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 amasiyananso. Gamma activated alumina ndi kiyubiki chodzaza ndi krustalo, chosasungunuka m'madzi, koma chosungunuka 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 wopanda mpweya (pakati) ndi aluminiyamu (pakati pa acid), yokhala ndi ntchito yothandiza. Choncho, aluminiyamu angagwiritsidwe ntchito ngati chonyamulira, chothandizira ndi cocatalyst.
Gamma activated alumina ikhoza kukhala ufa, granules, mizere kapena zina. γ-Al2O3, ankatchedwa "adamulowetsa aluminiyamu", ndi mtundu wa porous mkulu kubalalitsidwa olimba zipangizo, chifukwa cha chosinthika pore dongosolo, lalikulu enieni pamwamba m'dera, zabwino adsorption ntchito, pamwamba ndi ubwino wa acidity ndi kukhazikika bwino matenthedwe, microporous pamwamba ndi katundu woyenerera chothandizira kanthu, choncho ntchito catalyst chothandizira kwambiri catalystography ndi catalystography. chonyamulira mu makampani mankhwala ndi mafuta, ndipo amatenga mbali yofunika kwambiri mu mafuta hydrocracking, hydrogenation kuyenga, hydrogenation reforming, dehydrogenation anachita ndi galimoto utsi kuyeretsa ndondomeko.Gamma-Al2O3 chimagwiritsidwa ntchito ngati chotengera chonyamulira chifukwa cha adjustability wa pore kapangidwe ndi acidity pamwamba. 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 aluminiyamu zambiri zopangidwa ndi kalambulabwalo wake pseudo-boehmite kudzera 400 ~ 600 ℃ mkulu 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 a pseudo-boehmite gamma-Al-boehmite-Al-Boehmite kutsogolera. 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 kumachitika zotsatirazi gawo kusintha: γ→ δ→ θ→ α-Al2O3, pakati pawo γ, δ, θ ndi kiyubiki pafupi kulongedza katundu, kusiyana kokha lagona mu kagawidwe ayoni zotayidwa mu tetrahedral ndi octahedral, kotero kusintha gawo la dongosolo si chifukwa kwambiri. 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.
