CeO2bụ akụkụ dị mkpa nke ihe ndị dị ụkọ n'ụwa. Nkeobere ụwa element ceriumnwere ihe owuwu eletrọnịkị pụrụ iche - 4f15d16s2. Igwe oyi akwa 4f ya pụrụ iche nwere ike chekwaa ma hapụ electrons nke ọma, na-eme ka cerium ion na-akpa àgwà na steeti valence+3 na+4 valence steeti. Ya mere, ihe CeO2 nwere ọtụtụ oghere oxygen, ma nwee ikike magburu onwe ya ịchekwa ma hapụ oxygen. Ntughari ntughari nke Ce (III) na Ce (IV) na-enyekwa ihe CeO2 nwere ike oxidation-mbelata puru iche. Tụnyere nnukwu ihe, nano CeO2, dị ka ụdị ọhụrụ nke inorganic ihe onwunwe, enwetawo nlebara anya zuru ebe nile n'ihi na elu ya kpọmkwem n'elu ebe, magburu onwe oxygen nchekwa na ntọhapụ ikike, oxygen ion conductivity, redox arụmọrụ, na elu okpomọkụ ngwa ngwa ikuku oxygen mgbasa mgbasa. ike. Enwere ugbu a ọnụ ọgụgụ dị ukwuu nke akụkọ nyocha na ngwa ndị metụtara ya na-eji nano CeO2 dị ka ndị na-emepụta ihe, ndị na-ebu ma ọ bụ ihe mgbakwunye, ihe ndị na-arụ ọrụ, na adsorbents.
1. Usoro nkwadebe nke nanometercerium oxide
Ka ọ dị ugbu a, usoro nkwadebe a na-ahụkarị maka nano ceria gụnyere usoro kemịkalụ na usoro anụ ahụ. Dị ka usoro kemịkalụ dị iche iche si dị, a pụrụ ikewa ụzọ kemịkalụ n'ime usoro mmiri ozuzo, usoro hydrothermal, usoro solvothermal, usoro gel gel, usoro microemulsion na usoro electrodeposition; Usoro anụ ahụ bụ tumadi usoro egweri.
1.1 Usoro egweri
Usoro egweri maka ịkwadebe nano ceria n'ozuzu na-eji ájá egweri, nke nwere uru nke ọnụ ala dị ala, enyi gburugburu ebe obibi, ọsọ nhazi ngwa ngwa, na ike nhazi ike. Ọ bụ ugbu a usoro nhazi kachasị mkpa na ụlọ ọrụ nano ceria. Dịka ọmụmaatụ, nkwadebe nke nano cerium oxide polishing ntụ ntụ n'ozuzu na-anakọta ngwakọta nke calcination na ntụ ntụ, na akụrụngwa nke cerium dabeere denitration catalysts na-agwakọtakwa maka tupu ọgwụgwọ ma ọ bụ na-emeso mgbe calcination iji ájá egweri. Site na iji dị iche iche urughuru size ájá egweri bead ratios, nano ceria na D50 sitere na iri iri na narị nanometers nwere ike nweta site mmezi.
1.2 Usoro mmiri ozuzo
Usoro mmiri ozuzo na-ezo aka na usoro nke ịkwadebe ntụ ntụ siri ike site na mmiri ozuzo, nkewa, ịsacha, ihicha na calcination nke akụrụngwa agbazere na ihe mgbaze kwesịrị ekwesị. A na-eji usoro mmiri ozuzo eme ihe n'ọtụtụ ebe na nkwadebe nke ụwa na-adịghị ahụkebe na nanomaterials doped, nwere uru dị ka usoro nkwadebe dị mfe, ịrụ ọrụ dị elu na ọnụ ala. Ọ bụ usoro a na-ejikarị akwadebe nano ceria na ihe ndị mejupụtara ya na ụlọ ọrụ. Usoro a nwere ike ịkwadebe nano ceria dị iche iche morphology na urughuru nha site n'ịgbanwe okpomọkụ mmiri ozuzo, ntinye ihe onwunwe, uru pH, ọsọ mmiri ozuzo, ọsọ na-akpali akpali, template, wdg. Ụzọ ndị a na-emekarị na-adabere na ọdịda nke cerium ion site na amonia eme site na urea decomposition. na nkwadebe nke nano ceria microspheres na-achịkwa ion citrate. N'aka nke ọzọ, cerium ion nwere ike ịmalite site na OH - nke sitere na hydrolysis nke sodium citrate, wee tinye ya na calcined iji kwadebe flake dị ka nano ceria microspheres.
1.3 Hydrothermal na solvothermal ụzọ
Ụzọ abụọ a na-ezo aka na usoro nke ịkwadebe ngwaahịa site na oke okpomọkụ na nrụgide dị elu na okpomọkụ dị oke egwu na usoro mechiri emechi. Mgbe ihe mgbaze mmeghachi omume bụ mmiri, a na-akpọ ya usoro hydrothermal. N'otu aka ahụ, mgbe ihe mgbaze mmeghachi omume bụ ihe mgbaze organic, a na-akpọ ya usoro solvothermal. The synthesized nano ahụ nwere ịdị ọcha dị elu, mgbasa ozi ọma na ihe ndị edo edo, ọkachasị nano powders nwere ụdị dị iche iche ma ọ bụ ihu kristal pụrụ iche kpughere. Gbarie cerium chloride n'ime mmiri distilled, kpalite ma gbakwunye ngwọta sodium hydroxide. Meghachi omume hydrothermal na 170 ℃ maka awa 12 iji kwadebe cerium oxide nanorods nwere ụgbọ elu kristal ekpughere (111) na (110). Site n'ịgbanwe ọnọdụ mmeghachi omume, ọnụ ọgụgụ nke (110) kristal na ụgbọ elu kristal ekpughere nwere ike ịba ụba, na-eme ka ọrụ catalytic ha dịkwuo elu. Idozi ihe mgbaze mmeghachi omume na ligands elu nwekwara ike imepụta ahụ nano ceria nwere hydrophilicity pụrụ iche ma ọ bụ lipophilicity. Dịka ọmụmaatụ, ịgbakwụnye ion acetate na mpaghara mmiri nwere ike ịkwadebe monodisperse hydrophilic cerium oxide nanoparticles na mmiri. Site n'ịhọrọ ihe mgbaze na-abụghị polar na iwebata oleic acid dị ka ligand n'oge mmeghachi omume, monodisperse lipophilic ceria nanoparticles nwere ike kwadebere na ndị na-abụghị polar organic solvents. (Lee foto nke 1)
Ọgụgụ 1 Monodisperse spherical nano ceria na nano ceria nke yiri mkpanaka
1.4 Sol gel usoro
Usoro sol gel bụ usoro nke na-eji ụfọdụ ma ọ bụ ọtụtụ ogige dị ka ihe mbụ, na-eduzi mmeghachi omume kemịkalụ dị ka hydrolysis na mmiri mmiri na-emepụta sol, wee mepụta gel mgbe ịka nká, na n'ikpeazụ na-akpọnwụ na calcines iji kwadebe ntụ ntụ ultrafine. Usoro a dabara adaba nke ukwuu maka ịkwadebe nnukwu ihe nano ceria mejupụtara nanomaterials gbasasịrị agbasasị, dị ka cerium iron, cerium titanium, cerium zirconium na nano oxides ndị ọzọ mejupụtara, bụ nke akọworo n'ọtụtụ akụkọ.
1.5 Ụzọ ndị ọzọ
Na mgbakwunye na usoro ndị a dị n'elu, enwerekwa usoro micro lotion, usoro njikọ microwave, usoro electrodeposition, usoro ọkụ ọkụ plasma, usoro ion-exchange membrane electrolysis na ọtụtụ ụzọ ndị ọzọ. Ụzọ ndị a nwere nnukwu uru maka nyocha na ntinye nke nano ceria.
Ngwa nke cerium oxide 2-nanometer na ọgwụgwọ mmiri
Cerium bụ ihe kachasị ukwuu n'etiti ihe ndị dị n'ụwa na-adịghị ahụkebe, yana ọnụ ahịa dị ala na ngwa obosara. Nanometer ceria na ihe ndị mejupụtara ya adọtala mmasị dị ukwuu na mpaghara ọgwụgwọ mmiri n'ihi oke elu ha dị elu, ọrụ catalytic dị elu na nkwụsi ike nhazi dị mma.
2.1 Ngwa nkeNano cerium oxidena ọgwụgwọ mmiri site na Adsorption Method
N'ime afọ ndị na-adịbeghị anya, na mmepe nke ụlọ ọrụ dị ka ụlọ ọrụ eletriki, nnukwu mmiri na-ekpofu ihe nwere ihe ndị na-emerụ emerụ dị ka ion ion dị arọ na fluorine ion. Ọbụlagodi na nleba anya, ọ nwere ike imerụ ihe ndị dị n'ime mmiri na gburugburu ebe obibi mmadụ. Ụzọ ndị a na-ejikarị eme ihe gụnyere oxidation, flotation, reverse osmosis, adsorption, nanofiltration, biosorption, wdg. N'ime ha, a na-ejikarị teknụzụ mgbasa ozi na-anabata ya n'ihi ọrụ ya dị mfe, ọnụ ala, na ọgwụgwọ dị elu. Nano CeO2 ihe nwere elu kpọmkwem n'elu ebe na elu elu ọrụ dị ka adsorbents, na e nweela ọtụtụ akụkọ banyere njikọ nke porous nano CeO2 na ihe mejupụtara ya dị iche iche morphologies na adsorb na-ewepụ ions na-emerụ na mmiri.
Nnyocha egosiwo na nano ceria nwere ikike adsorption siri ike maka F - na mmiri n'okpuru ọnọdụ acid na-adịghị ike. Na ngwọta na ntinye uche mbụ nke F - nke 100mg / L na pH = 5-6, ikike mgbasa ozi maka F - bụ 23mg / g, na mwepụ nke F - bụ 85.6%. Mgbe etinyere ya na bọọlụ resin polyacrylic acid (ọnụọgụ ibu: 0.25g / g), ikike iwepụ F - nwere ike iru karịa 99% mgbe ị na-emeso nha nha nke 100mg / L nke F - ngwọta mmiri; Mgbe ị na-edozi 120 ugboro olu, ihe karịrị 90% F - nwere ike wepụ. Mgbe a na-eji phosphate na iodate eme ihe, ikike mgbasa ozi nwere ike iru karịa 100mg/g n'okpuru ọnọdụ mgbasa ozi kacha mma. Enwere ike iji ihe eji eme ihe mee ihe mgbe nkwụsịtụ dị mfe na ọgwụgwọ nkwụsịtụ, nke nwere uru akụ na ụba dị elu.
Enwere ọtụtụ ọmụmụ gbasara mgbasa na ọgwụgwọ nke ọla dị arọ na-egbu egbu dị ka arsenic, chromium, cadmium, na lead na-eji nano ceria na ihe ndị mejupụtara ya. PH kacha mma adsorption dị iche maka ion metal dị arọ nwere steeti valence dị iche iche. Dịka ọmụmaatụ, ọnọdụ alkaline na-adịghị ike na-anọpụ iche nwere ọnọdụ mgbasa ozi kachasị mma maka As (III), ebe a na-enweta ọnọdụ mgbasa ozi kachasị mma maka As (V) n'okpuru ọnọdụ acidic na-adịghị ike, ebe ikike mgbasa ozi nwere ike iru 110mg / g n'okpuru abụọ ahụ. ọnọdụ. N'ozuzu, njikọ kachasị mma nke nano ceria na ihe ndị mejupụtara ya nwere ike nweta ọkwa mgbasa ozi dị elu na ọnụego mwepụ maka ion metal dị arọ dị iche iche n'elu oke pH.
N'aka nke ọzọ, cerium oxide dabeere nanomaterials nwekwara pụtara ìhè arụmọrụ na adsorbing organics na mmiri mkpofu, dị ka acid oroma, rhodamine B, Congo red, wdg Dị ka ihe atụ, na ẹdude kọrọ ikpe, nano ceria porous spheres kwadebere site electrochemical ụzọ nwere elu. ikike adsorption na mwepụ nke organic agba, karịsịa na mwepụ nke Congo red, na ike adsorption nke 942.7mg / g na 60 nkeji.
2.2 Ngwa nke nano ceria na usoro oxidation dị elu
A na-atụ aro usoro oxidation dị elu (AOPs maka mkpụmkpụ) iji melite usoro ọgwụgwọ anhydrous dị ugbu a. Usoro oxidation dị elu, nke a makwaara dị ka nkà na ụzụ oxidation miri emi, bụ nke mmepụta nke hydroxyl radical (· OH), superoxide radical (· O2 -), singlet oxygen, wdg na ike oxidation ike. N'okpuru ọnọdụ mmeghachi omume nke okpomọkụ dị elu na nrụgide, ọkụ eletrik, ụda, ọkụ irradiation, catalyst, wdg Dị ka ụzọ dị iche iche nke ịmepụta free radicals na mmeghachi omume mmeghachi omume, ha nwere ike kewaa n'ime photochemical oxidation, catalytic wet oxidation, sonochemistry oxidation, ozone. oxidation, electrochemical oxidation, Fenton oxidation, wdg (lee foto 2).
Ọgụgụ 2 nhazi ọkwa na teknụzụ nke usoro oxidation dị elu
Nnọọ ceriabụ ihe na-akpali akpali nke a na-ejikarị na usoro oxidation dị elu. N'ihi ngbanwe ngwa ngwa n'etiti Ce3+ na Ce4+ yana mmetụta mbelata oxidation ngwa ngwa na-ebute site na mmịnye oxygen na ntọhapụ, nano ceria nwere ezigbo ikike. Mgbe ejiri ya dị ka onye na-akwalite nkwalite, ọ nwekwara ike melite ike na nkwụsi ike nke ọma. Mgbe a na-eji nano ceria na ihe ndị mejupụtara ya dị ka ihe na-akpali akpali, ihe ndị na-emepụta ihe na-adịgasị iche iche na morphology, nha nha, na ụgbọ elu crystal ekpughere, bụ isi ihe na-emetụta arụmọrụ na ngwa ha. A na-ekwenyekarị na ka obere ihe ndị ahụ na-ebuwanye ibu na mpaghara elu ahụ kpọmkwem, saịtị ahụ na-arụ ọrụ kwekọrọ na ya, na ike catalytic na-esiwanye ike. The catalytic ike nke kristal ekpuchiri elu, site na ike ruo na-adịghị ike, bụ n'usoro nke (100) crystal elu>(110) crystal elu>(111) crystal elu, na kwekọrọ ekwekọ na-emegide.
Cerium oxide bụ ihe semiconductor. Mgbe nanometer cerium oxide na-agbapụta site na foton nwere ike dị elu karịa ọdịiche nke band, electrons valence na-enwe obi ụtọ, na omume ngbanwe mgbanwe na-eme. Omume a ga-akwalite ọnụego mgbanwe nke Ce3+ na Ce4+, na-ebute ọrụ fotocatalytic siri ike nke nano ceria. Photocatalysis nwere ike nweta mbibi ozugbo nke ihe ndị dị ndụ na-enweghị mmetọ nke abụọ, yabụ ngwa ya bụ teknụzụ kacha mụọ na ngalaba nano ceria na AOPs. Ka ọ dị ugbu a, isi ihe a na-elekwasị anya bụ ọgwụgwọ mmebi nke catalytic nke azo, phenol, chlorobenzene, na mmiri mkpofu ọgwụ na-eji ihe ndị nwere ụdị ọdịdị dị iche iche na ihe mejupụtara. Dị ka akụkọ ahụ si kwuo, n'okpuru usoro nhazi nke kachasị mma na ọnọdụ ihe atụ catalytic, ikike mmebi nke ihe ndị a nwere ike iru karịa 80%, na ikike iwepụ Total organic carbon (TOC) nwere ike iru karịa 40%.
Nano cerium oxide catalysis maka mmebi nke ihe ndị na-emetọ ihe ndị dị ka ozone na hydrogen peroxide bụ nkà na ụzụ ọzọ a na-amụ n'ọtụtụ ebe. Dị ka fotocatalysis, ọ na-elekwasịkwa anya n'ikike nano ceria nwere ụdị ọdịdị dị iche iche ma ọ bụ ụgbọ elu kristal na cerium dị iche iche nke mejupụtara catalytic oxidants iji oxidize na mebie ihe ndị na-emerụ emerụ. N'ime mmeghachi omume ndị dị otú ahụ, ihe na-akpali akpali nwere ike ime ka ọgbọ nke ọnụ ọgụgụ dị ukwuu nke radicals na-arụ ọrụ site na ozone ma ọ bụ hydrogen peroxide, nke na-awakpo ihe ndị na-emerụ emerụ ma nweta ikike mmebi oxidative nke ọma. N'ihi iwebata oxidants na mmeghachi omume ahụ, a na-eme ka ikike iwepụ ihe ndị na-emepụta ihe na-eme ka ọ dịkwuo mma. N'ọtụtụ mmeghachi omume, ọnụego mwepụ ikpeazụ nke ihe ebumnuche nwere ike iru ma ọ bụ bịaruo 100%, ọnụego mwepụ TOC dịkwa elu.
N'ime usoro oxidation dị elu nke electrocatalytic, njirimara nke ihe anode nwere mgbanwe ikuku oxygen dị elu na-ekpebi nhọrọ nke usoro oxidation dị elu nke electrocatalytic maka ịgwọ mmetọ organic. The cathode ihe bụ ihe dị mkpa na-ekpebi mmepụta nke H2O2, na mmepụta nke H2O2 na-ekpebi irè nke electrocatalytic elu oxidation usoro maka ọgwụgwọ organic mmetọ. Ọmụmụ ihe ngbanwe ihe elektrọd site na iji nano ceria anatala nlebara anya zuru oke ma n'ime ụlọ na mba ụwa. Ndị na-eme nchọpụta na-ebutekarị nano cerium oxide na ihe ndị mejupụtara ya site na ụzọ kemịkalụ dị iche iche iji gbanwee ihe electrode dị iche iche, kwalite ọrụ electrochemical ha, wee si otú ahụ mụbaa ọrụ electrocatalytic na nkwụsị ikpeazụ.
Microwave na ultrasound na-abụkarị ihe enyemaka dị mkpa maka ụdị catalytic dị n'elu. Inweta enyemaka ultrasonic dị ka ihe atụ, na-eji ebili mmiri na-ama jijiji na ugboro dị elu karịa 25kHz kwa sekọnd, a na-emepụta ọtụtụ nde obere afụ na ngwọta nke ejiri ihe nhicha pụrụ iche emebere. Ndị a obere egosipụta, n'oge ngwa ngwa mkpakọ na mgbasawanye, mgbe niile na-emepụta afụ implosion, ikwe ka ihe ngwa ngwa mgbanwe na-agbasa n'elu catalyst elu, mgbe exponentially mma catalytic arụmọrụ.
3 Nkwubi okwu
Nano ceria na ihe ndị mejupụtara ya nwere ike ịgwọ ion na ihe ndị na-emetọ mmiri na mmiri nke ọma, ma nwee ikike ngwa dị mkpa na mpaghara ọgwụgwọ mmiri n'ọdịnihu. Otú ọ dị, ọtụtụ nnyocha ka na-na laabu ogbo, na iji nweta ngwa ngwa ngwa na mmiri ọgwụgwọ n'ọdịnihu, ndị na-esonụ okwu ka mkpa ka a ga-ngwa ngwa:
(1) The dịtụ elu nkwadebe na-eri nke nanoCeO2ihe ndị dabere na-anọgide na-abụ ihe dị mkpa n'ọtụtụ ngwa ngwa ha na ọgwụgwọ mmiri, nke ka nọ na nyocha nyocha ụlọ nyocha. Ịchọgharị ụzọ nkwadebe dị ọnụ ala, dị mfe ma dị irè nke nwere ike ịhazi morphology na nha nke nano CeO2 dabeere na ihe ndị a ka na-elekwasị anya nyocha.
(2) N'ihi na obere urughuru size nke nano CeO2 dabeere ihe, na recycling na regeneration okwu mgbe ojiji bụkwa ihe dị mkpa na-amachi ha ngwa. Ngwakọta ya na ihe resin ma ọ bụ ihe ndọta ga-abụ ntụzịaka nyocha maka nkwadebe ihe na teknụzụ imegharị ya.
(3) The mmepe nke a nkwonkwo usoro n'etiti nano CeO2 dabeere ihe mmiri ọgwụgwọ technology na omenala nsị ọgwụgwọ technology ga-ukwuu kwalite ngwa nke nano CeO2 dabeere ihe catalytic technology na ubi nke mmiri ọgwụgwọ.
(4) A ka nwere nyocha ole na ole banyere nsị nke nano CeO2 ihe ndị dabeere na ya, na omume gburugburu ebe obibi ha na usoro nsị na usoro ọgwụgwọ mmiri ekpebibeghị. Usoro ọgwụgwọ nsị mmiri n'ezie na-agụnyekarị ịdị n'otu nke ọtụtụ ihe ndị na-emetọ ihe, na ndị na-emetọ ihe na-emekọ ihe ga-emekọrịta ihe n'etiti ibe ha, si otú ahụ na-agbanwe àgwà elu na nsí nke nanomaterials. Ya mere, ọ dị mkpa ngwa ngwa ime nyocha ndị ọzọ gbasara akụkụ ndị metụtara ya.
Oge nzipu: Mee-22-2023