Phakathi kwee-oxides ezingezizo i-siliceous, i-alumina ineempawu ezilungileyo zoomatshini, ukuxhathisa ubushushu obuphezulu kunye nokuxhathisa ukubola, ngelixa i-mesoporous alumina (MA) inobungakanani bepore ehlengahlengiswayo, indawo enkulu yendawo ethile, umthamo omkhulu wepore kunye neendleko eziphantsi zokuvelisa, ezisetyenziswa ngokubanzi kwi-catalysis, ukukhutshwa kweziyobisi ezilawulwayo, i-adsorption kunye nezinye iindawo, ezifana nokuqhekeka, i-hydrocracking kunye ne-hydrodesulfurization ye-petroleum eluhlaza.Ngokomzekelo, kwinkqubo yokucocwa kokuphuma kwemoto, ukungcola okufakwe kwi-injini yezongezo ze-oyile kuya kwenza i-coke, eya kukhokelela ekuvalelekeni kwee-catalyst pores, ngoko ukunciphisa umsebenzi we-catalyst.I-surfactant ingasetyenziselwa ukulungelelanisa isakhiwo se-alumina carrier ukwenza i-MA.Ukuphucula ukusebenza kwayo kwe-catalytic.
I-MA inempembelelo yokunyanzeliswa, kwaye iintsimbi ezisebenzayo zivaliwe emva kokubalwa kobushushu obuphezulu.Ukongezelela, emva kokubalwa kobushushu obuphezulu, isakhiwo se-mesoporous siyawa, i-MA skeleton ikwimeko ye-amorphous, kwaye i-acidity yomhlaba ayikwazi ukuhlangabezana neemfuno zayo kwintsimi yokusebenza.Unyango lokuguqulwa luhlala lufuneka ekuphuculeni umsebenzi we-catalytic, i-mesoporous structure stability, i-surface stability ye-thermal kunye ne-acidity ebusweni bezinto ze-MA.Amaqela okuguqulwa okuqhelekileyo aquka i-heteroatoms yensimbi (Fe, Co, Ni, Cu, Zn, Pd, Pt, Zr, njl. ) kunye nee-oxide zetsimbi (TiO2, NiO, Co3O4, CuO, Cu2O, RE2O7, njl.)Ilayishwe kumphezulu we-MA okanye ifakwe kwi-skeleton.
Ubume be-electron obukhethekileyo bezinto ezinqabileyo zomhlaba zenza ukuba iikhompawundi zayo zibe neempawu ezikhethekileyo ze-optical, umbane kunye nemagnethi, kwaye isetyenziswe kwizixhobo ze-catalytic, izinto ze-photoelectric, i-adsorption materials kunye ne-magnetic materials.Umhlaba onqabileyo oguqulwe izinto ze-mesoporous unokulungelelanisa ipropati ye-asidi (alkali), ukwandisa isithuba se-oksijini, kunye nokudibanisa isinyithi se-nanocrystalline catalyst kunye nokusabalalisa okufanayo kunye nesikali se-nanometer esizinzileyo. Izinto ezifanelekileyo ezixhamlayo kunye nemihlaba enqabileyo inokuphucula ukusasazwa komphezulu we-nanocrystals zetsimbi kunye nokuzinza kunye nokubekwa kwekhabhoni ukuxhathisa kwe-catalysts.Kulo phepha, ukuguqulwa komhlaba onqabileyo kunye nokusebenza kwe-MA kuya kuqaliswa ukuphucula ukusebenza kwe-catalytic, ukuzinza kwe-thermal, umthamo wokugcina i-oksijeni, indawo ethile yendawo kunye nesakhiwo se-pore.
Ukulungiselela i-1 MA
1.1 ukulungiswa kwe-alumina carrier
Indlela yokulungiselela i-alumina carrier imisela ukuhanjiswa kwesakhiwo sayo se-pore, kunye neendlela zayo zokulungiselela eziqhelekileyo ziquka i-pseudo-boehmite (PB) indlela yokuphelelwa ngamanzi kunye nendlela ye-sol-gel.I-Pseudoboehmite (PB) yaqala yacetywa nguCalvet, kwaye i-H + yakhuthaza i-peptization ukuze ifumane i-γ-AlOOH i-colloidal PB equkethe amanzi e-interlayer, efakwe i-calcined kunye ne-dehydrated kwiqondo lokushisa eliphezulu ukwenza i-alumina.Ngokwezinto ezihlukeneyo eziluhlaza, zihlala zihlulwe ngendlela yemvula, indlela ye-carbonization kunye ne-alcoholluminium hydrolysis method.I-colloidal solubility ye-PB ichaphazeleka yi-crystallinity, kwaye iphuculwe ngokunyuka kwe-crystallinity, kwaye iphinda ichaphazeleke kwiiparameters zenkqubo yokusebenza.
I-PB idla ngokulungiswa ngendlela yemvula.Ialkali yongezwa kwisisombululo se-aluminate okanye i-asidi yongezwa kwisisombululo se-alumina kunye ne-precipitated ukufumana i-alumina e-hydrated (i-alkali precipitation), okanye i-asidi yongezwa kwi-aluminate precipitation ukuze ifumane i-alumina monohydrate, ethi emva koko ihlanjwe, yomiswe kwaye ifakwe i-calcined ukufumana i-PB.Indlela ye-precipitation ilula ukusebenza kwaye iphantsi kweendleko, ehlala isetyenziswa kwimveliso yemizi-mveliso, kodwa iphenjelelwa yizinto ezininzi (isisombululo pH, ukugxininiswa, ubushushu, njl.) Kwaye loo meko yokufumana i-particle kunye ne-dispersibility engcono ingqongqo.Kwindlela ye-carbonization, i-Al (OH) i-3 ifunyenwe ngokuphendula kwe-CO2 kunye ne-NaAlO2, kunye ne-PB inokufumaneka emva kokuguga.Le ndlela ineenzuzo zokusebenza okulula, umgangatho ophezulu wemveliso, akukho ngcoliseko kunye neendleko eziphantsi, kwaye inokulungiselela i-alumina kunye nomsebenzi ophezulu we-catalytic, ukuxhatshazwa kwe-corrosion egqwesileyo kunye nommandla ophezulu ophezulu kunye notyalo-mali oluphantsi kunye nokubuyisela okuphezulu. ukulungiselela ucoceko oluphezulu lwePB.I-aluminiyam alkoxide i-hydrolyzed ukwenza i-aluminium oxide monohydrate, kwaye emva koko iphathwe ukuze ifumane i-PB ecocekileyo, ene-crystallinity enhle, ubungakanani besuntswana elifanayo, ukusabalalisa ubungakanani bepore kunye nokunyaniseka okuphezulu kwamasuntswana angqukuva.Nangona kunjalo, le nkqubo intsonkothile, kwaye kunzima ukuchacha ngenxa yokusetyenziswa kwezinyibilikisi ezithile eziyityhefu.
Ukongeza, iityuwa ezingaphiliyo okanye iikhompawundi eziphilayo zesinyithi ziqhele ukusetyenziselwa ukulungiselela precursors alumina ngendlela sol-gel, kunye namanzi acocekileyo okanye izinyibilikisi eziphilayo zongezwa ukulungiselela izisombululo ukuvelisa sol, nto leyo ke gelled, yomisiwe kwaye yosiwe.Okwangoku, inkqubo yokulungiselela i-alumina isaphuculwa ngesiseko se-PB dehydration method, kwaye indlela ye-carbonization iye yaba yindlela ephambili yokuvelisa i-alumina ye-industrial ngenxa yoqoqosho kunye nokukhusela okusingqongileyo.I-Alumina elungiselelwe yindlela ye-sol-gel iye yatsala ingqalelo enkulu ngenxa yobukhulu obufanayo bosasazo lwepore, eyindlela enokwenzeka, kodwa kufuneka iphuculwe ukuze kuphunyezwe ukusetyenziswa kwemizi-mveliso.
1.2 Ukulungiselela i-MA
I-alumina eqhelekileyo ayikwazi ukuhlangabezana neemfuno zokusebenza, ngoko ke kuyimfuneko ukulungiselela ukusebenza okuphezulu kwe-MA.Iindlela zokudibanisa ngokuqhelekileyo ziquka: indlela ye-nano-casting kunye ne-carbon mold njenge-template enzima;I-Synthesis ye-SDA: Inkqubo yokuzihlanganisa eyenziwe ngu-Evaporation-induced self-assembly (EISA) phambi kweetemplate ezithambileyo ezifana ne-SDA kunye nezinye i-cationic, i-anionic okanye i-nonionic surfactants.
1.2.1 Inkqubo ye-EISA
Ithemplate ethambileyo isetyenziswe kwimeko ye-acidic, ethintela inkqubo enzima kunye nexesha elide lendlela ye-membrane enzima kwaye inokuqonda ukumodareyitha okuqhubekayo kwe-aperture.Ukulungiswa kwe-MA yi-EISA kutsale ingqalelo enkulu ngenxa yokufumaneka kwayo ngokulula kunye nokuphinda kuphinde kuphinde kuphinde kuphinde kuphinde kuphindekezwe.Izakhiwo ezahlukeneyo ze-mesoporous zinokulungiswa.Ubungakanani bepore ye-MA bunokutshintshwa ngokuguqula ubude be-hydrophobic chain of surfactant okanye ukulungelelanisa umlinganiselo we-molar we-hydrolysis catalyst ukuya kwi-aluminium precursor kwisisombululo.Ngoko ke, i-EISA, eyaziwa ngokuba yinyathelo elinye kunye nokuguqulwa kwendlela ye-sol-gel yendawo ephezulu. indawo MA kunye wayalela mesoporous alumina (OMA), sele isetyenziswe ezahlukeneyo templates ethambileyo, ezifana P123, F127, triethanolamine (tea), njl. , ngokuqhelekileyo i-aluminiyam isopropoxide kunye ne-P123, yokubonelela ngemathiriyeli ye-mesoporous.Uphuhliso oluyimpumelelo lwenkqubo ye-EISA lufuna uhlengahlengiso oluchanekileyo lwe-hydrolysis kunye ne-condensation kinetics ukufumana i-sol ezinzileyo kunye nokuvumela ukuphuhliswa kwe-mesophase eyenziwe yi-surfactant micelles kwi-sol.
Kwinkqubo ye-EISA, ukusetyenziswa kwezinyibiliki ezingenamanzi (ezifana ne-ethanol) kunye ne-organic complexing agents zinokucotha ngokufanelekileyo i-hydrolysis kunye ne-condensation rate ye-organoaluminium precursors kwaye ibangele ukuhlanganiswa kwezinto ze-OMA, ezifana ne-Al (OR) 3and. i-aluminiyam isopropoxide.Nangona kunjalo, kwizinyibilikisi ezingaguquguqukiyo ezingenamanzi, iitemplates ze-surfactant zihlala ziphulukana ne-hydrophilicity yazo / i-hydrophobicity.Ukongeza, ngenxa yokulibaziseka kwe-hydrolysis kunye ne-polycondensation, imveliso ephakathi ineqela le-hydrophobic, eyenza kube nzima ukusebenzisana netemplate ye-surfactant.Kuphela xa ukuxinwa kwe-surfactant kunye neqondo le-hydrolysis kunye ne-polycondensation ye-aluminiyam yanda ngokuthe ngcembe kwinkqubo yokunyuka kwe-solvent evaporation inokuthi i-self-assembly ye-template kunye ne-aluminium yenzeke.Ke ngoko, iiparitha ezininzi ezichaphazela iimeko zomphunga we-solvents kunye ne-hydrolysis kunye ne-condensation reaction of precursors, Njengobushushu, ukufuma okuhambelanayo, i-catalyst, ireyithi yokunyuka kwe-solvent, njl., iya kuchaphazela ubume bokugqibela bendibano.Njengoko kubonisiwe kwifig.I-1, izixhobo ze-OMA ezinozinzo oluphezulu lwe-thermal kunye nokusebenza okuphezulu kwe-catalytic zaye zadityaniswa yi-solvothermal encediswa yi-evaporation induced self-assembly (SA-EISA).unyango lwe-solvothermal lukhuthaze i-hydrolysis epheleleyo ye-aluminium precursors ukwenza amaqela amancinci e-aluminium hydroxyl yeqoqo elincinci, eliphucule intsebenziswano phakathi kwe-surfactants kunye ne-aluminiyam.I-mesophase ene-dimensional emibini ye-hexagonal yaqulunqwa kwinkqubo ye-EISA kwaye yafakwa kwi-400℃ ukwenza imathiriyeli ye-OMA.Kwinkqubo ye-EISA yendabuko, inkqubo yokukhupha i-evaporation ihamba kunye ne-hydrolysis ye-organoaluminium precursor, ngoko ke iimeko zokufudumala zinempembelelo ebalulekileyo ekuphenduleni kunye nesakhiwo sokugqibela se-OMA.Inyathelo lonyango lwe-solvothermal likhuthaza i-hydrolysis epheleleyo ye-aluminium precursor kwaye ivelise inxalenye edibeneyo ye-aluminium edibeneyo ye-aluminiyam.Xa kuthelekiswa ne-MA elungiselelwe ngokwesiko le-EISA indlela, i-OMA elungiselelwe yindlela ye-SA-EISA inomthamo ophezulu wepore, indawo ethile engcono kunye nokuzinza okungcono kwe-thermal.Kwixesha elizayo, indlela ye-EISA ingasetyenziselwa ukulungisa i-ultra-enkulu yokuvula i-MA enezinga eliphezulu lokuguqulwa kunye nokukhetha okugqwesileyo ngaphandle kokusebenzisa i-arhente yokubuyisela kwakhona.
Isazobe soku-1 sokuhamba kwetshati yendlela ye-SA-EISA yokudibanisa imathiriyeli ye-OMA
1.2.2 ezinye iinkqubo
Ukulungiswa kwe-MA okuqhelekileyo kufuna ulawulo oluchanekileyo lweeparamitha ze-synthesis ukufezekisa isakhiwo esicacileyo se-mesoporous, kunye nokususwa kwezinto ze-template nazo zingumngeni, onzima inkqubo yokudibanisa.Okwangoku, iincwadi ezininzi ziye zaxela ukuhlanganiswa kwe-MA ngeetemplates ezahlukeneyo.Kwiminyaka yakutshanje, uphando lugxininise kakhulu kwi-synthesis ye-MA kunye ne-glucose, i-sucrose kunye nesitashi njengeetemplates nge-aluminium isopropoxide kwisisombululo esimanzi.Ininzi yalezi zixhobo ze-MA zenziwe nge-aluminium nitrate, i-sulfate kunye ne-alkoxide njengemithombo ye-aluminium.I-MA CTAB nayo ifunyenwe ngokuguqulwa ngokuthe ngqo kwe-PB njengomthombo we-aluminium.I-MA eneempawu ezahlukeneyo zesakhiwo, oko kukuthi i-Al2O3) -1, i-Al2O3) -2 kunye ne-al2o3Kwaye inozinzo oluhle lwe-thermal.Ukongezwa kwe-surfactant akutshintshi ubume bekristale be-PB, kodwa kutshintsha indlela yokupakisha yamasuntswana.Ukongezelela, ukubunjwa kwe-Al2O3-3 yenziwe ngokunamathela kwe-nanoparticles ezinziswe yi-PEG ye-solvent ye-organic okanye i-aggregation ejikeleze i-PEG.Nangona kunjalo, ubungakanani bobungakanani bepore ye-Al2O3-1 buncinci kakhulu.Ukongezelela, ii-catalysts ezisekelwe kwi-palladium zilungiselelwe nge-MA yokwenziwa njenge-carrier.In methane ukutsha kwe-reaction reaction, i-catalyst exhaswa yi-Al2O3-3 ibonise ukusebenza kakuhle kwe-catalytic.
Okokuqala, i-MA enobungakanani obumxinwa kakhulu bokuhanjiswa kwepore yalungiswa ngokusebenzisa ixabiso eliphantsi kunye ne-aluminiyam ecebileyo ye-aluminium emnyama ye-slag ABD.Inkqubo yokuvelisa ibandakanya inkqubo yokukhutshwa kwiqondo lokushisa eliphantsi kunye noxinzelelo oluqhelekileyo.Amasuntswana aqinileyo ashiywe kwinkqubo yokukhutshwa awayi kungcolisa imo engqongileyo, kwaye anokufunjwa ngomngcipheko ophantsi okanye aphinde asetyenziswe njengokuzalisa okanye ukuhlanganisana kwisicelo sekhonkrithi.Indawo ethile yommandla we-MA edibeneyo yi-123 ~ 162m2 / g, Ukuhanjiswa kobungakanani bepore kuncinci, i-radius ephezulu yi-5.3nm, kunye ne-porosity yi-0.37 cm3 / g.Izinto eziphathekayo zi-nano-size kwaye ubukhulu bekristale bu malunga ne-11nm.I-Solid-state synthesis yinkqubo entsha yokwenza i-MA, enokuthi isetyenziswe ukuvelisa i-radiochemical absorbent ukuze isetyenziswe ekliniki.I-aluminium chloride, i-ammonium carbonate kunye ne-glucose izinto eziluhlaza zixutywe kwi-molar ratio ye-1: 1.5: 1.5, kwaye i-MA idityaniswe yinkqubo entsha ye-mechanochemical reaction.Ngokugxininisa i-131I kwizixhobo zebhetri ezishisayo, isivuno esipheleleyo se-131I emva koxinaniso yi-90. I-%, kunye nesisombululo esifunyenweyo se-131I [NaI] sine-concentration ephezulu ye-radioactive (1.7TBq / mL), ngaloo ndlela iqonda ukusetyenziswa kwee-capsules ze-dose131I [NaI] enkulu yonyango lomhlaza we-thyroid.
Ukushwankathela, kwixesha elizayo, iitemplates ezincinci zeemolekyuli zinokuphuhliswa kwakhona ukwakha izakhiwo ze-pore eziyalelwe ngamanqanaba amaninzi, ukulungelelanisa ngokufanelekileyo isakhiwo, i-morphology kunye neepropati zeekhemikhali zomhlaba zezixhobo, kunye nokuvelisa indawo enkulu yomhlaba kunye nomyalelo we-wormhole MA.Jonga iitemplates ezitshiphu kunye nemithombo ye-aluminiyam, wandise inkqubo yokudibanisa, ucacise indlela yokudibanisa kunye nokukhokela inkqubo.
Indlela yokuguqulwa kwe-2 MA
Iindlela zokusabalalisa ngokulinganayo amacandelo asebenzayo kwi-MA carrier ziquka ukukhulelwa, i-in-situ synthe-sis, imvula, i-ion exchange, ukuxuba oomatshini kunye nokunyibilika, phakathi kwazo ezimbini zokuqala zisetyenziswa ngokuqhelekileyo.
2.1 in-situ synthesis method
Amaqela asetyenziselwa ukuguqulwa komsebenzi ayongezwa kwinkqubo yokulungiselela i-MA ukuguqula nokuzinzisa ukwakheka kwe-skeleton yezinto kunye nokuphucula ukusebenza kwe-catalytic.Inkqubo iboniswe kuMfanekiso 2. Liu et al.i-Ni/Mo-Al2O3in situ eyenziwe nge-P123 njenge template.Zombini i-Ni kunye ne-Mo zachithwa ngokulandelelana kweendlela ze-MA, ngaphandle kokutshabalalisa isakhiwo se-mesoporous se-MA, kwaye ukusebenza kwe-catalytic kwaphuculwa ngokucacileyo.Ukwamkela indlela yokukhula kwe-in-situ kwi-gamma-al2o3substrate eyenziweyo, xa ithelekiswa ne-γ-Al2O3, i-MnO2-Al2O3 inendawo enkulu ye-BET yendawo ethile kunye nomthamo we-pore, kwaye inokwakheka kwe-mesoporous ye-bimodal kunye nokusabalalisa ubungakanani bepore emxinwa.I-MnO2-Al2O3 inezinga lokubhengeza ngokukhawuleza kunye nokusebenza okuphezulu kwe-F-, kwaye inoluhlu olubanzi lwe-pH yesicelo (pH = 4 ~ 10), efanelekileyo kwiimeko zesicelo soshishino.Ukusebenza ngokutsha kwe-MnO2-Al2O3 kungcono kunoko kwe-γ-Al2O.Uzinzo lwesakhiwo kufuneka luphuculwe ngakumbi.Ukushwankathela, izinto eziguqulweyo ze-MA ezifunyenwe yi-in-situ synthesis zinocwangco olulungileyo lwesakhiwo, intsebenziswano eyomeleleyo phakathi kwamaqela kunye nabathwali be-alumina, indibaniselwano eqinileyo, umthwalo omkhulu wezinto, kwaye akukho lula ukubangela ukuchithwa kwezinto ezisebenzayo kwinkqubo ye-catalytic reaction. , kwaye ukusebenza kwe-catalytic kuphuculwe kakhulu.
Umzobo we-2 Ukulungiswa kwe-MA esebenzayo nge-in-situ synthesis
2.2 indlela yokumitha
Ukuntywilisela i-MA elungiselelwe kwiqela elilungisiweyo, kunye nokufumana izinto eziguquliweyo ze-MA emva konyango, ukuze kuqatshelwe imiphumo ye-catalysis, i-adsorption kunye nokunye okunjalo.Cai et al.ilungisiwe i-MA esuka kwi-P123 nge-sol-gel indlela, kwaye ifakwe kwi-ethanol kunye ne-tetraethylenepentamine isisombululo sokufumana i-amino modified MA impahla kunye nokusebenza okunamandla kwe-adsorption.Ukongeza, uBelkacemi et al.ifakwe kwi-ZnCl2solution ngenkqubo efanayo yokufumana i-odolo ye-zinc doped modified MA materials.Indawo ethile yendawo kunye nomthamo we-pore yi-394m2 / g kunye ne-0.55 cm3 / g, ngokulandelanayo.Xa kuthelekiswa nendlela yokwenziwa kwe-in-situ, indlela yokumilisela inokusasazwa kwento engcono, ubume obuzinzileyo be-mesoporous kunye nokusebenza kakuhle kwe-adsorption, kodwa amandla okunxibelelana phakathi kwezinto ezisebenzayo kunye nomthwali we-alumina ubuthathaka, kwaye umsebenzi we-catalytic uphazamiseka ngokulula zizinto zangaphandle.
3 inkqubela yomsebenzi
I-synthesis yomhlaba onqabileyo we-MA kunye neepropati ezikhethekileyo yindlela yophuhliso kwixesha elizayo.Okwangoku, kukho iindlela ezininzi zokudibanisa.Iiparamitha zenkqubo zichaphazela ukusebenza kwe-MA.Indawo ethile yendawo, umthamo we-pore kunye ne-pore diameter ye-MA inokulungiswa ngohlobo lwetemplate kunye nokubunjwa kwe-aluminium precursor.Ukushisa kwe-calcination kunye ne-polymer template concentration ichaphazela indawo ethile yendawo kunye nomthamo we-pore we-MA.I-Suzuki kunye ne-Yamauchi yafumanisa ukuba ukushisa kwe-calcination kwanda ukusuka kwi-500 ℃ ukuya kwi-900 ℃.I-aperture inokunyuswa kwaye indawo ephezulu ingancitshiswa.Ukongezelela, unyango olunqabileyo lokuguqulwa komhlaba luphucula umsebenzi, ukuzinza kwe-thermal surface, ukuzinza kwesakhiwo kunye ne-acidity yomhlaba wezinto ze-MA kwinkqubo ye-catalytic, kwaye idibana nophuhliso lwe-MA functionalization.
3.1 I-Defluorination Adsorbent
I-fluorine emanzini okusela e-China iyingozi kakhulu.Ukongeza, ukonyuka komxholo we-fluorine kwisisombululo se-zinc sulfate kwimizi-mveliso kuya kukhokelela ekudlekeni kwepleyiti ye-electrode, ukuwohloka kwendawo yokusebenza, ukuhla komgangatho we-zinc yombane kunye nokuncipha komyinge wamanzi aphinda asetyenziswe kwinkqubo yokwenza iasidi. kunye nenkqubo ye-electrolysis yesithando somlilo sokutshisa igesi yomlilo.Okwangoku, indlela ye-adsorption iyona nto inomtsalane phakathi kweendlela eziqhelekileyo zokuchithwa kwamanzi.Nangona kunjalo, kukho iintsilelo, ezifana nomthamo we-adsorption ompofu, uluhlu oluncinci lwe-pH olukhoyo, ukungcola okwesibini kunye nokunye.Ikhabhoni esebenzayo, i-amorphous alumina, i-alumina esebenzayo kunye nezinye ii-adsorbents zisetyenziselwe ukuchithwa kwamanzi, kodwa ixabiso le-adsorbents liphezulu, kwaye umthamo we-adsorption wesisombululo se-F-in neutral okanye ugxininiso oluphezulu luphantsi. ifundelwe i-adsorbent yokususa i-fluoride ngenxa yobudlelwane bayo obuphezulu kunye nokukhetha kwayo kwi-fluoride kwixabiso elingathathi hlangothi le-pH, kodwa inqunyanyiswa kukungafumani mandla okungena kakuhle kwe-fluoride, kwaye kuphela kwi-pH <6 enokuthi ibe nokusebenza kakuhle kwe-fluoride adsorption.MA iye yatsala ingqalelo ebanzi. kulawulo longcoliseko lokusingqongileyo ngenxa yendawo enkulu ethile, isiphumo sobungakanani bepore eyodwa, ukusebenza kwesiseko se-asidi, ukuzinza kwe-thermal kunye nomatshini.Kundu et al.ilungiswe i-MA kunye nomthamo omkhulu we-fluorine adsorption we-62.5 mg / g.Umthamo we-fluorine adsorption ye-MA ichaphazeleka kakhulu yimpawu zayo zesakhiwo, njengendawo ethile yendawo, amaqela asebenzayo angaphezulu, ubukhulu be-pore kunye nobukhulu obupheleleyo be-pore.Ukulungiswa kwesakhiwo kunye nokusebenza kwe-MA yindlela ebalulekileyo yokuphucula ukusebenza kwayo.
Ngenxa ye-asidi enzima ye-La kunye nesiseko esinzima se-fluorine, kukho ubudlelwane obuqinileyo phakathi kwe-La kunye ne-fluorine ions.Kwiminyaka yakutshanje, ezinye izifundo ziye zafumanisa ukuba iLa njengemodyuli inokuphucula amandla e-adsorption ye-fluoride.Nangona kunjalo, ngenxa yozinzo oluphantsi lwesakhiwo se-adsorbents yomhlaba enqabileyo, imihlaba enqabileyo kakhulu ifakwe kwisisombululo, okukhokelela kungcoliseko lwamanzi lwesibini kunye nokwenzakala kwimpilo yabantu.Kwelinye icala, ukuxinana okuphezulu kwe-aluminiyam kwindawo esemanzini yenye yeetyhefu kwimpilo yabantu.Ngoko ke, kuyimfuneko ukulungiselela uhlobo lwe-adsorbent edibeneyo kunye nokuzinza okulungileyo kwaye akukho leaching okanye i-leaching encinci yezinye izinto kwinkqubo yokususa i-fluorine.I-MA ilungiswe nguLa kunye noCe yalungiswa ngendlela yokukhulelwa (i-La / MA kunye ne-Ce / MA).Iioksidi zomhlaba ezinqabileyo zalayishwa ngempumelelo kumphezulu we-MA okokuqala, obunomgangatho ophezulu wokusebenza kwe-defluorination. Iindlela eziphambili zokususa i-fluorine yi-electrostatic adsorption kunye ne-chemical adsorption, umtsalane we-electron we-surface positive charge kunye ne-ligand exchange reaction idibanisa ne-surface hydroxyl, Iqela elisebenzayo le-hydroxyl kumphezulu we-adsorbent livelisa ibhondi ye-hydrogen nge-F-, ukuguqulwa kwe-La kunye ne-Ce kuphucula amandla e-adsorption ye-fluorine, i-La/MA iqulethe iindawo ezininzi ze-hydroxyl adsorption, kunye nomthamo we-adsorption we-F ulungelelaniswa ne-La/MA. >Ce/MA>MA.Ngokunyuka koxinzelelo lokuqala, umthamo we-adsorption we-fluorine uyenyuka.Impembelelo ye-adsorption ingcono xa i-pH iyi-5 ~ 9, kunye nenkqubo ye-adsorption ye-fluorine ihambelana nemodeli ye-adsorption ye-Langmuir isothermal.Ukongeza, ukungcola kwe-ion ye-sulfate kwi-alumina kunokuchaphazela kakhulu umgangatho weesampuli.Nangona uphando oluhambelanayo kumhlaba onqabileyo oguqulwayo we-alumina wenziwa, uninzi lophando lujolise kwinkqubo ye-adsorbent, okunzima ukuyisebenzisa kwishishini.Kwixesha elizayo, sinokufunda indlela yokuqhawula i-fluorine complex kwisisombululo se-zinc sulfate. kunye neempawu zokufuduka kwee-ion ze-fluorine, ukufumana i-ion adsorbent esebenzayo, ephantsi kunye ne-fluorine ehlaziyiweyo ye-defluorination ye-zinc sulfate isisombululo kwi-zinc hydrometallurgy system, kunye nokuseka imodeli yokulawula inkqubo yokuphatha isisombululo esiphezulu se-fluorine esekelwe kumhlaba onqabileyo we-MA nano adsorbent.
3.2 I-Catalyst
3.2.1 Uhlengahlengiso olomileyo lwemethane
Umhlaba onqabileyo unokuhlengahlengisa i-asidi (isiseko) sezinto ezinobunwele, ukwandisa isithuba se-oksijini, kunye nokudibanisa i-catalysts kunye nokusabalalisa okufanayo, isikali se-nanometer kunye nokuzinza.Ihlala isetyenziselwa ukuxhasa iintsimbi ezihloniphekileyo kunye neenguqu zesinyithi ukwenza i-methanation ye-CO2.Okwangoku, imathiriyeli ye-mesoporous enqabileyo eguqulelwe emhlabeni iphuhlisa kwi-methane dry reforming (MDR), ukuthotywa kwe-photocatalytic ye-VOCs kunye nokucoca irhasi yomsila. Co, Fe, njl.), I-Ni/Al2O3catalyst isetyenziswa ngokubanzi kumsebenzi wayo ophezulu we-catalytic kunye nokukhetha, ukuzinza okuphezulu kunye neendleko eziphantsi ze-methane.Nangona kunjalo, i-sintering kunye ne-carbon deposition ye-Ni nanoparticles ebusweni be-Ni / Al2O3 ikhokelela ekucinyweni ngokukhawuleza kwe-catalyst.Ke ngoko, kuyafuneka ukongeza okukhawulezileyo, ukuguqula umthwali wecatalyst kunye nokuphucula indlela yokulungiselela ukuphucula umsebenzi we-catalytic, uzinzo kunye nokumelana nokutsha.Ngokubanzi, ii-oksidi zomhlaba ezinqabileyo zingasetyenziswa njengabakhuthazi bezakhiwo kunye ne-elektroniki kwii-catalysts ezingafaniyo, kwaye i-CeO2 iphucula ukusasazeka kwe-Ni kwaye iguqula iipropati ze-metallic Ni ngokusebenzisa intsebenziswano eqinile yenkxaso yentsimbi.
I-MA isetyenziswa ngokubanzi ukunyusa ukusasazwa kwesinyithi, kwaye ibonelele ngothintelo kwiintsimbi ezisebenzayo ukuthintela ukudityaniswa kwazo.I-La2O3 enomthamo ophezulu wokugcina i-oksijini iphakamisa ukuxhathisa kwekhabhoni kwinkqubo yokuguqulwa, kwaye i-La2O3 ikhuthaza ukusasazwa kwe-Co kwi-mesoporous alumina, enomsebenzi ophezulu wokuguqula kunye nokuqina.I-La2O3promoter yandisa umsebenzi we-MDR we-Co / MA catalyst, kunye ne-Co3O4and CoAl2O4phases zenziwa kwi-catalyst surface.Nangona kunjalo, i-La2O3 ehlakazeke kakhulu ineenkozo ezincinci ze-8nm ~ 10nm.Kwinkqubo ye-MDR, i-in-situ intsebenziswano phakathi kwe-La2O3 kunye ne-CO2formed i-La2O2CO3mesophase, ebangele ukupheliswa okusebenzayo kwe-CxHy kumphezulu we-catalyst.I-La2O3 ikhuthaza ukucuthwa kwe-hydrogen ngokubonelela ngokuxinana kwe-electron ephezulu kunye nokwandisa isithuba se-oksijini kwi-10% Co/MA.Ukongezwa kweLa2O3 kunciphisa amandla abonakalayo okusebenza kwe-CH4consumption.Ngoko ke, izinga lokuguqulwa kwe-CH4 linyuke laya kwi-93.7% kwi-1073K K. Ukongezwa kwe-La2O3 kuphuculwe umsebenzi we-catalytic, kukhuthaze ukuncitshiswa kwe-H2, ukwandisa inani leendawo ezisebenzayo ze-Co0, zavelisa i-carbon ephantsi kunye nokwandisa isithuba se-oksijini kwi-73.3%.
I-Ce kunye ne-Pr zixhaswe kwi-Ni/Al2O3catalyst ngendlela elinganayo yokufakwa kwevolumu kwi-Li Xiaofeng.Emva kokongeza i-Ce kunye ne-Pr, ukukhetha kwi-H2 kwanda kwaye ukukhetha kwi-CO kwehlile.I-MDR eguqulelwe ngu-Pr inekhono elihle kakhulu le-catalytic, kunye nokukhethwa kwe-H2 kwanda ukusuka kwi-64.5% ukuya kwi-75.6%, ngelixa ukukhethwa kwe-CO kwehla kwi-31.4% uPeng Shujing et al.isetyenziswe indlela ye-sol-gel, i-Ce-modified MA yalungiswa nge-aluminium isopropoxide, i-solvent ye-isopropanol kunye ne-cerium nitrate hexahydrate.Indawo ethile yendawo yemveliso yanda kancinci.Ukongezwa kwe-Ce kunciphise ukudityaniswa kwee-nanoparticles ezinjengentonga kumphezulu we-MA.Amanye amaqela e-hydroxyl kumphezulu we-γ- Al2O3 ayegqunywe ngokusisiseko yi-Ce compounds.Ukuzinza kwe-thermal ye-MA kwaphuculwa, kwaye akukho kuguqulwa kwesigaba se-crystal kwenzeka emva kokubala kwi-1000 ℃ kwiiyure ze-10. Wang Baowei et al.ilungiswe izinto ze-MA CeO2-Al2O4by coprecipitation method.I-CeO2eneenkozo ezincinci zecubic zasasazwa ngokufanayo kwi-alumina.Emva kokuxhasa i-Co kunye ne-Mo kwi-CeO2-Al2O4, intsebenziswano phakathi kwe-alumina kunye necandelo elisebenzayo i-Co kunye ne-Mo yathintelwa ngokufanelekileyo yi-CEO2.
Abagqugquzeli bomhlaba obunqabileyo (La, Ce, y kunye ne-Sm) badityaniswe ne-Co / MA catalyst ye-MDR, kwaye inkqubo iboniswe kwifig.3. abagqugquzeli bomhlaba obunqabileyo banokuphucula ukusabalalisa kwe-Co kwi-carrier ye-MA kwaye banqande i-agglomeration ye-co particles.incinci isayizi ye-particle, inamandla intsebenziswano ye-Co-MA, inamandla amandla okwenza i-catalytic kunye ne-sintering kwi-YCo / MA catalyst, kunye nemiphumo emihle yabakhuthazi abaninzi kumsebenzi we-MDR kunye ne-carbon deposition.Fig.I-4 yi-HRTEM iMage emva konyango lwe-MDR kwi-1023K, i-Co2: i-ch4: i-N2 = 1 ∶ 1 ∶ 3.1 kwiiyure ze-8.Amasuntswana e-Co akhona ngohlobo lwamabala amnyama, ngelixa abathwali be-MA bekho ngohlobo lwengwevu, exhomekeke kumahluko wobuninzi be-electron.kumfanekiso we-HRTEM nge-10% Co/MA (umzobo 4b), i-agglomeration ye-Co metal particles ibonwa kwi-ma carriersUkongezwa komgqugquzeli womhlaba onqabileyo kunciphisa amasuntswana e-Co ukuya kwi-11.0nm ~ 12.5nm.I-YCo/MA inonxibelelwano oluluqilima lwe-Co-MA, kwaye ukusebenza kwayo kwe-sintering kungcono kunezinye ii-catalysts.ukongeza, njengoko kubonisiwe kumakhiwane.I-4b ukuya kwi-4f, i-carbon nanowires engenanto (CNF) iveliswa kwii-catalysts, ezihlala zidibanisa nokuhamba kwegesi kwaye zithintele i-catalyst ukuba ingasebenzi.
Umzobo 3 Impembelelo yokongezwa komhlaba onqabileyo kwiipropathi ezibonakalayo kunye neekhemikhali kunye nokusebenza kwe-MDR ye-Catalyst ye-Co/MA
3.2.2 I-deoxidation catalyst
I-Fe2O3 / Meso-CeAl, i-Ce-doped Fe-based deoxidation catalyst, yalungiswa nge-oxidative dehydrogenation ye-1-butene ene-CO2as i-oxidant ethambileyo, kwaye isetyenziswe kwi-synthesis ye-1,3-butadiene (BD).I-Ce yayisasazeke kakhulu kwi-alumina matrix, kwaye i-Fe2O3/meso yahlakazeka kakhuluFe2O3/Meso-CeAl-100 i-catalyst ayinayo kuphela iintlobo zentsimbi ezisasazeke kakhulu kunye nezakhiwo ezilungileyo, kodwa inomthamo olungileyo wokugcina ioksijini, ke ine-adsorption elungileyo kunye namandla okusebenza. yeCO2.Njengoko kubonisiwe kuMfanekiso we-5, imifanekiso ye-TEM ibonisa ukuba i-Fe2O3/Meso-CeAl-100 iqhelekileIbonisa ukuba isakhiwo sejelo esifana nentshulube se-MesoCeAl-100 sikhululekile kwaye sinobukroti, esiluncedo ekusasazweni kwezithako ezisebenzayo, ngelixa i-Ce isasazwe kakhulu. yenziwe ngempumelelo kwimatrix ye-alumina.Isixhobo sokugquma sesinyithi esinexabiso eliphezulu esidibana nomgangatho ophantsi we-ultra-low emission yezithuthi uye waphuhlisa ubume bepore, uzinzo oluhle lwe-hydrothermal kunye nomthamo omkhulu wokugcina ioksijini.
3.2.3 I-Catalyst yeZithuthi
I-Pd-Rh ixhasa i-quaternary aluminiyam esekwe kwizakhiwo zomhlaba ezinqabileyo ze-AlCeZrTiOx kunye ne-AlLaZrTiOx ukufumana izixhobo zokugquma iimoto.I-mesoporous aluminium-based based rare earth complex Pd-Rh/ALC ingasetyenziswa ngempumelelo njenge-CNG i-exhaust purification catalyst enokuqina okulungileyo, kunye nokuguqulwa kokusebenza kakuhle kwe-CH4, eyona nto iphambili ye-CNG ye-exhaust gas, iphezulu njenge-97.8%.Yamkela indlela ye-hydrotherMAl enenyathelo elinye lokulungiselela ukuba umhlaba onqabileyo udibanise imathiriyeli ukuze ukwazi ukuzihlanganisa, ii-precursors ze-mesoporous eziyalelweyo ezinemeko yemetastable kunye nokudityaniswa okuphezulu zadityaniswa, kunye ne-synthesis ye-RE-Al ihambelana nemodeli "yeyunithi yokukhula komdibaniso" , ngaloo ndlela ukuqonda ukucocwa kombhobho wemoto emva kokunyuswa kweendlela ezintathu zokuguqula i-catalytic.
Umfanekiso we-4 HRTEM imifanekiso ye-ma (a), Co/ MA(b), LaCo/MA(c), CeCo/MA(d), YCo/MA(e) kunye ne-SmCo/MA(f)
Umfanekiso wesi-5 we-TEM (A) kunye ne-EDS isazobe (b,c) ye-Fe2O3/Meso-CeAl-100
3.3 ukusebenza okuqaqambileyo
Ii-elektroni zezinto ezinqabileyo zomhlaba zivuya ngokulula kwinguqu phakathi kwamanqanaba ohlukeneyo amandla kwaye zikhuphe ukukhanya.Iiyoni zomhlaba ezinqabileyo zihlala zisetyenziswa njengezivuseleli ukuze kulungiswe imathiriyeli ekhanyayo.Iiyoni zomhlaba ezinqabileyo zinokulayishwa kumphezulu we-aluminiyam yephosphate ehollow microspheres ngendlela yokucoprecipitation kunye nendlela yokutshintshiselana nge-ion, kunye nemathiriyeli yokukhanya iAlPO4∶RE(La,Ce,Pr,Nd) inokulungiswa.I-luminescent wavelength ikwindawo ekufutshane ye-ultraviolet.MA yenziwe kwiifilimu ezincinci ngenxa ye-inertia yayo, i-dielectric ephantsi rhoqo kunye ne-conductivity ephantsi, eyenza ukuba isebenze kwizixhobo zombane kunye ne-optical, iifilimu ezincinci, izithintelo, izinzwa, njl. zisetyenziselwa ukuva impendulo yekristali ene-dimensional photonic, ukuveliswa kwamandla kunye ne-anti-reflection.Ezi zixhobo zineefilimu ezipakishweyo ezinobude obucacileyo bendlela yokukhanya, ngoko ke kuyimfuneko ukulawula isalathisi se-refractive kunye nobukhulu.Okwangoku, i-titanium dioxide kunye ne-zirconium oxide enesalathisi esiphezulu se-refractive kunye ne-silicon dioxide ene-low refractive index zihlala zisetyenziselwa ukuyila nokwakha izixhobo ezinjalo. .Uluhlu lwezinto ezifumanekayo ezineempawu ezahlukeneyo zeekhemikhali zomhlaba zandisiwe, okwenza kube lula ukuyila i-photon sensors ephezulu.Ukuqaliswa kweefilimu ze-MA kunye ne-oxyhydroxide ekuyilweni kwezixhobo ze-optical kubonisa amandla amakhulu ngenxa yokuba i-index refractive index ifana ne-silicon dioxide.Kodwa iipropati zeekhemikhali zihluke.
3.4 ukuzinza kwe-thermal
Ngokunyuka kweqondo lokushisa, i-sintering ichaphazela kakhulu umphumo wokusetyenziswa kwe-MA catalyst, kwaye indawo ethile yendawo iyancipha kwaye i-γ-Al2O3in isigaba se-crystalline siguqulela kwi-δ kunye ne-θ ukuya kwizigaba ze-χ.Izinto zomhlaba ezinqabileyo zinozinzo olululo lweekhemikhali kunye nokuzinza kwe-thermal, ukuguquguquka okuphezulu, kunye nezixhobo ezifumaneka lula kunye nezixhobo eziluhlaza.Ukongezwa kwezinto ezinqabileyo zomhlaba kunokuphucula ukuzinza kwe-thermal, ukumelana nobushushu obuphezulu be-oxidation kunye neempawu zomatshini zomqhubi, kunye nokulungelelanisa i-asidi yomphezulu we-carrier.La kunye ne-Ce zezona ziqhelekileyo zisetyenziswa kwaye zifundelwa ukuguqulwa kwezinto.U-Lu Weiguang kunye nabanye bafumanisa ukuba ukongezwa kwezinto ezinqabileyo zomhlaba kuthintele ngokufanelekileyo ukusasazwa kobuninzi be-alumina, i-La kunye ne-Ce ikhusele amaqela e-hydroxyl kumphezulu we-alumina, i-inhibited sintering kunye nokuguqulwa kwesigaba, kunye nokunciphisa umonakalo wobushushu obuphezulu kwisakhiwo se-mesoporous. .I-alumina elungisiweyo isenayo indawo ephezulu ephezulu kunye nomthamo wepore. Nangona kunjalo, kakhulu okanye encinci kakhulu into enqabileyo yomhlaba iya kunciphisa ukuzinza kwe-thermal ye-alumina.Li Yanqiu et al.yongezelela i-5% i-La2O3to γ-Al2O3, eyaphucula ukuzinza kwe-thermal kunye nokwandisa umthamo we-pore kunye nommandla othile we-alumina carrier.Njengoko kunokubonwa kwi-Figure 6, i-La2O3 yongezwe kwi-γ-Al2O3,Phucula uzinzo lwe-thermal ye-carrier ye-composite yomhlaba enqabileyo.
Kwinkqubo ye-doping nano-fibrous particles kunye ne-La ukuya ku-MA, indawo ye-BET yomhlaba kunye nomthamo we-pore we-MA-La uphezulu kune-MA xa ubushushu bonyango lobushushu bunyuka, kwaye i-doping nge-La inefuthe elicacileyo lokuthomalalisa kwi-sintering ephezulu. ubushushu.njengoko kubonisiwe kwifig.I-7, ngokunyuka kweqondo lokushisa, i-La inqanda ukusabela kokukhula okuziinkozo kunye nokuguqulwa kwesigaba, ngelixa amakhiwane.I-7a kunye ne-7c ibonisa ukuqokelela kwee-nano-fibrous particles.emkhiwaneni.I-7b, ububanzi beengqungquthela ezinkulu eziveliswa yi-calcination kwi-1200 ℃ malunga ne-100nm.Ibonisa i-sintering ebalulekileyo ye-MA.Ukongeza, xa kuthelekiswa ne-MA-1200, i-MA-La-1200 ayihlanganisi emva kokunyanga ubushushu.Ngokudityaniswa kweLa, amasuntswana e-nano-fiber abe nobuchule obungcono bokuntywila.nokuba kwiqondo lobushushu eliphezulu calcination, doped La isasasazwe kakhulu phezu MA umphezulu.I-La modified MA ingasetyenziselwa njengomphathi we-Pd catalyst kwi-C3H8oxidation reaction.
Isazobe sesi-6 imodeli yolwakhiwo lwe-alumina enyibilikayo eneziqalelo zomhlaba ezinqabileyo nezingenazo
Umfanekiso we-7 TEM imifanekiso ye-MA-400 (a), MA-1200 (b), MA-La-400 (c) kunye ne-MA-La-1200 (d)
4 Isiphelo
Inkqubela phambili yolungiselelo kunye nokusetyenziswa okusebenzayo kwezinto ezinqabileyo zomhlaba eziguqulweyo ze-MA ziyaziswa.Umhlaba oRare modified MA isetyenziswa kakhulu.Nangona uphando oluninzi lwenziwe kwi-catalytic application, ukuzinza kwe-thermal kunye ne-adsorption, izixhobo ezininzi zineendleko eziphezulu, ixabiso eliphantsi le-doping, ulungelelwaniso olubi kwaye kunzima ukuba kumashishini.Lo msebenzi ulandelayo kufuneka wenziwe kwixesha elizayo: lungisa ukubunjwa kunye nesakhiwo somhlaba onqabileyo oguquliweyo we-MA, khetha inkqubo efanelekileyo, Dibana nophuhliso olusebenzayo;Ukuseka imodeli yolawulo lwenkqubo esekelwe kwinkqubo yokusebenza yokunciphisa iindleko kunye nokuqonda imveliso yoshishino;Ukuze kwandiswe iingenelo zobutyebi bomhlaba obunqabileyo baseTshayina, kufuneka siphonononge indlela yokuguqulwa kwe-MA enqabileyo yomhlaba, siphucule ithiyori kunye nenkqubo yokulungiselela umhlaba onqabileyo oguqulwe i-MA.
IProjekthi yeNgxowa-mali: iProjekthi yeNzululwazi neTekhnoloji iyonke ye-Innovation (2011KTDZ01-04-01);IPhondo laseShaanxi lika-2019 iProjekthi yoPhando lwezeNzululwazi eKhethekileyo (19JK0490);2020 iprojekthi ekhethekileyo yophando lwenzululwazi yeKholeji yaseHuaqing, iXi 'an University of Architecture and Technology (20KY02)
Umthombo: Umhlaba onqabileyo
Ixesha lokuposa: Jul-04-2022