meso‐La0.1Zr0.9
O
δ
percentageꢀofꢀisomers,ꢀbutꢀtheꢀsolidꢀacidꢀwithꢀtheꢀ60ꢀhꢀofꢀthydro
hasꢀslightlyꢀhigherꢀformationꢀofꢀoligomers.ꢀVariousꢀcharacteri‐
zationꢀ experimentsꢀ wereꢀ performedꢀ toꢀ exploreꢀ theꢀ struc‐
ture‐performanceꢀrelationship.ꢀ
ꢀ
ofꢀThydro,ꢀandꢀ60ꢀhꢀofꢀthydroꢀexhibitsꢀgreatꢀpotentialꢀforꢀproduc‐
tionꢀofꢀα‐arylstyreneꢀthroughꢀFriedel‐Craftsꢀalkenylation.ꢀ ꢀ
3.5.ꢀ ꢀ Catalyticꢀstabilityꢀ
FromꢀFig.ꢀ5ꢀandꢀTableꢀ8,ꢀtheꢀincreaseꢀofꢀthydroꢀfromꢀ36ꢀtoꢀ60ꢀhꢀ
leadsꢀ toꢀ anꢀ increaseꢀ inꢀ theꢀ surfaceꢀ area,ꢀ poreꢀ volume,ꢀ theꢀ
amountꢀofꢀweakꢀandꢀmediumꢀacidicꢀsites,ꢀandꢀtheꢀamountꢀofꢀtheꢀ
largerꢀmesopores,ꢀwhichꢀenhancesꢀtheꢀalkenylationꢀreaction.ꢀAsꢀ
aꢀ result,ꢀ thereꢀ isꢀ anꢀ increaseꢀ inꢀ theꢀ conversion,ꢀ asꢀ shownꢀ inꢀ
Theꢀcatalyticꢀstabilityꢀandꢀtheꢀscopeꢀofꢀtheꢀsubstratesꢀoverꢀ
theꢀdevelopedꢀsolidꢀacidꢀcatalystꢀwereꢀinvestigated.ꢀTheꢀcata‐
Tableꢀ7ꢀ
Effectꢀ ofꢀ theꢀ
t
hydro
ꢀ
valueꢀ onꢀ theꢀ catalyticꢀ performanceꢀ ofꢀ
2−
SO
4
/meso‐La0.1Zr0.9
O
δ
ꢀ solidꢀ acidꢀ catalystsꢀ forꢀ theꢀ alkenylationꢀ ofꢀ
Tableꢀ6ꢀ
p‐xyleneꢀwithꢀphenylacetylene.ꢀ
Effectꢀ ofꢀ Thydroꢀ valueꢀ onꢀ theꢀ CSZrꢀ andꢀ Vtotalꢀ ofꢀ theꢀ as‐synthesizedꢀ
2−/meso‐La0.1Zr0.9
Conv.ꢀ
Productꢀdistributionꢀ(%)ꢀ
SO
4
2
O ꢀsolidꢀacidꢀcatalyst.ꢀ
T
hydroꢀ(h)
(
%)ꢀ
Iꢀ
IIꢀ
IIIꢀ
3.9ꢀ
3.4ꢀ
3.2ꢀ
IVꢀ
Vꢀ
T
7
9
hydroꢀ(°C)ꢀ
5ꢀ
0ꢀ
CSZrꢀaꢀ(nm)ꢀ
6.9ꢀ
V
totalꢀ ꢀ(cm /g)ꢀ
0.28ꢀ
b
3
3
6ꢀ
84.1ꢀ
93.5ꢀ
86.9ꢀ
93.4
93.8
94.3
0.4ꢀ
0.3ꢀ
0.3ꢀ
0.1ꢀ
0.1ꢀ
0.1ꢀ
2.2ꢀ
2.4ꢀ
2.2ꢀ
5.5ꢀ
0.37ꢀ
60ꢀ
84ꢀ
1
20ꢀ
5.2ꢀ
0.30ꢀ
aꢀ
Estimatedꢀ byꢀ Scherrerꢀ equationꢀ fromꢀ XRDꢀ patterns;ꢀ bꢀ Fromꢀ
Reactionꢀconditions:ꢀcatalystꢀ 1.0ꢀ g,ꢀ nAr/nPhenꢀ=ꢀ 25,ꢀ Trꢀ=ꢀ 150ꢀ °C,ꢀ Psꢀ=ꢀ1.0ꢀ
2
N physisorption.ꢀ
MPa,ꢀVHSVꢀ=ꢀ6ꢀmL/(gcat·h),ꢀTOSꢀ=ꢀ8ꢀh.ꢀ

1310ꢀ
ZhongkuiꢀZhaoꢀetꢀal.ꢀ/ꢀChineseꢀJournalꢀofꢀCatalysisꢀ37ꢀ(2016)ꢀ1303–1313ꢀ
4
3
3
2
2
1
1
00
50
00
50
00
50
00
7
9
8
6
4
2
0
0
0
0
0
75
(
a)
408
67
(b)
242
0
0
0
.03
.02
.01
546
thydro=36 h thydro=60 h thydro=84 h
thydro=36 h
thydro=60 h
thydro=84 h
thydro=36 h
thydro=60 h
thydro=84 h
0.00
0
5 10 15 20 25 30
Pore diameter (nm)
5
0
0
0
.0
0.2
0.4
0.6
0.8
1.0
100
200
300
400
500
600
700
o
Relative pressure (p/p0)
Temperature ( C)
Fig.ꢀ5.ꢀN
2
ꢀadsorption‐desorptionꢀisothermsꢀ(a)ꢀandꢀNH
3
‐TPDꢀprofilesꢀ(b)ꢀofꢀtheꢀas‐preparedꢀSO 2
4
−/meso‐La0.1Zr0.9
O ꢀsolidꢀacidꢀcatalystsꢀwithꢀvariousꢀ
δ
hydrothermalꢀtimesꢀ(thydro).ꢀInsetsꢀinꢀFig.ꢀ5aꢀareꢀtheꢀspecificꢀsurfaceꢀareaꢀandꢀBJHꢀporeꢀdiameterꢀdistributionꢀfromꢀtheꢀdesorptionꢀbranch.ꢀ
Tableꢀ8ꢀ
SummaryꢀofꢀtheꢀalkenylationꢀofꢀdifferentꢀaromaticsꢀwithꢀphenylacetyleneꢀoverꢀtheꢀdevelopedꢀSO
4
2−/meso‐La0.1Zr0.9
δ
O ꢀsolidꢀacidꢀcatalyst.ꢀ
Con.ꢀ
%)ꢀ
Sel.ꢀ Yieldꢀa
Con.ꢀ
(%)ꢀ
Sel.ꢀ
(%)ꢀ
Yieldꢀaꢀ
(%)ꢀ
Entryꢀ Substrateꢀ
Productꢀ
Entry
7ꢀ
Substrateꢀ
Productꢀ
(
(%)ꢀ
(%)
S
1ꢀ
91.7ꢀ
62.6ꢀ 57.4
93.8ꢀ 87.7
92.9ꢀ
94.8ꢀ
97.1ꢀ
76.6ꢀ
71.2ꢀ
90.2ꢀ
88.4ꢀ
S
ꢀ
ꢀ
O
ꢀ
c
O
2ꢀ
93.5ꢀ
8 ꢀ
95.1ꢀ
91.0ꢀ
ꢀ
3ꢀ
99.0ꢀ
98.6ꢀ
97.6ꢀ 96.6
91.0ꢀ 89.7
9ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
4ꢀ
O
O
ꢀ
ꢀ
10ꢀ
96.9ꢀ
98.6ꢀ
97.9ꢀ
85.2ꢀ
94.9ꢀ
84.0ꢀ
OH
ꢀ
ꢀ
5ꢀb
ꢀ
ꢀ
95.4ꢀ
86.5ꢀ
77.6ꢀ 74.0
72.5ꢀ 62.7
OH
ꢀ
ꢀ
6ꢀb
11ꢀ
ꢀ
ꢀ
aꢀ
bꢀ
Reactionꢀconditions:ꢀcatalystꢀ1.0ꢀg,ꢀnAr/
n
Phenꢀ=ꢀ25,ꢀTrꢀ=ꢀ150ꢀ°C,ꢀPsꢀ=ꢀ1.0ꢀMPa,ꢀVHSVꢀ=ꢀ6ꢀmL/(gcat·h);ꢀ GCꢀyield;ꢀ Theꢀcyclohexaneꢀorꢀdioxaneꢀwasꢀintro‐
ducedꢀintoꢀtheꢀfeedꢀforꢀeasyꢀmaterialꢀtransferꢀinꢀtheꢀfixed‐bedꢀreactor.
lyticꢀstabilityꢀplaysꢀanꢀimportantꢀroleꢀinꢀpracticalꢀapplicationꢀofꢀ
aꢀ solidꢀ acidꢀ catalyst.ꢀ Therefore,ꢀ theꢀ stabilityꢀ ofꢀ theꢀ developedꢀ
gestsꢀaꢀhigherꢀcoke‐resistantꢀstabilityꢀofꢀtheꢀoptimizedꢀcatalyst.ꢀ
Therefore,ꢀ theꢀ developedꢀ SO ꢀ preparedꢀ
2−/meso‐La0.1Zr0.9
O
4
δ
SO
4
2−/meso‐La0.1Zr0.9
O
2
ꢀsolidꢀacidꢀinꢀtheꢀalkenylationꢀreactionꢀ
underꢀappropriateꢀconditionsꢀcouldꢀbeꢀaꢀpromisingꢀsolidꢀacidꢀ
catalystꢀforꢀtheꢀalkenylationꢀreaction.ꢀ ꢀ
ofꢀp‐xyleneꢀwithꢀphenylacetyleneꢀwasꢀinvestigated.ꢀFig.ꢀ6ꢀpre‐
sentsꢀ theꢀ conversionꢀ andꢀ selectivityꢀ asꢀ aꢀ functionꢀ ofꢀ timeꢀ onꢀ
streamꢀforꢀtheꢀalkenylationꢀoverꢀtheꢀoptimizedꢀsolidꢀacidꢀcata‐
lyst;ꢀ theꢀ unoptimizedꢀ catalystꢀ (previouslyꢀ developedꢀ
Py‐IRꢀisꢀaꢀpowerfulꢀtoolꢀforꢀinvestigatingꢀtheꢀacidicꢀproper‐
tiesꢀ ofꢀ theꢀ catalysts.ꢀ Theꢀ Py‐IRꢀ spectraꢀ ofꢀ theꢀ optimizedꢀ solidꢀ
catalystꢀinꢀthisꢀworkꢀandꢀtheꢀunoptimizedꢀsolidꢀacidꢀcatalystsꢀatꢀ
150,ꢀ300,ꢀandꢀ450ꢀ°Cꢀofꢀdesorptionꢀtemperature,ꢀcorrespondingꢀ
toꢀtotalꢀacidicꢀsites,ꢀmediumꢀplusꢀstrongꢀacidicꢀsites,ꢀandꢀstrongꢀ
acidicꢀsites,ꢀrespectively,ꢀwereꢀcollectedꢀandꢀareꢀpresentedꢀinꢀ
Fig.ꢀ7.ꢀTheꢀoptimizedꢀsolidꢀacidꢀhasꢀmoreꢀacidicꢀsites,ꢀincludingꢀ
BꢀandꢀLꢀacids,ꢀinꢀcomparisonꢀwithꢀtheꢀunoptimizedꢀone.ꢀMoreꢀ
interestingly,ꢀtheꢀremarkableꢀincreaseꢀinꢀLꢀacidicꢀsitesꢀoverꢀtheꢀ
optimizedꢀsolidꢀacidꢀcatalystꢀcanꢀbeꢀseenꢀinꢀcomparisonꢀwithꢀ
SO
4
2−/meso‐La0.1Zr0.9
O
2
ꢀsolidꢀacidꢀ[16])ꢀisꢀincludedꢀforꢀcompar‐
ison.ꢀFromꢀFig.ꢀ6,ꢀtheꢀoptimizedꢀSO
4
2−/meso‐La0.1Zr0.9
δ
O ꢀinꢀthisꢀ
workꢀ exhibitsꢀ muchꢀ higherꢀ stabilityꢀ inꢀ comparisonꢀ withꢀ theꢀ
unoptimizedꢀ one,ꢀ andꢀ moreꢀ thanꢀ 62.5%ꢀ conversionꢀ canꢀ beꢀ
maintainedꢀ forꢀ upꢀ toꢀ 31ꢀ hꢀ ofꢀ timeꢀ onꢀ streamꢀ comparedꢀ withꢀ
onlyꢀ45.4%ꢀconversionꢀobtainedꢀforꢀtheꢀunoptimizedꢀcatalyst.ꢀ
FromꢀTGAꢀexperiments,ꢀtheꢀ15.1%ꢀandꢀ25.6%ꢀofꢀmassꢀlossꢀforꢀ
theꢀ optimizedꢀ andꢀ unoptimizedꢀ solidꢀ acids,ꢀ respectively,ꢀ sug‐
theꢀincreaseꢀinꢀBꢀacidicꢀsites.ꢀTheꢀinteractionꢀofꢀSO
4
2−ꢀandꢀZrO
ꢀ
2

ꢀ
ZhongkuiꢀZhaoꢀetꢀal.ꢀ/ꢀChineseꢀJournalꢀofꢀCatalysisꢀ37ꢀ(2016)ꢀ1303–1313ꢀ
1311ꢀ
3.6.ꢀ ꢀ Scopeꢀofꢀsubstratesꢀ
100
Herein,ꢀtheꢀscopeꢀofꢀtheꢀsubstratesꢀforꢀtheꢀalkenylationꢀoverꢀ
theꢀ developedꢀ SO ꢀ catalystꢀ wasꢀ investigat‐
8
6
4
2
0
0
0
0
0
2−/meso‐La0.1Zr0.9
O
4
δ
ed,ꢀandꢀtheꢀreactionꢀresultsꢀareꢀlistedꢀinꢀTableꢀ5.ꢀTheꢀdevelopedꢀ
solidꢀ acidꢀ catalystꢀ demonstratesꢀ excellentꢀ catalyticꢀ perfor‐
manceꢀwithꢀmoreꢀthanꢀ90%ꢀconversionꢀandꢀhighꢀselectivityꢀforꢀ
theꢀalkenylationꢀofꢀdiverseꢀaromatics,ꢀsuggestingꢀaꢀbroadꢀscopeꢀ
ofꢀaromaticsꢀforꢀtheꢀalkenylationꢀforꢀtheꢀproductionꢀofꢀdifferentꢀ
α‐arylstyrenes.ꢀ Togetherꢀ withꢀ theꢀ facileꢀ regenerationꢀ ofꢀ theꢀ
usedꢀsolidꢀacidꢀcatalystꢀestablishedꢀinꢀourꢀpreviousꢀpaperꢀ[16],ꢀ
Conversion (Optimized)
Selectivity (Optimized)
Conversion (Unoptimized)
Selectivity (Unoptimized)
theꢀdevelopedꢀSO
4
2−/meso‐La0.1Zr0.9
O ꢀcouldꢀbeꢀconsideredꢀasꢀaꢀ
δ
potentialꢀcandidateꢀforꢀcleanꢀandꢀatomꢀefficientꢀproductionꢀofꢀ
diverseꢀ α‐arylstyrenesꢀ andꢀ industriallyꢀ importantꢀ intermedi‐
atesꢀ throughꢀ theꢀ Friedel‐Craftsꢀ alkenylationꢀ ofꢀ differentꢀ aro‐
maticsꢀwithꢀphenylacetylene.ꢀ ꢀ
5
10
15
Time on stream (h)
Fig.ꢀ6.ꢀTheꢀcatalyticꢀstabilityꢀofꢀtheꢀdevelopedꢀSO
catalystꢀforꢀtheꢀalkenylationꢀofꢀp‐xyleneꢀwithꢀphenylacetylene.ꢀReaction
conditions:ꢀcatalystꢀ1.0ꢀg,ꢀnAr/ Phenꢀ=ꢀ25,ꢀTrꢀ=ꢀ150ꢀ°C,ꢀPsꢀ=ꢀ1.0ꢀMPa,ꢀVHSVꢀ=ꢀ
ꢀmL/(gcat·h).ꢀ
20
25
30
2−/meso‐La0.1Zr0.9
O
δ
4
n
4.ꢀ ꢀ Conclusionsꢀ
6
Theꢀtexturalꢀfeaturesꢀandꢀacidicꢀpropertiesꢀofꢀsulfatedꢀmes‐
leadsꢀtoꢀtheꢀproductionꢀofꢀLꢀacidꢀsites,ꢀandꢀsubsequentlyꢀtheꢀBꢀ
acidicꢀsitesꢀcanꢀbeꢀformedꢀbyꢀtheꢀincorporationꢀofꢀH OꢀinꢀtheꢀLꢀ
oporousꢀlanthana‐zirconiaꢀsolidꢀacidꢀcatalystsꢀwereꢀefficientlyꢀ
tunedꢀ byꢀ adjustingꢀ theꢀ preparationꢀ conditions,ꢀ includingꢀ theꢀ
molarꢀratioꢀofꢀtheꢀtemplateꢀtoꢀmetalꢀions,ꢀmolarꢀratioꢀofꢀammo‐
niaꢀ toꢀ metalꢀ ions,ꢀ hydrothermalꢀ temperature,ꢀ andꢀ hydrother‐
malꢀtime,ꢀwhichꢀsignificantlyꢀaffectedꢀtheꢀacidicꢀsitesꢀandꢀtheirꢀ
accessibility.ꢀ Asꢀ aꢀ consequence,ꢀ theꢀ conversionꢀ andꢀ productꢀ
distributionꢀcouldꢀbeꢀregulated.ꢀTheꢀoptimizedꢀsulfatedꢀmeso‐
porousꢀ lanthana‐zirconiaꢀ solidꢀ acidꢀ catalystsꢀ demonstratedꢀ
muchꢀsuperiorꢀcatalyticꢀactivityꢀandꢀstabilityꢀandꢀsimilarꢀselec‐
tivityꢀtowardsꢀα‐arylstyreneꢀtoꢀtheꢀunoptimizedꢀone.ꢀCombingꢀ
theꢀexcellentꢀcatalyticꢀactivity,ꢀselectivity,ꢀandꢀstability,ꢀasꢀwellꢀ
asꢀtheꢀbroadꢀscopeꢀofꢀsubstratesꢀandꢀeasyꢀregenerationꢀofꢀtheꢀ
usedꢀ catalyst,ꢀ theꢀ developedꢀ sulfatedꢀ mesoporousꢀ lantha‐
na‐zirconiaꢀ solidꢀ acidꢀ catalystsꢀ couldꢀ haveꢀ greatꢀ potentialꢀ forꢀ
industrialꢀproductionꢀofꢀα‐arylstyreneꢀthroughꢀcleanꢀandꢀatomꢀ
efficientꢀ solid‐acid‐mediatedꢀ Friedel‐Craftsꢀ alkenylationꢀ ofꢀ di‐
verseꢀaromaticsꢀwithꢀphenylacetylene.ꢀ
2
acidꢀsites.ꢀFromꢀreferencesꢀ[13–16],ꢀbothꢀBꢀandꢀLꢀacidicꢀsitesꢀ
canꢀenhanceꢀtheꢀalkenylationꢀreaction,ꢀandꢀtherefore,ꢀtheꢀsolidꢀ
acidꢀ catalystꢀ developedꢀ inꢀ thisꢀ workꢀ exhibitsꢀ aꢀ muchꢀ higherꢀ
catalyticꢀactivityꢀforꢀalkenylationꢀinꢀcomparisonꢀwithꢀtheꢀunop‐
timizedꢀone.ꢀMoreover,ꢀtheꢀstrongꢀBꢀacidicꢀsitesꢀmayꢀenhanceꢀ
theꢀ polymerizationꢀ sideꢀ reactions.ꢀ Theꢀ notablyꢀ increasedꢀ
amountꢀofꢀtotalꢀacidicꢀsitesꢀonꢀtheꢀoptimizedꢀcatalystꢀdramati‐
callyꢀincreasesꢀtheꢀconversionꢀofꢀphenylacetyleneꢀinꢀtheꢀmainꢀ
reaction,ꢀ whichꢀ decreasesꢀ theꢀ concentrationꢀ ofꢀ phenylacety‐
lene.ꢀThisꢀmayꢀweakenꢀtheꢀpolymerizationꢀandꢀtheꢀsubsequentꢀ
cokeꢀ depositionꢀ onꢀ theꢀ optimizedꢀ catalyst.ꢀ Furthermore,ꢀ weꢀ
investigatedꢀS‐leachingꢀinꢀtheꢀreactionꢀprocessꢀbyꢀXPSꢀanalysisꢀ
(
Sꢀ2p)ꢀofꢀtheꢀfreshꢀandꢀspentꢀSO
4
2−/meso‐La0.1Zr0.9
O .ꢀTheꢀXPSꢀ
δ
resultsꢀdemonstrateꢀthatꢀtheꢀsurfaceꢀatomicꢀratioꢀofꢀSꢀtoꢀZrꢀde‐
creasesꢀfromꢀ0.24ꢀtoꢀ0.20ꢀafterꢀtheꢀcatalystꢀisꢀusedꢀinꢀtheꢀaboveꢀ
reactionꢀprocess,ꢀimplyingꢀthatꢀS‐leachingꢀisꢀanotherꢀreasonꢀforꢀ
theꢀdecreaseꢀinꢀconversion.ꢀMoreꢀstableꢀsolidꢀcatalystsꢀwillꢀbeꢀ
exploredꢀinꢀtheꢀfuture.ꢀ
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1312ꢀ
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GraphicalꢀAbstractꢀ
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ZhongkuiꢀZhao*,ꢀJinfengꢀRan,ꢀYongleꢀGuo,ꢀBoyuanꢀMiao,ꢀGuiruꢀWangꢀ
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