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Qhia ib lub carousel ntawm peb slides ib zaug.Siv cov nyees khawm dhau los thiab Tom ntej kom txav mus los ntawm peb qhov swb ib zaug, lossis siv cov khawm slider thaum kawg kom txav mus los ntawm peb qhov swb ib zaug.
Lub hav zoov ntawm cov hlau emissions los ntawm microwave hluav taws xob muaj teeb meem vim hais tias hlau ignite yooj yim.Tab sis dab tsi yog qhov nthuav yog tias cov kws tshawb fawb pom tias qhov tshwm sim ntawm arc tawm muaj txoj hauv kev zoo rau kev sib txuas ntawm nanomaterials los ntawm kev faib cov molecules.Txoj kev tshawb no tab tom tsim ib kauj ruam tseem tsis tau muaj txiaj ntsig zoo hluavtaws uas sib xyaw ua ke microwave cua sov thiab hluav taws xob arc los hloov cov roj xibtes roj rau hauv cov hlau nplaum nanocarbon (MNC), uas tuaj yeem suav tias yog lwm txoj hauv kev tshiab rau cov roj txiv ntoo.Nws koom nrog kev sib txuas ntawm qhov nruab nrab nrog rau qhov mob mus tas li stainless hlau xaim (dielectric nruab nrab) thiab ferrocene (catalyst) nyob rau hauv qee qhov tsis zoo.Txoj kev no tau ua tiav pom zoo rau cov cua sov hauv qhov kub ntawm 190.9 txog 472.0 ° C nrog ntau lub sijhawm sib xyaw (10-20 min).Freshly npaj MNCs pom spheres nrog qhov nruab nrab qhov loj ntawm 20.38–31.04 nm, mesoporous qauv (SBET: 14.83–151.95 m2 / g) thiab cov ntsiab lus siab ntawm cov pa roj carbon monoxide (52.79–71.24 wt.%), nrog rau D thiab G. pawg (ID/g) 0.98–0.99.Kev tsim cov ncov tshiab hauv FTIR spectrum (522.29–588.48 cm–1) ua pov thawj pom zoo ntawm FeO cov tebchaw hauv ferrocene.Magnetometers qhia siab magnetization saturation (22.32–26.84 emu/g) hauv cov ntaub ntawv ferromagnetic.Kev siv MNCs hauv kev kho dej khib nyiab tau ua pov thawj los ntawm kev ntsuas lawv cov peev txheej adsorption siv methylene blue (MB) adsorption test ntawm ntau qhov ntau ntawm 5 txog 20 ppm.MNCs tau txais ntawm lub sijhawm sib txuas (20 min) tau pom qhov ua tau zoo tshaj plaws adsorption (10.36 mg / g) piv rau lwm tus, thiab MB dye tshem tawm tus nqi yog 87.79%.Yog li ntawd, Langmuir qhov tseem ceeb tsis zoo li piv rau Freundlich qhov tseem ceeb, nrog R2 yog li ntawm 0.80, 0.98 thiab 0.99 rau MNCs synthesized ntawm 10 min (MNC10), 15 min (MNC15) thiab 20 min (MNC20) raws li.Yog li ntawd, lub adsorption system yog nyob rau hauv ib tug heterogeneous xeev.Yog li, microwave arcing muaj txoj kev cog lus rau kev hloov CPO rau MNC, uas tuaj yeem tshem tawm cov xim tsis zoo.
Microwave hluav taws xob tuaj yeem ua kom sov rau sab hauv ntawm cov ntaub ntawv los ntawm kev sib cuam tshuam molecular ntawm electromagnetic teb.Qhov no microwave teb yog tshwj xeeb nyob rau hauv uas nws txhawb ib tug ceev thiab zoo thermal teb.Yog li, nws muaj peev xwm ua kom cov txheej txheem cua sov thiab txhim kho cov tshuaj tiv thaiv 2.Nyob rau tib lub sijhawm, vim lub sijhawm luv luv, cov tshuaj tiv thaiv microwave tuaj yeem tsim cov khoom ntawm cov purity siab thiab siab yield3,4.Vim nws cov khoom zoo kawg nkaus, microwave hluav taws xob pab txhawb kev nthuav dav microwave syntheses uas yog siv rau hauv ntau cov kev tshawb fawb, nrog rau cov tshuaj tiv thaiv thiab cov synthesis ntawm nanomaterials5,6.Thaum lub sij hawm cov txheej txheem cua sov, lub dielectric zog ntawm tus neeg txais nyob rau hauv nruab nrab plays lub luag hauj lwm txiav txim siab, vim nws tsim ib tug kub qhov chaw nyob rau hauv nruab nrab, uas ua rau lub tsim ntawm nanocarbons nrog txawv morphologies thiab cov khoom.Kev tshawb fawb los ntawm Omoriyekomwan et al.Kev tsim cov hollow carbon nanofibers los ntawm xibtes kernels siv activated carbon thiab nitrogen8.Tsis tas li ntawd, Fu thiab Hamid txiav txim siab siv lub catalyst rau kev tsim cov roj xibtes fiber ntau cov pa roj carbon monoxide hauv 350 W9 microwave qhov cub.Yog li ntawd, ib txoj hauv kev zoo sib xws tuaj yeem siv los hloov cov roj txiv maj phaub rau MNCs los ntawm kev qhia cov khoom pov tseg uas tsim nyog.
Ib qho tshwm sim nthuav tau pom ntawm microwave hluav taws xob thiab hlau nrog cov npoo ntse, dots lossis submicroscopic irregularities10.Lub xub ntiag ntawm ob yam khoom no yuav raug cuam tshuam los ntawm hluav taws xob arc lossis spark (feem ntau hu ua arc tawm) 11,12.Lub arc yuav txhawb kev tsim ntawm ntau qhov chaw kub kub thiab cuam tshuam cov tshuaj tiv thaiv, yog li txhim kho cov tshuaj muaj pes tsawg leeg ntawm ib puag ncig13.Qhov tshwj xeeb thiab nthuav tshwm sim no tau nyiam ntau yam kev tshawb fawb xws li kev tshem tawm cov kab mob sib kis 14,15, biomass tar cracking16, microwave pab pyrolysis17,18 thiab cov khoom siv hluavtaws 19,20,21.
Tsis ntev los no, nanocarbons xws li carbon nanotubes, carbon nanospheres, thiab hloov kho txo graphene oxide tau nyiam cov xim vim lawv cov khoom.Cov nanocarbons no muaj peev xwm ua tau zoo rau cov ntawv thov xws li kev tsim hluav taws xob mus rau kev ua kom huv dej los yog decontamination23.Tsis tas li ntawd, yuav tsum muaj cov khoom zoo carbon zoo, tab sis tib lub sijhawm, cov khoom sib nqus zoo yuav tsum muaj.Qhov no yog qhov muaj txiaj ntsig zoo rau kev siv ntau yam suav nrog kev ua haujlwm siab ntawm cov hlau ions thiab dyes hauv kev kho cov dej khib nyiab, cov khoom siv sib nqus hauv biofuels thiab txawm tias muaj kev ua haujlwm siab microwave absorbers24,25,26,27,28.Nyob rau tib lub sijhawm, cov pa roj carbon monoxide no muaj lwm qhov zoo dua, suav nrog kev nce hauv thaj tsam ntawm tus qauv qhov chaw ua haujlwm.
Nyob rau hauv xyoo tas los no, kev tshawb fawb rau cov khoom siv hlau nplaum nanocarbon tau nce.Feem ntau, cov hlau nplaum nanocarbons no yog cov khoom siv ntau yam uas muaj nanosized magnetic cov ntaub ntawv uas tuaj yeem ua rau sab nraud catalysts los ua, xws li sab nraud electrostatic lossis alternating magnetic fields29.Vim lawv cov khoom sib nqus, cov hlau nplaum nanocarbons tuaj yeem ua ke nrog ntau yam khoom xyaw thiab cov txheej txheem nyuaj rau immobilization30.Lub caij no, sib nqus nanocarbons (MNCs) qhia tau zoo heev hauv adsorbing pollutants los ntawm aqueous daws.Tsis tas li ntawd, qhov siab tshwj xeeb ntawm thaj chaw thiab qhov pores tsim hauv MNCs tuaj yeem ua kom muaj peev xwm adsorption31.Sib nqus sib cais tuaj yeem cais MNCs los ntawm cov kev daws teeb meem zoo heev, tig lawv mus rau hauv cov khoom siv tau thiab tswj tau sorbent32.
Ntau tus kws tshawb fawb tau pom tias cov khoom zoo nanocarbons tuaj yeem tsim tau siv cov roj txiv roj nyoos33,34.Xibtes roj, kev tshawb fawb hu ua Elais Guneensis, yog suav tias yog ib qho tseem ceeb ntawm cov roj uas tau siv tau nrog kev tsim tawm ntawm thaj tsam 76.55 lab tons hauv 202135. Cov roj txiv roj roj lossis CPO muaj qhov sib npaug ntawm cov roj tsis muaj roj (EFAs) thiab cov roj saturated fatty acids. (Singapore Monetary Authority).Feem ntau ntawm cov hydrocarbons hauv CPO yog triglycerides, glyceride muaj peb triglyceride acetate Cheebtsam thiab ib qho glycerol tivthaiv36.Cov hydrocarbons no tuaj yeem nthuav dav vim lawv cov ntsiab lus carbon loj, ua rau lawv muaj peev xwm ntsuab precursors rau nanocarbon ntau lawm37.Raws li cov ntaub ntawv, CNT37,38,39,40, carbon nanospheres33,41 thiab graphene34,42,43 feem ntau yog synthesized siv cov roj xibtes crude los yog edible roj.Cov nanocarbons no muaj peev xwm ua tau zoo hauv kev siv xws li kev tsim hluav taws xob mus rau kev ua kom huv dej los yog decontamination.
Thermal synthesis xws li CVD38 lossis pyrolysis33 tau dhau los ua txoj hauv kev zoo rau kev decomposition ntawm xibtes roj.Hmoov tsis zoo, qhov kub thiab txias hauv cov txheej txheem ua rau tus nqi ntau lawm.Kev tsim cov khoom uas nyiam 44 yuav tsum tau ua kom ntev, tedious txheej txheem thiab kev tu.Txawm li cas los xij, qhov xav tau rau kev sib cais ntawm lub cev thiab kev tawg yog qhov tsis lees paub vim qhov kev ruaj ntseg zoo ntawm cov roj xibtes roj ntawm qhov kub siab 45.Yog li ntawd, qhov kub siab dua tseem yuav tsum tau hloov cov roj txiv roj rau hauv cov ntaub ntawv carbonaceous.Cov kua arc tuaj yeem suav tias yog qhov muaj peev xwm zoo tshaj plaws thiab cov qauv tshiab rau kev sib nqus ntawm nanocarbon 46 .Txoj hauv kev no muab lub zog ncaj qha rau cov neeg ua ntej thiab cov kev daws teeb meem hauv cov xeev zoo siab heev.Ib qho arc tso tawm tuaj yeem ua rau cov pa roj carbon monoxide hauv cov roj txiv ntoo tawg.Txawm li cas los xij, qhov sib nrug ntawm electrode siv yuav tsum tau ua kom tau raws li qhov yuav tsum tau ua kom nruj, uas yuav txwv tsis pub muaj kev lag luam, yog li txoj kev siv tau zoo tseem yuav tsum tau tsim.
Rau qhov zoo tshaj plaws ntawm peb cov kev paub, kev tshawb fawb ntawm arc tawm siv microwaves raws li ib txoj hauv kev rau kev sib xyaw nanocarbons yog txwv.Nyob rau tib lub sijhawm, kev siv cov txiv maj phaub roj ua ntej tsis tau tshawb pom tag nrho.Yog li, txoj kev tshawb no tsom mus tshawb nrhiav qhov ua tau ntawm kev tsim cov hlau nplaum nanocarbons los ntawm cov txiv maj phaub roj ua ntej siv lub tshuab hluav taws xob siv lub qhov cub microwave.Kev nplua nuj ntawm cov roj txiv ntoo yuav tsum tau xav txog hauv cov khoom tshiab thiab kev siv.Txoj hauv kev tshiab no rau kev kho cov roj txiv ntoo tuaj yeem pab txhawb kev lag luam thiab yog lwm qhov nyiaj tau los rau cov neeg tsim cov roj xibtes, tshwj xeeb tshaj yog cuam tshuam rau cov neeg ua liaj ua teb me me cov roj txiv ntoo.Raws li kev tshawb fawb ntawm African cov tswv lag luam me los ntawm Ayompe li al., cov tswv lag luam me tsuas yog khwv tau nyiaj ntau dua yog tias lawv ua cov txiv hmab txiv ntoo tshiab lawv tus kheej thiab muag cov txiv maj phaub roj tsis yog muag rau cov neeg nruab nrab, uas yog ib txoj hauj lwm kim thiab tedious47.Nyob rau tib lub sijhawm, kev nce hauv lub Hoobkas kaw vim COVID-19 tau cuam tshuam rau cov khoom siv roj-raws li cov ntawv thov.Interestingly, vim hais tias feem ntau cov tsev neeg muaj kev nkag tau mus rau microwave qhov cub thiab cov txheej txheem tau npaj nyob rau hauv txoj kev tshawb no yuav xam tau tias yog ua tau thiab pheej yig, MNC ntau lawm yuav muab xam raws li ib tug lwm txoj rau me me-scale xibtes cog.Lub caij no, ntawm qhov loj dua, cov tuam txhab tuaj yeem nqis peev hauv cov reactors loj los tsim TNCs loj.
Txoj kev tshawb no tsuas yog hais txog cov txheej txheem synthesis siv stainless hlau ua lub dielectric nruab nrab rau ntau lub sijhawm.Cov kev tshawb fawb dav dav feem ntau siv microwaves thiab nanocarbons qhia txog lub sijhawm siv tau ntawm 30 feeb lossis ntau dua 33,34.Txhawm rau txhawb nqa lub tswv yim siv tau thiab ua tau, qhov kev tshawb fawb no tsom kom tau txais MNCs nrog qis dua qhov nruab nrab ntawm lub sijhawm sib xyaw.Nyob rau tib lub sijhawm, txoj kev tshawb no pleev xim rau daim duab ntawm kev npaj thev naus laus zis qib 3 raws li qhov kev xav tau raug pov thawj thiab siv rau hauv chav kuaj ntsuas.Tom qab ntawd, MNCs tau tshwm sim los ntawm lawv lub cev, tshuaj, thiab cov khoom sib nqus.Methylene xiav tau siv los ua kom pom lub peev xwm adsorption ntawm MNCs.
Crude xibtes tau txais los ntawm Apas Balung Mill, Sawit Kinabalu Sdn.Bhd., Tawau, thiab yog siv los ua carbon precursor rau synthesis.Nyob rau hauv cov ntaub ntawv no, ib tug stainless hlau hlau nrog ib txoj kab uas hla ntawm 0.90 mm yog siv raws li ib tug dielectric nruab nrab.Ferrocene (purity 99%), tau txais los ntawm Sigma-Aldrich, Tebchaws Asmeskas, tau raug xaiv los ua tus catalyst hauv txoj haujlwm no.Methylene xiav (Bendosen, 100 g) tau ntxiv rau kev sim adsorption.
Hauv txoj kev tshawb no, lub qhov cub microwave hauv tsev (Panasonic: SAM-MG23K3513GK) tau hloov mus rau hauv microwave reactor.Peb qhov tau ua nyob rau sab sauv ntawm lub qhov cub microwave rau qhov nkag thiab qhov hluav taws xob ntawm cov pa roj thiab lub thermocouple.Cov thermocouple probes tau insulated nrog cov raj ceramic thiab muab tso rau hauv tib lub sijhawm rau txhua qhov kev sim los tiv thaiv kev sib tsoo.Lub caij no, lub borosilicate iav reactor nrog lub hau peb lub qhov tau siv los ua kom haum rau cov qauv thiab cov trachea.Daim duab schematic ntawm lub microwave reactor tuaj yeem raug xa mus rau hauv Daim Duab Ntxiv 1.
Siv cov roj txiv maj phaub roj ua cov pa roj carbon precursor thiab ferrocene ua cov khoom siv hluav taws xob, cov hlau nplaum nanocarbons tau ua ke.Txog 5% los ntawm qhov hnyav ntawm ferrocene catalyst tau npaj los ntawm slurry catalyst txoj kev.Ferrocene tau tov nrog 20 ml ntawm cov roj txiv maj phaub roj ntawm 60 rpm rau 30 feeb.Tom qab ntawd cov sib tov tau hloov mus rau alumina crucible, thiab 30 cm ntev stainless hlau xaim tau coiled thiab muab tso rau hauv vertically hauv lub crucible.Muab cov alumina crucible tso rau hauv lub khob reactor thiab muab nws ruaj ntseg hauv lub qhov cub microwave nrog lub hau kaw.Nitrogen tau tshuab mus rau hauv lub chamber 5 feeb ua ntej pib cov tshuaj tiv thaiv kom tshem tawm cov huab cua tsis zoo ntawm lub chamber.Lub zog microwave tau nce mus rau 800W vim qhov no yog lub zog microwave siab tshaj plaws uas tuaj yeem tswj tau qhov pib zoo.Yog li ntawd, qhov no yuav ua rau muaj kev tsim cov kev mob zoo rau cov tshuaj tiv thaiv hluavtaws.Nyob rau tib lub sijhawm, qhov no kuj yog siv ntau lub zog hauv watts rau microwave fusion reactions48,49.Qhov sib tov tau muab rhaub rau 10, 15 lossis 20 feeb thaum cov tshuaj tiv thaiv.Tom qab ua tiav cov tshuaj tiv thaiv, lub reactor thiab microwave tau txias txias rau chav sov.Cov khoom kawg hauv alumina crucible yog dub precipitate nrog helical nyob ntawm tej.
Cov hmoov av dub tau sau thiab ntxuav ob peb zaug ua ke nrog ethanol, isopropanol (70%) thiab dej distilled.Tom qab ntxuav thiab ntxuav, cov khoom yog qhuav ib hmos ntawm 80 ° C nyob rau hauv ib tug pa qhov cub kom evaporate pliaj impurities.Tom qab ntawd cov khoom tau muab sau ua tus cwj pwm.Cov qauv sau npe MNC10, MNC15, thiab MNC20 tau siv los ua ke sib nqus nanocarbons rau 10 min, 15 min, thiab 20 min.
Saib MNC morphology nrog lub teb emission scanning electron microscope lossis FESEM (Zeiss Auriga qauv) ntawm 100 txog 150 kX magnification.Nyob rau tib lub sijhawm, cov ntsiab lus tseem ceeb tau txheeb xyuas los ntawm lub zog-dispersive X-ray spectroscopy (EDS).Kev tsom xam EMF tau ua tiav ntawm kev ua haujlwm nrug ntawm 2.8 hli thiab qhov nrawm nrawm ntawm 1 kV.Cov cheeb tsam tshwj xeeb thiab MNC pore qhov tseem ceeb tau ntsuas los ntawm Brunauer-Emmett-Teller (BET) txoj kev, suav nrog cov adsorption-desorption isotherm ntawm N2 ntawm 77 K. Kev tshuaj xyuas tau ua los ntawm cov qauv ntsuas thaj tsam (MICROMERITIC ASAP 2020) .
Lub crystallinity thiab theem ntawm cov hlau nplaum nanocarbons tau txiav txim los ntawm X-ray hmoov diffraction los yog XRD (Burker D8 Advance) ntawm λ = 0.154 nm.Diffractograms tau kaw ntawm 2θ = 5 thiab 85 ° ntawm qhov ntsuas ntawm 2 ° min-1.Tsis tas li ntawd, cov qauv tshuaj ntawm MNCs tau tshawb xyuas siv Fourier transform infrared spectroscopy (FTIR).Kev tsom xam tau ua tiav siv Perkin Elmer FTIR-Spectrum 400 nrog scan nrawm ntawm 4000 txog 400 cm-1.Hauv kev kawm txog cov yam ntxwv ntawm cov hlau nplaum nanocarbons, Raman spectroscopy tau ua los ntawm neodymium-doped laser (532 nm) hauv U-RAMAN spectroscopy nrog lub hom phiaj 100X.
Lub vibrating magnetometer lossis VSM (Lake Shore 7400 series) tau siv los ntsuas qhov sib nqus saturation ntawm hlau oxide hauv MNCs.Ib thaj chaw sib nqus ntawm li 8 kOe tau siv thiab 200 cov ntsiab lus tau txais.
Thaum kawm txog lub peev xwm ntawm MNCs li adsorbents hauv kev sim adsorption, cationic dye methylene xiav (MB) tau siv.MNCs (20 mg) tau ntxiv rau 20 ml ntawm cov tshuaj aqueous ntawm methylene xiav nrog cov txheej txheem ntau ntawm 5-20 mg / L50.Cov pH ntawm cov tshuaj tau teem rau nruab nrab pH ntawm 7 thoob plaws hauv txoj kev tshawb no.Qhov kev daws teeb meem tau sib xyaw ua ke ntawm 150 rpm thiab 303.15 K ntawm lub tshuab nqus dej (Lab Companion: SI-300R).Tom qab ntawd cov MNCs raug cais los ntawm cov hlau nplaum.Siv lub UV-pom spectrophotometer (Varian Cary 50 UV-Vis Spectrophotometer) los soj ntsuam qhov concentration ntawm MB tov ua ntej thiab tom qab kev sim adsorption, thiab xa mus rau methylene xiav qauv nkhaus ntawm qhov siab tshaj plaws wavelength ntawm 664 nm.Qhov kev sim tau rov ua dua peb zaug thiab qhov nruab nrab tus nqi tau muab.Kev tshem tawm ntawm MG los ntawm kev daws tau suav nrog kev sib npaug dav rau tus nqi ntawm MC adsorbed ntawm equilibrium qe thiab qhov feem pua ntawm kev tshem tawm %.
Kev sim ntawm adsorption isotherm kuj tau ua nrog nplawm ntawm ntau qhov ntau (5-20 mg / l) ntawm MG kev daws teeb meem thiab 20 mg ntawm cov adsorbent ntawm qhov kub thiab txias ntawm 293.15 K mg rau tag nrho MNCs.
Hlau thiab hlau nplaum carbon tau raug tshawb fawb ntau dhau ob peb lub xyoo dhau los.Cov khoom siv hlau nplaum uas muaj cov pa roj carbon monoxide no tau ntxim nyiam vim lawv cov khoom siv hluav taws xob zoo heev, ua rau muaj ntau yam kev siv thev naus laus zis, feem ntau hauv cov khoom siv hluav taws xob thiab kev kho dej.Nyob rau hauv txoj kev tshawb no, nanocarbons tau synthesized los ntawm cracking hydrocarbons nyob rau hauv crude xibtes roj siv ib tug microwave tso tawm.Kev sib xyaw ua ke tau ua nyob rau lub sijhawm sib txawv, los ntawm 10 mus rau 20 min, ntawm qhov sib piv ruaj khov (5: 1) ntawm cov khoom siv ua ntej thiab cov khoom siv hluav taws xob, siv cov khoom siv hlau tam sim no (twisted SS) thiab ib nrab inert (tsis xav tau huab cua purged nrog nitrogen ntawm qhov chaw. pib ntawm qhov kev sim).Qhov tshwm sim carbonaceous deposits yog nyob rau hauv daim ntawv ntawm ib tug dub khoom hmoov, raws li qhia nyob rau hauv Ntxiv Fig. 2a.Lub precipitated carbon yields yog kwv yees li 5.57%, 8.21%, thiab 11.67% ntawm synthesis lub sij hawm ntawm 10 feeb, 15 feeb, thiab 20 feeb, feem.Qhov xwm txheej no qhia tias lub sijhawm sib xyaw ua ke ntev ua rau muaj txiaj ntsig ntau dua 51-yields tsawg, feem ntau yuav yog vim lub sijhawm luv luv thiab kev ua haujlwm qis.
Meanwhile, ib zajlus ntawm synthesis kub piv rau lub sij hawm rau cov tau nanocarbons yuav raug xa mus rau hauv Supplementary Figure 2b.Qhov kub siab tshaj plaws tau txais rau MNC10, MNC15 thiab MNC20 yog 190.9 ° C, 434.5 ° C thiab 472 ° C, feem.Rau txhua qhov nkhaus, txoj kab nqes hav tuaj yeem pom, qhia tau tias qhov kub thiab txias nyob rau hauv lub reactor vim lub tshav kub generated thaum lub sij hawm hlau arc.Qhov no tuaj yeem pom ntawm 0–2 min, 0–5 min, thiab 0–8 min rau MNC10, MNC15, thiab MNC20, feem.Tom qab ncav cuag ib qho taw tes, txoj kab nqes txuas ntxiv mus rau qhov kub siab tshaj plaws, thiab txoj kab nqes ua rau nruab nrab.
Field emission scanning electron microscopy (FESEM) tau siv los saib xyuas qhov chaw saum toj kawg nkaus ntawm MNC cov qauv.Raws li qhia hauv daim duab.1, magnetic nanocarbons muaj ib tug me ntsis txawv morphological qauv ntawm lub sij hawm sib txawv ntawm synthesis.Cov duab ntawm FESEM MNC10 hauv daim duab.1a, b qhia tau hais tias qhov tsim ntawm carbon spheres muaj entangled thiab txuas nrog micro- thiab nanospheres vim muaj qhov siab ntom ntom.Nyob rau tib lub sij hawm, lub xub ntiag ntawm van der Waals rog ua rau lub aggregation ntawm carbon spheres52.Qhov nce ntawm lub sij hawm synthesis ua rau qhov me me thiab qhov nce ntawm cov spheres vim muaj kev cuam tshuam ntev dua.Ntawm daim duab.1c qhia tau hais tias MNC15 muaj qhov yuav luag zoo meej kheej kheej.Txawm li cas los xij, cov spheres sib sau ua ke tseem tuaj yeem tsim mesopores, uas tuaj yeem dhau los ua qhov chaw zoo rau methylene xiav adsorption.Ntawm qhov kev nthuav dav siab ntawm 15,000 zaug hauv daim duab 1d ntau carbon spheres tuaj yeem pom agglomerated nrog qhov nruab nrab loj ntawm 20.38 nm.
FESEM dluab ntawm synthesized nanocarbons tom qab 10 min (a, b), 15 min (c, d) thiab 20 min (e–g) ntawm 7000 thiab 15000 zaus magnification.
Ntawm daim duab.1e-g MNC20 piav qhia txog kev loj hlob ntawm pores nrog me me spheres ntawm qhov chaw ntawm cov hlau nplaum sib nqus thiab rov sib sau ua ke ntawm morphology ntawm magnetic activated carbon53.Pores ntawm txawv diameters thiab dav yog random nyob rau saum npoo ntawm hlau nplaum carbon.Yog li, qhov no tuaj yeem piav qhia vim li cas MNC20 tau pom thaj tsam ntau dua thiab qhov pore ntim raws li qhia los ntawm BET tsom xam, raws li ntau qhov pores tsim ntawm nws qhov chaw dua li lwm lub sijhawm hluavtaws.Micrographs coj los ntawm qhov kev nthuav dav siab ntawm 15,000 lub sij hawm pom qhov loj me me thiab cov duab tsis zoo, raws li qhia hauv daim duab 1g.Thaum lub sij hawm loj hlob tau nce mus rau 20 feeb, ntau agglomerated spheres tau tsim.
Interestingly, twisted carbon flakes kuj pom nyob rau hauv tib cheeb tsam.Txoj kab uas hla ntawm spheres txawv ntawm 5.18 mus rau 96.36 nm.Qhov kev tsim no yuav yog vim qhov tshwm sim ntawm qhov sib txawv nucleation, uas yog yooj yim los ntawm qhov kub thiab txias microwaves.Qhov ntsuas qhov loj me ntawm MNCs npaj tau nruab nrab 20.38 nm rau MNC10, 24.80 nm rau MNC15, thiab 31.04 nm rau MNC20.Qhov luaj li cas ntawm spheres yog qhia nyob rau hauv lub supplementary fig.3.
Daim duab ntxiv 4 qhia txog EDS spectra thiab cov ntsiab lus ntawm cov ntsiab lus ntawm MNC10, MNC15, thiab MNC20, raws li.Raws li cov spectra, nws tau sau tseg tias txhua tus nanocarbon muaj qhov sib txawv ntawm C, O, thiab Fe.Qhov no yog vim muaj ntau yam oxidation thiab cracking tshwm sim thaum lub sij hawm ntxiv synthesis.Ib tug loj npaum li cas ntawm C ntseeg tau los ntawm cov pa roj carbon precursor, crude xibtes roj.Lub caij no, qhov feem pua ntawm O yog vim cov txheej txheem oxidation thaum lub sij hawm synthesis.Nyob rau tib lub sijhawm, Fe yog ntaus nqi rau hlau oxide tso rau ntawm nanocarbon nto tom qab ferrocene decomposition.Ntxiv rau, Daim duab 5a-c qhia txog daim ntawv qhia ntawm MNC10, MNC15, thiab MNC20 cov ntsiab lus.Raws li daim ntawv qhia hauv paus, nws tau pom tias Fe tau muab faib zoo tshaj ntawm MNC nto.
Nitrogen adsorption-desorption tsom xam muab cov ntaub ntawv hais txog lub adsorption mechanism thiab cov qauv ntxeem tau ntawm cov khoom.N2 adsorption isotherms thiab graphs ntawm MNC BET nto yog qhia hauv daim duab.2. Raws li cov duab FESEM, tus cwj pwm adsorption yuav tsum muaj kev sib xyaw ua ke ntawm cov qauv microporous thiab mesoporous vim kev sib sau ua ke.Txawm li cas los xij, daim duab hauv daim duab 2 qhia tias cov adsorbent zoo li hom IV isotherm thiab hom H2 hysteresis voj ntawm IUPAC55.Hom isotherm no feem ntau zoo ib yam li cov ntaub ntawv mesoporous.Tus cwj pwm adsorption ntawm mesopores feem ntau yog txiav txim siab los ntawm kev sib cuam tshuam ntawm adsorption-adsorption cov tshuaj tiv thaiv nrog cov molecules ntawm condensed teeb meem.S-shaped los yog S-shaped adsorption isotherms feem ntau yog tshwm sim los ntawm ib txheej txheej-multilayer adsorption ua raws li qhov tshwm sim uas cov roj condenses rau hauv cov kua theem hauv qhov hws ntawm qhov siab hauv qab lub siab saturation ntawm cov kua ntau, hu ua pore condensation 56. Capillary condensation nyob rau hauv pores tshwm sim ntawm tus txheeb ze pressures (p / po) saum toj no 0.50.Meanwhile, lub complex pore qauv nthuav tawm H2-hom hysteresis, uas yog vim lub pore plugging los yog to nyob rau hauv ib tug nqaim ntau ntawm pores.
Lub cev tsis sib xws ntawm qhov chaw tau txais los ntawm BET cov kev xeem tau pom nyob rau hauv Table 1. Qhov chaw BET nto thiab tag nrho cov pore ntim tau nce ntxiv nrog rau lub sijhawm sib xyaw ua ke.Qhov nruab nrab pore qhov loj me ntawm MNC10, MNC15, thiab MNC20 yog 7.2779 nm, 7.6275 nm, thiab 7.8223 nm, feem.Raws li IUPAC cov lus pom zoo, cov pores nruab nrab no tuaj yeem faib ua cov khoom mesoporous.Cov qauv mesoporous tuaj yeem ua rau methylene xiav yooj yim dua permeable thiab adsorbable los ntawm MNC57.Lub Sijhawm Synthesis Maximum (MNC20) pom qhov chaw siab tshaj plaws, ua raws li MNC15 thiab MNC10.BET qhov chaw siab dua tuaj yeem txhim kho kev ua haujlwm adsorption vim tias muaj ntau qhov chaw surfactant.
X-ray diffraction qauv ntawm cov synthesized MNCs muaj nyob rau hauv daim duab 3. Thaum kub kub, ferrocene kuj tawg thiab cov hlau oxide.Ntawm daim duab.3a qhia XRD qauv ntawm MNC10.Nws qhia tau hais tias ob lub ncov ntawm 2θ, 43.0° thiab 62.32°, uas tau muab rau ɣ-Fe2O3 (JCPDS #39–1346).Nyob rau tib lub sijhawm, Fe3O4 muaj strained ncov ntawm 2θ: 35.27 °.Ntawm qhov tod tes, nyob rau hauv MHC15 diffraction qauv hauv daim duab 3b qhia cov ncov tshiab, uas feem ntau yuav cuam tshuam nrog qhov nce ntawm qhov kub thiab txias thiab lub sijhawm sib xyaw.Txawm hais tias 2θ: 26.202 ° ncov tsis tshua muaj siab, cov qauv diffraction yog raws li graphite JCPDS cov ntaub ntawv (JCPDS #75-1621), qhia tias muaj cov graphite muaju nyob rau hauv nanocarbon.Lub ncov no tsis tuaj hauv MNC10, tejzaum nws yog vim qhov kub arc qis thaum lub sijhawm sib txuas.Ntawm 2θ muaj peb lub sijhawm peaks: 30.082°, 35.502°, 57.422° ntaus nqi rau Fe3O4.Nws kuj qhia tau hais tias ob lub ncov qhia tias muaj ɣ-Fe2O3 ntawm 2θ: 43.102° thiab 62.632°.Rau MNC synthesized rau 20 min (MNC20), raws li qhia nyob rau hauv daim duab 3c, ib tug zoo sib xws diffraction qauv yuav pom nyob rau hauv MNK15.Lub nraaj ncov ntawm 26.382 ° tuaj yeem pom hauv MNC20.Peb lub ncov ntse pom ntawm 2θ: 30.102 °, 35.612 °, 57.402 ° yog rau Fe3O4.Tsis tas li ntawd, lub xub ntiag ntawm ε-Fe2O3 yog qhia ntawm 2θ: 42.972 ° thiab 62.61.Lub xub ntiag ntawm cov hlau oxide sib txuas hauv MNCs tuaj yeem muaj txiaj ntsig zoo rau lub peev xwm adsorb methylene xiav yav tom ntej.
Cov yam ntxwv ntawm daim ntawv cog lus hauv MNC thiab CPO cov qauv raug txiav txim siab los ntawm FTIR reflectance spectra nyob rau hauv Ntxiv daim duab 6. Thaum pib, rau lub ncov tseem ceeb ntawm cov txiv maj phaub roj sawv cev plaub yam tshuaj sib txawv raws li tau piav qhia hauv Cov Lus Ntxiv 1. Cov peaks tseem ceeb tau txheeb xyuas hauv CPO yog 2913.81 cm-1, 2840 cm-1 thiab 1463.34 cm-1, uas xa mus rau CH stretching vibrations ntawm alkanes thiab lwm aliphatic CH2 los yog CH3 pawg.Lub ncov roob hav zoov yog 1740.85 cm-1 thiab 1160.83 cm-1.Lub ncov ntawm 1740.85 cm-1 yog C = O daim ntawv cog lus txuas ntxiv los ntawm ester carbonyl ntawm triglyceride ua haujlwm pab pawg.Lub caij no, lub ncov ntawm 1160.83 cm-1 yog qhov imprint ntawm txuas ntxiv CO58.59 ester pawg.Lub caij no, lub ncov ntawm 813.54 cm-1 yog lub cim ntawm pawg alkane.
Yog li ntawd, qee qhov kev nqus tau nce siab hauv cov roj txiv maj phaub roj ploj lawm thaum lub sijhawm sib xyaw ua ke tau nce.Peaks ntawm 2913.81 cm-1 thiab 2840 cm-1 tseem tuaj yeem pom hauv MNC10, tab sis nws yog qhov nthuav tias hauv MNC15 thiab MNC20 lub ncov zoo li ploj vim oxidation.Lub caij no, FTIR kev tshuaj xyuas ntawm cov hlau nplaum nanocarbons tau nthuav tawm tshiab tsim lub siab nqus nqus sawv cev rau tsib pawg ua haujlwm sib txawv ntawm MNC10-20.Cov ncov no kuj tau teev tseg hauv Cov Lus Ntxiv 1. Lub ncov ntawm 2325.91 cm-1 yog asymmetric CH stretch ntawm CH360 aliphatic pawg.Lub ncov ntawm 1463.34-1443.47 cm-1 qhia CH2 thiab CH dabtsi yog khoov ntawm aliphatic pawg xws li xibtes roj, tab sis lub ncov pib nrog lub sij hawm.Lub ncov ntawm 813.54–875.35 cm–1 yog ib qho imprint ntawm pawg CH-alkane aromatic.
Lub caij no, lub ncov ntawm 2101.74 cm-1 thiab 1589.18 cm-1 sawv cev rau CC 61 daim ntawv cog lus ua C = C alkyne thiab aromatic rings, feem.Lub ncov me me ntawm 1695.15 cm-1 qhia tau hais tias C = O daim ntawv cog lus ntawm cov dawb fatty acid los ntawm pawg carbonyl.Nws yog tau los ntawm CPO carbonyl thiab ferrocene thaum lub sij hawm synthesis.Lub ncov tsim tshiab nyob rau hauv thaj tsam ntawm 539.04 txog 588.48 cm-1 yog rau Fe-O vibrational bond ntawm ferrocene.Raws li cov peaks qhia nyob rau hauv Ntxiv Daim duab 4, nws tuaj yeem pom tias lub sijhawm sib xyaw ua ke tuaj yeem txo ob peb lub ncov thiab rov sib txuas hauv cov hlau nplaum nanocarbons.
Spectroscopic tsom xam ntawm Raman tawg ntawm cov hlau nplaum nanocarbons tau nyob rau hauv sib txawv lub sij hawm ntawm synthesis siv ib tug teeb meem laser nrog ib tug wavelength ntawm 514 nm yog qhia nyob rau hauv daim duab 4. Tag nrho cov spectra ntawm MNC10, MNC15 thiab MNC20 muaj ob khaus bands txuam nrog tsawg sp3 carbon, feem ntau pom nyob rau hauv nanographite crystallites nrog qhov tsis xws luag hauv vibrational hom ntawm carbon hom sp262.Thawj lub ncov, nyob rau hauv thaj tsam ntawm 1333–1354 cm–1, sawv cev rau D band, uas yog qhov tsis zoo rau cov graphite zoo tagnrho thiab sib raug rau cov qauv kev tsis sib haum xeeb thiab lwm yam impurities63,64.Qhov thib ob tseem ceeb tshaj plaws ncov nyob ib ncig ntawm 1537-1595 cm-1 tshwm sim los ntawm hauv-dav hlau daim ntawv cog lus stretching los yog crystalline thiab txiav txim graphite cov ntaub ntawv.Txawm li cas los xij, lub ncov hloov ntawm li 10 cm-1 piv rau graphite G band, qhia tias MNCs muaj cov ntawv qis qis thiab cov qauv tsis zoo.Cov txheeb ze siv zog ntawm D thiab G bands (ID / IG) yog siv los ntsuas qhov purity ntawm crystallites thiab graphite qauv.Raws li Raman spectroscopic tsom xam, tag nrho cov MNCs muaj ID / IG qhov tseem ceeb nyob rau hauv thaj tsam ntawm 0.98–0.99, qhia txog cov yam ntxwv tsis xws luag vim Sp3 hybridization.Qhov xwm txheej no tuaj yeem piav qhia txog qhov muaj qhov tsis tshua muaj siab 2θ peaks hauv XPA spectra: 26.20 ° rau MNK15 thiab 26.28 ° rau MNK20, raws li qhia hauv daim duab 4, uas tau muab rau cov graphite ncov hauv JCPDS cov ntaub ntawv.Tus ID / IG MNC qhov sib piv tau txais hauv txoj haujlwm no yog nyob rau hauv ntau ntawm lwm cov hlau nplaum nanocarbons, piv txwv li, 0.85–1.03 rau txoj kev hydrothermal thiab 0.78–0.9665.66 rau txoj kev pyrolytic.Yog li, qhov piv txwv no qhia tau hais tias tam sim no cov txheej txheem hluavtaws tuaj yeem siv dav.
Cov yam ntxwv sib nqus ntawm MNCs tau txheeb xyuas siv lub vibrating magnetometer.Qhov tshwm sim hysteresis yog qhia hauv Fig.5.Raws li txoj cai, MNCs tau txais lawv cov hlau nplaum los ntawm ferrocene thaum sib txuas.Cov khoom sib nqus ntxiv no tuaj yeem ua rau muaj peev xwm adsorption ntawm nanocarbons yav tom ntej.Raws li pom hauv daim duab 5, cov qauv tuaj yeem txheeb xyuas tau tias yog cov khoom siv superparamagnetic.Raws li Wahajuddin & Arora67, lub xeev superparamagnetic yog tias cov qauv yog magnetized rau saturation magnetization (MS) thaum siv sab nraud magnetic teb.Tom qab ntawd, qhov seem sib nqus sib nqus tsis tshwm sim hauv cov qauv 67.Nws yog noteworthy tias saturation magnetization nce nrog lub sij hawm synthesis.Interestingly, MNC15 muaj qhov siab tshaj plaws sib nqus saturation vim muaj zog sib nqus tsim (magneticization) tuaj yeem tshwm sim los ntawm kev pom lub sijhawm sib nqus nyob rau hauv lub xub ntiag ntawm cov hlau nplaum sab nraud.Qhov no yuav yog vim muaj Fe3O4, uas muaj cov khoom sib nqus zoo dua piv rau lwm cov hlau oxides xws li ɣ-Fe2O.Qhov kev txiav txim ntawm lub sijhawm adsorption ntawm saturation ib chav tsev loj ntawm MNCs yog MNC15> MNC10> MNC20.Cov taumagnetic tsis tau muab rau hauv lub rooj.2.
Qhov tsawg kawg nkaus tus nqi ntawm cov hlau nplaum saturation thaum siv cov hlau nplaum sib nqus sib nqus yog li 16.3 emu g-1.Lub peev xwm ntawm MNCs tshem tawm cov kab mob xws li dyes nyob rau hauv ib puag ncig dej thiab qhov yooj yim ntawm kev tshem tawm ntawm MNCs tau dhau los ua lwm yam ntxiv rau cov nanocarbons tau txais.Cov kev tshawb fawb tau pom tias qhov sib nqus saturation ntawm LSM yog suav tias yog siab.Yog li, tag nrho cov qauv mus txog qhov sib nqus saturation qhov tseem ceeb tshaj qhov txaus rau cov txheej txheem sib nqus sib nqus.
Tsis ntev los no, hlau strips lossis xov hlau tau nyiam cov catalysts lossis dielectrics hauv microwave fusion txheej txheem.Microwave cov tshuaj tiv thaiv ntawm cov hlau ua rau kub siab lossis cov tshuaj tiv thaiv hauv lub reactor.Txoj kev tshawb no tau lees tias qhov ntxeev thiab txias (coiled) stainless hlau xaim ua kom yooj yim rau microwave tawm thiab cua sov hlau.Stainless hlau tau tshaj tawm roughness ntawm lub taub, uas ua rau muaj txiaj ntsig zoo ntawm cov nqi hluav taws xob sab nraud thiab sab nraud hluav taws xob.Thaum tus nqi tau txais lub zog kinetic txaus, cov khoom them nqi yuav dhia tawm ntawm cov hlau tsis muaj steel, ua rau ib puag ncig ionize, tsim tawm los yog lub txim 68.Hlau tso tawm ua rau muaj txiaj ntsig zoo rau kev daws cov tshuaj tiv thaiv tawg nrog rau qhov kub thiab txias kub.Raws li daim ntawv qhia qhov kub thiab txias hauv Supplementary Fig. 2b, qhov kub thiab txias tau nce sai, qhia tias muaj qhov kub thiab txias ntawm qhov kub thiab txias ntxiv rau qhov tshwm sim muaj zog tawm.
Nyob rau hauv cov ntaub ntawv no, ib tug thermal nyhuv yog pom, vim tsis muaj zog bound electrons tuaj yeem txav thiab mloog zoo rau ntawm qhov chaw thiab ntawm lub tip69.Thaum cov hlau tsis muaj qhov txhab, qhov loj ntawm qhov chaw ntawm cov hlau hauv kev daws teeb meem pab cuam tshuam cov eddy tam sim no ntawm cov khoom siv thiab tswj cov cua sov.Qhov xwm txheej no zoo pab txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txuas cov roj carbon ntev ntawm CPO thiab ferrocene thiab ferrocene.Raws li pom nyob rau hauv Ntxiv Fig. 2b, qhov ntsuas kub tsis tu ncua qhia tau hais tias qhov ntsuas kub tsis sib xws tau pom hauv cov tshuaj.
Lub tswv yim txheej txheem rau kev tsim MNCs yog qhia nyob rau hauv Ntxiv daim duab 7. Cov roj carbon ntev ntawm CPO thiab ferrocene pib tawg ntawm qhov kub thiab txias.Cov roj tawg los ua cov hydrocarbons sib cais uas ua cov pa roj carbon precursors hu ua globules hauv FESEM MNC1070 duab.Vim lub zog ntawm ib puag ncig thiab siab 71 nyob rau hauv atmospheric tej yam kev mob.Nyob rau tib lub sijhawm, ferrocene kuj tawg, tsim cov catalyst los ntawm carbon atoms tso rau Fe.Cov nucleation sai sai tshwm sim thiab cov tub ntxhais carbon oxidizes los ua ib qho amorphous thiab graphitic carbon txheej rau saum cov tub ntxhais.Raws li lub sij hawm nce, qhov luaj li cas ntawm tus kheej ua ntau meej thiab zoo ib yam.Nyob rau tib lub sijhawm, cov tub rog van der Waals uas twb muaj lawm kuj ua rau lub agglomeration ntawm spheres52.Thaum lub sij hawm txo Fe ions rau Fe3O4 thiab ɣ-Fe2O3 (raws li kev tsom xam X-ray theem), ntau hom hlau oxides yog tsim nyob rau saum npoo ntawm nanocarbons, uas ua rau tsim cov hlau nplaum nanocarbons.EDS daim ntawv qhia tau pom tias Fe atoms tau muab faib rau saum npoo ntawm MNC, raws li qhia hauv Cov Duab Ntxiv 5a-c.
Qhov txawv yog hais tias thaum lub sij hawm synthesis ntawm 20 feeb, carbon aggregation tshwm sim.Nws tsim cov pores loj dua rau saum npoo ntawm MNCs, qhia tias MNCs tuaj yeem suav tias yog cov pa roj carbon activated, raws li qhia hauv FESEM cov duab hauv daim duab 1e–g.Qhov sib txawv ntawm qhov pore qhov ntau thiab tsawg yuav cuam tshuam nrog kev koom tes ntawm hlau oxide los ntawm ferrocene.Nyob rau tib lub sijhawm, vim qhov kub siab mus txog, muaj cov nplai deformed.Sib nqus nanocarbons nthuav tawm cov morphologies sib txawv ntawm lub sijhawm sib txawv.Nanocarbons feem ntau yuav tsim cov duab kheej kheej nrog lub sijhawm luv luv.Nyob rau tib lub sijhawm, qhov pores thiab nplai tuaj yeem ua tiav, txawm hais tias qhov sib txawv ntawm lub sijhawm sib xyaw tsuas yog nyob rau hauv 5 feeb.
Sib nqus nanocarbons tuaj yeem tshem tawm cov pa phem los ntawm cov dej hauv dej.Lawv lub peev xwm kom tau yooj yim tshem tawm tom qab siv yog ib qho tseem ceeb ntxiv rau kev siv cov nanocarbons tau txais hauv txoj haujlwm no ua cov adsorbents.Hauv kev kawm txog cov khoom adsorption ntawm cov hlau nplaum nanocarbons, peb tau tshawb xyuas lub peev xwm ntawm MNCs los decolorize methylene xiav (MB) kev daws teeb meem ntawm 30 ° C yam tsis muaj pH hloov.Ntau qhov kev tshawb fawb tau xaus lus tias kev ua haujlwm ntawm cov pa roj carbon monoxide nyob rau hauv qhov kub ntawm 25-40 ° C tsis ua lub luag haujlwm tseem ceeb hauv kev txiav txim siab MC tshem tawm.Txawm hais tias huab pH qhov tseem ceeb ua lub luag haujlwm tseem ceeb, cov nqi them tuaj yeem tsim rau ntawm pawg ua haujlwm saum npoo av, uas ua rau muaj kev cuam tshuam ntawm adsorbate-adsorbent kev sib cuam tshuam thiab cuam tshuam rau adsorption.Yog li ntawd, cov xwm txheej saum toj no tau raug xaiv hauv txoj kev tshawb fawb no los txiav txim siab txog cov xwm txheej no thiab xav tau kev kho dej khib nyiab.
Hauv kev ua haujlwm no, kev sim batch adsorption tau ua los ntawm kev ntxiv 20 mg ntawm MNCs rau 20 ml ntawm cov tshuaj aqueous ntawm methylene xiav nrog ntau yam qauv thawj zaug (5-20 ppm) ntawm lub sijhawm tiv tauj 60.Ntxiv daim duab 8 qhia txog cov xwm txheej ntawm ntau qhov ntau (5-20 ppm) ntawm cov tshuaj methylene xiav ua ntej thiab tom qab kho nrog MNC10, MNC15, thiab MNC20.Thaum siv ntau yam MNCs, cov xim ntawm MB cov kev daws teeb meem poob.Interestingly, nws tau pom tias MNC20 yooj yim discolored MB daws ntawm ib tug concentration ntawm 5 ppm.Lub caij no, MNC20 kuj txo cov xim ntawm cov tshuaj MB piv rau lwm cov MNCs.UV pom spectrum ntawm MNC10-20 yog qhia nyob rau hauv Ntxiv daim duab 9. Meanwhile, tus nqi tshem tawm thiab adsorption cov ntaub ntawv qhia nyob rau hauv daim duab 9. 6 thiab nyob rau hauv lub rooj 3, raws li.
Muaj zog methylene xiav peaks tuaj yeem pom ntawm 664 nm thiab 600 nm.Raws li txoj cai, qhov kev siv ntawm lub ncov maj mam txo qis nrog kev txo qis thawj zaug ntawm cov tshuaj MG.Nyob rau hauv qhov ntxiv Fig. 9a qhia txog UV-pom pom spectra ntawm MB kev daws teeb meem ntawm ntau yam concentrations tom qab kev kho mob nrog MNC10, uas tsuas yog me ntsis hloov qhov kev siv ntawm cov peaks.Ntawm qhov tod tes, qhov nqus siab tshaj plaws ntawm MB cov kev daws teeb meem tau txo qis tom qab kev kho mob nrog MNC15 thiab MNC20, raws li qhia hauv Cov Duab Ntxiv 9b thiab c, raws li.Cov kev hloov no tau pom meej meej vim tias qhov concentration ntawm cov tshuaj MG txo qis.Txawm li cas los xij, qhov kev hloov pauv spectral ua tiav los ntawm tag nrho peb cov hlau nplaum sib nqus tau txaus los tshem tawm cov xim xiav methylene.
Raws li cov lus 3, cov txiaj ntsig ntawm MC adsorbed thiab qhov feem pua ntawm MC adsorbed yog qhia hauv daim duab 3. 6. Cov adsorption ntawm MG tau nce nrog kev siv ntau dua thawj zaug rau tag nrho MNCs.Lub caij no, qhov feem pua adsorption lossis MB tshem tawm tus nqi (MBR) pom qhov txawv txav thaum thawj qhov concentration nce.Nyob rau hauv qis dua thawj zaug MC concentrations, unoccupied active chaw tseem nyob rau ntawm adsorbent nto.Raws li qhov dye concentration nce, tus naj npawb ntawm cov chaw uas tsis muaj nyob hauv cov chaw muaj rau adsorption ntawm dye molecules yuav txo qis.Lwm tus tau xaus lus tias nyob rau hauv cov xwm txheej no saturation ntawm cov chaw nquag ntawm biosorption yuav ua tiav 72.
Hmoov tsis zoo rau MNC10, MBR nce thiab txo qis tom qab 10 ppm ntawm MB daws.Nyob rau tib lub sijhawm, tsuas yog ib feem me me ntawm MG yog adsorbed.Qhov no qhia tau hais tias 10 ppm yog qhov zoo tshaj plaws concentration rau MNC10 adsorption.Rau tag nrho cov MNCs kawm nyob rau hauv txoj hauj lwm no, qhov kev txiav txim ntawm adsorption capacities yog raws li nram no: MNC20 > MNC15 > MNC10, qhov nruab nrab qhov tseem ceeb yog 10.36 mg / g, 6.85 mg / g thiab 0.71 mg / g, qhov nruab nrab tshem tawm ntawm MG tus nqi. yog 87,79%, 62.26% thiab 5.75%.Yog li, MNC20 tau pom qhov zoo tshaj plaws adsorption yam ntxwv ntawm cov khoom sib nqus nanocarbons, suav nrog cov peev txheej adsorption thiab UV-pom pom spectrum.Txawm hais tias lub peev xwm adsorption qis dua piv rau lwm cov hlau nplaum nanocarbons xws li MWCNT magnetic composite (11.86 mg / g) thiab halloysite nanotube-magnetic Fe3O4 nanoparticles (18.44 mg / g), txoj kev tshawb no tsis tas yuav tsum tau siv cov tshuaj stimulant ntxiv.Cov tshuaj ua haujlwm ua catalysts.muab cov txheej txheem huv thiab ua tau zoo73,74.
Raws li tau pom los ntawm SBET qhov tseem ceeb ntawm MNCs, qhov chaw tshwj xeeb tshwj xeeb muab cov chaw ua haujlwm ntau dua rau cov adsorption ntawm MB daws.Qhov no tau dhau los ua ib qho tseem ceeb ntawm cov khoom siv hluavtaws nanocarbons.Nyob rau tib lub sijhawm, vim qhov me me ntawm MNCs, lub sijhawm sib xyaw ua ke yog luv thiab siv tau, uas sib haum rau cov txiaj ntsig tseem ceeb ntawm kev cog lus adsorbents75.Piv nrog rau cov pa adsorbents, cov synthesized MNCs yog magnetically saturated thiab tuaj yeem tshem tau yooj yim ntawm kev daws raws li qhov kev txiav txim ntawm sab nraud magnetic teb76.Yog li, lub sij hawm yuav tsum tau rau tag nrho cov txheej txheem kho yog txo.
Adsorption isotherms yog qhov tseem ceeb kom nkag siab txog cov txheej txheem adsorption thiab tom qab ntawd los ua kom pom tias cov adsorbate partitions ntawm cov kua thiab cov theem khoom sib npaug thaum ncav cuag.Qhov sib npaug ntawm Langmuir thiab Freundlich yog siv raws li tus qauv isotherm equations, uas piav qhia txog cov txheej txheem ntawm adsorption, raws li qhia hauv daim duab 7. Cov qauv Langmuir zoo qhia txog kev tsim ntawm ib txheej adsorbate rau sab nrauv ntawm cov adsorbent.Isotherms yog qhov zoo tshaj plaws piav raws li homogeneous adsorption nto.Nyob rau tib lub sijhawm, Freundlich isotherm zoo tshaj plaws hais txog kev koom tes ntawm ntau thaj tsam adsorbent thiab lub zog adsorption hauv kev nias lub adsorbate mus rau qhov chaw tsis sib xws.
Qauv isotherm rau Langmuir isotherm (a–c) thiab Freundlich isotherm (d–f) rau MNC10, MNC15 thiab MNC20.
Adsorption isotherms ntawm cov kua qaub qis feem ntau yog linear77.Cov kab sawv cev ntawm tus qauv Langmuir isotherm tuaj yeem qhia hauv qhov sib npaug.1 Txheeb xyuas cov adsorption parameter.
KL (l / mg) yog Langmuir tas li sawv cev rau kev sib txuas ntawm MB rau MNC.Lub caij no, qmax yog qhov siab tshaj plaws adsorption muaj peev xwm (mg / g), qe yog qhov adsorbed concentration ntawm MC (mg / g), thiab Ce yog qhov sib npaug ntawm cov tshuaj MC.Qhov kev qhia tawm ntawm Freundlich isotherm qauv tuaj yeem piav qhia raws li hauv qab no:
Post lub sij hawm: Feb-16-2023