Yog vim li cas Calcium Carbide yog qhov siv tau carbon
Calcium carbide (CaC2) yog tsim los ntawm qhov siab -kub txo cov txiv qaub nrog cov pa roj carbon nyob rau hauv lub qhov cub hluav taws xob, thiab nws tseem yog ib qho qis tshaj - tus nqi siv cov pa roj carbon monoxide pauv hauv ntau tonnage. Nws tus nqi rau graphene ntau lawm nyob rau hauv qhov reactivity ntawm carbide ion: cov pa roj carbon skeleton xav tau rau ob- qhov loj me me twb tau sib sau ua ke nyob rau hauv ib qho yooj yim ob-carbon unit, yog li cov khoom siv raw tuaj txog nrog tsawg dua ua ntej - kev kho mob ua hauj lwm tshaj li ntuj graphite los yog hydrocarbon gas, ob qho tib si yuav tsum tau purified ua ntej yuav loj hlob los yog tawg.
Kev lag luam calcium carbide yog qib feem ntau los ntawm acetylene tawm los thiab los ntawm pob loj. Cov chav kawm loj muaj xws li 0-5 hli, 5-25 hli, 25-50 hli thiab 50-80 hli. Cov chav kawm ntxhib yog ib txwm xaiv rau cov tshuaj synthesis vim tias lawv nthuav tawm thaj chaw tsawg dua rau cov dej noo nyob ib puag ncig thaum lub sijhawm khaws cia thiab xa khoom, yog li cov khoom siv tsawg dua poob rau qhov ntxov ntxov hydrolysis ua ntej nws mus txog lub reactor.
Tsib-Txoj Kev Npaj Npaj rau Ob-Dimensional Graphene
Kauj ruam ib daim ntawv cov pa roj carbon precursor. Calcium carbide thiab surfactant raug them rau hauv lub kaw agitator ntawm qhov sib piv ntawm 50: (3-6). Lub nkoj tau tuav ntawm 60-100 ° C thiab nplawm ntawm 80-120 rpm rau 5-10 feeb. Qhov nruab nrab kub thiab qis shear yog siv txhob txwm tshaj tawm, vim hais tias lub zos overheating yuav decompose cov surfactant ua ntej nws yuav stabilize lub dispersed carbide.
Kauj ruam ob ua lub template. Rectorite yog ntxuav nrog ethanol ua ntej thiab tom qab ntawd ua ke nrog cov catalyst ntawm lub rectorite-rau-catalyst huab hwm coj piv ntawm 8:(0.1-0.3). Qhov sib tov yog kho nyob rau hauv lub microwave chav ntsuas 500-600 W rau 3-5 feeb kom muab cov rectorite-txhawb catalyst template. Ethanol ntxuav yog qhov taw tes tswj tsis yog cov kauj ruam tu: cov dej adsorbed hauv av nplaum sib tw nrog cov pa roj carbon precursor thaum intercalation thiab txo cov uniformity ntawm interlayer filling.
Kauj Ruam 3 yog theem intercalation. Lub precursor los ntawm kauj ruam ib thiab lub loaded template los ntawm kauj ruam ob yog them mus rau hauv ib tug kaw dispersing tov khoom ntawm ib tug loj ratio ntawm 1:(3-4). Lub tov khoom yog tuav ntawm 60-80 ° C thiab khiav ntawm 800-1000 rpm thaum lub tshuab nqus tsev ntawm 5-10 MPa yog thov rau 10-20 feeb, kom cov precursor yog kos rau hauv thiab khaws cia rau hauv lub rectorite interlayer galleries. Cov khoom yog rectorite-interlayer carbon qhov chaw ua ntej.
Kauj ruam plaub yog theem kev loj hlob. Lub intercalated precursor yog muab tso rau hauv lub kaw qhuav reactor, ib tug tov kua qaub ntxiv, thiab lub reactor yog rhuab mus rau 800-1000 degrees C nyob rau hauv ib tug argon khiav ntawm 80-100 ml / min. Cov tshuaj tiv thaiv lub sij hawm yog 3-8 teev, tom qab ntawd tus nqi txias ib txwm mus txog 20 ° C. Cov txheej txheem rectorite yog tom qab ntawd tshem tawm nrog 30-50% nitric acid los ntawm huab hwm coj kom tawm ntawm graphene thawj cov khoom.
Kauj ruam tsib purify cov khoom. Cov khoom tseem ceeb yog ntxuav nrog alkali tov kom txog thaum lub cawv ntxuav yog nruab nrab thiab ces qhuav. Cov zis yog loj-loj ob-dimensional graphene nrog ib txheej thickness ntawm 2 nm los yog tsawg dua, sib npaug rau ib tug me me ntawm stacked carbon txheej.
| Txheej txheem theem | Qhov tseem ceeb parameter | Kev teeb tsa |
|---|---|---|
| Precursor tsim | CaC2 rau surfactant huab hwm coj piv | 50:(3-6) |
| Precursor tsim | Kub / nplawm | 60-100 ° C / 80-120 rpm / 5-10 min |
| Kev npaj template | Rectorite rau catalyst huab hwm coj piv | 8:(0.1-0.3) |
| Kev npaj template | Microwave ntsuam xyuas / sijhawm | 500-600 W / 3-5 feeb |
| Intercalation | Precursor rau template mass ratio | 1:(3-4) |
| Intercalation | Nqus / dispersion lub sij hawm | 5-10 MPa / 10-20 min ntawm 800-1000 rpm |
| Kev loj hlob tshwm sim | Kub / sijhawm / argon ntws | 800-1000 ° C / 3-8 h / 80-100 ml / min |
| Kev huv huv | Nitric acid zog | 30-50% los ntawm huab hwm coj, ces ntxuav mus rau nruab nrab |
Lub tshuab hluav taws xob xyaum thiab lub zog siv zog ntawm cov Feedstock
Hluav taws xob- txo qhov cub yog tib txoj kev siv rau kev tsim cov calcium carbide. Molten carbide ntws los ntawm lub hauv qab ntawm cov tshuaj tiv thaiv rauv mus rau hauv lub tank txais thiab txias rau hauv cov khoom uas yog tom qab crushed thiab tshuaj ntsuam. Kev ua haujlwm yog siab - kub, plua plav- txheej txheem hnyav. Nyob rau xyoo 1980, tsim ib tonne ntawm cov khoom siv calcium carbide noj 10 mus rau 11 GJ ntawm hluav taws xob hluav taws xob; kaw, loj- lub qhov cub muaj peev xwm tam sim no nyiam dua vim tias lawv txiav cov cua sov thiab ua kom cov pa roj carbon monoxide los ntawm- cov khoom rov qab los ua cov roj los yog cov khoom siv tshuaj lom neeg ntau dua li flaring nws.
Cov Kev Ntsuas Zoo los Qhia rau Cov Khoom Muag Graphene
Peb qhov kev lees paub qhov tseem ceeb tswj tus nqi lag luam ntawm cov khoom tso tawm: txheej thickness, lateral flake size thiab residual inorganic cov ntsiab lus. Ib txheej tuab ntawm 2 nm los yog tsawg dua yuav tsum tau lees paub los ntawm kev tshuaj ntsuam xyuas thiab los ntawm qhov sib thooj ntawm ob- cov ntsiab lus ntawm cov khoom siv, thiab daim ntawv pov thawj tus neeg muag khoom ib leeg tsis muaj pov thawj txaus. Cov residual catalyst thiab av nplaum residues yog tswj los ntawm nitric acid kev kho mob thiab los ntawm kev ntxuav neutralization, yog li acid zog, kev kho mob ntev thiab qhov kawg ntxuav yuav tsum tshwm sim nyob rau hauv cov ntaub ntawv batch. ISO/TS 80004-13 txhais cov graphene thiab cov ntaub ntawv muaj feem xyuam nrog ob sab thiab muab cov lus siv ib txwm siv thaum cov nqi no tau sau rau hauv kev yuav khoom tshwj xeeb.
Ntim, Cia thiab Kev Nyab Xeeb
Calcium carbide yuav tsum tau ceev kom qhuav thiab deb ntawm dej, vim hais tias kev sib cuag nrog noo noo generates acetylene, ib tug flammable gas. Cov nruas hlau kaw nyob rau hauv 50 kg thiab 100 kg qhov ntau thiab tsawg yog cov ntim khoom ib txwm xa tawm, thiab cov pob ntxhib ntawm 50-80 mm yog nyiam rau kev xa tawm vim lawv muaj sia nyob nrog kev nplua tsawg dua. Lub nruas lossis lub hnab uas tau nqus dej yuav tsum tsis txhob qhib rau hauv qhov chaw kaw tsis muaj qhov cua. Nyob rau sab graphene, ziab yuav tsum tau ua kom tiav ua ntej packing: ya raws adsorbed ntawm ib tug siab -surface- cheeb tsam carbon hmoov txhawb re-agglomeration thiab hloov qhov ntsuas particle-loj faib.
Cov lus nug nquag
Q:Dab tsi yog qhov zoo ntawm calcium carbide tshaj graphite li graphene carbon qhov chaw?
A: Cov pa roj carbon monoxide yog twb muaj nyob rau hauv reactive ob - carbon unit, yog li cov txheej txheem zam cov graphite purification thiab hydrocarbon cracking theem uas siv zog ntxiv thiab peev.
Q:Dab tsi loj piv ntawm calcium carbide rau surfactant yog siv nyob rau hauv precursor theem?
A: 50: (3-6), sib tov nyob rau hauv lub kaw agitator ntawm 60-100 degrees C thiab 80-120 rpm rau 5-10 feeb.
Q:Vim li cas lub rectorite ntxuav nrog ethanol ua ntej microwave kauj ruam?
A: Ethanol tshem tawm cov dej adsorbed, thiab cov dej seem seem yuav sib tw nrog cov pa roj carbon precursor thaum nws raug rub mus rau hauv cov chav ua haujlwm interlayer thaum lub tshuab nqus tsev intercalation.
Q:Dab tsi ntawm lub tshuab nqus tsev thiab sib tov ceev yog siv nyob rau hauv dispersing tov khoom?
A: 800-1000 rpm nrog lub tshuab nqus tsev ntawm 5-10 MPa rau 10-20 feeb ntawm qhov ntsuas kub ntawm 60-80 ° C.
Q:Dab tsi yog qhov kev loj hlob hauv cov reactor qhuav?
A: 800-1000 ° C rau 3-8 teev nyob rau hauv argon ntawm 80-100 ml ib feeb, ua raws li ntuj txias txog li 20 ° C.
Q:Yuav ua li cas rectorite template tshem tawm tom qab kev loj hlob?
A: Nrog 30-50% nitric acid los ntawm huab hwm coj, tom qab ntawd cov khoom yog ntxuav nrog alkali tov rau nruab nrab thiab qhuav mus rau qhov kawg graphene hmoov.