Pauna
Say graphite et sakey ya importantin mineral ya aliwan metal ya walay nikadkaduman duaran metal tan aliwan metal ya kablian to. Kabkabat iya bilang "estratehikon rekurso ya onsusuportad iyaaligwas na high-tech ed koma-21 a siglo" tan abayag lan ipapasen ya "black gold". Say high-purity graphite et manutukoy ed graphite ya walay carbon content ya masulok ya 99.99%. Saya so walaan na ekselentin self-lubrication, atagey a biskeg, maong ya electrical conductivity, acid/alkali/corrosion/heat resistance, abeban expansion coefficient, matalonggaring ya chemical stability, atagey ya sealing performance, tan parepareho tan compact ya istruktura. Saya so malaknab ya uusaren ed electrical engineering, metallurgy, depensa na bansa, aerospace, enerhiya, industriya na kemikal tan arum niran sektor. Diad partikular, saya so walaan na desidido tan kritikal a betang ed saray onlelesa ya industriya a singa say panagparaan na komatlon-generasyon na semiconductor materials, industriya na nukleyar, tan industriya na photovoltaic, ya walaan na baleg ya epekto ed ekonomya na China.
1. Saray kablian na graphite ore
Say graphite et sakey a mineral ya tugyopen na carbon elements, say kolor to et maliwliwawan andeket tan walay metal ya kinmiwas tan anisotropy. Say densidad to et 2.09-2.23 g/cm3, melting point 3850 degree, boiling point 4250 degree, heat absorption 6.9036×107 J/kg, ya mangipapanengneng na ekselentin thermal stability.
2. Atagey-Purity Graphite
2.1Natural High-Purity Graphite
Depende ed saray raw materials tan paraan na panagparaan, say high-purity graphite et nayarin naapag ed natural ya high-purity graphite tan synthetic high-purity graphite.
Say natural ya high-purity graphite et malaknab ya uusaren ed nanduruman lawak lapud ekselentin electrical tan thermal conductivity to, singa saray refractory materials, anti-rust coatings, carbon electrodes, generators, lubricants, tan proteksion iran materyales ed industriya na nukleyar. Say sintetikon high-purity graphite, ya parepareho so morpolohiya tan inkaapag-apag na kabaleg na partikulo, et uusaren ed saray prebaked anodes, espisyal a graphite, industriya na nukleyar tan arum niran lawak. Saray paraan na panagparaan na high-purity graphite et manduruma ed nanduruman raw materials.
Anggapoy puron graphite ed kalikasan. Say graphite ore et mabetbet ya walaan na saray dutak a singa say SiO2, Al2O3, FeO, CaO, P2O5, CuO, ya kaslakan ya wala bilang mineral a singa say quartz, pyrite, carbonate, tan saray gaseous components a singa say danum, aspalto, CO2, H2, CH4, tan N4. Kanian, say panagsukimat ed graphite et mankaukolan na determinasyon ya aliwan say fixed carbon content labat no ag pati say volatile matter tan ash content. Say gagala na proseso na panaglinis na graphite et pian epektibon naekal irayan dutak. No mas atagey so puro na graphite (salanti, mas atagey so carbon content to), mas atagey so balor to tan mas malaknab so usaren to.
Say pangiparaan na atagey-purity graphite manlapud natural graphite et kaslakan ya mangilalanor ed manunan panaglinis na graphite ore panamegley na flotation, kaaruman a panaglinis na flotation concentrate panamegley na alkali-acid method odino hydrofluoric acid method, tan diad kaunoran et pakagamor na high-purity graphite products panamegley na atagey- temperatura- odino atagey a temperatura {4} paraan.
2.2 Synthetic High-Purity Graphite
Say sintetikon graphite et kaslakan ya ontutukoy ed saray materyales ya graphite ya ginawa diad pangusar na atagey-kalidad ya petroleum coke tan pitch coke bilang aggregates, ya inyarum so coal tar pitch bilang binder tan arum niran kagawaan, insan na nantutumbokan ya atagey-temperature ya graphitization treatments. Kaslakan, saray raw materials et unona lan natrato insan iiyan ed sakey ya espisyal ya atagey a temperaturan reactor parad graphitization tan purification. Saray manunan klase na hurnoan et kaiba iray Acheson graphitization furnaces, internal series graphitization furnaces, tan continuous graphitization electric furnaces. Say ultra-atagey a temperatura ed hurnoan et mamapa-graphite ed petroleum coke tan pitch coke, tan say halogen gas et ipaloob pian mi-react ed saray impurities, ya insan et na-gasify tan na-volatilize pian nawalaan na atagey-purity ya graphite.
Anggaman nayarin naekal so kabiangan na saray dutak ed petroleum coke tan pitch coke legan na atagey a temperatura na calcination diad panaggawa na sintetikon atagey a puroan a graphite, walaray malinew a kakaukolanen parad asupre tan dapol ed saray hilaw a materyales na petroleum coke. Lapud ondarakel so manguusar na krudon langis ya atagey so asupre to, ondarakel met so atagey ya asupre ya petroleum coke. Pian nasumpal so abeban-sulfur ya pankaukolan na petroleum coke parad sintetikon high-purity ya graphite ya produksyon, dakel ya iskolar so nanggawa na aralem a panagsukimat nipaakar ed makatunongan tan epektibon proseso na desulfurization na petroleum coke.
Say kalinisan na graphite so mandetermina ed performance na serbisyo tan komprehensibon kablian na saray produkton graphite deep-processing. No mas atagey so kalinisan, mas atagey so balor na aplikasyon. Singa bilang:
Say graphite bilang anode material parad lithium-ion ya baterya et mankaukolan na kalinisan ya masulok ya 99.98%;
Say natural ya graphite parad sintetikon artipisyal ya diamante et mankaukolan na kalinisan ya masulok ya 99.999%, ya say boron content to et abeba nen 0.01×10−6;
Say espisyal ya graphite parad aerospace, depensa na bansa, tan industriya na nukleyar et mankaukolan na 99%~99.99% odino mas atagey ni;
Say graphite powder parad panggawa na third-generation semiconductor SiC wafers et mankaukolan na kalinisan ya anggad 99.9995% odino onsulok ni.
Say panaglinis na graphite so pundasyon ed pangiparaan na amin a materyales a graphite tan sakey a kaslakan ya isyu ed panagpaalagey na saray materyales a graphite. Say proseso na panaglinis na graphite ya abeban konsumo na enerhiya, atagey a kapasidad, tan abeban polusyon so pokus na kaplesan ya R&D.
3. Teknolohiya ed Panlinis na Graphite
3.1 Paraan na Pan-float
Diad pangusar ed maong ya floatability na natural ya graphite, saray proseso na flotation ya walaan na multi-stage flows et adesinyo pian ibiig so flake graphite odino microcrystalline graphite manlapud saray mineral ya kaiba to a singa say kaolin, quartz, tan mica ed natural ya graphite ore. Sayan teknolohiya et makapangiter na natural ya graphite ore ya walay grado ton abeba nen 20% pian magmaliw ya graphite concentrate ya walay purity ya 95%, ya maslak ya uusaren bilang raw material parad produksyon na natural ya high-purity graphite.
3.2 Paraan na Alkali-Asido
Say proseso na panaglinis et kaiba so alkali fusion tan acidolysis. Diad alkali fusion, saray impurities ed graphite a singa say Al2O3, Fe2O3, SiO2, MgO, CaO et onreak ed NaOH ed atagey a temperatura pian manporma na water-ag natunaw ya hydroxides; arum ya dutak (alimbawa, SiO2) so mamapawala na saray produkton natunaw ed danum, ya naekal panamegley na panag-leach tan panag-uras na danum. Diad acidolysis, say graphite tan hydroxides kayari na alkali fusion et ilalaok ed hydrochloric acid ya walay pigaran konsentrasyon to parad ambetel ya panag-leach, ya magmaliw iran soluble chlorides ya insan naurasan na danum. Say atagey a -purity ya graphite ya say purity to et masulok ya 99% et nayarin naala kayari na acidolysis.
Diad kaplesan, say alkali-acid a paraan et malaknab ya uusaren ed industriya, ya walaan na saray bentaha a singa say abeban sakey-panaon ya pinansyal, atagey a grado, tan mabiskeg ya pakayarin manguman ed proseso. Balet, wala met iray disbentaha to a singa say atagey a temperatura na calcination, atagey a konsumo na enerhiya, andukey a panaon na reaksion, graben pakaderal na kagawaan, baleg a pakawalaan na graphite, tan graben polusyon ed wastewater.
3.3 Paraan na Panag-ihaw na Chlorination
Diad manga 1000 degree, say chlorine gas et onloob ed graphite. Diad pangusar ed mabiskeg ya oxidizing property na chlorine, saray metal oxide impurities ed graphite et na-oxidize pian magmaliw ya chlorides ya abeba so temperatura na gasification. Diad sayan temperatura, saray metal chloride et maples ya na-gasify tan na-discharge ed baleg a kantidad, ya makagawa na graphite purification.
Say chlorination roasting et kaslakan ya uusaren bilang kaaruman a proseso parad panaglinis na graphite, ya mipara ed arum iran proseso, tan walaan na mapatnag iran bentaha lalo la ed pangekal na saray dutak na metal. Balet, say inka-toxic, inka-corrosive tan polusyon na kaliberliber na chlorine so mamatunda ed inkabantog na sayan proseso anggad sakey a laknab. Niarum ni, mairap so manggawa na ultra-high-purity graphite, tan say ag-establin sistema et mangaapekta met ed praktikal ya aplikasyon to.
3.4 Paraan na Hydrofluoric Acid
Saray dutak ed raw ore et manreak ed hydrofluoric acid pian makagawa na water-soluble fluorides tan fluorosilicates, ya naekal panamegley na water washing pian nawalaan na high-grade graphite.
Saray manunan bentaha na hydrofluoric acid method et atagey ya epektibo ed pangekal na dutak, atagey ya klase na produkto, melag ya epekto ed performance na graphite, tan abeban konsumo na enerhiya. Say disbentaha to et say hydrofluoric acid et makasamal tan makaderal, kanian kaukolan so istrikton proteksion ed produksyon, tan say atagey ya pinansyal ya proteksion ed kaliberliber et mamapaabeba ed kompetisyon to ed ekonomya.
3.5 Paraan na Panlinis ed Atagey a Temperatura
Base ed prinsipyo ya say graphite et atagey so boiling point to bangta arum ya impurities et abeba so boiling point to, say natural ya graphite ya walay carbon content ya manga 80% et iiyan ed purification furnace ya 1500℃pian magmaliw ya gas tan naekal iray abeban -boiling impurities. Insan onloob ed hurnoan diad 25002800℃pian naekal so dakel nin dutak, tan diad kaunoran et sakey a hurnoan ed 28003200℃ya walay matukoy ya HF tan HCl ya gas. Sarayan gas et onkikiwas ed saray atagey a metal ya manpabukal ed atagey a temperatura pian manporma na abeban-manbukal a fluoride tan chloride, ya na-gasify tan na-discharge. Diad onian paraan, say natural ya graphite et nalinisan ya anggad 99.99%~99.9998% ya carbon content.
Saray manunan sengegan ya mangaapekta ed inkapuro na graphite et say kalidad na raw material, kalinisan na graphite crucible, paraan na panagpainit na graphite, tan say kabaleg na partikulo na graphite. Sayan proseso et walaan na atagey iran kakaukolanen parad kalinisan na hilaw a materyales, inkapino na materyales tan teknolohiya na kagawaan, a walaan na atagey a konsumo na enerhiya tan baleg a pinansyal. Kanian, limitado so kaplesan ya aplikasyon to, lalo la ed saray espisyal a lawak a singa say aerospace, depensa na bansa tan industriya na nukleyar ya walaan na atagey a tuloy iran kakaukolanen ed kalidad na graphite.
3.6 Paraan na Panlinis na Halogen Gas
Saray high-in industrial ya aplikasyon (alimbawa, say industriya na semiconductor) et mankaukolan na graphite purity ya onsulok ed 99.999%, ya ag nagawaan diad atagey-temperature ya panaglinis labat. Say industriya et kaslakan ya manguusar na halogen gas purification method (tatawagen met ya physical purification). No ontagey so temperatura na hurnoan tan say grado na vacuum, wala ray dutak ed saray produkton graphite ya automatikon onkupas. Parad arum ya impurities ya mankaukolan na mas atagey a temperatura, saray halogen gases (manunan chlorine tan halogenated hydrocarbons) so manguuman ed saratan pian magmaliw iran halides ya abeba so melting tan boiling points da. Diad silong na pankakasakey ya aksion, naekal iray dutak pian nalinisan so graphite.
4. Pangusar na High-Purity Graphite
4.1 Saray Materyales ya Pan-lubricate
Bilang sakey ed saray kaslakan ya solidon lubricant, say layered structure na graphite so mangiiter ed satan na self-lubricating properties. Diad silong na compressive tan shear stresses legan na dry friction ed saray metal, saray graphite layers et onlelereg, ya manporma na manipis ya graphite transfer film ed metal friction surface diad mikroskopyo. Kanian, say dry friction coefficient ed baetan na graphite tan metal et abeba nen say baetan na saray metal, kanian saya so kaslakan a self-lubricating material.
Saray metal ed metal-graphite friction pairs et kaslakan ya kaiba so 45# steel, 40Cr steel, stainless steel, cast iron, copper alloy, tan arum nira. Say friction tan wear performance na graphite-metal pairs et maapit a misiglaotan ed klase tan kablian na metal iran materyales. Say pambawas na panlalaban tan pan-usar ed baetan na saray paris na panlalaban na makina so manunan paraan pian napaaligwas so inkaepektibo tan bilay na saray mekanikal a kabiangan. Say panaral ed epekto na karga, temperatura, kapeles na panag-slide, itsura tan inkagawa na tapew et ontulong pian napalaknab so bilay na graphite-metal friction pairs.
4.2 Saray Materyales ed Panseal
Say pinalaknab ya graphite et nayarin iproseso ed flexible graphite kayari na post-treatment, ya walay abeban thermal expansion coefficient (1×10−6~30×10−6 K−1). Ag-itan magmaliw ya malimpek o mankibalatar no abeba so temperatura, tan ag-itan onlemek odino onkupas no atagey so temperatura.
No ikompara ed tradisyonal iran materyales ed panag-seal (asbestos, goma, cellulose tan saray composite da), say flexible graphite et walaan na malaknab a temperatura na serbisyo (200~450℃ed dagem). Kanian, say pinalaknab ya graphite et malaknab ya uusaren bilang materyales ed panag-seal ed makinarya, metalurhiya, luluganan, panagpaalagey na barko, petrokemikal tan arum niran lawak.
4.3 Saray Materyales ya Makaamper ed Apoy
Say pinalaknab ya graphite et nayarin i-compound ed saray polymer, resin, tan arum ni pian makagawa na saray materyales ya ag-onkapuy. No walay pool, say nalaknab ya graphite et maples ya onlaknab pian manporma na onlaknab ya thermal insulation layer ed tapew na materyal, ya mangiiter na ekselentin heat insulation tan mangamper ed ipaway na makasamal iran gas.
4.4 Electrode Composite Materials
Say expandable graphite et uusaren ed pangiparaan na nanduruman materyales na electrode na baterya lapud atagey so aktibon tapew to, atagey so chemical stability to, maong so thermal tan electrical conductivity to, tan mainomay ya iparaan. Say malet ya istruktura to et epektibon mamapawala na volume expansion na saray materyales na electrode (alimbawa, diad Li/S o Li/Si ya baterya) legan na panagbisikleta, ya mamaaligwas ed bilay na siklo.
Sakey ni, say mas baleg ya espasyo ed baetan na expandable graphite et mangiiter na mas baleg ya espasyo parad intercalation na Li⁺, Na⁺, Mg2⁺, Zn2⁺ ed metal-ion secondary batteries (lithium-ion, sodium-ion, magnesium-ion, {{}}ion, {{}}ion, adsorcing batteries kapasidad tan karakel na panagtipon na enerhiya. Say expandable graphite et nayarin usaren met bilang materyales na electrode parad saray supercapacitor.
Niarum ni, saray pinalaknab ya graphite composites ya walay polymer matrix to et anlemew, abeba so gastos tan mainomay ya moldien. Saray electrical properties et nayarin i-adjust na malaknab diad panguman ed dosis na expanded graphite.
4.5 Tradisyonal tan Atagey a Panggawa
Saray metalurgical electrodes tan foundry industry so manunan tradisyonal ya panguusaran na graphite, ya manunan uusaren ed panagtunaw na electrodes tan panag-coating parad panag-cast na molde na asero, gansa, aluminum tan arum niran aliwan metal ya ferrous. Say pankaukolan parad graphite ed panaggawa na lapis et mansiansian medyo malet.
Saray materyales ya graphite et walaan na simplin istruktura, anggapoy panmintina, ag-onkupas, atagey so kapasidad dan mangawit na karga tan mabiskeg ya ag-ontutundan ontupak, tan malaknab ya uusaren ed angkakabaleg iran kagawaan ed nuclear power, hydropower, aerospace tan military fields.
4.6 Saray Materyales ed Nuklear ya Power
Say graphite parad nukleyar ya enerhiya et malaknab ya uusaren ed saray reactor ya walay atagey a temperatura na gas, a singa saray conduit, fuel elements tan saray support components. Saray bearing tan guide bearings ed saray advanced nuclear main pumps ed Russia et maslak ya manguusar na siliconized graphite. Say graphite et walaan na ekselentin nuclear performance tan mabetbet ya uusaren bilang moderator tan reflector ed saray reactor.
4.7 Semiconductor Materials
Diad industriya na semiconductor, saray produkton graphite et mabetbet ya uusaren ed saray kagawaan ya atagey so temperatura to a singa say crystal growth furnaces, carbonization furnaces tan graphitization furnaces.
Saray produkton graphite ya atagey so puro to parad komatlon henerasyon na semiconductor silicon carbide (SiC) et kaiba iray graphite crucibles, heaters tan pulbos parad idakel na kristal, ya say puro to et mandetermina ed kalidad na SiC crystals. Say panaglinis ed ontan ya atagey a -purity graphite et kaslakan ya manguusar na pisikal-kemikal iran paraan, ya mankaukolan na puro ya Mas atagey o mipara ed 99.9995%, ya walay istrikton limitasyon ed saray indibidual ya karutakan (alimbawa, B Mas abeba odino mipara ed 0.05×10⁻⁶, Al Mas abeba odino mipara ed 0.05×10−6).
4.8 Sintetikon Diamante iran Materyales
Diad kaplesan, say single-crystal diamond et manunan gagawaen panamegley na High-Pressure High-Temperature (HPHT) ya paraan tan Chemical Vapor Deposition (CVD) ya paraan. Say CVD et manguusar na hydrogen- ya gas ya walay laman to (methane, hydrogen, tan arum ni), ya pansengegan na hydrogen impurities tan stress ed saray kristal na diamante. Say HPHT diamond ya walay tradisyonal ya alloys bilang catalyst et walaan na pigaran metal ya dutak, kanian mairap tan makapaangat so panaggawa na "ultra-pure" ya diamond.
Recent breakthroughs in static ultra-high pressure technology have enabled direct synthesis of diamond from graphite under extreme P-T conditions (>15 GPa, 2000℃). Diad ontan iran kondisyon, say graphite et maples ya magmaliw ya diamante, ya mamawala na centimeter- ya kabaleg na polycrystalline aggregates ya atagey so puro to.
Konklusyon
Saray manunan klase na graphite ya uusaren ed China et kaiba so high-purity graphite, isostatic pressing graphite, expandable graphite, fluorinated graphite, colloidal graphite tan graphene. Say pamaaligwas ed kalinisan na graphite et sakey a kaslakan a kakaukolanen ed amin a produkto na graphite-manunan balet ta makapaangat.
Lapud say pankaukolan parad high-purity graphite ed saray high-tech fields et tuloytuloy ya ombabaleg tan saray kakaukolanen ed purity et lalon onkakasil, saray misiglaotan a teknolohiya so walad kritikal a yugtan ya manaalagar na saray pananguman.
