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Uyini umehluko phakathi kwe-alumina, i-corundum nesafire?

Uyini umehluko phakathi kwe-alumina, i-corundum nesafire?

Kunezinhlobo eziningi ze-alumina. Lapho abangani abaningi bezwa amabizo anjengokuthi “alumina”, “corundum”, “ruby” kanye “nesafire”, abakwazi ukuhlukanisa umehluko phakathi kwalokhu futhi ngokuvamile bazizwa bedidekile. Yiqiniso, lesi simo sihlobene nokushoda kwamanje kwamazinga afanayo ezinhlobonhlobo eziningi ze-alumina. Ukuze uwahlukanise, umbhali uzohlanganisa ulwazi oluthile ukuze akusize uhlonze le migomo.

1. I-Alumina

I-Alumina, evame ukubizwa ngokuthi i-bauxite, inokuminyana okungu-3.9-4.0g/cm3, indawo yokuncibilika engu-2050°C, indawo yokubilisa engu-2980°C, futhi ayincibiliki emanzini. I-Alumina ingakhishwa ku-bauxite embonini. . Phakathi kwalokhu okuhlukile kwe-Al2O3, i-α-Al2O3 kuphela ezinzile, futhi amanye amafomu ekristalu azinzile. Njengoba izinga lokushisa likhuphuka, lawa mafomu ekristalu eshintshayo azogcina eguqule abe yi-α-Al2O3.

Ku-crystal lattice ye-α-alumina, ama-ion omoya-mpilo apakishwe eduze kuma-hexagon, futhi i-Al3+ isatshalaliswa ngokulinganayo phakathi nendawo ye-octahedral ligand ezungezwe ama-ion komoyampilo. Amandla e-lattice makhulu kakhulu, ngakho-ke indawo yokuncibilika kanye nendawo yokubilisa kuphezulu kakhulu. I-Alpha-alumina ayincibiliki emanzini nase-asidi. Yaziwa nangokuthi i-aluminium oxide embonini futhi iyimpahla eyisisekelo yokulungisa i-aluminium yensimbi. Ngaphezu kwalokho, ingase isetshenziselwe ukulungisa izinto ezihlukahlukene zokuphikisa, izinto ezi-abrasive, nama-substrates amasekhethi ahlanganisiwe. Ngaphezu kwalokho, ukuhlanzeka okuphezulu kwe-α-alumina nakho kuyimpahla eluhlaza yokukhiqiza i-corundum yokufakelwa, amarubi okwenziwa namasafire.

I-alumina yohlobo lwe-γ ikhiqizwa ukuphelelwa amanzi kwe-aluminium hydroxide ezingeni lokushisa elingu-500-600 ° C, futhi ibizwa nangokuthi i-alumina ecushiwe embonini. Ngokwesakhiwo sayo, ama-ion omoya-mpilo acishe aminyene ezindizeni eziqondile, futhi i-Al3+ isakazwa ngokungavamile ku-octahedral kanye ne-tetrahedral voids ezungezwe ama-ion oksijini. Ingasetshenziswa njengama-catalysts, abathwali be-catalyst, ama-adsorbents, ama-desiccants, njll embonini. Labo abanentshisekelo kule sampuli bangaphequlula okuthunyelwe kokuthi “Ukulungiselela Nokusetshenziswa Kwe-Alumina Ecushiwe”.

Ngamafuphi: I-Alumina ingabhekwa njengento eyakhiwe i-Al2O3 (iqukethe ukungcola okuthile, ngokuvamile okungahlanzekile). Lolu hlobo lwento lunezinhlaka ezihlukene zekristalu, ubumsulwa bomkhiqizo obuhlukene, kanye namafomu ahlukene, amele imikhiqizo ehlukene. , Isetshenziswa emikhakheni ehlukene.

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Ibhola le-alumina ephezulu-ingxenye eyinhloko i-alumina

2. I-Corundum ne-artificial corundum

Amakristalu e-alumina ohlobo lwe-α avele ngokwemvelo abizwa ngokuthi i-corundum, futhi ngokuvamile abonisa imibala ehlukene ngenxa yokungcola okuhlukile. I-Corundum ngokuvamile inombala oluhlaza okwesibhakabhaka noma ophuzi ngokumpunga, inengilazi noma idayimane elikhazimulayo, ukuminyana okungu-3.9-4.1g/cm3, ubulukhuni obungu-8.8, okwesibili ngemva kwedayimane ne-silicon carbide, futhi ingakwazi ukumelana namazinga okushisa aphezulu.

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I-corundum ephuzi yemvelo

Kukhona ikakhulukazi izinhlobo ezintathu ze-corundum yemvelo emvelweni: a. I-corundum yekhwalithi ephezulu, eyaziwa ngokuthi i-gemstone: isafire iqukethe i-titanium, i-ruby ​​iqukethe i-chromium, njll; b corundum evamile: obomvu omnyama noma onsundu; c emery: ingahlukaniswa nge-emerald emery kanye ne-limonite emery, Iwuhlobo lwe-crystal aggregate enobulukhuni obuphansi. Phakathi kwalezi zinhlobo ezintathu ezingenhla ze-corundum yemvelo, eyokuqala isetshenziselwa ikakhulukazi ubucwebe, kanti lezi ezimbili zokugcina zingasetshenziswa njengama-abrasives ukwenza amasondo okugaya, ama-oilstones, i-sandpaper, indwangu ye-emery noma impushana, ama-abrasive paste, njll.

Ngenxa yokuthi ukukhishwa kwe-corundum yemvelo kuyashoda, i-corundum esetshenziswa embonini iningi le-corundum yokwenziwa esikhundleni semikhiqizo ye-corundum yemvelo.

I-Alumina ye-Industrial iyimpushana ye-crystalline evulekile enesakhiwo esinezimbotshana futhi esixekethile, esingahambisani nokuthintana kwamakristalu e-Al2O3 nomunye nomunye futhi ngaleyo ndlela ayihambisani ne-sintering. Ngokuvamile ngemva kokubala noma ukuhlanganiswa kabusha kwekristalu, i-γ-Al2O3 iba i-α-Al2O3 (corundum) yokucwilisa nokuhlanganisa. Ngokwendlela yokukhiqiza, i-corundum ihlukaniswe yaba ukukhanya okushisiwe (1350 ~ 1550 ℃) i-corundum (eyaziwa nangokuthi i-light burned α-Al2O3), i-sintered (1750 ~ 1950℃) corundum, ne-fused corundum.

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Isihlabathi se-corundum-white corundum yokwenziwa

Ngamafuphi: kuwumkhuba ukubiza i-α-crystal alumina njenge-corundum. Kungakhathaliseki ukuthi i-corundum yemvelo noma i-corundum yokufakelwa, into eyinhloko eyinhloko ye-corundum i-alumina, futhi isigaba sayo esiyinhloko se-crystal i-α-alumina.

3. I-Gem grade corundum kanye nerubi yokwenziwa, isafire

I-corundum yekhwalithi ephezulu exutshwe nenani elincane lokungcola okuhlukile kwe-oxide iyirubi edumile nesafire, okuwumsebenzi wokwenza ubucwebe obuyigugu, futhi izinhlayiya zayo zingasetshenziswa ukwenza ama-bearings wamathuluzi anembile namawashi.

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lesafire

Njengamanje, ukuhlanganiswa kwesafire ebomvu kuhlanganisa indlela yokuncibilika komlilo (indlela yokuncibilikisa umlilo), indlela ye-flux, indlela ye-hydrothermal nokunye. Phakathi kwazo, izimo zobuchwepheshe zendlela ye-hydrothermal ziphakeme futhi zinzima, futhi ubunzima bukhulu, kodwa

Njengamanje, ukuhlanganiswa kwesafire ebomvu kuhlanganisa indlela yokuncibilika komlilo (indlela yokuncibilikisa umlilo), indlela ye-flux, indlela ye-hydrothermal nokunye. Phakathi kwazo, indlela ye-hydrothermal inezimo eziphezulu zobuchwepheshe kanye nezimo ezinzima zobuchwepheshe. Kodwa-ke, ukukhula kwamakristalu ayigugu kufana kakhulu namakristalu ayigugu emvelo. Kungaba inkohliso kakhulu, futhi iqiniso kanye mbumbulu awahlukaniseki. Amakristalu ayigugu akhule ngale ndlela ahlanganisa ama-emerald, amakristalu, amarubi, njll.

Okubomvu okufakelwayo kanye nesafire akufani nje nemikhiqizo yemvelo ngokubukeka, kodwa futhi nasezindaweni ezingokwenyama namakhemikhali kanye ne-optical, kodwa intengo yi-1/3 kuphela ku-1/20 yemikhiqizo yemvelo. Ngaphansi kwesibonakhulu kuphela lapho kungatholakala khona umoya omncane kumagugu okwenziwa Amabhamuza ayindilinga, futhi amabhamuza omoya emikhiqizweni yemvelo ayisicaba.

Ngamafuphi: nakuba i-alumina, i-corundum, i-ruby nesafire inamagama ahlukene, ukubunjwa kwawo, ubunzima, izakhiwo, kanye nokusetshenziswa nakho kuhlukile, kodwa i-chemistry yabo eyinhloko i-alumina. Ifomu lekristalu eliyinhloko le-corundum i-α-type alumina. I-Corundum i-polycrystalline α-alumina material, futhi i-corundum yekhwalithi ephezulu (i-jewel-grade corundum) iwumkhiqizo owodwa wekristalu we-alumina.

Ngenxa yokulinganiselwa kolwazi lombhali, i-athikili ichaza kabanzi ngezinkulumo ezingafanele. Ngicela izeluleko nakochwepheshe bemboni, ngiyabonga.