Aluminum oxide
Nā waiwai: paʻa keʻokeʻo ʻaʻole hiki ke hoʻoheheʻe ʻia i ka wai, ʻaʻala ʻole, ʻono ʻole, paʻakikī loa, maʻalahi ke komo i ka makū me ka ʻole o ka delixing (ke ahi wela).ʻO ka alumina kahi amphoteric oxide maʻamau (ʻo ka corundum he ʻano α-a no ka paʻi hexagonal ʻoi loa, he pūhui inert, hiki ke hoʻoheheʻe iki ʻia i ka waika a me ke kūpaʻa ʻino alkali [1]), hiki ke hoʻoheheʻe ʻia i loko o ka waika inorganic a me nā hopena alkaline, aneane hiki ʻole ke hoʻoheheʻe ʻia i ka wai. a me nā mea hoʻoheheʻe organik non-polar;Māmā pili (d204) 4.0;Ka helu hehee: 2050 ℃.
Waiho: E hoʻopaʻa paʻa a maloʻo.
Hoʻohana: Hoʻohana ʻia e like me ka analytical reagent, organic solvent dehydration, adsorbent, organic reaction catalyst, abrasive, polishing agent, nā mea maka no ka hoʻoheheʻe ʻana i ka alumini, refractory.
Nā mea nui
Aia ka alumina i nā mea alumini a me ka oxygen.Inā ʻo ka bauxite ma o ka hoʻomaʻamaʻa kemika, e hoʻoneʻe i nā oxides o ke silika, ka hao, ka titanium a me nā huahana ʻē aʻe he alumina maʻemaʻe loa, ʻoi aku ka nui o Al2O3 ma mua o 99%.ʻO ka māhele mineral he 40% ~ 76% γ-Al2O3 a me 24% ~ 60% α-Al2O3.Hoʻololi ʻo γ-Al2O3 i α-Al2O3 ma 950 ~ 1200 ℃, me ka emi ʻana o ka nui.
ʻO ka alumini oxide (aluminium oxide) he ʻano inorganic, ʻano kemika Al2O3, he ʻano o nā pūhui paʻakikī kiʻekiʻe, kahi heheʻe o 2054 ℃, kahi paila o 2980 ℃, kristal ionized i ke kiʻekiʻe wela, hoʻohana pinepine ʻia i ka hana ʻana i nā mea refractory. .
Hoʻomākaukau ʻia ka alumina ʻoihana e ka bauxite (Al2O3 · 3H2O) a me ka diaspore.No ka Al2O3 me ke koi maʻemaʻe kiʻekiʻe, hoʻomākaukau ʻia ia e ke ʻano kemika.He nui nā heterocrystals homogenous o Al2O3, aia ma mua o 10 i ʻike ʻia, aia ka nui o nā ʻano kristal 3, ʻo ia hoʻi α-Al2O3, β-Al2O3, γ-Al2O3.Ma waena o lākou, ʻokoʻa ke ʻano a me nā waiwai, a ʻo ka α-Al2O3 ua aneane e hoʻololi ʻia i α-al2o3 ma ke kiʻekiʻe wela ma luna o 1300 ℃.
Nā waiwai kino
InChI = 1 / Al 2 o/rAlO ₂ / c2-1-3
Kaumaha molekula: 101.96
Ka helu hehee: 2054 ℃
Puni paila: 2980 ℃
ʻAiʻi maoli: 3.97g /cm3
Mānoanoa paʻa paʻa haʻahaʻa: 0.85 g/mL (325 mesh ~0) 0.9 g/mL (120 mesh ~325 mesh)
ʻO ka hana aniani: ʻōnaehana tripartite hex
Solubility: hiki ʻole ke hoʻoheheʻe ʻia i loko o ka wai ma ka lumi wela
Ka hoʻoili uila: ʻAʻohe hoʻoili uila ma ka wela lumi
ʻO Al₂O₃ he aniani ionic
Hoʻohana ʻāpana alumina ---- corundum hana
Hiki ke hoʻohana ʻia ka paʻakikī o Corundum e like me ka abrasive, polishing pauka, kiʻekiʻe kiʻekiʻe kiʻekiʻe kiʻekiʻe sintered alumina, i kapa ʻia ʻo corundum artificial a i ʻole pōhaku pōhaku artificial, hiki ke hana ʻia i nā bearings mechanical a i ʻole nā wati i ke daimana.Hoʻohana ʻia ʻo Alumina e like me ke kiʻekiʻe wela refractory mea, hana i nā pōhaku lepo refractory, crucible, porcelain, artificial gems, alumina nō hoʻi ka mea maka o ka hoʻoheheʻe alumini.Hiki ke hana i ka γ-.Hiki ke hoʻohana ʻia ʻo Gamma-al ₂O₃ (ma muli o kāna adsorption ikaika a me ka hana catalytic) ma ke ʻano he adsorbent a me ka catalyst.ʻO ka mea nui o ka corundum, alpha-al ₂O₃.ʻO ke aniani ʻekolu ma ke ʻano o ka barela a i ʻole cone.Loaʻa iā ia ka luster aniani a i ʻole ke daimana.ʻO 3.9 ~ 4.1g/cm3 ka mānoanoa, ʻo 9 ka paʻakikī, ʻo ka helu hoʻoheheʻe he 2000 ± 15 ℃.ʻAʻole hiki ke hoʻoheheʻe ʻia i ka wai, a ʻaʻole hiki ke hoʻoheheʻe ʻia i loko o nā waikawa a me nā kumu.Kūleʻa wela kiʻekiʻe.Ua ʻōlelo ʻia he jade keʻokeʻo keʻokeʻo ʻaʻohe waihoʻoluʻu, aia i loko o ka ʻulaʻula trivalent chromium i kapa ʻia ʻo ruby;ʻO ke kala uliuli i loko o ʻelua -, ʻekolu - a i ʻole ʻehā - valent iron ua kapa ʻia ʻo sapphire;Loaʻa ka liʻiliʻi o ka ferric oxide ʻeleʻele hina, ʻeleʻele i kapa ʻia ka pauda corundum.Hiki ke hoʻohana ʻia e like me nā bearings no nā mea kani pololei, nā daimana no nā uaki, nā huila wili, nā polishes, refractories a me nā insulators uila.Hoʻohana ʻia nā pōhaku makamae ʻulaʻula no ka hoʻonaninani.ʻO ka ruby synthetic hoʻokahi mea laser kristal.Ma waho aʻe o nā minela kūlohelohe, hiki ke hana ʻia e ka hydrogen a me ka oxygen flame melting aluminum hydroxide.
Alumina keramika
Hoʻokaʻawale ʻia ka alumina i ka alumina calcined a me ka alumina ʻoihana maʻamau.ʻO ka alumina calcined kahi mea waiwai nui no ka hana ʻana i nā pōhaku kahiko, ʻoiai hiki ke hoʻohana ʻia ka alumina ʻoihana no ka hana ʻana i nā pōhaku microcrystalline.I nā glazes kahiko, hoʻohana pinepine ʻia ka alumina e like me ke keʻokeʻo.Ke hoʻonui nei ka hoʻohana ʻana i ka alumina i kēlā me kēia makahiki e like me nā pōhaku kahiko a me nā pōhaku microcrystalline i makemake ʻia e ka mākeke.
No laila, ua puka mai ka alumina seramika i loko o ka ʻoihana seramika -- ʻo ka alumina seramika kekahi ʻano mea seramika me Al₂O₃ ma ke ʻano kumu kumu a me ka corundum ma ke ʻano o ka crystalline phase.Ma muli o kona ikaika mechanical kiʻekiʻe, kiʻekiʻe paʻakikī, kiʻekiʻe frequency dielectric nalowale, kiʻekiʻe wela insulation kū'ē, kemika corrosion kū'ē a me ka maikaʻi thermal conductivity a me nā pono 'ē aʻe o ka maikaʻi hoʻokō loea.
