Kushanda kweAlumina Powder seCatalyst Support
Pakukurukura nezveindasitiri yemakemikari, kunyanya nyaya ye catalysis, pane zvakawanda zviripo. Nhasi, hatizotauri nezvezvinhu zvesimbi zvinoshanda zvine hunyanzvi, asi nezve "gamba risingaimbwe" rinowanzo furatirwa asi risingakoshi zvachose - alumina powder. Zvakafanana nembiru yechikuva, kana nheyo yechivako; kuti zvinhu zvinoshanda, "nyeredzi" idzodzo, zvinoshanda zvakanaka sei zvinoenderana nekuti chikuva chacho chakavakwa zvakanaka sei.
Pandakatanga kupinda mumunda uyu, ndakaonawo zvisinganzwisisike—seialuminazvakananga? Zvinonzwika sezvisingashamisi, saka sei zvichitora nzvimbo yakakosha muindasitiri yekutsigira catalyst? Gare gare, mushure mekupedza nguva yakareba nevashandi vane ruzivo murabhoritari neworkshop, ndakazonzwisisa zvishoma nezvishoma. Haisiriyo sarudzo "yakanakisa", asi sarudzo "yakanyanya kuenzana" inowanikwa pakati pekushanda, mutengo, uye mashandisirwo anoshanda. Izvi zvakafanana nekutenga mota; hatidi mota inokurumidza, asi inoda inoenzanisa kushanda zvakanaka kwemafuta, nzvimbo, kugara kwenguva refu, uye mutengo. Muindasitiri yekutakura, alumina yakafanana neiyo "yakazara" - kushomeka kushoma uye simba rakakura.
Kutanga, tinofanira kurumbidza hunhu hwayo hwe "sponge ine maburi" - nzvimbo yakakura uye mukana wekukura wakakwira zvikuru.
Iri ndiro simba guru reupfu hwealuminaUsazvifungidzira semukanyiwa wakaoma, wakaoma waunoshandisa kumba. Mushure mekugadziriswa kwakakosha, mukati memuchina wekutakura alumina mune ma micropores nema channels pa nanoscale. Chimiro ichi chinonzi "nzvimbo yepamusoro chaiyo."
Semuenzaniso, gramu imwe chete yeupfu hwealumina hwemhando yepamusoro, dai maburi ayo ese emukati akawedzerwa zvizere, aizosvika nyore nyore mazana emamita emativi mana pamusoro penzvimbo—yakakura kupfuura nhandare yebasketball! Fungidzira kuti zvinhu zvingani zvinoshanda (zvakaita seplatinum, palladium, uye nickel) zvinogona kuiswa mu "nzvimbo" yakakura kudaro! Zvakafanana nekupa zvinhu zvinoshanda "dhomitari" hombe kwazvo, yakashongedzwa zvakanaka, zvichivabvumira kupararira zvakaenzana uye kudzivirira kusangana pamwe chete, nokudaro zvichiwedzera kusangana kwavo uye kusangana nezvinokonzeresa. Izvi zvinovimbisa kushanda zvakanaka kwezvinokonzeresa.
Uyezve, chimiro cheburi re "sponge" iyi chinogona "kugadziriswa." Nekugadzirisa maitiro ekugadzirira, tinogona kudzora saizi, kupararira, uye chimiro cheburi rayo kusvika pamwero wakati, sekuumba ivhu. Mamwe mamorekuru anoita reactant akakura uye anoda "masuo" makuru kuti apinde; mamwe maitiro anokurumidza uye anoda maburi mapfupi kuti asarasike mumaze. Rutsigiro rwealumina runogona kusangana zvakakwana ne "zvinodiwa zvemunhu oga," kushanduka kusingaenzaniswi nezvimwe zvinhu zvakawanda.
Chechipiri, "hunhu hwayo hwakanaka" hwakakodzera kutaurwa—ine kugadzikana kwakanaka kwemakemikari uye simba remuchina.
Nzvimbo inogara zvinhu zvinokonzeresa hadzina kugadzikana. Kazhinji inopisa zvakanyanya uye kumanikidzwa, uye dzimwe nguva zvinotosanganisira kusangana nemagasi anoparadza. Fungidzira dai rutsigiro pacharwo rwaive "chinhu chakapfava," chichiputsika mukati memazuva maviri mureactor, kana kuti chichisangana nemakemikari nezvinhu zvinoshanda uye zvinokonzeresa—zvinhu zvese zvaisazova munyonganyonga here?
Upfu hweAlumina, panyaya iyi, "hwakasimba" zvinoshamisa. Hunochengetedza chimiro chayo chekristaro kunyangwe pakupisa kwakanyanya, huchiramba kudonha, uye hunhu hwayo hwemakemikari "hahuna kwahwakarerekera," hahukurumidzi kusangana nezvimwe zvinhu. Izvi zvinovimbisa hupenyu hwakareba hwechikafu, zvichichengetedza mafekitori nguva yakawanda yekusashanda uye mari yekutsiva.
Uyezve, funga nezvesimba remakanika. Muma "reactors" emaindasitiri, ma "catalysts" haangogadziki pasi chete; anowanzo fanira kutsungirira kukanganiswa kwemhepo, kukweshana pakati pezvikamu, uye kutodonha mukati memubhedha unofamba. Kana simba racho risina kukwana, rinopwanyika kuita upfu panguva yekufambisa, kana kuti rinoshanduka kuita dota kana rangopinda mu "reactor"—chii chingaitwa kuti chiite kuti zvinhu zviitike?AluminaZvitsigiro, mushure mekuumbwa nekuchekwa kwesimbi, zvinokura simba rakakwana rekutsungirira "kutambudzwa uku," zvichiita kuti chishandiso chekugadzirisa chishande kwenguva refu uye zvakagadzikana. Izvi ndizvo zvinorehwa nevashandi vane ruzivo pavanoti "chinokonzeresa ichi chakasimba."
Uyezve, inotsungirira zvakanyanya—hunhu hwayo hwepamusoro hunoshanda zvikuru.
Pamusoro pealumina hapasi panyoro. Pamwe pane acidic kana kuti nzvimbo dzakakosha. Nzvimbo idzi pachadzo dzine simba rekugadzirisa mamwe maitiro. Chinonyanya kukosha ndechekuti dzinogona "kubatana" nesimbi inoshanda inotsigirwa - chiitiko chatinodaidza kuti interaction.
Kudyidzana uku kune mabhenefiti akawanda. Kune rumwe rutivi, kunoshanda se "glue," kuchibatirira zvakasimba "zvimedu zvesimbi kukutsigira, kuchidzivisa kufamba, kuungana, uye kukura pakupisa kwakanyanya (izvi zvinonzi sintering). Kana sintering yaitika, basa re catalytic rinoderera zvakanyanya. Kune rumwe rutivi, dzimwe nguva rinogona kuchinja mamiriro emagetsi ezvimedu zvesimbi, zvichiita kuti zvishande zviri nani mu catalytic reactions, zvichiwana synergistic effect ye "1+1>2".
Ehe, hapana chakakwana. Zvitsigiro zveAlumina hazvinawo zvikanganiso. Semuenzaniso, munzvimbo dzinopisa zvakanyanya dzine utsi hwemvura, inogona kupinda mu "phase transition," ichichinja kubva kumhando yeγ inoshanda zvakanyanya kuenda kumhando yeα isingashande zvakanyanya, zvichikonzera kuparara kwechimiro chepore uye kudzikira kwakanyanya kwenzvimbo yepamusoro. Izvi zvakafanana nekupiswa kwekabhoni yakakangwa kuita graphite; kunyangwe ichiri kabhoni, kugona kwayo kunyudza kwakasiyana zvakanyanya. Nokudaro, vaongorori vanga vachishanda kuti vavandudze kugadzikana kwayo kwekupisa nekuisanganisa nezvimwe zvinhu (senge silicon ne zirconium) kana kugadzira maitiro matsva ekugadzirira kuti iwedzere simba rayo uye kuderedza kusasimba kwayo.
Saka, munoona, iyi upfu chena inoita kunge yakajairika ine ruzivo rwakakura. Haisi tekinoroji nhema isinganzwisiswi, asi ndiyo chaiyo mhando yezvinhu izvi, ichiedza kuenzana uye kugadzirisa zvese, inotsigira hafu yehurongwa hwemazuva ano hwemaindasitiri. Kubva pakuchenesa utsi hwemotokari kusvika pakupwanya nekugadzira peturu, uye kugadzira zvinhu zvakasiyana-siyana zvemakemikari, basa rakanyarara rekutakura alumina rinowanzoonekwa kuseri kwezviitiko.
Haipenye sesimbi dzinokosha dzakadai seplatinum kana palladium, uye mutengo wayo wakaderera zvikuru, asi kuvimbika kwayo, kugara kwenguva refu, uye kushanda kwayo zvakanaka kunoita kuti ive hwaro hwakasimba hwekushandiswa kwemaindasitiri makuru. Nguva inotevera paunonzwa nezvekubudirira mune tekinoroji ye catalytic, ipe pfungwa dzako, nekuti alumina powder, gamba risingazivikanwe riri kumashure kwezviitiko, rinofanira kurumbidzwa zvikuru nekuda kwekubudirira uku.