I-Cellulose iyi-polysaccharide eyinkimbinkimbi eyakhiwe amayunithi amaningi e-glucose axhunywe ngamabhondi e-β-1,4-glycosidic. Iyingxenye eyinhloko yezindonga zamaseli ezitshalo futhi inikeza izindonga zamaseli ezitshalo ukwesekwa okuqinile kwesakhiwo kanye nokuqina. Ngenxa yochungechunge olude lwamangqamuzana e-cellulose kanye nokucwebezela okuphezulu, inokuqina okuqinile nokungancibiliki.
(1) Izakhiwo ze-cellulose nobunzima bokuhlakazeka
I-Cellulose inezici ezilandelayo ezenza kube nzima ukuncibilika:
I-crystallinity ephezulu: Amaketango e-cellulose amangqamuzana akha isakhiwo se-lattice esiqinile ngamabhondi e-hydrogen namandla e-van der Waals.
Izinga eliphezulu le-polymerization: Izinga le-polymerization (okungukuthi ubude beketango lamangqamuzana) we-cellulose liphezulu, ngokuvamile lisukela kumakhulu kuya ezinkulungwaneni zamayunithi e-glucose, okwandisa ukuzinza kwe-molecule.
Inethiwekhi yebhondi ye-Hydrogen: Amabhondi e-Hydrogen akhona kabanzi phakathi nangaphakathi kwamaketanga e-cellulose yamangqamuzana, okwenza kube nzima ukuchithwa nokuchithwa yizincibilikisi ezivamile.
(2) Ama-reagents ancibilikisa i-cellulose
Njengamanje, ama-reagents aziwayo angancibilikisa ngempumelelo i-cellulose ikakhulukazi ahlanganisa lezi zigaba ezilandelayo:
1. Ionic Liquids
Uketshezi lwe-ionic uketshezi oluhlanganiswe ama-organic cations nama-anion aphilayo noma angaphili, ngokuvamile anokuguquguquka okuphansi, ukuzinza okuphezulu kwe-thermal kanye nokulungiswa okuphezulu. Olunye uketshezi lwe-ionic lungancibilikisa i-cellulose, futhi indlela eyinhloko ukuphula izibopho ze-hydrogen phakathi kwamaketanga e-cellulose yamangqamuzana. Iziphuzo ezivamile ze-ionic ezincibilikisa i-cellulose zihlanganisa:
I-1-Butyl-3-methylimidazolium chloride ([BMIM]Cl): Lolu ketshezi lwe-ionic luncibilikisa i-cellulose ngokusebenzisana namabhondi e-hydrogen ku-cellulose ngezamukeli ze-hydrogen bond.
I-1-Ethyl-3-methylimidazolium acetate ([EMIM][Ac]): Lolu ketshezi lwe-ayoni lungancibilikisa ukugxila okuphezulu kwe-cellulose ngaphansi kwezimo ezithambile.
2. Isixazululo se-amine oxidant
Isixazululo se-amine oxidant njengengxube ye-diethylamine (DEA) ne-copper chloride ibizwa ngokuthi [Cu(II)-ammonium solution], okuwuhlelo oluqinile lokuncibilikisa olungancibilikisa i-cellulose. Ibhidliza ukwakheka kwekristalu ye-cellulose ngokusebenzisa i-oxidation ne-hydrogen bonding, okwenza iketango lamangqamuzana e-cellulose lithambe futhi lincibilike kakhudlwana.
3. Uhlelo lwe-Lithium chloride-dimethylacetamide (LiCl-DMAC).
Uhlelo lwe-LiCl-DMAc (lithium chloride-dimethylacetamide) lungenye yezindlela zakudala zokuncibilikisa i-cellulose. I-LiCl ingakha umncintiswano wamabhondi e-hydrogen, ngaleyo ndlela ibhubhise inethiwekhi yebhondi ye-hydrogen phakathi kwama-molecule e-cellulose, kuyilapho i-DMAc njenge-solvent ingasebenzisana kahle neketango lamangqamuzana e-cellulose.
4. Isixazululo se-Hydrochloric acid/zinc chloride
Isixazululo se-hydrochloric acid/zinc chloride siyinto etholwe ngokushesha engancibilikisa i-cellulose. Ingancibilikisa i-cellulose ngokwenza umphumela wokuxhumanisa phakathi kwe-zinc chloride namaketanga e-cellulose yamangqamuzana, kanye ne-hydrochloric acid ebhubhisa izibopho ze-hydrogen phakathi kwama-molecule e-cellulose. Kodwa-ke, lesi sixazululo sigqwala kakhulu ezintweni zokusebenza futhi sinqunyelwe ekusebenzeni okungokoqobo.
5. Ama-enzyme e-Fibrinolytic
Ama-enzyme e-Fibrinolytic (njengama-cellulase) ancibilikisa i-cellulose ngokudala ukubola kwe-cellulose ibe ama-oligosaccharides amancane nama-monosaccharides. Le ndlela inezinhlobonhlobo zezinhlelo zokusebenza emkhakheni we-biodegradation kanye nokuguqulwa kwe-biomass, nakuba inqubo yayo yokuqedwa ingekona ukuqedwa kwamakhemikhali ngokuphelele, kodwa itholakala nge-biocatalysis.
(3) Indlela yokuchithwa kwe-cellulose
Ama-reagents ahlukene anezindlela ezihlukene zokuhlakaza i-cellulose, kodwa ngokuvamile angabangelwa izindlela ezimbili eziyinhloko:
Ukucekelwa phansi kwamabhondi e-hydrogen: Ukucekela phansi izibopho ze-hydrogen phakathi kwamaketanga e-cellulose yamangqamuzana ngokwakhiwa kwebhondi ye-hydrogen ngokuncintisana noma ukusebenzisana kwe-ionic, kuyenze inyibilike.
Ukuphumula kweketango lamangqamuzana: Ukwandisa ukuthamba kwamaketanga engqamuzana ye-cellulose kanye nokunciphisa ukucwebezela kwamaketanga amangqamuzana ngokusebenzisa izinto ezibonakalayo noma zamakhemikhali, ukuze akwazi ukuncibilika kuzincibilikisi.
(4) Ukusetshenziswa okusebenzayo kokuchithwa kwe-cellulose
Ukuqedwa kweCellulose kunezinhlelo zokusebenza ezibalulekile emikhakheni eminingi:
Ukulungiswa kwe-cellulose derivatives: Ngemva kokuqedwa kwe-cellulose, ingabuye iguqulwe amakhemikhali ukuze kulungiswe ama-cellulose ethers, ama-cellulose esters nezinye izinto eziphuma kuzo, ezisetshenziswa kakhulu ekudleni, emithini, ekwembathweni nakweminye imikhakha.
Izinto ezisekelwe ku-cellulose: Kungasetshenziswa i-cellulose encibilikisiwe, ama-cellulose nanofibers, ulwelwesi lwe-cellulose nezinye izinto zingalungiswa. Lezi zinto zinezici ezinhle zemishini kanye ne-biocompatibility.
Amandla e-biomass: Ngokuncibilikisa kanye nokululaza i-cellulose, ingaguqulwa ibe ushukela ovutshelwayo ukuze kukhiqizwe ama-biofuels afana ne-bioethanol, esiza ukufeza ukuthuthukiswa nokusetshenziswa kwamandla avuselelekayo.
Ukuqedwa kwe-cellulose kuyinqubo eyinkimbinkimbi ehlanganisa izindlela eziningi zamakhemikhali nezomzimba. Uketshezi lwe-ionic, izixazululo ze-amino oxidant, izinhlelo ze-LiCl-DMAc, izixazululo ze-hydrochloric acid/zinc chloride kanye nama-enzyme e-cellolytic okwamanje aziwa njengama-ejenti asebenzayo ekuncibilikiseni i-cellulose. I-ejenti ngayinye inendlela yayo ehlukile yokuhlakaza kanye nenkundla yesicelo. Ngocwaningo olunzulu lwendlela yokuchithwa kwe-cellulose, kukholakala ukuthi kuzothuthukiswa izindlela zokuhlakaza ezisebenza kahle nezinobungani nemvelo, okuhlinzeka ngamathuba amaningi okusetshenziswa nokuthuthukiswa kwe-cellulose.
Isikhathi sokuthumela: Jul-09-2024