CeO2ndi gawo lofunika kwambiri la zinthu zosawerengeka zapadziko lapansi. Therare earth element ceriumili ndi mawonekedwe apadera akunja amagetsi - 4f15d16s2. Wosanjikiza wake wapadera wa 4f amatha kusunga ndikutulutsa ma electron, kupangitsa ma cerium ions kukhala mu +3 valence state ndi +4 valence state. Chifukwa chake, zida za CeO2 zili ndi mabowo ochulukirapo a okosijeni, ndipo zimatha kusunga ndikutulutsa mpweya. Kutembenuka kwapakati pa Ce (III) ndi Ce (IV) kumaperekanso zida za CeO2 zokhala ndi mphamvu zapadera zochepetsera okosijeni. Poyerekeza ndi zinthu zambiri, nano CeO2, monga mtundu watsopano wa zinthu zopanda chilengedwe, yalandira chidwi kwambiri chifukwa cha malo ake apamwamba kwambiri, kusungirako mpweya wabwino kwambiri komanso kutulutsa mphamvu, mpweya wa ion conductivity, ntchito ya redox, ndi kutentha kwapamwamba kwambiri kufalikira kwa mpweya wa oxygen. luso. Pakali pano pali malipoti ochuluka a kafukufuku ndi mapulogalamu okhudzana ndi kugwiritsa ntchito nano CeO2 monga chothandizira, zonyamulira zonyamula kapena zowonjezera, zigawo zogwira ntchito, ndi zotsatsa.
1. Kukonzekera njira ya nanometercerium oxide
Pakalipano, njira zokonzekera za nano ceria makamaka zimaphatikizapo njira ya mankhwala ndi njira ya thupi. Malinga ndi njira zosiyanasiyana zamakina, njira zamankhwala zimatha kugawidwa munjira yamvula, njira ya hydrothermal, njira ya solvothermal, njira ya sol gel, njira ya microemulsion ndi njira ya electrodeposition; Njira yakuthupi ndiyo makamaka njira yopera.
1.1 Njira yopera
Njira yopera pokonzekera nano ceria nthawi zambiri imagwiritsa ntchito kugaya mchenga, komwe kuli ndi ubwino wa mtengo wotsika, kusungira zachilengedwe, kuthamanga mofulumira, komanso kukwanitsa kukonza bwino. Pakalipano ndi njira yofunika kwambiri yopangira makina a nano ceria. Mwachitsanzo, yokonza nano cerium okusayidi kupukuta ufa zambiri utenga osakaniza calcination ndi mchenga akupera, ndi zopangira cerium zochokera denitration catalysts nawonso kusakaniza chisanadze mankhwala kapena mankhwala pambuyo calcination ntchito mchenga akupera. Pogwiritsa ntchito mikanda yosiyanasiyana ya tinthu tating'onoting'ono, nano ceria yokhala ndi D50 kuyambira makumi mpaka mazana a nanometer imatha kupezeka mwa kusintha.
1.2 Njira yamvula
Njira yamvula imatanthawuza njira yokonzekera ufa wolimba ndi mvula, kulekanitsa, kuchapa, kuyanika, ndi kuwerengera kwa zipangizo zomwe zimasungunuka muzitsulo zoyenera. Njira yamvula imagwiritsidwa ntchito kwambiri pokonzekera nthaka yosowa kwambiri komanso doped nanomaterials, zokhala ndi zabwino monga kukonzekera kosavuta, kuchita bwino kwambiri, komanso mtengo wotsika. Ndi njira yomwe imagwiritsidwa ntchito pokonzekera nano ceria ndi zida zake zophatikizika m'makampani. Njirayi ikhoza kukonzekera nano ceria ndi maonekedwe osiyanasiyana ndi kukula kwa tinthu posintha kutentha kwa mpweya, ndende ya zinthu, pH mtengo, kuthamanga kwa mpweya, kuthamanga, template, etc. Njira zodziwika bwino zimadalira mpweya wa cerium ions kuchokera ku ammonia wopangidwa ndi urea kuwonongeka, ndi kukonzekera kwa nano ceria microspheres kumayendetsedwa ndi citrate ions. Kapenanso, ayoni cerium akhoza precipitated ndi OH - kwaiye ku hydrolysis wa sodium citrate, ndiyeno incubated ndi calcined kukonzekera flake ngati nano ceria microspheres.
1.3 Njira za Hydrothermal ndi solvothermal
Njira ziwirizi zimatanthawuza njira yokonzekera mankhwala ndi kutentha kwapamwamba komanso kuthamanga kwapamwamba pa kutentha kwakukulu mu dongosolo lotsekedwa. Pamene zosungunulira zomwe zimachitika ndi madzi, zimatchedwa njira ya hydrothermal. Momwemonso, pamene zosungunulira zomwe zimapangidwira zimakhala zosungunulira, zimatchedwa njira ya solvothermal. Tinthu tating'onoting'ono ta nano timakhala ndi chiyero chachikulu, kubalalitsidwa kwabwino komanso tinthu tating'onoting'ono, makamaka ma nano ufa okhala ndi ma morphologies osiyanasiyana kapena mawonekedwe apadera a kristalo. Sungunulani cerium chloride m'madzi osungunuka, yambitsani ndikuwonjezera sodium hydroxide solution. React hydrothermal pa 170 ℃ kwa maola 12 kukonzekera cerium oxide nanorods zowululidwa (111) ndi (110) ndege zamakristalo. Posintha momwe amachitira, gawo la (110) ndege zamakristali mu ndege zowululidwa za kristalo zitha kuonjezedwa, kupititsa patsogolo ntchito yawo yothandizira. Kusintha zimene zosungunulira ndi pamwamba ligands kungachititsenso nano ceria particles ndi hydrophilicity wapadera kapena lipophilicity. Mwachitsanzo, kuwonjezera ayoni acetate kwa gawo amadzimadzi akhoza kukonzekera monodisperse hydrophilic cerium okusayidi nanoparticles m'madzi. Posankha zosungunulira zosagwirizana ndi polar ndikuyambitsa oleic acid ngati ligand panthawiyi, monodisperse lipophilic ceria nanoparticles akhoza kukonzedwa muzosungunulira zopanda polar. (Onani chithunzi 1)
Chithunzi 1 Monodisperse spherical nano ceria ndi nano ceria yooneka ngati ndodo
1.4 Njira ya Sol gel
Njira ya sol gel ndi njira yomwe imagwiritsa ntchito mankhwala ena kapena angapo monga ma precursors, imapanga zochitika za mankhwala monga hydrolysis mu gawo lamadzimadzi kupanga sol, ndiyeno imapanga gel osakaniza pambuyo pa ukalamba, ndipo potsiriza imawuma ndi calcines kukonzekera ufa wochuluka kwambiri. Njirayi ndi yabwino kwambiri pokonzekera omwazika kwambiri amitundu yambiri ya nano ceria composite nanomaterials, monga chitsulo cha cerium, cerium titaniyamu, cerium zirconium ndi ma nano oxides ena ophatikizika, omwe adanenedwa m'ma report ambiri.
1.5 Njira zina
Kuphatikiza pa njira zomwe tafotokozazi, palinso njira ya micro lotion, njira yopangira ma microwave, njira ya electrodeposition, njira yoyaka moto ya plasma, njira ya electrolysis ya ion-exchange membrane electrolysis ndi njira zina zambiri. Njirazi zili ndi tanthauzo lalikulu pakufufuza ndi kugwiritsa ntchito nano ceria.
Kugwiritsa ntchito 2-nanometer cerium oxide pochiza madzi
Cerium ndiye chinthu chochuluka kwambiri pakati pa zinthu zosowa padziko lapansi, zotsika mtengo komanso zogwiritsidwa ntchito mosiyanasiyana. Nanometer ceria ndi ma composites ake akopa chidwi kwambiri pazamankhwala amadzi chifukwa cha malo awo apamwamba kwambiri, zochitika zazikulu zothandizira komanso kukhazikika kwadongosolo.
2.1 Kugwiritsa ntchito kwaNano Cerium oxidemu Chithandizo cha Madzi ndi Adsorption Method
M'zaka zaposachedwa, ndi chitukuko cha mafakitale monga mafakitale a zamagetsi, madzi ambiri otayira omwe ali ndi zonyansa monga zitsulo zolemera kwambiri ndi fluorine ions zatulutsidwa. Ngakhale pakuwunika, zitha kuwononga kwambiri zamoyo zam'madzi komanso malo okhala anthu. Njira zomwe zimagwiritsidwa ntchito nthawi zambiri zimaphatikizapo okosijeni, kuyandama, reverse osmosis, adsorption, nanofiltration, biosorption, etc. Pakati pawo, teknoloji ya adsorption nthawi zambiri imatengedwa chifukwa cha ntchito yake yosavuta, yotsika mtengo, komanso chithandizo chamankhwala. Zida za Nano CeO2 zili ndi malo apamwamba kwambiri komanso ntchito zapamwamba ngati zotsatsa, ndipo pakhala pali malipoti ambiri okhudzana ndi kaphatikizidwe ka porous nano CeO2 ndi zida zake zophatikizika zomwe zimakhala ndi ma morphologies osiyanasiyana kuti zikongoletsere ndikuchotsa ma ion owopsa m'madzi.
Kafukufuku wasonyeza kuti nano ceria ali wamphamvu adsorption mphamvu F - m'madzi pansi ofooka acidic mikhalidwe. Mu njira yothetsera ndende yoyamba ya F - ya 100mg / L ndi pH = 5-6, mphamvu ya adsorption ya F - ndi 23mg / g, ndipo mlingo wochotsa F - ndi 85.6%. Pambuyo poyikira pa polyacrylic acid resin mpira (kutsitsa kuchuluka: 0.25g/g), kuthekera kochotsa kwa F - kumatha kufika pa 99% pochiza voliyumu yofanana ya 100mg/L ya F - yankho lamadzi; Pokonza 120 nthawi voliyumu, oposa 90% a F - akhoza kuchotsedwa. Mukagwiritsidwa ntchito kutsatsa phosphate ndi iodate, mphamvu ya adsorption imatha kufika pa 100mg/g pansi pamlingo wofananira nawo wa adsorption. Zomwe zimagwiritsidwa ntchito zimatha kugwiritsidwanso ntchito pambuyo pa chithandizo chosavuta cha desorption ndi neutralization, chomwe chili ndi phindu lalikulu lazachuma.
Pali maphunziro ambiri okhudzana ndi kutsatsa ndi kuchiza zitsulo zolemera zapoizoni monga arsenic, chromium, cadmium, ndi lead pogwiritsa ntchito nano ceria ndi zida zake zophatikizika. Mulingo woyenera kwambiri wa adsorption pH umasiyanasiyana ma ayoni azitsulo zolemera okhala ndi mayiko osiyanasiyana a valence. Mwachitsanzo, mkhalidwe wofooka wa alkaline wokhala ndi tsankho losalowerera ndale umakhala ndi malo abwino kwambiri opangira As (III), pomwe malo abwino kwambiri a adsorption a As (V) amakwaniritsidwa pansi pa mikhalidwe yofooka ya acidic, pomwe mphamvu ya adsorption imatha kufikira 110mg/g pansi pa zonse ziwiri. mikhalidwe. Ponseponse, kaphatikizidwe kokometsedwa kwa nano ceria ndi zida zake zophatikizika zimatha kukwaniritsa kutsatsa kwakukulu ndikuchotsa ma ion azitsulo zolemera zosiyanasiyana pa pH yotakata.
Komano, cerium okusayidi zochokera nanomaterials amakhalanso ndi ntchito kwambiri adsorbing organic mu madzi oipa, monga asidi lalanje, rhodamine B, Congo wofiira, etc. Kuthekera kwa adsorption pakuchotsa utoto wachilengedwe, makamaka pakuchotsa kofiyira ku Congo, ndi mphamvu ya adsorption 942.7mg/g mu mphindi 60.
2.2 Kugwiritsa ntchito nano ceria mu Advanced oxidation process
Advanced oxidation process (AOPs mwachidule) ikuganiziridwa kuti ipititse patsogolo njira yamankhwala yomwe ilipo ya anhydrous. MwaukadauloZida makutidwe ndi okosijeni ndondomeko, amatchedwanso kwambiri makutidwe ndi okosijeni luso, yodziwika ndi kupanga hydroxyl kwakukulukulu (· OH), superoxide kwakukulukulu (· O2 -), singlet mpweya, etc. ndi amphamvu makutidwe ndi okosijeni luso. Pansi zimene zikhalidwe za kutentha ndi kuthamanga, magetsi, phokoso, kuwala walitsa, chothandizira, etc. Malinga ndi njira zosiyanasiyana zopangira free radicals ndi zinthu anachita, iwo akhoza kugawidwa mu photochemical makutidwe ndi okosijeni, chothandizira chonyowa makutidwe ndi okosijeni, sonochemistry makutidwe ndi okosijeni, ozoni. oxidation, electrochemical oxidation, Fenton oxidation, etc. (onani Chithunzi 2).
Chithunzi 2 Classification and Technology Combination of Advanced oxidation process
Nano ceriandi heterogeneous chothandizira chomwe chimagwiritsidwa ntchito kwambiri mu Advanced oxidation process. Chifukwa cha kutembenuka mwachangu pakati pa Ce3+ ndi Ce4+ komanso kuchepa kwa okosijeni mwachangu komwe kumabwera chifukwa cha kuyamwa kwa okosijeni ndi kumasulidwa, nano ceria ili ndi kuthekera kwabwino kothandizira. Ikagwiritsidwa ntchito ngati chothandizira chothandizira, imathanso kukulitsa luso lothandizira komanso kukhazikika. Pamene nano ceria ndi zipangizo zake zogwiritsidwa ntchito zimagwiritsidwa ntchito monga zopangira, zopangira zothandizira zimasiyana kwambiri ndi morphology, kukula kwa tinthu, ndi ndege zowonekera za kristalo, zomwe ndizofunikira kwambiri zomwe zimakhudza ntchito ndi ntchito zawo. Ambiri amakhulupirira kuti ang'onoang'ono particles ndi yaikulu yeniyeni pamwamba m'dera, kwambiri lolingana yogwira malo, ndi mphamvu catalytic luso. Kuthekera kochititsa chidwi kwa kristalo wowonekera, kuyambira wamphamvu mpaka kufooka, ndi dongosolo la (100) kristalo pamwamba> (110) kristalo pamwamba> (111) pamwamba pa kristalo, ndipo kukhazikika kofanana ndi kosiyana.
Cerium oxide ndi zinthu za semiconductor. Pamene nanometer cerium oxide imawunikiridwa ndi ma photon okhala ndi mphamvu zapamwamba kuposa kusiyana kwa gulu, ma elekitironi a valence band amasangalala, ndipo kusintha kwakusinthanso kumachitika. Khalidweli lilimbikitsa kutembenuka kwa Ce3+ ndi Ce4+, zomwe zimapangitsa kuti pakhale zochitika zamphamvu za nano ceria. Photocatalysis imatha kuwononga mwachindunji zinthu zachilengedwe popanda kuipitsidwa kwachiwiri, chifukwa chake kugwiritsa ntchito kwake ndiukadaulo wophunziridwa kwambiri pamunda wa nano ceria mu AOPs. Pakadali pano, cholinga chachikulu ndikuthandizira kuwononga utoto wa azo utoto, phenol, chlorobenzene, ndi madzi otayira amankhwala omwe amagwiritsa ntchito zopangira zokhala ndi ma morphologies osiyanasiyana komanso nyimbo zophatikizika. Malinga ndi lipotilo, pansi pa njira yolimbikitsira kaphatikizidwe kaphatikizidwe ndi machitidwe othandizira, mphamvu zowonongeka za zinthuzi zimatha kufika kupitirira 80%, ndipo mphamvu yochotsa kwa Total organic carbon (TOC) imatha kufika kupitirira 40%.
Nano cerium oxide catalysis pakuwonongeka kwa zowononga organic monga ozoni ndi hydrogen peroxide ndiukadaulo wina womwe umaphunziridwa kwambiri. Mofanana ndi photocatalysis, imayang'ananso mphamvu ya nano ceria yokhala ndi ma morphologies osiyanasiyana kapena ndege za crystal ndi ma cerium-based composite catalytic oxidants kuti oxidize ndi kuwononga zowononga zachilengedwe. Muzochitika zotere, zothandizira zimatha kuyambitsa m'badwo wamitundu yambiri yochokera ku ozone kapena hydrogen peroxide, yomwe imalimbana ndi zoipitsa za organic ndikukhala ndi mphamvu zowononga kwambiri za okosijeni. Chifukwa cha kuyambika kwa okosijeni mu zomwe zimachitika, kuthekera kochotsa ma organic compounds kumakulitsidwa kwambiri. Nthawi zambiri, kuchotsera komaliza kwa chinthu chomwe mukufuna kutsitsa kumatha kufika kapena kuyandikira 100%, komanso kuchotsera kwa TOC ndikokweranso.
Mu njira ya electrocatalytic advanced oxidation, katundu wa anode okhala ndi kusinthika kwa okosijeni wapamwamba kwambiri amatsimikizira kusankha kwa njira ya electrocatalytic advanced oxidation pochiza zowononga zachilengedwe. Zinthu za cathode ndizofunikira kwambiri pozindikira kupanga kwa H2O2, ndipo kupanga kwa H2O2 kumatsimikizira mphamvu ya njira ya electrocatalytic advanced oxidation pochiza zowononga zachilengedwe. Kafukufuku wokhudza kusintha kwa ma elekitirodi pogwiritsa ntchito nano ceria walandira chidwi chofala padziko lonse lapansi komanso padziko lonse lapansi. Ofufuza makamaka amayambitsa nano cerium oxide ndi zida zake zophatikizika kudzera m'njira zosiyanasiyana zama mankhwala kuti asinthe zinthu zosiyanasiyana zama elekitirodi, kupititsa patsogolo ntchito zawo zama electrochemical, motero amawonjezera zochitika za electrocatalytic komanso kuchotsera komaliza.
Microwave ndi ultrasound nthawi zambiri ndizofunikira zothandizira pazitsanzo zapamwambazi. Kutengera thandizo la akupanga mwachitsanzo, pogwiritsa ntchito mafunde akunjenjemera okhala ndi mafunde apamwamba kuposa 25kHz pamphindikati, tinthu tating'onoting'ono tambirimbiri timapangidwa munjira yopangidwa ndi chipangizo choyeretsera mwapadera. Tinthu ting'onoting'ono timeneti, panthawi ya kukanikizana kofulumira ndi kukulitsa, nthawi zonse kumatulutsa kuphulika kwa buluu, kulola kuti zipangizo zisinthe mofulumira ndi kufalikira pa chothandizira pamwamba, nthawi zambiri zimathandizira kuti zitheke.
3 Mapeto
Nano ceria ndi zida zake zophatikizika zimatha kuthana ndi ayoni ndi zowononga zachilengedwe m'madzi, komanso kukhala ndi kuthekera kofunikira m'malo opangira madzi am'tsogolo. Komabe, kafukufuku wambiri akadali mu labotale, ndipo kuti akwaniritse ntchito yochizira madzi m'tsogolomu, zinthu zotsatirazi ziyenera kuthetsedwa mwachangu:
(1) Mtengo wokwanira wokonzekera nanoCeO2zipangizo zochokera akadali chinthu chofunika kwambiri ambiri ntchito zawo mu mankhwala madzi, amene akadali mu zasayansi siteji kafukufuku. Kufufuza njira zotsika mtengo, zosavuta komanso zogwira mtima zokonzekera zomwe zingathe kulamulira morphology ndi kukula kwa zipangizo za nano CeO2 zidakali zofufuza.
(2) Chifukwa cha kukula kwa tinthu tating'ono ta nano CeO2, zobwezerezedwanso ndi kusinthika pambuyo pakugwiritsa ntchito ndizofunikiranso zomwe zimalepheretsa kugwiritsa ntchito kwawo. Chophatikizika chake chokhala ndi utomoni kapena zida zamaginito chikhala njira yayikulu yofufuzira pakukonzekera kwake komanso ukadaulo wobwezeretsanso.
(3) Kupanga njira yolumikizirana pakati pa ukadaulo wa nano CeO2 wotengera zinthu zamadzimadzi komanso ukadaulo wazimbudzi wachikhalidwe udzalimbikitsa kwambiri kugwiritsa ntchito ukadaulo wa nano CeO2 pothandizira ukadaulo wamadzi.
(4) Pakadalibe kafukufuku wochepa wokhudzana ndi kawopsedwe wa zida za nano CeO2, ndipo machitidwe awo azachilengedwe ndi kawopsedwe kawo m'machitidwe ochizira madzi sizinadziwikebe. Njira yeniyeni yochotsera zimbudzi nthawi zambiri imaphatikizapo kukhalapo kwa zowononga zambiri, ndipo zowonongeka zomwe zimakhalapo zimagwirizanitsa wina ndi mzake, motero kusintha mawonekedwe a pamwamba ndi poizoni wa nanomaterials. Chifukwa chake, pakufunika mwachangu kufufuza kowonjezereka pazinthu zofananira.
Nthawi yotumiza: May-22-2023