Kugwira Ntchito kwa Ufa wa Alumina Monga Chothandizira Chothandizira
Pokambirana za makampani opanga mankhwala, makamaka gawo la catalysis, pali zambiri. Masiku ano, sitilankhula za zigawo zachitsulo zogwira ntchito zapamwamba, zopindika lilime, koma m'malo mwake tikulankhula za "ngwazi yosayamikirika" yomwe nthawi zambiri imanyalanyazidwa koma yofunika kwambiri - ufa wa alumina. Uli ngati mzati wa siteji, kapena maziko a nyumba; momwe zigawo zogwira ntchito, "nyenyezi" zimenezo, zimagwirira ntchito bwino kumadalira momwe sitejiyo imamangidwira bwino.
Pamene ndinayamba kulowa m'munda uwu, ndinapezanso zachilendo—chifukwa chiyanialuminiyamumakamaka? Zikumveka zosadabwitsa, ndiye n’chifukwa chiyani zili ndi malo ofunikira kwambiri mumakampani othandizira ma catalyst? Pambuyo pake, nditakhala nthawi yayitali ndi ogwira ntchito odziwa bwino ntchito mu labu ndi workshop, pang'onopang'ono ndinayamba kumvetsetsa. Si chisankho "chabwino kwambiri", koma chisankho "choyenera kwambiri" chomwe chimapezeka pakati pa magwiridwe antchito, mtengo, ndi kugwiritsa ntchito moyenera. Izi zikufanana ndi kugula galimoto; sitifunikira galimoto yothamanga kwambiri, koma yomwe imalinganiza bwino mafuta, malo, kulimba, ndi mtengo. Mumakampani ogulitsa, alumina ali ngati "yonse" - zofooka zochepa komanso mphamvu zapadera.
Choyamba, tiyenera kuyamika ubwino wake wa "siponji yokhala ndi mabowo"—malo akuluakulu komanso kuthekera kwake kukula kwambiri.
Iyi ndiyo mphamvu yaikulu yaufa wa aluminaMusaganize kuti ndi mtanda wolimba komanso wokhuthala womwe mumagwiritsa ntchito kunyumba. Mukamaliza kukonza mwapadera, mkati mwa chonyamulira alumina mumakhala ndi ma micropores ndi ma channels pa nanoscale. Kapangidwe kameneka kamatchedwa "malo apadera kwambiri."
Mwachitsanzo, galamu imodzi ya ufa wa alumina wapamwamba kwambiri, ngati ma pores ake onse amkati akanakulitsidwa mokwanira, akanatha kufika mosavuta mamita mazana angapo pamwamba—okulirapo kuposa bwalo la basketball! Tangoganizirani kuchuluka kwa zinthu zogwira ntchito (monga platinamu, palladium, ndi nickel) zomwe zingagwiritsidwe ntchito mu "gawo" lalikulu chonchi! Zili ngati kupatsa zinthu zogwira ntchito "nyumba yogona" yayikulu kwambiri, yokonzedwa bwino, zomwe zimawathandiza kuti afalikire mofanana ndikupewa kusonkhana pamodzi, motero zimawonjezera kukhudzana kwawo ndi zinthu zoyambitsa. Izi zimatsimikizira kuti zinthu zoyambitsa zimagwira ntchito bwino.
Komanso, kapangidwe ka ma pore a "siponji" iyi kangathe "kusinthidwa." Mwa kusintha njira yokonzekera, titha kuwongolera kukula, kufalikira, ndi mawonekedwe a ma pore ake pamlingo winawake, mofanana ndi dongo loumba. Mamolekyu ena a reactant ndi akuluakulu ndipo amafuna "zitseko" zazikulu kuti alowe; machitidwe ena ndi achangu ndipo amafuna ma pore afupiafupi kuti asasocheretsedwe mu mazenera. Thandizo la alumina lingakwaniritse bwino "zosowa zaumwini" izi, kusinthasintha kosayerekezeka ndi zipangizo zina zambiri.
Kachiwiri, "khalidwe lake labwino" ndilofunika kutchula—lili ndi kukhazikika kwabwino kwa mankhwala komanso mphamvu ya makina.
Malo omwe ma catalyst amakhala si abwino kwenikweni. Nthawi zambiri amakhala otentha kwambiri komanso opanikizika, ndipo nthawi zina amakhudzanso mpweya wowononga. Tangoganizani ngati chothandiziracho chikanakhala "chandamale chofewa," chikugwa mkati mwa masiku awiri mu reactor, kapena chikuchita zinthu ndi zinthu zogwira ntchito komanso ma reactants - kodi zonse sizikanakhala zosokoneza?
Ufa wa alumina, pankhaniyi, ndi "wokhazikika" kwambiri. Umasunga kapangidwe kake ka kristalo ngakhale kutentha kwambiri, kulimbana ndi kugwa, ndipo mankhwala ake ndi "osalowerera," osagwira ntchito mosavuta ndi zinthu zina. Izi zimathandizira kuti catalyst ikhale ndi moyo wautali, zomwe zimapulumutsa mafakitale nthawi yopuma komanso ndalama zosinthira.
Komanso, taganizirani mphamvu ya makina. Mu ma reactor a mafakitale, ma catalyst samangoyikidwa chete; nthawi zambiri amafunika kupirira mphamvu ya mpweya, kukangana pakati pa tinthu tating'onoting'ono, komanso kugwa mkati mwa bedi loyenda. Ngati mphamvuyo si yokwanira, imasweka n’kukhala ufa ikangonyamulidwa, kapena kusanduka phulusa ikangolowa mu reactor—kodi ndi catalysis yotani yomwe ingapezeke?AluminaZothandizira, pambuyo poumba ndi kuyika calcination, zimakhala ndi mphamvu zokwanira kuti zipirire "kuzunzidwa" kumeneku, zomwe zimapangitsa kuti chipangizocho chigwire ntchito bwino kwa nthawi yayitali komanso mokhazikika. Izi ndi zomwe ogwira ntchito odziwa bwino ntchito amatanthauza akamanena kuti "chothandizira ichi ndi cholimba."
Komanso, ndi yolimba kwambiri—mawonekedwe ake pamwamba ndi amphamvu kwambiri.
Pamwamba pa alumina si posalala. Pali malo okhala ndi asidi kapena oyambira. Malo amenewa ali ndi mphamvu zoyambitsa zinthu zina. Chofunika kwambiri, amatha "kugwirizana" ndi chitsulo chogwira ntchito chomwe chimathandizidwa - chinthu chomwe timachitcha kuti kuyanjana.
Kuyanjana kumeneku kuli ndi ubwino wambiri. Kumbali imodzi, kumagwira ntchito ngati "guluu," kumamatira mwamphamvu tinthu tachitsulo ku chithandizo, kuletsa kusuntha, kusonkhana, ndikukula kutentha kwambiri (izi zimatchedwa sintering). Sintering ikachitika, ntchito yothandiza imachepa kwambiri. Kumbali ina, nthawi zina imatha kusintha momwe zinthu zamagetsi zimagwirira ntchito, zomwe zimapangitsa kuti zigwire bwino ntchito zothandiza, zomwe zimapangitsa kuti zikhale zogwirizana ndi "1+1>2".
Zachidziwikire, palibe chomwe chili changwiro. Zothandizira za alumina sizili zopanda zolakwika. Mwachitsanzo, m'malo otentha kwambiri okhala ndi nthunzi yamadzi, imatha kupitirira "kusintha kwa gawo," kusintha kuchoka pa mtundu wa γ wogwira ntchito kwambiri kupita ku mtundu wa α wosagwira ntchito kwambiri, zomwe zimapangitsa kuti kapangidwe ka ma pore kagwere komanso kuchepa kwakukulu kwa malo pamwamba. Izi zikufanana ndi mpweya woyatsidwa womwe umatenthedwa kukhala graphite; ngakhale ukadali kaboni, mphamvu yake yoyamwa ndi yosiyana kwambiri. Chifukwa chake, ofufuza akhala akugwira ntchito kuti akonze kukhazikika kwake kwa kutentha mwa kuigwiritsa ntchito ndi zinthu zina (monga silicon ndi zirconium) kapena kupanga njira zatsopano zokonzekera kuti ziwonjezere mphamvu zake ndikuchepetsa zofooka zake.
Kotero, mukuona, ufa woyera uwu womwe umawoneka ngati wamba uli ndi chidziwitso chochuluka. Si ukadaulo wakuda wosamvetsetseka, koma ndi mtundu uwu wa zinthu, womwe umayesetsa kukhala wolinganiza komanso wokonza bwino chilichonse, womwe umathandizira theka la makina amakono opangira zinthu zamagetsi. Kuyambira kuyeretsa utsi wa magalimoto mpaka kuphwanya ndikusintha mafuta, komanso kupanga zinthu zosiyanasiyana zopangira mankhwala, ntchito yopanda phokoso ya zonyamula alumina nthawi zambiri imawonekera kumbuyo kwa zochitika.
Sizimawala ngati zitsulo zamtengo wapatali monga platinamu kapena palladium, ndipo mtengo wake ndi wotsika kwambiri, koma kudalirika kwake, kulimba kwake, komanso kugwiritsa ntchito bwino ndalama kumapangitsa kuti ikhale maziko olimba kwambiri ogwiritsira ntchito mafakitale akuluakulu. Nthawi ina mukamva za kupita patsogolo kwa ukadaulo wothandiza, ipatseni ulemu, chifukwa alumina powder, ngwazi yosayamikirika kumbuyo kwa zochitika, iyenera kupatsidwa ulemu waukulu chifukwa cha kupambana kumeneku.