Esifundweni esishaqisayo, abacwaningi bahlole ukusebenza kahle kwezimpushana zesihlungo sama-molecule ezahlukahlukene emkhakheni wokucindezela intuthu. Ucwaningo lugxile ezinhlakeni ezahlukene zesihlungo sama-molecule, okuhlanganisa i-3A, 5A, 10X, 13X, NaY, MCM-41-Al, kanye ne-MCM-41-Si, okuhloswe ngazo ukuthola amandla azo ekunciphiseni ukukhishwa okuyingozi ngesikhathi sezinqubo zezimboni.
Ukususwa komusi kuyinto ebaluleke kakhulu ezimbonini eziningi, ikakhulukazi lezo ezihilela imisebenzi yokushisa okuphezulu njengokusebenza ngensimbi, ukushisela, kanye nokukhiqizwa kwamakhemikhali. Ukukhishwa komusi kungadala izingozi ezinkulu zempilo kubasebenzi futhi kufake isandla ekungcolisweni kwemvelo. Ngakho-ke, isidingo sezindlela zokucindezela ezisebenzayo asikaze sibe sikhulu kangaka.
Izisefo zama-molecule ziyizinto ezicwebezelayo ezinobukhulu obufanayo be-pore ezingamunca ama-molecule ngokukhetha ngokusekelwe kusayizi nesimo sawo. Lesi sici esiyingqayizivele siwenza abe ngabantu abafanelekile bezicelo ezahlukahlukene, okuhlanganisa ukuhlukaniswa kwegesi, i-catalysis, kanye, njengoba lolu cwaningo lusikisela, ukucindezela intuthu. Abacwaningi bafuna ukuhlola ukusebenza kwezimpuphu ezahlukene zesisefo sama-molecule ekubambeni nasekunciphiseni intuthu eyingozi.
Ucwaningo luqale ngokubuyekezwa okubanzi kwezakhiwo zezisefo zama-molecule ezikhethiwe. Izisefo ze-3A kanye ne-5A, ezaziwa ngekhono lazo lokumunca ama-molecule amancane, zahlolwa eceleni kwezisefo ezinkulu ze-pore, njenge-10X kanye ne-13X, ezingamukela ama-molecule amakhulu egesi. Isisefo se-NaY, uhlobo lwe-zeolite, naso safakwa ngenxa yendawo yaso ephezulu kanye namakhono okushintshana kwama-ion. Ngaphezu kwalokho, izinhlobo ze-MCM-41, i-MCM-41-Al kanye ne-MCM-41-Si, zakhethwa ngenxa yezakhiwo zazo ezihlukile ze-mesoporous, ezinikeza indlela ehlukile yokumunca uma kuqhathaniswa nama-zeolite endabuko.
Isigaba sokuhlola sasihilela ukufaka izimpushana zesihlungo sama-molecule ezinqubweni ezahlukahlukene zokukhiqiza intuthu, ukulingisa izimo ezivame ukutholakala ezindaweni zezimboni. Abacwaningi balinganise ukusebenza kahle kwesihlungo ngasinye ekubambeni intuthu, bahlaziya izici ezifana nomthamo wokumunca, izinga lokubamba intuthu, kanye nokusebenza kahle kokunciphisa amazinga ezinto eziyingozi emoyeni.
Imiphumela yokuqala ibonise ukuthi ukusebenza kwezisefo zama-molecule kwahlukahluka kakhulu ngokusekelwe ekwakhekeni nasekuhlelekeni kwazo. Izisefo ze-3A kanye ne-5A zibonise amakhono amangalisayo ekumunceni izinhlayiya ezincane zomusi, okwenza zifanelekele ukusetshenziswa lapho izinto ezincane ziyinkinga. Ngokuphambene nalokho, izisefo ezinkulu ze-pore, ikakhulukazi i-10X kanye ne-13X, ziphumelele kakhulu ekubambeni ama-molecule amakhulu egesi, okuphakamisa ukusetshenziswa kwazo okungenzeka ezinqubweni ezikhiqiza umusi osindayo.
Isihlungo se-NaY sibonise izakhiwo eziphawulekayo zokushintshana kwama-ion, ezingagcini nje ngokuthuthukisa ukusebenza kahle kokubamba intuthu kodwa futhi zavumela ukuncishiswa kwamakhemikhali athile anobuthi. Lesi sici sibeka i-NaY njengomuntu othembisayo embonini ebhekene nezinto eziyingozi, lapho kokubili ukucindezelwa kwentuthu kanye nokuncishiswa kwamakhemikhali kubalulekile.
I-MCM-41-Al kanye ne-MCM-41-Si, ngezakhiwo zazo ezihlukile ezingabonakali, zinikeze indlela ehlukile yokunciphisa intuthu. Indawo yazo ephezulu kanye nobukhulu bemibhobho elungisekayo kwavumela ukumuncwa okukhethiwe kwezingxenye ezithile zentuthu, okwenza kwaba izinketho eziguquguqukayo zamasu okuphatha intuthu aqondiwe. Ucwaningo luqokomise amandla alezi zinto ekuthuthukiseni izinhlelo zokuhlunga ezithuthukisiwe ezingakwazi ukuzivumelanisa nezidingo zezimboni ezahlukahlukene.
Njengoba ucwaningo luqhubeka, ithimba liphinde lahlola amakhono okuvuselela ama-molecular seeves. Amandla okubuyisela amandla okumunca ama-seeves ngemva kokusetshenziswa abalulekile ekusetshenzisweni kwawo okusebenzayo ezindaweni zezimboni. Ucwaningo luthole ukuthi iningi lama-seeves avivinyiwe lingavuselelwa ngempumelelo ngokwelashwa ngokushisa, okuvumela ukusetshenziswa okuphindaphindiwe ngaphandle kokulahlekelwa okukhulu kokusebenza.
Imiphumela yalolu cwaningo idlulela ngale kokucindezela intuthu nje. Ngokubona nokwenza ngcono ukusetshenziswa kwezimpushana zesihlungo sama-molecular, izimboni zinganciphisa kakhulu ukuthinteka kwazo kwemvelo futhi zithuthukise ukuphepha emsebenzini. Okutholakele kusikisela ukuthi ukuhlanganisa lezi zinto ezinhlelweni zokuphatha intuthu ezikhona kungaholela emikhubeni ephumelelayo neqhubekayo.
Ekuphetheni, lolu cwaningo olusha lukhanyisa amandla ezimpushana zesihlungo sama-molecule njengezinto ezisebenzayo zokucindezela intuthu. Ngezakhiwo zazo ezihlukile kanye namakhono, izihlungi ezifana ne-3A, 5A, 10X, 13X, NaY, MCM-41-Al, kanye ne-MCM-41-Si zinikeza izixazululo ezithembisayo ezinseleleni ezibangelwa ukukhishwa kwentuthu okuyingozi ezinqubweni zezimboni. Njengoba izimboni ziqhubeka nokufuna imikhuba yokusebenza eqhubekayo nephephile, ukuqonda okutholakale kulolu cwaningo kungavula indlela yokuthuthukiswa kobuchwepheshe obuphambili bokuphathwa kwentuthu obubeka phambili kokubili impilo kanye nokuvikelwa kwemvelo. Ucwaningo olwengeziwe kanye nokubambisana phakathi kwezemfundo kanye nemboni kuzobaluleka ukuhumusha lokhu okutholakele kube yizicelo ezisebenzayo, ekugcineni kube negalelo endaweni yezimboni ehlanzekile nephephile.
Isikhathi sokuthunyelwe: Disemba 19-2024
