Alumina

Aluminum oxide faruwa a wannan yanayi a cikin nau'i na al'ada alumina, ta sinadaran dabara - AL2O3. A wannan irin lu'ulu'u da aka ba da ciwon launuka da suke a zazzabi na 2044 ° C fara ya narke, da kuma lokacin da matakin na 3530 ° C tafasa.

A halitta kewaye kawai barga gyara abu ne aluminum oxide da ciwon yawa daga 3,99 g / cm3. Wannan ne mai matukar m samfurin na zuwa na tara matakin na Mohs tebur. Tamanin da Refractive index ne kamar haka: ga talakawa ray - 1.765 da kuma 1.759 ga m. A halitta kewaye alumina sau da yawa ya ƙunshi daban-daban karfe oxides, duk da haka, ma'adinai corundum iya saya daban-daban inuwõyinta suna kusa da launi. Alal misali, sũ ne waɗanda sapphires, yaƙũtu da sauran duwatsu masu daraja. Kamar yadda irin wannan, da alumina iya shirya da kuma awon-sinadaran Hanyar. A saboda wannan dalili, A12O3 metastable tsari da kuma su bazu thermally. Har ila yau, a matsayin tushen da dakin gwaje-gwaje Hanyar amfani da aluminum oxide , aluminum hydroxide.

Standard gyara fili ne tetragonicheskuyu raga dauke a cikin abun da ke ciki game da 1-2% ruwa. Za a iya samu amorphous a tsarin alumina - alumina gel, wanda gelevidny bayani daga AL (OH) 3 da aka dewatered su sami wani porous abu m taro.

Aluminum oxide ne gaba daya insoluble a ruwa amma za a iya da kyau narkar da a cryolite, mai tsanani zuwa high zazzabi. Amphoteric abu. Characteristically irin wannan dukiya na hada alumina a matsayin kishiya dogara da da samuwar zafin jiki da kuma sinadaran aiki. Kamar yadda wucin gadi (Ina nufin, samu a zazzabi na kan 1200 ° C) da na halitta corundum a wani talakawa yanayi nuna kusan xari bisa dari cikakken sinadaran inertness da kuma rashin hygroscopicity.

Oxide aluminum sinadaran Properties fara rayayye motsa jiki a yanayin zafi a kusa da 1000 ° C, a lõkacin da ta fara hanzari hulɗa tare da abubuwa irin su daban-daban Alkali carbonates Alkali karafa. Lokacin da wannan hulda aluminates suna kafa. A hankali fili reacts tare da SiO2, kazalika da iri daban-daban acidic slags. A sakamakon wadannan interactions da samu aluminosilicates.

Alumina gel da kuma alumina wanda aka shirya da calcination na aluminum hydroxides a kowane akalla 550 ° C, da sosai high hygroscopicity, m shiga cikin sinadaran halayen da kuma rayayye hulɗa tare da acidic da alkaline mafita.

Yawanci, a matsayin albarkatun kasa domin samar da aluminum oxide ana amfani da haƙar alunite da nepheline. Lokacin da abun ciki na dũkiyõyinsu a tambaya a gare su fiye da 6-7% samar ne babban hanya - by Bayer, kuma a wani m abun ciki na abu amfani tama sintering Hanyar da lemun tsami ko soda. Bayer tsari ne mai aiki murƙushe dutse a ball Mills, bi haƙar aka bi da tare da alkaline mafita a zazzabi na 225-250 ° C. A abun da ke ciki kamar haka samu aka diluted da ruwa-ruwa sodium aluminate bayani da kuma tace. A kan aiwatar da tace a slurry dauke da alumina, wanda Properties dace ga misali, an bazu a centrifuges. Irin wannan fasahar damar zuwa samu 50% yawan amfanin ƙasa na abu. Bugu da ƙari kuma, da yin amfani da wannan hanya ya sa ya yiwu a ci gaba da uwar sayar da giya don amfani a m ayyukan da leaching na haƙar.

Kullum, da sakamakon roba Hanyar aluminum oxide da ake amfani da matsayin tsaka-tsaki abu da shiri na m aluminum. A masana'antu, shi da ake amfani da matsayin albarkatun kasa domin samar da tsaurin kayan, yumbu abrasive da kuma yankan kayan aikin. Modern fasahar rayayye tambaya guda lu'ulu'u na aluminum oxide a samar hours, PCB, kayan ado.