Activated carbon (AC) amatanthauza zinthu zokhala ndi mpweya wambiri zomwe zimakhala ndi porosity kwambiri komanso sorption zomwe zimapangidwa kuchokera ku nkhuni, zipolopolo za kokonati, malasha, ndi ma cones, ndi zina. kuchokera kumadzi ndi mpweya. Popeza, AC yopangidwa kuchokera kuzinthu zaulimi ndi zinyalala, yakhala njira yabwino kwambiri yopangira zinthu zomwe sizingangowonjezeranso komanso zodula. Pokonzekera AC, njira ziwiri zoyambira, carbonization ndi activation, zimagwiritsidwa ntchito. Pachiyambi choyamba, ma precursors amatenthedwa kwambiri, pakati pa 400 ndi 850 ° C, kuti atulutse zigawo zonse zowonongeka. Kutentha kokwezeka kwambiri kumachotsa zinthu zonse zopanda kaboni pa kalambulabwalo monga haidrojeni, okosijeni, ndi nayitrojeni monga mipweya ndi phula. Izi zimapanga char chokhala ndi mpweya wambiri koma malo otsika komanso otsika. Komabe, sitepe yachiwiri ikukhudza kutsegulira kwa char yomwe idapangidwa kale. Kukulitsa kukula kwa pore panthawi yotsegulira kumatha kugawidwa m'magulu atatu: kutseguka kwa ma pores omwe sanafikikepo, kakulidwe kapore katsopano poyambitsa mwa kusankha, ndi kukulitsa kwa ma pores omwe analipo kale.
Nthawi zambiri, njira ziwiri, zakuthupi ndi zamankhwala, zimagwiritsidwa ntchito poyambitsa kuti apeze malo ofunikira komanso porosity. Kutsegula kwakuthupi kumaphatikizapo kuyatsa moto wa carbonized pogwiritsa ntchito mpweya woipa monga mpweya, carbon dioxide, ndi nthunzi pa kutentha kwakukulu (pakati pa 650 ndi 900 ° C). Mpweya woipa wa carbon dioxide nthawi zambiri umakondedwa chifukwa cha chikhalidwe chake choyera, kugwira kwake kosavuta, komanso njira yotsegula yozungulira 800 ° C. Kufanana kwa pore kumatha kupezeka ndi kuyambitsa kwa carbon dioxide poyerekeza ndi nthunzi. Komabe, poyambitsa thupi, nthunzi imakonda kwambiri poyerekeza ndi mpweya woipa chifukwa AC yokhala ndi malo okwera kwambiri imatha kupangidwa. Chifukwa cha kukula kwa molekyulu yamadzi, kufalikira kwake mkati mwa dongosolo la char kumachitika bwino. Kutsegula ndi nthunzi kwapezeka kuti ndikokwera kawiri kapena katatu kuposa mpweya woipa womwe uli ndi kutembenuka kofanana.
Komabe, njira yamankhwala imaphatikizapo kusakanikirana kwa kalambulabwalo ndi ma activate agents (NaOH, KOH, ndi FeCl3, etc.). Ma activate awa amagwira ntchito ngati ma oxidants komanso dehydrating agents. Mwa njira iyi, carbonization ndi kutsegula kumachitika nthawi imodzi pa kutentha kochepa 300-500 ° C poyerekeza ndi njira yakuthupi. Zotsatira zake, zimakhudza kuwonongeka kwa pyrolytic ndipo, kenaka, kumabweretsa kukula kwa mapangidwe a porous ndi kutulutsa mpweya wambiri. Ubwino waukulu wamankhwala potengera momwe thupi limayendera ndi kutentha kocheperako, mawonekedwe a microporosity, malo akulu, komanso nthawi yocheperako.
Kupambana kwa njira yopangira mankhwala kumatha kufotokozedwa pamaziko a chitsanzo chomwe Kim ndi ogwira nawo ntchito [1] malinga ndi momwe ma microdomain osiyanasiyana ozungulira omwe amapanga ma micropores amapezeka mu AC. Kumbali ina, ma mesopores amapangidwa m'magawo a intermicrodomain. Moyesera, adapanga activated carbon kuchokera ku phenol-based resin ndi mankhwala (pogwiritsa ntchito KOH) ndi thupi (pogwiritsa ntchito nthunzi) kutsegula (Chithunzi 1). Zotsatira zinawonetsa kuti AC yopangidwa ndi kutsegulira kwa KOH inali ndi malo okwera kwambiri a 2878 m2/g poyerekeza ndi 2213 m2/g ndi kuyatsa kwa nthunzi. Kuphatikiza apo, zinthu zina monga kukula kwa pore, malo ozungulira, kuchuluka kwa ma micropore, komanso kuchuluka kwa pore m'lifupi zonse zidapezeka kuti ndizabwinoko pamikhalidwe yoyatsidwa ndi KOH poyerekeza ndi mpweya woyatsidwa.
Kusiyana pakati pa AC Yokonzeka kuchokera pakuyatsa nthunzi(C6S9) ndi kuyambitsa kwa KOH(C6K9), motsatana, kufotokozedwa motengera mtundu wa microstructure.
Kutengera kukula kwa tinthu ndi njira yokonzekera, imatha kugawidwa m'mitundu itatu: yoyendetsedwa ndi AC, granular AC, ndi bead AC. Mphamvu ya AC imapangidwa kuchokera ku ma granules abwino okhala ndi kukula kwa 1 mm ndi mainchesi osiyanasiyana a 0.15-0.25 mm. Granular AC ili ndi kukula kwake kokulirapo komanso malo ochepa akunja. Granular AC imagwiritsidwa ntchito pazinthu zosiyanasiyana zamadzimadzi ndi gawo la mpweya kutengera kukula kwawo. Gulu lachitatu: mikanda ya AC nthawi zambiri imapangidwa kuchokera kumafuta amafuta okhala ndi mainchesi kuyambira 0.35 mpaka 0.8 mm. Amadziwika ndi mphamvu zake zamakina apamwamba komanso fumbi lochepa. Amagwiritsidwa ntchito kwambiri pamabedi amadzimadzi monga kusefera kwamadzi chifukwa cha mawonekedwe ake ozungulira.
Nthawi yotumiza: Jun-18-2022