Alumina apezeka kuti alipo osachepera 8 mawonekedwe, ndi α- Al2O3, θ-Al2O3, γ- Al2O3, δ- Al2O3, η- Al2O3, χ- Al2O3, κ- Al2O3 ndi ρ- Al2O3, mawonekedwe awo a macroscopic nawonso ndi osiyana.Gamma activated alumina ndi kiyubiki yodzaza ndi krustalo, yosasungunuka m'madzi, koma imasungunuka mu asidi ndi alkali.Gamma adamulowetsa aluminiyamu ndi ofooka acidic thandizo, ali mkulu kusungunuka 2050 ℃, aluminiyamu gel osakaniza mu mawonekedwe hydrate akhoza kupangidwa okusayidi ndi mkulu porosity ndi pamwamba enieni enieni, ali ndi magawo kusintha mu osiyanasiyana kutentha.Pakutentha kwambiri, chifukwa cha kuchepa kwa madzi m'thupi ndi dehydroxylation, Al2O3surface imawoneka yolumikizana ndi okosijeni wosakwanira (pakati) ndi aluminiyamu (pakati pa asidi), yokhala ndi ntchito yothandiza.Chifukwa chake, alumina angagwiritsidwe ntchito ngati chonyamulira, chothandizira komanso cocatalyst.
Gamma activated alumina ikhoza kukhala ufa, granules, mizere kapena zina.Titha kuchita monga lamulo lanu.γ-Al2O3, amatchedwa "adamulowetsa aluminiyamu", ndi mtundu wa porous mkulu kubalalitsidwa olimba zipangizo, chifukwa cha chosinthika pore kapangidwe, lalikulu enieni pamwamba m'dera, ntchito zabwino adsorption, pamwamba ndi ubwino acidity. ndi zabwino matenthedwe bata, microporous pamwamba ndi katundu wofunika wa chothandizira kanthu, Choncho kukhala chothandizira ambiri ankagwiritsa ntchito, chothandizira chonyamulira ndi chromatography chonyamulira mu makampani mankhwala ndi mafuta, ndi mbali yofunika kwambiri mu mafuta hydrocracking, hydrogenation kuyenga, hydrogenation reforming, Gamma-Al2O3 imagwiritsidwa ntchito kwambiri ngati chonyamulira chothandizira chifukwa cha kusintha kwa ma pore ake komanso acidity yapamwamba.Pamene γ- Al2O3 ntchito monga chonyamulira, kuwonjezera akhoza kukhala ndi zotsatira kumwazikana ndi bata yogwira zigawo zikuluzikulu, komanso angapereke asidi zamchere yogwira likulu, synergistic anachita ndi chothandizira yogwira zigawo zikuluzikulu.Mapangidwe a pore ndi mawonekedwe a pamwamba a chothandizira amadalira chonyamulira cha γ-Al2O3, kotero chonyamulira chogwira ntchito kwambiri chingapezeke kuti chizithandizira poyang'anira katundu wa gamma alumina chonyamulira.
Gamma adamulowetsa alumina zambiri anapangidwa kalambulabwalo wake pseudo-boehmite kudzera 400 ~ 600 ℃ kutentha kutentha madzi m'thupi, kotero pamwamba physicochemical katundu makamaka anatsimikiza ndi kalambulabwalo wake pseudo-boehmite, koma pali njira zambiri kupanga pseudo-boehmite, ndi magwero osiyanasiyana. pseudo-boehmite imatsogolera ku mitundu yosiyanasiyana ya gamma - Al2O3.Komabe, kuti catalysts ndi zofunika wapadera kwa aluminiyamu chonyamulira, okha kudalira ulamuliro wa kalambulabwalo pseudo-boehmite n'zovuta kukwaniritsa, ayenera kumwedwa prophase kukonzekera ndi positi processing kaphatikizidwe njira kusintha katundu wa aluminiyamu kukwaniritsa zofunika zosiyanasiyana.Pamene kutentha ndi apamwamba kuposa 1000 ℃ ntchito, aluminiyamu zimachitika zotsatirazi gawo kusintha: γ→ δ→ θ→α-Al2O3, pakati pawo γ, δ, θ ndi kiyubiki pafupi kulongedza katundu, kusiyana kokha lagona mu kugawa ayoni zotayidwa mu tetrahedral ndi octahedral, kotero kusintha kwa gawoli sikumayambitsa kusiyanasiyana kwazinthuzo.Ma ion okosijeni mu gawo la alpha ndi hexagonal pafupi kulongedza, tinthu tating'onoting'ono ta aluminium oxide ndi kukumananso kwakukulu, kudera linalake kumatsika kwambiri.
l Pewani chinyezi, pewani kupukuta, kuponyera ndi kugwedeza mwamphamvu panthawi yamayendedwe, malo osagwa mvula akuyenera kukonzedwa.
lIyenera kusungidwa m'nkhokwe yowuma ndi mpweya wabwino kuti isaipitsidwe ndi chinyezi.
