I-Alumina itholwe inezinhlobo eziyi-8 okungenani, ziyi-α- Al2O3, θ-Al2O3, γ- Al2O3, δ- Al2O3, η- Al2O3, χ- Al2O3, κ- Al2O3 kanye ne-ρ- Al2O3, izakhiwo zazo ze-macroscopic ngokulandelana kwazo. nazo zihlukile.I-alumina ecushiwe ye-Gamma iyikristalu evaliwe evaliwe, engancibiliki emanzini, kodwa encibilika ku-asidi ne-alkali.I-alumina ecushiwe ye-Gamma isekela i-asidi ebuthakathaka, inephuzu lokuncibilika eliphakeme elingu-2050 ℃, ijeli ye-alumina esesimweni se-hydrate ingenziwa ibe yi-oxide ene-porosity ephezulu kanye nendawo ethile ephezulu, inezigaba zoshintsho ebangeni elibanzi lokushisa.Emazingeni okushisa aphezulu, ngenxa yokuphelelwa amanzi emzimbeni kanye ne-dehydroxylation, i-Al2O3surface ibonakala ixhumanisa umoya-mpilo ongagcwele (isikhungo se-alkali) ne-aluminium (isikhungo se-asidi), nomsebenzi we-catalytic.Ngakho-ke, i-alumina ingasetshenziswa njengesithwali, i-catalyst kanye ne-cocatalyst.
I-alumina ecushiwe ye-Gamma ingaba impushana, ama-granules, imichilo noma okunye.Singenza njengemfuneko yakho.γ-Al2O3, yayibizwa ngokuthi “i-alumina ecushiwe”, iwuhlobo lwezinto eziqinile ezihlakazekayo ezinezimbobo, ngenxa yesakhiwo sayo sezimbotshana ezilungisekayo, indawo enkulu ethile engaphezulu, ukusebenza kahle kwe-adsorption, indawo engaphezulu enezinzuzo ze-asidi. kanye nokuzinza okuhle kokushisa, indawo engaphansi kwe-microporous enezici ezidingekayo zesenzo se-catalytic, ngakho-ke iba yi-catalyst esetshenziswa kakhulu, i-catalyst carrier kanye ne-chromatography carrier embonini yamakhemikhali namafutha, futhi idlala indima ebalulekile ku-oyela hydrocracking, i-hydrogenation refining, i-hydrogenation reforming, ukusabela kwe-dehydrogenation kanye nenqubo yokuhlanza i-exhaust yemoto.I-Gamma-Al2O3 isetshenziswa kabanzi njengesithwali se-catalyst ngenxa yokulungiseka kwesakhiwo sayo sezimbotshana kanye ne-asidi engaphezulu.Uma i-γ- Al2O3 isetshenziswa njengesiphathi, ngaphandle kwalokho ingaba nemiphumela yokuhlakaza nokuzinzisa izingxenye ezisebenzayo, futhi inganikeza isikhungo esisebenzayo se-asidi ye-alkali, ukusabela kwe-synergistic nezingxenye ezisebenzayo ze-catalytic.Isakhiwo sezimbotshana nezindawo ezingaphezulu ze-catalyst zincike kusithwali se-γ-Al2O3, ngakho-ke inkampani yenethiwekhi yokusebenza ephezulu ingatholwa ukuze kutholakale ukusabela okuthile kwe-catalytic ngokulawula izakhiwo ze-gamma alumina carrier.
I-alumina ecushiwe ye-Gamma ngokuvamile yenziwa ngelenduleli yayo i-pseudo-boehmite ngokusebenzisa izinga lokushisa eliphakeme elingu-400 ~ 600℃, ngakho izici ze-physicochemical ezingaphezulu zinqunywa umanduleli wayo mbumbulu, kodwa ziningi izindlela zokwenza i-pseudo-boehmite, kanye nemithombo ehlukene. ye-pseudo-boehmite iholela ezinhlobonhlobo ze-gamma - Al2O3.Nokho, kulawo ama-catalyst anezidingo ezikhethekile ku-alumina carrier, ukuthembela kuphela ekulawuleni i-precursor pseudo-boehmite okunzima ukuyifinyelela, kufanele kuthathwe ukuze kusetshenziswe i-prophase yokulungiselela nokucubungula ukuhlanganisa izindlela zokuhlanganisa ukulungisa izakhiwo ze-alumina ukuze zihlangabezane nezidingo ezahlukene.Lapho izinga lokushisa lingaphezu kuka-1000 ℃ elisetshenziswayo, i-alumina iyenzeka ngokulandelayo ukuguqulwa kwesigaba: γ→δ→θ→α-Al2O3, phakathi kwayo γ、δ、θ kukhona ukupakisha okuseduze kwe-cubic, umehluko usekusakazeni kwama-ion e-aluminium i-tetrahedral ne-octahedral, ngakho-ke lezi zinguquko zesigaba akubangeli ukuhlukahluka okuningi kwezakhiwo.Ama-ion oksijini asesigabeni se-alpha ane-hexagonal close packing, izinhlayiya ze-aluminium oxide ziwukuhlangana okukhulu, indawo ethile yehle kakhulu.
lGwema umswakama, gwema ukuskrola, ukujikijela kanye nokushaqeka okubukhali ngesikhathi sokuthutha, izinsiza ezingangenwa yimvula kufanele zilungiswe.
l Kufanele igcinwe endaweni yokugcina impahla eyomile nengena umoya ukuze kuvinjelwe ukungcoliswa noma umswakama.
