Cov txheej txheem ntawm "graphitization" txhais li cas tiag?

"Kev kos duab"

"Graphitization" yog hais txog cov txheej txheem kho cua sov siab (feem ntau ua ntawm 2000 ° C txog 3000 ° C lossis siab dua) uas hloov cov qauv me me ntawm cov khoom siv carbonaceous (xws li petroleum coke, thee tar pitch, anthracite thee, thiab lwm yam) los ntawm lub xeev tsis sib xws lossis qis-txiav txim siab mus rau hauv cov qauv crystalline txheej zoo ib yam li graphite ntuj. Lub hauv paus ntawm cov txheej txheem no yog nyob rau hauv kev hloov pauv tseem ceeb ntawm cov pa roj carbon atoms, uas muab cov khoom siv nrog cov khoom siv lub cev thiab tshuaj lom neeg tshwj xeeb ntawm graphite.

Cov Txheej Txheem Nthuav Dav thiab Cov Txheej Txheem ntawm Graphitization

Cov Theem Kho Mob Kub

1. Thaj Chaw Kub Qis (<1000°C)
   • Cov khoom uas yaj tau (piv txwv li, cov dej noo, cov hydrocarbons me me) maj mam yaj, thiab cov qauv pib ntswj me ntsis. Txawm li cas los xij, cov pa roj carbon feem ntau tseem tsis sib haum xeeb lossis luv luv.
2. Thaj Chaw Kub Nruab Nrab (1000–2000°C)
   • Cov pa roj carbon pib hloov pauv los ntawm kev txav mus los ntawm cua sov, tsim cov qauv sib txuas hexagonal uas tau teeb tsa hauv zos (zoo li cov qauv hauv-dav hlau ntawm graphite). Txawm li cas los xij, kev sib dhos ntawm cov txheej tseem tsis sib xws.
3. Thaj Chaw Kub Siab (>2000°C)
   • Nyob rau hauv qhov kub siab ntev, cov txheej carbon maj mam sib dhos ua ke, tsim cov qauv crystalline peb-seem (graphitized structure). Cov zog interlayer tsis muaj zog (van der Waals kev sib cuam tshuam), thaum lub zog covalent bond hauv-dav hlau nce ntxiv.

Cov Kev Hloov Pauv Tseem Ceeb ntawm Cov Qauv

• Kev Hloov Kho Dua Tshiab ntawm Cov Pa roj carbon: Hloov pauv ntawm cov qauv amorphous "turbostatic" mus rau cov qauv "txheej txheem", nrog rau cov pa roj carbon hauv-dav hlau tsim cov sp² hybridized covalent bonds thiab interlayer bonding ntawm van der Waals forces.
• Kev Tshem Tawm Qhov Tsis Zoo: Qhov kub siab txo cov qhov tsis zoo ntawm cov pob zeb crystalline (piv txwv li, qhov tsis muaj dab tsi, qhov tawg), txhim kho qhov crystallinity thiab kev ruaj khov ntawm cov qauv.

Lub Hom Phiaj Tseem Ceeb ntawm Graphitization

1. Kev Ua Hluav Taws Xob Zoo Dua
   • Cov pa roj carbon uas tau txiav txim siab tsim ib lub network conductive, ua rau muaj kev txav mus los ntawm cov electron dawb hauv cov khaubncaws sab nraud povtseg thiab txo qhov resistivity (piv txwv li, graphitized petroleum coke qhia txog qhov resistivity ntau dua 10 npaug qis dua li cov ntaub ntawv tsis yog graphitized).
   • Daim Ntawv Thov: Cov electrodes roj teeb, cov txhuam carbon, cov khoom siv hluav taws xob uas xav tau kev conductivity siab.
2. Kev Ruaj Ntseg Thermal Zoo Dua
   • Cov qauv txiav txim siab tiv taus oxidation lossis decomposition ntawm qhov kub siab, ua kom muaj kev tiv taus cua sov (piv txwv li, cov ntaub ntawv graphitized tiv taus >3000 ° C hauv inert atmospheres).
   • Daim Ntawv Thov: Cov ntaub ntawv refractory, cov crucibles kub siab, cov tshuab tiv thaiv thermal spacecraft.
3. Cov Khoom Siv Kho Tshuab Zoo Tshaj Plaws
   • Txawm hais tias graphitization yuav txo qhov muaj zog tag nrho (piv txwv li, lub zog compressive poob qis), cov qauv txheej txheem ua rau muaj anisotropy, tswj hwm lub zog siab hauv-dav hlau thiab txo qhov brittleness.
   • Daim Ntawv Thov: Graphite electrodes, cov cathode blocks loj uas xav tau kev tiv thaiv thermal shock thiab kev hnav tsis kam.
4. Kev Ruaj Ntseg Tshuaj Ntau Ntxiv
   • Kev siv lead ua siab txo cov chaw ua haujlwm ntawm qhov chaw, txo cov kev cuam tshuam nrog cov pa oxygen, cov kua qaub, lossis cov hauv paus, thiab txhim kho kev tiv thaiv corrosion.
   • Daim Ntawv Thov: Cov thawv tshuaj, cov ntaub electrolyzer hauv cov chaw corrosive.

Cov Yam Uas Cuam Tshuam Rau Kev Ua Graphitization

1. Cov Khoom Siv Raw
   • Cov pa roj carbon ntau dua ua rau muaj graphitization (piv txwv li, roj av coke graphitizes yooj yim dua li cov thee tar pitch).
   • Cov khoom tsis huv (piv txwv li, sulfur, nitrogen) cuam tshuam rau kev hloov pauv atomic thiab xav tau kev kho ua ntej (piv txwv li, desulfurization).
2. Cov Kev Kho Mob Kub
   • Kub: Kub dua ua rau qib graphitization nce ntxiv tab sis ua rau cov nqi khoom siv thiab kev siv zog ntau ntxiv.
   • Lub Sijhawm: Lub sijhawm tuav ntev dua yuav ua rau cov qauv zoo nkauj dua, tab sis lub sijhawm ntev dhau yuav ua rau cov noob nplej ntxhib thiab ua rau kev ua haujlwm poob qis.
   • Huab Cua: Cov chaw tsis muaj zog (piv txwv li, argon) lossis cov tshuab nqus tsev tiv thaiv kev oxidation thiab txhawb kev ua kom muaj graphitization.
3. Cov khoom ntxiv
   • Cov tshuaj catalysts (piv txwv li, boron, silicon) txo qhov kub ntawm graphitization thiab txhim kho kev ua haujlwm (piv txwv li, boron doping txo qhov kub uas xav tau los ntawm ~ 500 ° C).

Kev Sib Piv ntawm Cov Khoom Siv Graphitized vs. Cov Khoom Siv Tsis-Graphitized

Cov Ntaub Ntawv Siv Tau

1. Cov Khoom Siv Hluav Taws Xob Graphite
   • Petroleum coke los yog thee tar pitch yog graphitized los tsim cov high-conductivity, high-strength electrodes rau hluav taws xob arc cub tawg steelmaking, enduring >3000 ° C thiab muaj zog currents.
2. Cov Anodes ntawm Lithium-Ion Battery
   • Cov graphite ntuj lossis cov khoom siv hluavtaws (graphitized) ua haujlwm ua cov khoom siv anode, siv nws cov qauv txheej txheem rau kev sib xyaw ua ke / deintercalation sai ntawm lithium-ion, txhim kho kev ua haujlwm ntawm kev them / tso tawm.
3. Cov Khoom Siv Carburizer Rau Kev Ua Hlau
   • Cov roj av graphitized, nrog nws cov qauv porous thiab cov ntsiab lus carbon siab, ua rau cov ntsiab lus carbon sai sai hauv cov hlau molten thaum txo qis kev nkag mus ntawm sulfur impurity.