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Ukuba khona kwezinsimbi ezikhishwa imisebe ye-microwave kuyimpikiswano ngoba izinsimbi zivutha kalula.Kodwa okuthakazelisayo ukuthi abacwaningi bathola ukuthi i-arc discharge phenomenon inikeza umzila othembisayo wokuhlanganiswa kwama-nanomaterials ngokuhlukanisa ama-molecule.Lolu cwaningo luthuthukisa indlela yokwenziwa enesinyathelo esisodwa kodwa ethengekayo ehlanganisa ukushisisa i-microwave kanye ne-arc kagesi ukuguqula uwoyela wesundu ongahluziwe ube yi-nanocarbon kazibuthe (MNC), engathathwa njengenye indlela entsha yokukhiqiza uwoyela wesundu.Kubandakanya ukuhlanganiswa kwesikhulumi esinezintambo zensimbi engenasici (i-dielectric medium) ne-ferrocene (catalyst) ngaphansi kwezimo ezingasebenzi kancane.Le ndlela iboniswe ngempumelelo ekushiseni ebangeni lokushisa kusuka ku-190.9 kuya ku-472.0 ° C ngezikhathi ezihlukahlukene zokuhlanganisa (10-20 min).Ama-MNC asanda kulungiswa abonise ama-sphere anosayizi ojwayelekile ongu-20.38–31.04 nm, isakhiwo se-mesoporous (SBET: 14.83–151.95 m2/g) kanye nokuqukethwe okuphezulu kwekhabhoni engaguquki (52.79–71.24 wt.%), kanye no-D no-G amabhendi (ID/g) 0.98–0.99.Ukwakhiwa kweziqongo ezintsha ku-spectrum ye-FTIR (522.29–588.48 cm–1) kufakazela ubukhona bezinhlanganisela ze-FeO ku-ferrocene.Ama-Magnetometer abonisa ukugcwaliswa kwezibuthe okuphezulu (22.32–26.84 emu/g) ezintweni ze-ferromagnetic.Ukusetshenziswa kwama-MNC ekuhlanzeni amanzi angcolile kuboniswe ngokuhlola umthamo wawo we-adsorption kusetshenziswa ukuhlolwa kwe-methylene blue (MB) adsorption ezindaweni ezihlukahlukene kusukela ku-5 kuya ku-20 ppm.Ama-MNC atholwe ngesikhathi sokuhlanganiswa (amaminithi angu-20) abonise ukusebenza kahle okuphezulu kakhulu kwe-adsorption (10.36 mg/g) uma kuqhathaniswa namanye, futhi izinga lokususa udayi we-MB lalingu-87.79%.Ngakho-ke, amanani e-Langmuir awanalo ithemba uma kuqhathaniswa namanani e-Freundlich, kanti u-R2 cishe u-0.80, 0.98 kanye no-0.99 wama-MNCs ahlanganiswe ku-10 min (MNC10), 15 min (MNC15) kanye ne-20 min (MNC20) ngokulandelanayo.Ngenxa yalokho, isistimu ye-adsorption isesimweni esihlukile.Ngakho-ke, i-microwave arcing inikeza indlela ethembisayo yokuguqula i-CPO ibe yi-MNC, engasusa odayi abayingozi.
Imisebe ye-Microwave ingashisisa izingxenye zangaphakathi zezinto zokwakha ngokusebenzisana kwamangqamuzana ezinkambu ze-electromagnetic.Le mpendulo ye-microwave ihlukile ngoba ikhuthaza ukusabela okushisayo okusheshayo nokufana okufanayo.Ngakho-ke, kungenzeka ukusheshisa inqubo yokushisa nokuthuthukisa ukusabela kwamakhemikhali2.Ngesikhathi esifanayo, ngenxa yesikhathi esifushane sokusabela, ukusabela kwe-microwave ekugcineni kungakhiqiza imikhiqizo yokuhlanzeka okuphezulu kanye nesivuno esiphezulu3,4.Ngenxa yezakhiwo zayo ezimangalisayo, imisebe ye-microwave isiza ama-microwave syntheses athakazelisayo asetshenziswa ezifundweni eziningi, okuhlanganisa ukusabela kwamakhemikhali kanye nokuhlanganiswa kwama-nanomaterials5,6.Ngesikhathi sokushisa, izakhiwo ze-dielectric zomamukeli ngaphakathi okuphakathi zidlala indima ebalulekile, ngoba idala indawo eshisayo phakathi, okuholela ekwakhekeni kwama-nanocarbons ane-morphologies ehlukene kanye nezakhiwo.Ucwaningo luka-Omoriyekomwan et al.Ukukhiqizwa kwe-carbon nanofibers engenalutho kusuka ezinkomeni zesundu kusetshenziswa i-activated carbon ne-nitrogen8.Ngaphezu kwalokho, u-Fu no-Hamid banqume ukusetshenziswa kwe-catalyst yokukhiqizwa kwe-oil palm fiber activated carbon kuhhavini ye-microwave engu-350 W9.Ngakho-ke, indlela efanayo ingasetshenziswa ukuguqula uwoyela wesundu ongahluziwe ube yi-MNCs ngokwethula ama-scavenger afanelekile.
Kubonwe into ethokozisayo phakathi kwemisebe ye-microwave nezinsimbi ezinemiphetho ecijile, amachashazi noma ukungalungi kwe-microscopic10.Ukuba khona kwalezi zinto ezimbili kuzothinteka i-arc kagesi noma inhlansi (evame ukubizwa ngokuthi i-arc discharge)11,12.I-arc izothuthukisa ukwakheka kwezindawo ezishisayo ezisendaweni futhi ibe nomthelela ekuphenduleni, ngaleyo ndlela ithuthukise ukwakheka kwamakhemikhali emvelo13.Lesi senzakalo esikhethekile nesithakazelisayo sihehe izifundo ezihlukahlukene ezifana nokususwa kokungcola14,15, i-biomass tar cracking16, i-microwave assisted pyrolysis17,18 kanye ne-material synthesis19,20,21.
Muva nje, ama-nanocarbons afana ne-carbon nanotubes, carbon nanospheres, kanye ne-graphene oxide eshintshiwe eshintshiwe adonse ukunaka ngenxa yezakhiwo zawo.Lawa ma-nanocarbon anamandla amakhulu okusetshenziswa kusukela ekuphehleni ugesi kuya ekuhlanzweni kwamanzi noma ukuqeda ukungcola23.Ngaphezu kwalokho, izakhiwo ezinhle kakhulu ze-carbon ziyadingeka, kodwa ngesikhathi esifanayo, izakhiwo ezinhle zamagnetic ziyadingeka.Lokhu kuwusizo kakhulu ekusetshenzisweni okunemisebenzi eminingi okuhlanganisa ukukhangiswa okuphezulu kwama-ion ensimbi nodayi ekuhlanzeni amanzi angcolile, iziguquli kazibuthe kuma-biofuels kanye nezimunyisi ezisebenza kahle kakhulu ze-microwave24,25,26,27,28.Ngasikhathi sinye, lawa makhabhoni anenye inzuzo, okubandakanya ukwanda kwendawo engaphezulu yesayithi elisebenzayo lesampula.
Eminyakeni yamuva nje, ucwaningo lwezinto ezibonakalayo ze-nanocarbon kazibuthe belulokhu lukhula.Ngokujwayelekile, lawa ma-nanocarbons kazibuthe ayizinto ezisebenzayo eziningi eziqukethe izinto zikazibuthe ezinama-nanosized ezingabangela ama-catalyst angaphandle ukuthi asabele, njengezizinda zangaphandle zikagesi noma ezishintshanayo29.Ngenxa yezakhiwo zawo kazibuthe, ama-nanocarbons azibuthe angahlanganiswa nohlu olubanzi lwezithako ezisebenzayo kanye nezakhiwo eziyinkimbinkimbi ze-immobilization30.Ngaleso sikhathi, ama-nanocarbon kazibuthe (MNCs) abonisa ukusebenza kahle okuhle kakhulu ekukhangiseni ukungcola okuvela ezixazululweni ezinamanzi.Ukwengeza, indawo ephezulu ethize ephezulu kanye nezimbotshana ezakhiwe kuma-MNCs zingakhuphula umthamo we-adsorption31.Izihlukanisi kazibuthe zingahlukanisa ama-MNC ezixazululweni ezisebenza kakhulu, ziwaguqule abe i-sorbent esebenzayo nelawulekayo32.
Abacwaningi abaningana babonise ukuthi izinga eliphezulu le-nanocarbons lingakhiqizwa kusetshenziswa amafutha esundu aluhlaza33,34.Amafutha esundu, aziwa ngokwesayensi ngokuthi i-Elais Guneensis, athathwa njengomunye wamafutha abalulekile adliwayo akhiqizwa cishe amathani ayizigidi ezingama-76.55 ngo-202135. (Isiphathimandla semali saseSingapore).Iningi lama-hydrocarbon ku-CPO yi-triglycerides, i-glyceride eyakhiwe izingxenye ezintathu ze-acetate ye-triglyceride kanye nengxenye eyodwa ye-glycerol36.Lawa ma-hydrocarbon angenziwa jikelele ngenxa yokuqukethwe kwawo okukhulu kwekhabhoni, okuwenza abe izandulela eziluhlaza zokukhiqiza i-nanocarbon37.Ngokusho kwezincwadi, i-CNT37,38,39,40, carbon nanospheres33,41 kanye negraphene34,42,43 zivame ukuhlanganiswa kusetshenziswa uwoyela wesundu ongahluziwe noma uwoyela odliwayo.Lawa ma-nanocarbons anamandla amakhulu ekusetshenzisweni kusukela ekuphehleni amandla ukuya ekuhlanzweni kwamanzi noma ekuqedeni ukungcola.
Ukwenziwa kwe-thermal okufana ne-CVD38 noma i-pyrolysis33 sekuyindlela evumayo yokubola kwamafutha esundu.Ngeshwa, amazinga okushisa aphezulu kule nqubo andisa izindleko zokukhiqiza.Ukukhiqiza impahla ekhethwayo 44 kudinga izinqubo ezinde, eziyisicefe nezindlela zokuhlanza.Kodwa-ke, isidingo sokuhlukaniswa ngokomzimba nokuqhekeka asinakuphikwa ngenxa yokuzinza okuhle kwamafutha esundu aluhlaza emazingeni okushisa aphezulu45.Ngakho-ke, amazinga okushisa aphakeme asadingeka ukuze kuguqulwe uwoyela wesundu ongahluziwe ube yizinto ze-carbonaceous.I-arc ye-liquid ingabhekwa njengendlela engcono kakhulu kanye nendlela entsha yokuhlanganiswa kwe-nanocarbon magnetic 46.Le ndlela inikeza amandla aqondile kuma-precursors kanye nezixazululo ezifundazweni ezijabule kakhulu.Ukukhishwa kwe-arc kungabangela amabhondi ekhabhoni kuwoyela wesundu ongahluziwe ukuthi aphule.Kodwa-ke, isikhala se-electrode esisetshenzisiwe singase sidinge ukuhlangabezana nezidingo eziqinile, ezizokhawulela isikali sezimboni, ngakho-ke indlela ephumelelayo isadinga ukuthuthukiswa.
Ngokwazi kwethu konke, ucwaningo ngokukhishwa kwe-arc kusetshenziswa ama-microwave njengendlela yokuhlanganisa ama-nanocarbons lunqunyelwe.Ngesikhathi esifanayo, ukusetshenziswa kwamafutha esundu angahluziwe njengesandulela akukahlolisiswa ngokugcwele.Ngakho-ke, lolu cwaningo luhlose ukuhlola ukuthi kungenzeka yini ukukhiqiza ama-nanocarbons kazibuthe kuma-precursors kawoyela wesundu aluhlaza kusetshenziswa i-arc kagesi kusetshenziswa i-oven microwave.Ubuningi bamafutha esundu kufanele bubonakale emikhiqizweni emisha nasekusetshenzisweni kwayo.Le ndlela entsha yokucwenga uwoyela wesundu ingasiza ekufukuleni umkhakha wezomnotho futhi ibe omunye umthombo wemali engenayo kubakhiqizi bakawoyela wesundu, ikakhulukazi ethintekile amasimu kawoyela wesundu abalimi abancane.Ngokocwaningo lwabalimi abancane base-Afrika olwenziwa ngu-Ayompe et al., abalimi abancane bathola imali eningi kuphela uma begawula amaqoqo ezithelo ezintsha ngokwabo futhi badayisele amafutha esundu aluhlaza kunokuba bawadayisele abathengisi, okuwumsebenzi obizayo futhi oyisicefe47.Ngasikhathi sinye, ukwanda kokuvalwa kwefekthri ngenxa ye-COVID-19 kuthinte imikhiqizo esekelwe kuwoyela wesundu.Kuyathakazelisa ukuthi njengoba amakhaya amaningi ekwazi ukuthola ohhavini be-microwave futhi indlela ehlongozwayo kulolu cwaningo ingathathwa njengengenzeka futhi ithengeke, ukukhiqizwa kwe-MNC kungabhekwa njengenye indlela esikhundleni samasimu kawoyela wesundu amancane.Ngaleso sikhathi, ngezinga elikhulu, izinkampani zingatshala imali kuma-reactor amakhulu ukuze zikhiqize ama-TNC amakhulu.
Lolu cwaningo luhlanganisa ikakhulukazi inqubo yokuhlanganisa kusetshenziswa insimbi engagqwali njengendawo esetshenziswa ugesi isikhathi eside.Ucwaningo oluningi olujwayelekile olusebenzisa ama-microwave nama-nanocarbons luphakamisa isikhathi esamukelekile sokuhlanganiswa esiyimizuzu engama-30 noma ngaphezulu33,34.Ukuze kusekelwe umbono ongokoqobo ofinyelelekayo nonokwenzeka, lolu cwaningo lwaluhlose ukuthola ama-MNC anezikhathi zokuhlanganisa ezingaphansi kwesilinganiso.Ngesikhathi esifanayo, ucwaningo ludweba isithombe sezinga lesi-3 lokulungela ubuchwepheshe njengoba ithiyori ifakazelwa futhi isetshenziswa esikalini selabhorethri.Kamuva, i-MNCs eyaba umphumela yabonakala ngezakhiwo zayo ezingokomzimba, zamakhemikhali, nezikazibuthe.I-methylene eluhlaza okwesibhakabhaka yabe isetshenziselwe ukubonisa amandla okukhangisa we-MNCs ewumphumela.
Amafutha esundu angahluziwe atholwe kwa-Apas Balung Mill, eSawit Kinabalu Sdn.Bhd., Tawau, futhi isetshenziswa njengesandulela sekhabhoni ukuze kuhlanganiswe.Kulokhu, ucingo lwensimbi engagqwali olunobubanzi obungu-0.90 mm lusetshenziswe njenge-dielectric medium.I-Ferrocene (ukuhlanzeka okungu-99%), etholwe kwa-Sigma-Aldrich, e-USA, ikhethwe njenge-catalyst kulo msebenzi.I-Methylene eluhlaza okwesibhakabhaka (i-Bendosen, i-100 g) yaphinde yasetshenziselwa ukuhlolwa kwe-adsorption.
Kulolu cwaningo, ihhavini le-microwave yasendlini (i-Panasonic: SAM-MG23K3513GK) yaguqulwa yaba i-reactor ye-microwave.Kwenziwa izimbobo ezintathu engxenyeni engenhla yehhavini ye-microwave yokungena nokuphuma kwegesi kanye ne-thermocouple.Ama-thermocouple probes afakwe amashubhu e-ceramic futhi afakwa ngaphansi kwezimo ezifanayo zokuhlola ngakunye ukuvimbela izingozi.Phakathi naleso sikhathi, i-reactor yengilazi ye-borosilicate enesivalo esinezimbobo ezintathu yayisetshenziselwa ukufaka amasampula kanye noqhoqhoqho.Umdwebo oyisikimu we-reactor ye-microwave ungabhekiselwa kuwo ku-Supplementary Figure 1.
Kusetshenziswa uwoyela wesundu ongahluziwe njengesandulela sekhabhoni kanye ne-ferrocene njenge-catalyst, ama-nanocarbon kazibuthe ahlanganiswa.Cishe u-5% ngesisindo se-ferrocene catalyst yalungiswa ngendlela ye-slurry catalyst.I-Ferrocene ixutshwe no-20 ml wamafutha esundu ongahluziwe ku-60 rpm imizuzu engu-30.Ingxube yabe idluliselwa ku-alumina crucible, futhi ucingo lwensimbi engagqwali ubude obungu-30 cm lwagoqwa futhi lwabekwa lwabheka ngaphakathi kwe-crucible.Faka i-alumina crucible kureactor yengilazi futhi uyivikele ngokuphephile ngaphakathi kuhhavini we-microwave ngesivalo sengilazi esivaliwe.I-Nitrojeni yapheshulwa ekamelweni imizuzu engu-5 ngaphambi kokuqala kokusabela ukuze kukhishwe umoya ongafuneki ekamelweni.Amandla e-microwave akhushulwe afinyelela ku-800W ngoba lawa amandla aphezulu e-microwave angagcina isiqalo esihle se-arc.Ngakho-ke, lokhu kungase kube nomthelela ekwakhiweni kwezimo ezivumayo zokusabela kokwenziwa.Ngasikhathi sinye, leli futhi ububanzi bamandla asetshenziswa kakhulu kuma-watts wokusabela kwe-microwave fusion48,49.Ingxube yashiswa imizuzu eyi-10, engu-15 noma engu-20 ngesikhathi sokusabela.Ngemva kokuphothulwa kokusabela, i-reactor kanye ne-microwave kwapholiswa ngokwemvelo ekamelweni lokushisa.Umkhiqizo wokugcina ku-alumina crucible kwakuyimvula emnyama enezintambo ze-helical.
Imvula emnyama yaqoqwa futhi yagezwa izikhathi eziningana ngokushintshana nge-ethanol, isopropanol (70%) namanzi acwecwe.Ngemuva kokugeza nokuhlanza, umkhiqizo uyomiswa ngobusuku obungama-80 ° C kuhhavini evamile ukuze uhwamulise ukungcola okungafuneki.Umkhiqizo wabe usuqoqwa ukuze uhlaziywe.Amasampula anelebula i-MNC10, MNC15, kanye ne-MNC20 asetshenziswe ukuze kuhlanganiswe ama-nanocarbons kazibuthe amaminithi angu-10, amaminithi angu-15, kanye namaminithi angu-20.
Qaphela i-MNC morphology ngesibonakhulu se-electron esikhipha insimu noma i-FESEM (imodeli ye-Zeiss Auriga) ekukhuliseni okungu-100 kuya ku-150 kX.Ngesikhathi esifanayo, ukwakheka okuyisisekelo kwahlaziywa nge-X-ray spectroscopy (EDS) ye-energy-dispersive X-ray.Ukuhlaziywa kwe-EMF kwenziwa ebangeni lokusebenza lika-2.8 mm kanye ne-voltage esheshayo ye-1 kV.Indawo ethile engaphezulu kanye namanani we-MNC pore akalwe ngendlela ye-Brunauer-Emmett-Teller (BET), okuhlanganisa i-adsorption-desorption isotherm ye-N2 ku-77 K. Ukuhlaziywa kwenziwa kusetshenziswa imitha yendawo eyimodeli (MICROMERITIC ASAP 2020) .
I-crystallinity kanye nesigaba sama-nanocarbons azibuthe anqunywe yi-X-ray powder diffraction noma i-XRD (Burker D8 Advance) ku-λ = 0.154 nm.Ama-Diffractograms aqoshwa phakathi kuka-2θ = 5 no-85 ° ngenani lokuskena le-2 ° min-1.Ukwengeza, ukwakheka kwamakhemikhali e-MNCs kwaphenywa kusetshenziswa i-Fourier transform infrared spectroscopy (FTIR).Ukuhlaziya kwenziwa kusetshenziswa i-Perkin Elmer FTIR-Spectrum 400 enezivinini zokuskena ezisukela ku-4000 kuya ku-400 cm-1.Ekutadisheni izici zesakhiwo sama-nanocarbons azibuthe, i-Raman spectroscopy yenziwa kusetshenziswa i-neodymium-doped laser (532 nm) ku-U-RAMAN spectroscopy enomgomo ongu-100X.
I-magnetometer edlidlizayo noma i-VSM (uchungechunge lweLake Shore 7400) yasetshenziswa ukukala ukugcwala kukazibuthe kwe-iron oxide kuma-MNCs.Kusetshenziswe indawo kazibuthe engaba ngu-8 kOe futhi kwatholakala amaphuzu angama-200.
Lapho kufundwa amandla e-MNCs njengama-adsorbents ekuhlolweni kwe-adsorption, udayi we-cationic we-methylene blue (MB) wasetshenziswa.Ama-MNCs (20 mg) engezwe ku-20 ml wesisombululo esinamanzi se-methylene eluhlaza okwesibhakabhaka nokugxila okujwayelekile ebangeni lika-5-20 mg/L50.I-pH yesisombululo isethwe ku-pH engathathi hlangothi engu-7 kulo lonke ucwaningo.Isixazululo sashukunyiswa ngomshini ngo-150 rpm kanye no-303.15 K ku-rotary shaker (Lab Companion: SI-300R).Ama-MNC abe esehlukaniswa kusetshenziswa uzibuthe.Sebenzisa i-spectrophotometer ebonakalayo ye-UV (Varian Cary 50 UV-Vis Spectrophotometer) ukuze ubuke ukugxiliswa kwesisombululo se-MB ngaphambi nangemuva kokuhlolwa kwe-adsorption, futhi ubhekisele kwijika elijwayelekile le-methylene eluhlaza okwesibhakabhaka kubude begagasi obukhulu obungu-664 nm.Ukuhlolwa kuphindwe kathathu futhi inani elimaphakathi lanikezwa.Ukukhishwa kwe-MG esixazululweni kubalwe kusetshenziswa isibalo esijwayelekile senani le-MC elikhangisiwe ngokulingana qe kanye nephesenti lokususwa %.
Izivivinyo ze-adsorption isotherm nazo zenziwa ngokushukumisa ukugxila okuhlukahlukene (5-20 mg/l) kwezixazululo ze-MG kanye no-20 mg we-adsorbent ekushiseni okungaguquki okungu-293.15 K. mg kuwo wonke ama-MNCs.
I-iron kanye nekhabhoni kazibuthe kuye kwafundwa kabanzi emashumini ambalwa eminyaka adlule.Lezi zinto ezisebenza kukazibuthe ezisuselwa kukhabhoni ziheha ukunaka okwandayo ngenxa yezakhiwo zazo ezinhle kakhulu zikagesi, okuholela ekusetshenzisweni kwezobuchwepheshe okuhlukahlukene, ikakhulukazi ezintweni zikagesi kanye nokwelashwa kwamanzi.Kulolu cwaningo, ama-nanocarbons ahlanganiswa ngokuqhekeka ama-hydrocarbon kuwoyela wesundu ongahluziwe kusetshenziswa ukukhishwa kwe-microwave.Ukuhlanganiswa kwenziwa ngezikhathi ezihlukene, ukusuka kumaminithi angu-10 kuye kwangu-20, ngesilinganiso esinqunyiwe (5:1) sesandulela kanye ne-catalyst, kusetshenziswa umqoqi wamanje wensimbi (i-SS esontekile) kanye ne-inert ingxenye (umoya ongathandeki ohlanzwa nge-nitrogen endaweni ukuqala kokuhlolwa).Amadiphozithi e-carbonaceous avelayo asesimweni sempushana eqinile emnyama, njengoba kuboniswe ku-Supplementary Fig. 2a.Izivuno zekhabhoni ezincishisiwe zazicishe zibe ngu-5.57%, 8.21%, no-11.67% ngezikhathi zokuhlanganisa imizuzu eyi-10, imizuzu eyi-15, nemizuzu engama-20, ngokulandelana.Lesi simo siphakamisa ukuthi izikhathi ezinde zokuhlanganisa zifaka isandla ekuvuneni okuphezulu51—isivuno esiphansi, cishe ngenxa yezikhathi ezimfushane zokusabela kanye nomsebenzi ophansi we-catalyst.
Khonamanjalo, isiqephu sezinga lokushisa elihlanganisiwe ngokumelene nesikhathi sama-nanocarbons atholiwe singabhekiselwa kuso Emfanekisweni Owengeziwe 2b.Amazinga okushisa aphezulu atholwe ku-MNC10, MNC15 kanye ne-MNC20 abengu-190.9°C, 434.5°C no-472°C, ngokulandelana.Ejikeni ngalinye, kungase kubonakale umqansa, okubonisa ukunyuka okuqhubekayo kwezinga lokushisa ngaphakathi kwe-reactor ngenxa yokushisa okukhiqizwa phakathi ne-arc yensimbi.Lokhu kungabonwa kumaminithi angu-0–2, amaminithi angu-0–5, kanye nemizuzu engu-0–8 ye-MNC10, MNC15, kanye ne-MNC20, ngokulandelana.Ngemva kokufinyelela endaweni ethile, umthambeka uyaqhubeka uhambela ezingeni lokushisa eliphakeme kakhulu, futhi umthambeka uba ngokulinganisela.
I-Field emission scanning electron microscopy (FESEM) yasetshenziswa ukubuka isimo sendawo samasampula e-MNC.Njengoba kuboniswe emkhiwaneni.1, ama-nanocarbons azibuthe anesakhiwo se-morphological esihluke kancane ngesikhathi esihlukile sokuhlanganiswa.Izithombe ze-FESEM MNC10 kufig.I-1a,b ibonisa ukuthi ukwakheka kwama-carbon spheres kuqukethe ama-micro- and nanospheres abambene futhi anamathiselwe ngenxa yokushuba okuphezulu kwendawo.Ngesikhathi esifanayo, ukuba khona kwamandla e-van der Waals kuholela ekuhlanganisweni kwama-carbon spheres52.Ukwanda kwesikhathi sokuhlanganiswa kubangele osayizi abancane kanye nokwenyuka kwenani lama-sphere ngenxa yokusabela kokuqhekeka okude.Emkhiwaneni.I-1c ibonisa ukuthi i-MNC15 inomumo ocishe ube yindilinga ophelele.Kodwa-ke, ama-sphere ahlanganisiwe asengakha ama-mesopores, angase abe iziza ezinhle ze-methylene blue adsorption.Ekukhulisweni okuphezulu kwezikhathi eziyi-15,000 ku-Fig. I-1d ngaphezulu kwama-carbon spheres ingabonwa ihlanganiswe nosayizi omaphakathi ongu-20.38 nm.
Izithombe ze-FESEM zama-nanocarbons ahlanganisiwe ngemva kwamaminithi angu-10 (a, b), amaminithi angu-15 (c, d) kanye namaminithi angu-20 (e–g) ku-7000 kanye nezikhathi ezingu-15000 zokukhulisa.
Emkhiwaneni.I-1e–g MNC20 ibonisa ukuthuthukiswa kwezimbotshana ezinezindilinga ezincane endaweni yekhabhoni kazibuthe futhi ihlanganise kabusha imo ye-carbon activated magnetic53.Izimbotshana ezinobubanzi obuhlukene nobubanzi zitholakala ngokungahleliwe phezu kwekhabhoni kazibuthe.Ngakho-ke, lokhu kungase kuchaze ukuthi kungani i-MNC20 ibonise indawo enkulu kanye nevolumu yembotshana njengoba kuboniswa ukuhlaziywa kwe-BET, njengoba kwakheka izimbotshana eziningi endaweni yayo kunangezinye izikhathi zokwenziwa.Ama-Micrographs athathwe ekukhulisweni okuphezulu kwezikhathi ze-15,000 abonise ubukhulu bezinhlayiya ezingafani kanye nokuma okungavamile, njengoba kuboniswe ku-Fig. 1g.Lapho isikhathi sokukhula senyuswa saba yimizuzu engama-20, kwakheka ama-agglomerated spheres.
Ngokuthakazelisayo, ama-carbon flakes asontekile nawo atholakala endaweni efanayo.Ububanzi bezinhlayiya behlukahluka kusuka ku-5.18 kuya ku-96.36 nm.Lokhu kwakheka kungase kube ngenxa yokuvela kwe-nucleation ehlukile, eyenziwa lula ukushisa okuphezulu nama-microwaves.Usayizi we-sphere obaliwe wama-MNC alungisiwe wenza isilinganiso esingu-20.38 nm ku-MNC10, 24.80 nm ku-MNC15, kanye no-31.04 nm ku-MNC20.Ukusatshalaliswa kosayizi wama-sphere kukhonjisiwe ku-fig eyengeziwe.3.
Umfanekiso ongeziwe wesi-4 ubonisa izifinyezo ze-EDS zokwakheka kwezinto eziyisisekelo ze-MNC10, MNC15, kanye ne-MNC20, ngokulandelana.Ngokusho kwe-spectra, kwaphawulwa ukuthi i-nanocarbon ngayinye iqukethe inani elihlukile le-C, O, ne-Fe.Lokhu kungenxa yezinhlobonhlobo ze-oxidation nokuqhekeka okwenzeka ngesikhathi esengeziwe sokuhlanganiswa.Inani elikhulu lika-C kukholakala ukuthi livela ku-carbon precursor, uwoyela wesundu ongahluziwe.Phakathi naleso sikhathi, iphesenti eliphansi lika-O libangelwa inqubo ye-oxidation ngesikhathi sokuhlanganiswa.Ngaso leso sikhathi, i-Fe ibhekwa yi-iron oxide efakwe endaweni ye-nanocarbon ngemva kokubola kwe-ferrocene.Ukwengeza, Umfanekiso Owengeziwe 5a–c ubonisa ukudwetshwa kwezakhi ze-MNC10, MNC15, kanye ne-MNC20.Ngokusekelwe kumephu eyisisekelo, kwaqashelwa ukuthi i-Fe isatshalaliswe kahle endaweni ye-MNC.
Ukuhlaziywa kwe-nitrogen adsorption-desorption kunikeza ulwazi mayelana nendlela ye-adsorption kanye nesakhiwo esinezimbotshana sezinto ezibonakalayo.I-N2 adsorption isotherms kanye namagrafu obuso be-MNC BET akhonjisiwe kumakhiwane.2. Ngokusekelwe ezithombeni ze-FESEM, ukuziphatha kokukhangiswa kulindeleke ukuthi kubonise inhlanganisela yezakhiwo ze-microporous kanye ne-mesoporous ngenxa yokuhlanganisa.Nokho, igrafu ku-Fig. 2 ibonisa ukuthi i-adsorbent ifana nohlobo lwe-IV isotherm kanye nohlobo lwe-H2 hysteresis loop ye-IUPAC55.Lolu hlobo lwe-isotherm luvame ukufana nolwezinto ze-mesoporous.Ukuziphatha kwe-adsorption kwama-mesopores kuvame ukunqunywa ukusebenzisana kwe-adsorption-adsorption reactions nama-molecule ento efingqiwe.Ama-isotherm e-adsorption anomumo ka-S noma amise okuka-S ngokuvamile abangelwa i-adsorption yesendlalelo-esiningi elandelwa into lapho igesi ijiya ibe yisigaba soketshezi ezimbotsheni ngezingcindezi ezingaphansi kokucindezela kokugcwala koketshezi oluyinqwaba, okwaziwa ngokuthi ukufingqa kwembotshana 56. Ukufiphala kwama-capillary ezimbotsheni kwenzeka ngengcindezi ehlobene (p/po) engaphezu kuka-0.50.Ngaleso sikhathi, ukwakheka kwembotshana eyinkimbinkimbi kukhombisa i-H2-type hysteresis, okubangelwa ukuxhuma izimbotshana noma ukuvuza kuhlu oluncane lwezimbotshana.
Imingcele ebonakalayo yendawo etholwe ekuhlolweni kwe-BET iboniswa kuThebula 1. Indawo ye-BET kanye nenani lembobo eliphelele likhuphuke kakhulu ngokukhula kwesikhathi sokuhlanganiswa.Isilinganiso sosayizi wezimbotshana ze-MNC10, MNC15, kanye ne-MNC20 zingu-7.2779 nm, 7.6275 nm, kanye no-7.8223 nm, ngokulandelana.Ngokwezincomo ze-IUPAC, lezi zimbotshana ezimaphakathi zingahlukaniswa njengezisetshenziswa ze-mesoporous.Isakhiwo se-mesoporous singenza i-methylene eluhlaza okwesibhakabhaka ingene kalula futhi ikhangeke yi-MNC57.I-Maximum Synthesis Time (MNC20) ibonise indawo ephezulu kakhulu, ilandelwa yi-MNC15 ne-MNC10.Indawo ephakeme ye-BET ingathuthukisa ukusebenza kwe-adsorption njengoba amasayithi amaningi e-surfactant etholakala.
Amaphethini we-X-ray diffraction we-MNCs ahlanganisiwe aboniswa ku-Fig. 3. Emazingeni okushisa aphezulu, i-ferrocene iphinda iqhekeke futhi yakhe i-iron oxide.Emkhiwaneni.I-3a ibonisa iphethini ye-XRD ye-MNC10.Ibonisa iziqongo ezimbili ku-2θ, 43.0° naku-62.32°, ezinikezwe i-ɣ-Fe2O3 (JCPDS #39–1346).Ngesikhathi esifanayo, i-Fe3O4 inenani eliphakeme elicindezelwe ku-2θ: 35.27°.Ngakolunye uhlangothi, kuphethini ye-MHC15 ye-diffraction ku-Fig. 3b ibonisa iziqongo ezintsha, okungenzeka ukuthi zihlotshaniswa nokwanda kwezinga lokushisa nesikhathi sokuhlanganiswa.Nakuba isiqongo esingu-2θ: 26.202° singashubi kangako, iphethini yokuhlukanisa ihambisana nefayela le-graphite JCPDS (JCPDS #75–1621), okubonisa ukuba khona kwamakristalu e-graphite ngaphakathi kwe-nanocarbon.Lesi siqongo alikho ku-MNC10, okungenzeka ngenxa yezinga lokushisa eliphansi le-arc ngesikhathi sokuhlanganiswa.Ku-2θ kuneziqongo zesikhathi ezintathu: 30.082°, 35.502°, 57.422° okubangelwa ku-Fe3O4.Iphinde ibonise iziqongo ezimbili ezibonisa ukuba khona kwe-ɣ-Fe2O3 ku-2θ: 43.102° naku-62.632°.Ku-MNC ehlanganiselwe amaminithi angu-20 (MNC20), njengoba kuboniswe ku-Fig. 3c, iphethini efanayo yokuhlukanisa ingabonwa ku-MNK15.Ukuphakama kwesithombe ku-26.382 ° kungabonakala futhi ku-MNC20.Iziqongo ezintathu ezicijile eziboniswe ku-2θ: 30.102°, 35.612°, 57.402° eze-Fe3O4.Ngaphezu kwalokho, ukuba khona kwe-ε-Fe2O3 kuboniswa ku-2θ: 42.972° naku-62.61.Ukuba khona kwezinhlanganisela ze-iron oxide ku-MNCs ewumphumela kungaba nomthelela omuhle ekhonweni lokukhangisa i-methylene eluhlaza okwesibhakabhaka ngokuzayo.
Izici zebhondi yamakhemikhali kumasampuli we-MNC ne-CPO zinqunywe ku-FTIR reflectance spectra ku-Supplementary Figure 6. Ekuqaleni, iziqongo eziyisithupha ezibalulekile zikawoyela wesundu ongahluziwe zazimele izingxenye zamakhemikhali ezine ezihlukene njengoba kuchazwe kuThebula Lokwengeza 1. Iziqongo eziyisisekelo ezikhonjwe ku-CPO. kungu-2913.81 cm-1, 2840 cm-1 kanye no-1463.34 cm-1, abhekisela ekudlidlizeni okwelula kwe-CH kwama-alkanes namanye amaqembu e-aliphatic CH2 noma CH3.Amahlathi aphakeme ahlonziwe angu-1740.85 cm-1 kanye no-1160.83 cm-1.Ukuphakama okungu-1740.85 cm-1 kuyibhondi ye-C=O enwetshwe yi-ester carbonyl yeqembu elisebenzayo le-triglyceride.Phakathi naleso sikhathi, ukuphakama ku-1160.83 cm-1 kuwuphawu lweqembu le-ester elinwetshiwe le-CO58.59.Ngaleso sikhathi, inani eliphakeme ku-813.54 cm-1 liwuphawu lweqembu le-alkane.
Ngakho-ke, ezinye iziqongo zokumunca kuwoyela wesundu ongahluziwe zanyamalala njengoba isikhathi sokuhlanganisa sikhula.Ukuphakama okungu-2913.81 cm-1 kanye no-2840 cm-1 kusengabonwa ku-MNC10, kodwa kuyathakazelisa ukuthi ku-MNC15 kanye ne-MNC20 iziqongo zivamise ukunyamalala ngenxa ye-oxidation.Ngaleso sikhathi, ukuhlaziya kwe-FTIR kwama-nanocarbon kazibuthe kwembule iziqongo zokumunca ezintsha ezimele amaqembu amahlanu ahlukene asebenzayo we-MNC10-20.Lezi ziqongo ziphinde zifakwe kuhlu kuThebula Lokwengeza 1. Ukuphakama okungu-2325.91 cm-1 kuwukunwebeka kwe-CH oku-asymmetric kweqembu le-aliphatic le-CH360.Ukuphakama okungu-1463.34-1443.47 cm-1 kubonisa ukugoba kwe-CH2 no-CH kwamaqembu e-aliphatic njengamafutha esundu, kodwa ukuphakama kuqala ukuncipha ngokuhamba kwesikhathi.Ukuphakama okungu-813.54–875.35 cm–1 kuwuphawu lweqembu elinephunga elimnandi le-CH-alkane.
Khonamanjalo, iziqongo ku-2101.74 cm-1 kanye no-1589.18 cm-1 zimelela amabhondi angu-CC 61 akha i-C=C alkyne namasongo anuka kamnandi, ngokulandelana.Ukuphakama okuncane okungu-1695.15 cm-1 kubonisa isibopho se-C=O samafutha amahhala avela eqenjini le-carbonyl.Itholakala ku-CPO carbonyl kanye ne-ferrocene ngesikhathi sokuhlanganiswa.Iziqongo ezisanda kwakhiwa kububanzi obusuka ku-539.04 ukuya ku-588.48 cm-1 ngezebhondi yokudlidliza ye-Fe-O ye-ferrocene.Ngokusekelwe eziqongweni eziboniswe kuMfanekiso Ongezelelwe 4, kungabonakala ukuthi isikhathi sokuhlanganiswa singanciphisa iziqongo ezimbalwa kanye nokubopha kabusha ama-nanocarbon kazibuthe.
Ukuhlaziywa kwe-Spectroscopic kokuhlakazeka kwe-Raman kwama-nanocarbon kazibuthe atholwe ngezikhathi ezihlukene zokwenziwa kusetshenziswa i-laser yesigameko enobude beza beza obungu-514 nm kuboniswa kuMfanekiso 4. Yonke i-spectra ye-MNC10, MNC15 kanye ne-MNC20 iqukethe amabhendi amabili aqinile ahlotshaniswa ne-sp3 carbon ephansi, ngokuvamile. kutholakala kuma-nanographite crystallites anokukhubazeka ezindleleni zokudlidliza zezinhlobo ze-carbon sp262.Isiqongo sokuqala, esitholakala esifundeni se-1333-1354 cm-1, simelela i-D band, engafaneleki i-graphite efanelekile futhi ehambisana nokuphazamiseka kwesakhiwo nokunye ukungcola63,64.Isiqongo sesibili esibaluleke kakhulu esizungeze i-1537-1595 cm-1 sivela ekunwetshweni kwebhondi yendiza noma i-crystalline futhi yayala amafomu e-graphite.Kodwa-ke, inani eliphakeme lishintshe cishe ngo-10 cm-1 uma liqhathaniswa nebhande le-graphite G, okubonisa ukuthi ama-MNC anohlelo oluphansi lokupakisha amashidi kanye nesakhiwo esinesici.Ukuqina okuhlobene kwamabhendi e-D kanye no-G (ID/IG) asetshenziselwa ukuhlola ukuhlanzeka kwamasampula e-crystallites nama-graphite.Ngokusho kokuhlaziywa kwe-Raman spectroscopic, wonke ama-MNC abe namanani e-ID/IG ebangeni lika-0.98–0.99, okubonisa ukukhubazeka kwesakhiwo ngenxa ye-Sp3 hybridization.Lesi simo singachaza ukuba khona kweziqongo eziqine kancane ze-2θ ku-spectra ye-XPA: 26.20° ku-MNK15 kanye no-26.28° ku-MNK20, njengoba kuboniswe ku-Fig. 4, eyabelwe isiqongo segraphite kufayela le-JCPDS.Izilinganiso ze-ID/IG MNC ezitholwe kulo msebenzi zisebangeni lamanye ama-nanocarbon kazibuthe, isibonelo, i-0.85–1.03 yendlela ye-hydrothermal kanye ne-0.78–0.9665.66 yendlela ye-pyrolytic.Ngakho-ke, lesi silinganiso sibonisa ukuthi indlela yamanje yokwenziwa ingasetshenziswa kabanzi.
Izici kazibuthe ze-MNCs zahlaziywa kusetshenziswa i-magnetometer edlidlizayo.I-hysteresis ewumphumela iboniswa ku-Fig.5.Njengomthetho, ama-MNC athola uzibuthe wawo ku-ferrocene ngesikhathi sokuhlanganiswa.Lezi zakhiwo zikazibuthe ezengeziwe zingase zikhulise umthamo wokukhangisa wama-nanocarbons esikhathini esizayo.Njengoba kukhonjisiwe kuMfanekiso 5, amasampula angakhonjwa njengezinto ze-superparamagnetic.Ngokusho kuka-Wahajuddin & Arora67, isimo se-superparamagnetic ukuthi isampula ifakwe uzibuthe ku-saturation magnetization (MS) lapho kusetshenziswa inkambu yamagnetic yangaphandle.Kamuva, ukusebenzisana kukazibuthe okusele akusaveli kumasampuli67.Kuyaphawuleka ukuthi i-saturation magnetization iyanda ngesikhathi sokuhlanganiswa.Kuyathakazelisa ukuthi i-MNC15 inokugcwaliswa kazibuthe okuphezulu kakhulu ngoba ukwakheka kukazibuthe okuqinile (magnetization) kungabangelwa isikhathi sokuhlanganisa esilungile phambi kukazibuthe wangaphandle.Lokhu kungase kube ngenxa yokuba khona kwe-Fe3O4, enezakhiwo ezingcono kazibuthe uma kuqhathaniswa namanye ama-iron oxide afana ne-ɣ-Fe2O.Ukuhleleka kwe-adsorption moment of saturation per unit mass of MNCs ngu-MNC15>MNC10>MNC20.Amapharamitha kazibuthe atholakala kuthebula.2.
Inani eliphansi lokugcwaliswa kazibuthe uma usebenzisa omazibuthe abavamile ekuhlukaniseni kazibuthe licishe libe ngu-16.3 emu g-1.Ikhono le-MNCs lokususa ukungcola okufana nodayi endaweni yasemanzini kanye nokususwa kalula kwama-MNC kube yizici ezengeziwe zama-nanocarbons atholiwe.Ucwaningo luye lwabonisa ukuthi ukugcwaliswa kazibuthe kwe-LSM kuthathwa njengokuphezulu.Ngakho-ke, wonke amasampula afinyelele amanani okugcwala kazibuthe ngaphezu kokwanele inqubo yokuhlukanisa kazibuthe.
Muva nje, imichilo yensimbi noma izintambo zihehe ukunakwa njengama-catalyst noma ama-dielectrics ezinqubweni zokuhlanganisa ama-microwave.Ukusabela kwe-microwave kwezinsimbi kubangela izinga lokushisa eliphezulu noma ukusabela ngaphakathi kwe-reactor.Lolu cwaningo luthi ithiphu kanye nentambo yensimbi engagqwali egoqiwe (egoqiwe) kusiza ukukhishwa kwe-microwave kanye nokushisisa kwensimbi.Insimbi engagqwali isho ukuhwalala ekugcineni, okuholela kumanani aphezulu wokuminyana kokushaja kwendawo kanye nenkundla kagesi yangaphandle.Uma ukushaja sekuzuze amandla e-kinetic anele, izinhlayiya ezishajwayo zizogxuma ziphume ensimbi engagqwali, zenze indawo ezungezile ibe ionini, ikhiqize okuphumayo noma inhlansi 68.Ukukhishwa kwensimbi kwenza umnikelo obalulekile ekuxazululeni ukusabela kokuqhekeka okuhambisana nezindawo ezishisayo ezishisayo.Ngokusho kwemephu yezinga lokushisa ku-Supplementary Fig. 2b, izinga lokushisa likhuphuka ngokushesha, okubonisa ukuba khona kwezindawo ezishisayo ezisezingeni eliphezulu ngaphezu kokukhipha okunamandla.
Kulokhu, umphumela wokushisa uyabonakala, njengoba ama-electron aboshwe kancane anganyakaza futhi agxilise phezulu kanye ne-tip69.Lapho insimbi engagqwali ilimala, indawo enkulu yensimbi esesixazululweni isiza ukunxenxa imisinga ye-eddy ebusweni bento futhi igcine umphumela wokushisa.Lesi simo sisiza ngempumelelo ukusika amaketanga ekhabhoni amade e-CPO kanye ne-ferrocene ne-ferrocene.Njengoba kuboniswe ku-Supplementary Fig. 2b, izinga lokushisa elihlala njalo libonisa ukuthi umphumela wokushisa ofanayo ubonwa kwisixazululo.
Indlela ehlongozwayo yokwakhiwa kwama-MNC ikhonjisiwe Emfanekisweni Owengeziwe 7. Amaketanga ekhabhoni amade e-CPO kanye ne-ferrocene aqala ukuqhekeka lapho izinga lokushisa liphezulu.Amafutha aphuka ukuze akhe ama-hydrocarbon ahlukanisiwe aba izandulela zekhabhoni ezaziwa ngokuthi ama-globule esithombeni se-FESEM MNC1070.Ngenxa yamandla emvelo kanye nengcindezi engu-71 ezimeni zasemkhathini.Ngesikhathi esifanayo, i-ferrocene nayo iyaqhekeka, yakhe i-catalyst evela kuma-athomu e-carbon afakwe ku-Fe.I-nucleation esheshayo ibe seyenzeka futhi i-carbon core i-oxidize yakhe ungqimba lwekhabhoni ye-amorphous kanye ne-graphic ngaphezulu komnyombo.Njengoba isikhathi sikhula, ubukhulu be-sphere buba nembayo futhi bufane.Ngaso leso sikhathi, amandla akhona e-van der Waals nawo aholela ekuhlanganisweni kwama-spheres52.Ngesikhathi sokunciphisa ama-Fe ions ku-Fe3O4 kanye ne-ɣ-Fe2O3 (ngokokuhlaziywa kwesigaba se-X-ray), izinhlobo ezihlukahlukene ze-iron oxides zakhiwa phezu kwama-nanocarbons, okuholela ekwakhekeni kwama-nanocarbons kazibuthe.Imephu ye-EDS ibonise ukuthi ama-athomu e-Fe asabalaliswe ngokuqinile phezu kwendawo ye-MNC, njengoba kukhonjisiwe kokuthi Izibalo Ezingeziwe 5a-c.
Umehluko wukuthi ngesikhathi sokuhlanganiswa semizuzu engama-20, ukuhlangana kwekhabhoni kwenzeka.Kwakha izimbotshana ezinkudlwana ebusweni be-MNCs, okuphakamisa ukuthi ama-MNC angabhekwa njengekhabhoni ecushiwe, njengoba kuboniswe kuzithombe ze-FESEM ku-Fig. 1e–g.Lo mehluko kumasayizi wembotshana ungase uhlobane nomnikelo we-iron oxide ovela ku-ferrocene.Ngesikhathi esifanayo, ngenxa yokushisa okuphezulu okufinyelelwe, kunezilinganiso ezikhubazekile.Ama-nanocarbons azibuthe akhombisa ama-morphology ahlukene ngezikhathi ezihlukene zokuhlanganisa.Ama-nanocarbons maningi amathuba okuthi enze izimo eziyindilinga ezinezikhathi ezimfushane zokuhlanganisa.Ngesikhathi esifanayo, ama-pores nezikali zifinyeleleka, nakuba umehluko ngesikhathi sokuhlanganiswa ungaphakathi kwemizuzu engu-5 kuphela.
Ama-nanocarbons azibuthe angasusa ukungcola endaweni ehlala emanzini.Ikhono labo lokususwa kalula ngemva kokusetshenziswa kuyisici esengeziwe sokusebenzisa ama-nanocarbons atholakala kulo msebenzi njengama-adsorbents.Ekutadisheni izici ze-adsorption zama-nanocarbon kazibuthe, siphenye ikhono le-MNCs lokususa umbala wezixazululo ze-methylene blue (MB) ngo-30°C ngaphandle kokulungiswa kwe-pH.Ucwaningo oluningana luphethe ngokuthi ukusebenza kwezinto ezimunca ikhabhoni ebangeni lokushisa elingu-25–40 °C alidlali indima ebalulekile ekunqumeni ukususwa kwe-MC.Nakuba amanani e-pH eyeqisayo edlala indima ebalulekile, amanani angakha phezu kwamaqembu asebenzayo, okuholela ekuphazanyisweni kokuxhumana kwe-adsorbate-adsorbent futhi kuthinte i-adsorption.Ngakho-ke, izimo ezingenhla zikhethiwe kulolu cwaningo kucatshangelwa lezi zimo kanye nesidingo sokwelashwa okujwayelekile kwamanzi angcolile.
Kulo msebenzi, ukuhlolwa kwe-batch adsorption kwenziwa ngokungeza u-20 mg we-MNCs ku-20 ml wesisombululo esinamanzi se-methylene eluhlaza okwesibhakabhaka nokugxilisa okujwayelekile okuhlukahlukene kokuqala (5-20 ppm) ngesikhathi sokuxhumana esinqunyiwe60.Umfanekiso ongeziwe wesi-8 ubonisa isimo sokugxila okuhlukahlukene (5-20 ppm) sezixazululo eziluhlaza okwesibhakabhaka ze-methylene ngaphambi nangemva kokwelashwa nge-MNC10, MNC15, kanye ne-MNC20.Uma usebenzisa ama-MNC ahlukahlukene, ileveli yombala yezixazululo ze-MB yehla.Kuyathakazelisa ukuthi kutholwe ukuthi i-MNC20 iguqule kalula izixazululo ze-MB ekuhlanganiseni okungu-5 ppm.Ngaleso sikhathi, i-MNC20 iphinde yehlisa izinga lombala lesixazululo se-MB uma kuqhathaniswa namanye ama-MNC.I-spectrum ebonakalayo ye-UV ye-MNC10-20 ikhonjiswe ku-Supplementary Figure 9. Phakathi naleso sikhathi, izinga lokususa nolwazi lwe-adsorption luboniswa kuMfanekiso 9. 6 nakuthebula lesi-3, ngokulandelana.
Iziqongo ezinamandla ze-methylene blue zingatholakala ku-664 nm naku-600 nm.Njengomthetho, ukuqina kwesiqongo kuncipha kancane kancane ngokuncipha kokugxila kokuqala kwesixazululo se-MG.Emfanekisweni owengeziwe we-9a ubonisa i-spectra ebonakalayo ye-UV yezixazululo ze-MB zokugxila okuhlukahlukene ngemva kokwelashwa nge-MNC10, okushintshe kancane nje ukuqina kweziqongo.Ngakolunye uhlangothi, iziqongo zokumunca zezixazululo ze-MB zehle kakhulu ngemva kokwelashwa nge-MNC15 kanye ne-MNC20, njengoba kuboniswe kokuthi Izibalo Ezingeziwe 9b kanye no-c, ngokulandelana.Lezi zinguquko zibonakala ngokucacile njengoba ukugxila kwesisombululo se-MG kuncipha.Nokho, izinguquko ze-spectral ezizuzwe yiwo womathathu amakhabhoni kazibuthe zazenele ukususa udayi oluhlaza okwesibhakabhaka we-methylene.
Ngokusekelwe kuThebula 3, imiphumela yenani le-MC adsorbed kanye nephesenti le-MC adsorbed kukhonjiswe ku-Fig. 3. 6. Ukukhangisa kwe-MG kukhuphuke ngokusetshenziswa kokugxilisa kokuqala okuphezulu kwawo wonke ama-MNC.Ngaleso sikhathi, iphesenti le-adsorption noma izinga lokususwa kwe-MB (MBR) libonise ukuthambekela okuphambene lapho ukugxila kokuqala kukhuphuka.Ezindaweni eziphansi zokugxila kwe-MC, amasayithi asebenzayo angahlali muntu ahlala endaweni ye-adsorbent.Njengoba ukugxiliswa kodayi kukhula, inani lezindawo ezingasebenzi ezitholakalayo zokukhangiswa kwama-molecule odayi lizokwehla.Abanye baphethe ngokuthi ngaphansi kwalezi zimo ukugcwaliswa kwezindawo ezisebenzayo ze-biosorption kuzofinyelelwa72.
Ngeshwa nge-MNC10, i-MBR yenyukile futhi yehla ngemva kwesixazululo esingu-10 ppm se-MB.Ngesikhathi esifanayo, ingxenye encane kakhulu ye-MG iyakhangiswa.Lokhu kukhombisa ukuthi i-10 ppm iwukugxilisa okungcono kakhulu kwe-MNC10 adsorption.Kuwo wonke ama-MNCs afundwe kulo msebenzi, ukuhleleka kwamakhono e-adsorption kwakungokulandelayo: MNC20 > MNC15 > MNC10, amanani aphakathi kwakungu-10.36 mg/g, 6.85 mg/g kanye no-0.71 mg/g, ukususwa okumaphakathi kwamazinga e-MG ibe ngu-87, 79%, 62.26% no-5.75%.Ngakho-ke, i-MNC20 ibonise izici ezingcono kakhulu ze-adsorption phakathi kwama-nanocarbons kazibuthe ahlanganisiwe, kucatshangelwa umthamo we-adsorption kanye ne-spectrum ebonakalayo ye-UV.Nakuba umthamo we-adsorption uphansi uma uqhathaniswa namanye ama-nanocarbons kazibuthe njenge-MWCNT composite kazibuthe (11.86 mg/g) kanye ne-halloysite nanotube-magnetic Fe3O4 nanoparticles (18.44 mg/g), lolu cwaningo aludingi ukusetshenziswa okwengeziwe kwesivuseleli.Amakhemikhali asebenza njengama-catalyst.ukuhlinzeka ngezindlela zokwenziwa ezihlanzekile nezingenzeka73,74.
Njengoba kuboniswa amanani we-SBET we-MNCs, indawo ethile ephezulu ihlinzeka ngeziza ezisebenza kakhulu zokukhangisa kwesixazululo se-MB.Lokhu kuba esinye sezici ezibalulekile zama-nanocarbons okwenziwa.Ngesikhathi esifanayo, ngenxa yobukhulu obuncane be-MNCs, isikhathi sokuhlanganiswa sifushane futhi siyamukeleka, esihambisana nezimfanelo eziyinhloko zama-adsorbents athembisayo75.Uma kuqhathaniswa nama-adsorbent avamile emvelo, ama-MNC ahlanganisiwe agcwele kazibuthe futhi angasuswa kalula esixazululweni ngaphansi kwesenzo senkundla kazibuthe yangaphandle76.Ngakho, isikhathi esidingekayo kuyo yonke inqubo yokwelashwa sincishisiwe.
Ama-isotherm e-Adsorption abalulekile ukuze uqonde inqubo ye-adsorption bese ubonisa ukuthi ama-adsorbate ahlukanisa kanjani phakathi kwezigaba eziwuketshezi neziqinile lapho ukulingana kufinyelelwa.Izibalo ze-Langmuir ne-Freundlich zisetshenziswa njengezibalo ezijwayelekile ze-isotherm, ezichaza indlela ye-adsorption, njengoba kuboniswe kuMfanekiso 7. Imodeli ye-Langmuir ibonisa kahle ukwakheka kwesendlalelo esisodwa se-adsorbate endaweni yangaphandle ye-adsorbent.Ama-Isotherms achazwa kangcono njengendawo ye-adsorption efanayo.Ngesikhathi esifanayo, i-Freundlich isotherm isho kahle kakhulu ukubamba iqhaza kwezifunda ezimbalwa ze-adsorbent namandla e-adsorption ekucindezeleni i-adsorbate endaweni engena-homogeneous.
Imodeli ye-isotherm ye-Langmuir isotherm (a–c) ne-Freundlich isotherm (d–f) ye-MNC10, MNC15 kanye ne-MNC20.
Ama-isotherm e-Adsorption ekugxilweni kwe-solute ephansi ngokuvamile angu-linear77.Ukumelwa komugqa wemodeli ye-isotherm ye-Langmuir kungavezwa ngesibalo.1 Nquma amapharamitha we-adsorption.
I-KL (l/mg) iyinhlangano ye-Langmuir engaguquki emelela ubuhlobo obubophezelayo be-MB ku-MNC.Ngaleso sikhathi, i-qmax iwumthamo omkhulu we-adsorption (mg/g), qe ukugxiliswa kwe-adsorbed kwe-MC (mg/g), futhi u-Ce ukugxilisa okulinganayo kwesixazululo se-MC.Inkulumo yomugqa yemodeli ye-Freundlich isotherm ingachazwa kanje:
Isikhathi sokuthumela: Feb-16-2023