An gano cewa alumina tana wanzuwa aƙalla nau'i 8, su ne α- Al2O3, θ-Al2O3, γ- Al2O3, δ- Al2O3, η- Al2O3, χ- Al2O3, κ- Al2O3 da ρ- Al2O3, halayen tsarin macroscopic ɗinsu suma sun bambanta. Alumina mai aiki da Gamma lu'ulu'u ne mai siffar cubic closed, wanda ba ya narkewa a cikin ruwa, amma yana narkewa a cikin acid da alkali. Alumina mai aiki da Gamma yana da rauni mai tallafawa acid, yana da babban wurin narkewa 2050 ℃, ana iya yin gel ɗin alumina a cikin siffa mai hydrate zuwa oxide tare da babban porosity da babban saman takamaiman, yana da matakan sauyawa a cikin kewayon zafin jiki mai faɗi. A mafi yawan zafin jiki, saboda bushewa da dehydroxylation, saman Al2O3 yana bayyana daidaituwar iskar oxygen mara cikawa (cibiyar alkaline) da aluminum (cibiyar acid), tare da aikin catalytic. Saboda haka, ana iya amfani da alumina azaman mai ɗaukar kaya, mai haɓaka da cocatalyst.
Alumina mai aiki da Gamma na iya zama foda, granules, tubes ko wasu. Za mu iya yin kamar yadda kuke buƙata. γ-Al2O3, wanda aka kira "alumina mai kunnawa", wani nau'in kayan aiki ne mai ƙarfi mai ramuka masu ramuka, saboda tsarin ramuka masu daidaitawa, babban yanki na musamman, kyakkyawan aikin sha, saman tare da fa'idodin acidity da kwanciyar hankali mai kyau na zafi, saman microporous tare da halayen da ake buƙata na aikin catalytic, don haka ya zama mai kara kuzari, mai ɗaukar catalyst da mai ɗaukar chromatography mafi amfani a masana'antar sinadarai da mai, kuma yana taka muhimmiyar rawa a cikin hydrocracking na mai, sake fasalin hydrogenation, gyaran hydrogenation, dehydrogenation reaction da tsarin tsarkake hayaki na mota. Ana amfani da Gamma-Al2O3 sosai azaman mai ɗaukar catalyst saboda daidaitawar tsarin ramuka da acidity na saman. Lokacin da aka yi amfani da γ-Al2O3 azaman mai ɗaukar kaya, baya ga haka yana iya samun tasirin warwatsewa da daidaita abubuwan aiki, kuma yana iya samar da cibiyar aiki mai aiki da alkali na acid, amsawar haɗin gwiwa tare da abubuwan aiki masu aiki na catalytic. Tsarin rami da kuma yanayin saman mai kara kuzari sun dogara ne akan mai ɗaukar γ-Al2O3, don haka za a sami mai ɗaukar nauyi mai aiki mai kyau don takamaiman amsawar mai kara kuzari ta hanyar sarrafa halayen mai ɗaukar gamma alumina.
Alumina mai kunna gamma galibi ana yin ta ne da pseudo-boehmite mai riga-kafi har zuwa digiri 400 ~ 600℃, don haka kaddarorin sinadaran saman galibi ana ƙaddara su ne ta hanyar pseudo-boehmite mai riga-kafi, amma akwai hanyoyi da yawa don yin pseudo-boehmite, kuma tushen daban-daban na pseudo-boehmite yana haifar da bambancin gamma - Al2O3. Duk da haka, ga waɗannan abubuwan haɓaka masu buƙatu na musamman ga mai ɗaukar alumina, kawai dogara ne akan ikon pseudo-boehmite mai riga-kafi yana da wahalar cimmawa, dole ne a ɗauki hanyar shiryawa da haɗa hanyoyin haɗa abubuwa bayan sarrafawa don daidaita halayen alumina don biyan buƙatu daban-daban. Lokacin da zafin jiki ya fi 1000 ℃ da ake amfani da shi, alumina yana faruwa bayan canjin mataki: γ→δ→θ→α-Al2O3, daga cikinsu γ、δ、θ sune marufi mai siffar cubic, bambancin yana cikin rarraba ions na aluminum a cikin tetrahedral da octahedral, don haka waɗannan canjin lokaci baya haifar da bambancin tsarin sosai. Ion oxygen a cikin matakin alpha suna rufewa da hexagonal, barbashi na aluminum oxide sun sake haɗuwa sosai, takamaiman yankin saman ya ragu sosai.
A guji danshi, a guji gungurawa, jifa da girgiza kai yayin jigilar kaya, ya kamata a shirya wuraren da za su iya jure ruwan sama.
Ya kamata a adana shi a cikin busasshiyar ma'ajiyar kayan ajiya mai iska domin hana gurɓatawa ko danshi.
