CeO2iyingxenye ebalulekile yezinto ezingavamile zomhlaba.Iisici somhlaba esingavamile i-ceriuminesakhiwo se-electronic sangaphandle esiyingqayizivele - 4f15d16s2.Isendlalelo sayo esikhethekile esingu-4f singagcina futhi sikhulule ama-electron ngempumelelo, kwenze ama-cerium ion aziphathe ku+3 valence state kanye+4 valence state.Ngakho-ke, izinto ze-CeO2 zinezimbobo eziningi ze-oxygen, futhi zinekhono elihle kakhulu lokugcina nokukhulula umoya-mpilo.Ukuguqulwa okufanayo kwe-Ce (III) kanye ne-Ce (IV) futhi kunikeza izinto ze-CeO2 amandla ayingqayizivele okunciphisa i-oxidation.Uma kuqhathaniswa nezinto ezisetshenziswa ngobuningi, i-nano CeO2, njengohlobo olusha lwezinto ezingaphili, ithole ukunakwa okusabalele ngenxa yendawo yayo ethile ephezulu, ukugcinwa komoya-mpilo okuhle kakhulu kanye nekhono lokukhulula, i-oxygen ion conductivity, ukusebenza kabusha kwe-redox, kanye ne-high-temperature esheshayo yokusabalalisa isikhala se-oxygen. ikhono.Njengamanje kunenani elikhulu lemibiko yocwaningo kanye nezinhlelo zokusebenza ezihlobene ezisebenzisa i-nano CeO2 njengama-catalysts, ama-catalyst carriers noma izithasiselo, izingxenye ezisebenzayo, nama-adsorbents.
1. Indlela yokulungiselela ye-nanometeri-cerium oxide
Njengamanje, izindlela ezijwayelekile zokulungiselela i-nano ceria ikakhulukazi zifaka indlela yamakhemikhali kanye nendlela yomzimba.Ngokwezindlela ezahlukene zamakhemikhali, izindlela zamakhemikhali zingahlukaniswa ngendlela yemvula, indlela ye-hydrothermal, indlela ye-solvothermal, indlela ye-sol gel, indlela ye-microemulsion kanye nendlela ye-electrodeposition;Indlela engokwenyama ngokuyinhloko iyindlela yokugaya.
1.1 Indlela yokugaya
Indlela yokugaya yokulungisa i-nano ceria ngokuvamile isebenzisa ukugaya isihlabathi, okunobuhle bezindleko eziphansi, ubungane bemvelo, isivinini sokucubungula okusheshayo, nekhono eliqinile lokucubungula.Njengamanje iyindlela yokucubungula ebaluleke kakhulu embonini ye-nano ceria.Isibonelo, ukulungiswa kwempushana yokupholisha i-nano cerium oxide ngokuvamile kusebenzisa inhlanganisela yokubala nokugaya isihlabathi, futhi izinto zokusetshenziswa ze-cerium based denitration catalysts nazo ziyaxutshwa ukuze zelashwe ngaphambilini noma zelashwe ngemva kokubala kusetshenziswa ukugaya isihlabathi.Ngokusebenzisa izilinganiso zezinhlayiyana ezihlukene zobukhulu bezinhlayiyana zokugaya ubuhlalu, i-nano ceria ene-D50 esukela kumashumi kuya kumakhulu ama-nanometer ingatholwa ngokulungiswa.
1.2 Indlela yemvula
Indlela yezulu isho indlela yokulungisa impushana eqinile ngokuna, ukuhlukaniswa, ukuwasha, ukomisa, nokubalwa kwezinto ezingavuthiwe ezincibilikisiwe kuzincibilikisi ezifanele.Indlela yemvula isetshenziswa kakhulu ekulungiseni umhlaba ongavamile kanye nama-nanomaterials ane-doped, ngezinzuzo ezifana nenqubo elula yokulungiselela, ukusebenza kahle okuphezulu, kanye nezindleko eziphansi.Kuyindlela evame ukusetshenziswa yokulungiselela i-nano ceria nezinto zayo eziyinhlanganisela embonini.Le ndlela ingalungisa i-nano ceria ene-morphology ehlukene kanye nosayizi wezinhlayiyana ngokushintsha izinga lokushisa lemvula, ukugxiliswa kwezinto ezibonakalayo, inani le-pH, isivinini semvula, isivinini esinyakazayo, isifanekiso, njll. Izindlela ezivamile zincike emvula yama-ion e-cerium avela ku-ammonia ekhiqizwa ukubola kwe-urea, futhi ukulungiswa kwe-nano ceria microspheres kulawulwa yi-citrate ions.Kungenjalo, ama-ion e-cerium angancishiswa yi-OH - akhiqizwe ku-hydrolysis ye-sodium citrate, bese efukanyelwa futhi enziwe nge-calcined ukuze kulungiswe i-flake njenge-nano ceria microspheres.
1.3 Izindlela ze-Hydrothermal kanye ne-solvothermal
Lezi zindlela ezimbili zibhekisela endleleni yokulungiselela imikhiqizo ngokusabela okuphezulu kokushisa kanye nokucindezela okuphezulu ekushiseni okubalulekile ohlelweni oluvaliwe.Lapho i-solvent yokusabela ingamanzi, ibizwa ngokuthi indlela ye-hydrothermal.Ngokufanayo, lapho i-solvent solvent iyi-solvent ephilayo, ibizwa ngokuthi indlela ye-solvothermal.Izinhlayiya ze-nano ezihlanganisiwe zinokuhlanzeka okuphezulu, ukuhlakazeka okuhle kanye nezinhlayiya ezifanayo, ikakhulukazi ama-nano powders ane-morphology ehlukene noma ubuso obukhethekile bekristalu obuveziwe.Chaza i-cerium chloride emanzini acwecwe, ugovuze bese wengeza isixazululo se-sodium hydroxide.Yenza i-hydrothermal ku-170 ℃ amahora angu-12 ukuze ulungiselele i-cerium oxide nanorod enezindiza eziveziwe (111) kanye (110) zekristalu.Ngokulungisa izimo zokusabela, ingxenye (110) yezindiza zekristalu ezindizeni zekristalu eziveziwe ingandiswa, kuthuthukiswe umsebenzi wabo we-catalytic.Ukulungisa i-solvent yokusabela kanye ne-surface ligands kungase futhi kukhiqize izinhlayiya ze-nano ceria nge-hydrophilicity ekhethekile noma i-lipophilicity.Isibonelo, ukwengeza ama-acetate ions esigabeni samanzi kungalungisa i-monodisperse hydrophilic cerium oxide nanoparticles emanzini.Ngokukhetha i-solvent engeyona i-polar kanye nokwethula i-oleic acid njenge-ligand ngesikhathi sokuphendula, i-monodisperse lipophilic ceria nanoparticles ingalungiswa ku-non-polar organic solvents.(Bheka umfanekiso 1)
Umfanekiso 1 I-Monodisperse i-nano ceria eyindilinga kanye ne-nano ceria emise okwenduku
1.4 Indlela yejeli ye-sol
Indlela ye-sol gel iyindlela esebenzisa ezinye noma izinhlanganisela eziningana njengama-precursors, yenza ukusabela kwamakhemikhali njenge-hydrolysis esigabeni se-liquid ukuze kwakhiwe i-sol, bese yakha ijeli ngemva kokuguga, futhi ekugcineni iyomisa kanye nama-calcines ukuze kulungiswe izimpushana ze-ultrafine.Le ndlela ifaneleka ngokukhethekile ukulungiselela i-nano ceria composite composite nanomaterials ehlakazeke kakhulu, njenge-cerium iron, i-cerium titanium, i-cerium zirconium namanye ama-nano oxide ayinhlanganisela, okuye kwabikwa emibikweni eminingi.
1.5 Ezinye izindlela
Ngaphezu kwalezi zindlela ezingenhla, kukhona nendlela yokugcoba i-micro, indlela yokwenziwa kwe-microwave, indlela ye-electrodeposition, indlela yokushiswa komlilo we-plasma, indlela ye-ion-exchange membrane electrolysis kanye nezinye izindlela eziningi.Lezi zindlela zinokubaluleka okukhulu ocwaningweni nasekusetshenzisweni kwe-nano ceria.
Ukusetshenziswa kwe-2-nanometer cerium oxide ekwelashweni kwamanzi
I-Cerium iyinto eningi kakhulu phakathi kwezakhi zomhlaba ezingavamile, ezinamanani aphansi kanye nokusetshenziswa okubanzi.I-Nanometer ceria kanye nezinhlanganisela zayo kudonse ukunaka okukhulu emkhakheni wokwelashwa kwamanzi ngenxa yendawo yawo ethile ephezulu, umsebenzi ophezulu we-catalytic kanye nokuzinza okuhle kakhulu kwesakhiwo.
2.1 Ukusetshenziswa kweI-Nano Cerium oxideEkuhlanzeni Amanzi Nge-Adsorption Method
Eminyakeni yamuva nje, ngokuthuthukiswa kwezimboni ezifana nemboni ye-electronics, inani elikhulu lamanzi angcolile aqukethe ukungcola okufana ne-iron metal esindayo nama-fluorine ions akhishwe.Ngisho nasezindaweni zokulandela umkhondo, kungabangela umonakalo omkhulu ezintweni eziphila emanzini kanye nendawo ehlala abantu.Izindlela ezivame ukusetshenziswa zihlanganisa i-oxidation, i-flotation, i-osmosis ehlehlayo, i-adsorption, i-nanofiltration, i-biosorption, njll. Phakathi kwazo, ubuchwepheshe be-adsorption buvame ukwamukelwa ngenxa yokusebenza kwayo okulula, izindleko eziphansi, nokusebenza kahle kokwelashwa.Izinto ze-Nano CeO2 zinendawo ethile ephezulu ethile kanye nomsebenzi ongaphezulu ongaphezulu njengama-adsorbents, futhi kube nemibiko eminingi mayelana nokuhlanganiswa kwe-nano CeO2 enezimbotshana nezinto zayo eziyinhlanganisela ezinamamorphologies ahlukene ukuze zikhangise futhi zisuse ama-ion ayingozi emanzini.
Ucwaningo luye lwabonisa ukuthi i-nano ceria inamandla okukhangisa ka-F - emanzini ngaphansi kwezimo ze-asidi ezibuthakathaka.Esixazululweni esine-concentration yokuqala ka-F - ka-100mg/L kanye ne-pH=5-6, umthamo we-adsorption ka-F - ngu-23mg/g, kanti izinga lokususa lika-F - lingu-85.6%.Ngemva kokuyilayisha ebholeni le-polyacrylic acid resin (inani lokulayisha: 0.25g/g), ikhono lokususa lika-F - lingafinyelela ngaphezu kuka-99% lapho ukwelapha umthamo olinganayo we-100mg/L we-F - isixazululo esinamanzi;Lapho ucubungula izikhathi ezingu-120 ivolumu, ngaphezu kuka-90% we-F - ingasuswa.Uma isetshenziselwa i-adsorb phosphate ne-iodate, umthamo we-adsorption ungafinyelela ngaphezu kuka-100mg/g ngaphansi kwesimo se-adsorption esihambisanayo.Izinto ezisetshenzisiwe zingasetshenziswa kabusha ngemva kokwelashwa okulula kwe-desorption kanye ne-neutralization, enezinzuzo eziphezulu zezomnotho.
Ziningi izifundo ezimayelana nokukhangiswa nokwelashwa kwezinsimbi ezinobuthi ezinzima njenge-arsenic, i-chromium, i-cadmium, nomthofu kusetshenziswa i-nano ceria nezinto zayo eziyinhlanganisela.I-pH ye-adsorption elungile iyahlukahluka kuma-ion ensimbi anezimo ezihlukile ze-valence.Isibonelo, isimo se-alkali esibuthakathaka esinokuchema okungathathi hlangothi sinesimo se-adsorption esingcono kakhulu se-As (III), kuyilapho isimo se-adsorption esilungile se-As (V) sifinyelelwa ngaphansi kwezimo ze-asidi ezibuthakathaka, lapho umthamo we-adsorption ungafinyelela ngaphezu kuka-110mg/g ngaphansi kokubili. izimo.Sekukonke, ukuhlanganiswa okuthuthukisiwe kwe-nano ceria nezinto zayo eziyinhlanganisela kungafinyelela ukukhangiswa okuphezulu kanye namazinga okususwa kwama-ion ensimbi esindayo ahlukahlukene ebangeni elibanzi le-pH.
Ngakolunye uhlangothi, i-cerium oxide based nanomaterials iphinde ibe nokusebenza okuvelele ekukhangiseni izinto eziphilayo emanzini angcolile, njenge-acid orange, i-rhodamine B, i-Congo red, njll. umthamo we-adsorption ekukhishweni kodayi bemvelo, ikakhulukazi ekukhipheni okubomvu kwe-Congo, okunamandla okukhangisa angama-942.7mg/g emizuzwini engama-60.
2.2 Ukusetshenziswa kwe-nano ceria kunqubo ye-oxidation ethuthukisiwe
Inqubo ye-oxidation ethuthukisiwe (ama-AOPs kafushane) ihlongozwa ukuthuthukisa uhlelo olukhona lokwelapha olungenamanzi.Inqubo ye-oxidation ethuthukisiwe, eyaziwa nangokuthi ubuchwepheshe be-oxidation ejulile, ibonakala ngokukhiqizwa kwe-hydroxyl radical (· OH), i-superoxide radical (· O2 -), i-oxygen ye-singlet, njll. enekhono eliqinile lokuxilisa.Ngaphansi kwezimo zokusabela zokushisa okuphezulu nokucindezela, ugesi, umsindo, ukukhanya kwe-irradiation, i-catalyst, njll Ngokwezindlela ezahlukene zokukhiqiza ama-radicals mahhala nezimo zokusabela, zingahlukaniswa zibe i-photochemical oxidation, i-catalytic wet oxidation, i-sonochemistry oxidation, i-ozone. i-oxidation, i-electrochemical oxidation, i-Fenton oxidation, njll. (bheka Umfanekiso 2).
Umfanekiso 2 Ukuhlukaniswa Nobuchwepheshe Inhlanganisela Yenqubo Ye-oxidation Ethuthukisiwe
Nano ceriai-heterogeneous catalyst evame ukusetshenziswa ku-Advanced oxidation inqubo.Ngenxa yokuguqulwa okusheshayo phakathi kwe-Ce3+ ne-Ce4+ kanye nomthelela wokunciphisa i-oxidation ngokushesha olethwa ukumuncwa nokukhululwa komoya-mpilo, i-nano ceria inekhono elihle lokuvuselela amandla.Uma isetshenziswa njengomgqugquzeli we-catalyst, ingaphinda ithuthukise ngempumelelo ikhono le-catalytic nokuzinza.Lapho i-nano ceria nezinto zayo eziyinhlanganisela kusetshenziswa njengama-catalyst, izakhiwo ze-catalytic ziyahlukahluka kakhulu nge-morphology, usayizi wezinhlayiyana, nezindiza zekristalu eziveziwe, okuyizici ezibalulekile ezithinta ukusebenza nokusebenza kwazo.Ngokuvamile kunenkolelo yokuthi izinhlayiya ezincane kanye nendawo enkulu yendawo ethile, indawo esebenzayo ehambisanayo, futhi inamandla amandla okwenza i-catalytic.Ikhono le-catalytic yendawo yekristalu eveziwe, ukusuka kokuqinile kuye ebuthakathakeni, ilandelana (100) crystal surface>(110) crystal surface>(111) indawo eyikristalu, futhi ukuzinza okuhambisanayo kuphambene.
I-Cerium oxide iyimpahla ye-semiconductor.Uma i-nanometer cerium oxide ikhanyiswa ngama-photon anamandla aphezulu kunegebe lebhendi, ama-electron ebhendi ye-valence ayajabula, futhi ukuziphatha kokuguqulwa kabusha kwenzeka.Lokhu kuziphatha kuzothuthukisa izinga lokuguqulwa le-Ce3+ ne-Ce4+, okuholela emsebenzini oqinile we-photocatalytic we-nano ceria.I-Photocatalysis ingafinyelela ukucekelwa phansi okuqondile kwezinto eziphilayo ngaphandle kokungcoliswa kwesibili, ngakho-ke ukusetshenziswa kwayo ubuchwepheshe obufundwe kakhulu emkhakheni we-nano ceria kuma-AOP.Njengamanje, okugxilwe kakhulu ekwelapheni okubangela ukucekelwa phansi kodayi be-azo, i-phenol, i-chlorobenzene, namanzi angcolile ekhemisi kusetshenziswa ama-catalyst ane-morphology ehlukene kanye nezingoma eziyinhlanganisela.Ngokombiko, ngaphansi kwendlela ye-catalyst synthesis elungiselelwe kanye nezimo zemodeli ye-catalytic, umthamo wokuwohloka walezi zinto ngokuvamile ungafinyelela ngaphezu kwama-80%, futhi umthamo wokukhipha we-Total organic carbon (TOC) ungafinyelela ngaphezu kuka-40%.
I-Nano cerium oxide catalysis yokucekelwa phansi kwezinto ezingcolisa imvelo njenge-ozone ne-hydrogen peroxide ingobunye ubuchwepheshe obufundwe kabanzi.Ngokufanayo ne-photocatalysis, iphinde igxile ekhonweni le-nano ceria ene-morphology ehlukene noma izindiza zekristalu kanye nama-cerium asekelwe enhlanganisela ye-catalytic oxidants ehlukene ukuze i-oxidize futhi inciphise ukungcola kwemvelo.Ekuphenduleni okunjalo, ama-catalysts angakwazi ukuvuselela ukukhiqizwa kwenani elikhulu lama-radicals asebenzayo avela ku-ozone noma i-hydrogen peroxide, ahlasela ukungcola kwezinto eziphilayo futhi azuze amakhono asebenza ngempumelelo okuwohloka kwe-oxidative.Ngenxa yokwethulwa kwama-oxidants ekuphenduleni, amandla okususa ama-organic compounds athuthukiswa kakhulu.Ekuphenduleni okuningi, izinga lokugcina lokususwa kwento eqondiwe lingafinyelela noma lisondele ku-100%, futhi izinga lokususwa kwe-TOC nalo liphezulu.
Ngendlela ye-electrocatalytic advanced oxidation, izakhiwo ze-anode ene-oxygen evolution overpotential inquma ukukhetha kwendlela ye-electrocatalytic advanced oxidation yokwelapha ukungcola kwemvelo.Impahla ye-cathode iyisici esibalulekile esinquma ukukhiqizwa kwe-H2O2, futhi ukukhiqizwa kwe-H2O2 kunquma ukusebenza kahle kwendlela ye-electrocatalytic advanced oxidation yokwelapha ukungcola kwemvelo.Ucwaningo lokuguqulwa kwezinto zama-electrode kusetshenziswa i-nano ceria seluthole ukunakwa okusabalele ngaphakathi nangaphandle.Abacwaningi ikakhulukazi bethula i-nano cerium oxide nezinto zayo eziyinhlanganisela ngokusebenzisa izindlela zamakhemikhali ezihlukene ukuze baguqule izinto ezisetshenziswayo ze-electrode, bathuthukise umsebenzi wabo we-electrochemical, futhi ngaleyo ndlela bandise umsebenzi we-electrocatalytic kanye nenani lokugcina lokususa.
I-Microwave ne-ultrasound kuvame ukuba yizinyathelo ezibalulekile ezisizayo zamamodeli anamandla angenhla.Sithatha usizo lwe-ultrasonic njengesibonelo, kusetshenziswa amaza omsindo wokudlidliza anamaza angaphezulu kuka-25kHz ngomzuzwana, izigidi zamabhamuza amancane kakhulu akhiqizwa ngesisombululo esakhiwe nge-ejenti yokuhlanza eklanywe ngokukhethekile.Lawa mabhamuza amancane, phakathi nokucindezelwa okusheshayo nokunwetshwa, ahlala ekhiqiza i-bubble implosion, okuvumela izinto ukuthi zishintshane ngokushesha futhi zisakazeke endaweni ye-catalyst, ngokuvamile ethuthukisa ngokusobala ukusebenza kahle kwe-catalytic.
3 Isiphetho
I-Nano ceria nezinto zayo eziyinhlanganisela ingaphatha ngempumelelo ama-ion nokungcola kwemvelo emanzini, futhi ibe namandla okusebenza abalulekile ezinkundleni zokwelashwa kwamanzi ezizayo.Kodwa-ke, ucwaningo oluningi lusasesigabeni saselabhorethri, futhi ukuze kuzuzwe ukusetshenziswa ngokushesha ekuhlanzeni amanzi esikhathini esizayo, lezi zinkinga ezilandelayo zisadinga ukubhekwana nazo ngokushesha:
(1) Izindleko zokulungiselela eziphakeme kakhulu ze-nanoCeO2izinto ezisekelwe zihlala ziyisici esibalulekile eningini lezicelo zazo ekuhlanzeni amanzi, ezisesigabeni socwaningo lwaselabhorethri.Ukuhlola izindlela ezingabizi kakhulu, ezilula nezisebenzayo zokulungiselela ezingalawula i-morphology kanye nobukhulu bezinto ezisekelwe ku-nano CeO2 kusewumgomo wocwaningo.
(2) Ngenxa yosayizi wezinhlayiyana ezincane zezinto ezisekelwe ku-nano CeO2, izinkinga zokugaywa kabusha nokukhiqizwa kabusha ngemva kokusetshenziswa nazo ziyizici ezibalulekile ezikhawulela ukusetshenziswa kwazo.Inhlanganisela yayo ene-resin materials noma izinto kazibuthe kuzoba isiqondiso esibalulekile socwaningo ekulungiseni kwayo okubalulekile kanye nobuchwepheshe bokugaywa kabusha.
(3) Ukuthuthukiswa kwenqubo ehlanganyelwe phakathi kobuchwepheshe bokuhlanza amanzi okusekelwe ku-nano CeO2 kanye nobuchwepheshe bendabuko bokukhuculula indle kuzokhuthaza kakhulu ukusetshenziswa kobuchwepheshe obusekelwe ku-nano CeO2 emkhakheni wokuhlanza amanzi.
(4) Kusenocwaningo olulinganiselwe ngobuthi bezinto ezisekelwe ku-nano CeO2, futhi ukuziphatha kwazo kwendawo ezungezile kanye nezindlela ezinobuthi ezinhlelweni zokuhlanza amanzi akukanqunywa okwamanje.Inqubo yangempela yokuhlanza indle ngokuvamile ihilela ukuhlalisana kwezinto ezingcolisayo eziningi, futhi ukungcola okukhona kuzosebenzisana, ngaleyo ndlela kuguqule izici ezingaphezulu kanye nobuthi obungaba khona be-nanomaterials.Ngakho-ke, kunesidingo esiphuthumayo sokwenza ucwaningo olwengeziwe mayelana nezici ezihlobene.
Isikhathi sokuthumela: May-22-2023