I-Cellulose iyi-polysaccharide eyinkimbinkimbi eyakhiwe ngamayunithi amaningi we-glucose axhumeke ama-β-1,4-glycosidic bond. Yingxenye esemqoka yezindonga zeseli yezitshalo futhi inikeze izitshalo zamaseli ezindonga eziqinile zokusekelwa kwesakhiwo kanye nokuqina. Ngenxa ye-cellulose ende ye-cellulose chain kanye ne-crystallity ephezulu, inokuqina okuqinile futhi i-insoluble.
(1) Izakhiwo ze-cellulose nobunzima ekuchitheni
I-Cellulose inezinto ezilandelayo ezenza kube nzima ukuncibilikisa:
I-Crystallity ephezulu: Amaketanga we-cellulose molecular amaketanga akha isakhiwo esiqinile sama-hydrogen kanye namabutho we-van der Waals.
I-degree degree of polymerization: Izinga le-polymerization (okungukuthi ubude be-chain yamangqamuzana) ye-cellulose ephezulu, imvamisa isuka kumakhulu kuya ezinkulungwaneni zamanyusi, andisa ukuqina kwe-molecule.
I-Hydrogen Bond Network: Amabhondi e-Hydrogen akhona kakhulu phakathi nangaphakathi kwamaketanga ama-molecular ama-cellulose, okwenza kube nzima ukuchithwa futhi kuchithwe ngama-solvents ajwayelekile.
(2) ama-reagents ancibilikisa iselula
Njengamanje, ama-reagents owaziwayo angancibilikisa ngempumelelo i-cellulose ikakhulukazi ifaka phakathi izigaba ezilandelayo:
1. Ama-Ionic Liquid
Ama-Ionic Liquid asetshenziswa ama-organic ama-organic ama-organic kanye nama-organic noma ama-anions we-organic noma ama-inorganic, imvamisa ngokuqina okuphansi, ukuqina okuphezulu okushisayo kanye nokuqina okuphezulu. Amanye ama-ionic ketshezi angancibilikisa iselula, futhi indlela esemqoka ukuphula ama-hydrogen bond phakathi kwamaketanga ama-cellulose molecular amaketanga. Iziphuzo ezijwayelekile ze-Ionic ezincibilika iselula kufaka phakathi:
I-1-Butyl-3-methylimidazolium chloride ([BMIM] cl): Lolu ketshezi lwe-ionic luhlakaze iselula ngokuxhumana nama-hydrogen bond e-cellulose ekwamukelekayo kwe-hydrogen bond kwamukelayo.
I-1-Ethl-3-methylimidazolium acetate ([Emim]): Lolu ketshezi lwe-ionic lungancibilikisa ukugxila okuphezulu kwe-cellulose ngaphansi kwezimo ezimnene ezingejwayelekile.
2. Amine Oxidant Solution
Isixazululo se-Amine Oxidant esifana nesixazululo esixubile seDiethyyamine (DEA) neCopper Chloride ibizwa nge- [CU (II) -Amimoni solution], okuwuhlelo oluqinile lwe-solvent olungasusa iselula. Ibhubhisa ukwakheka kwe-crystal ye-cellulose nge-oxidation kanye ne-hydrogen bonding, okwenza i-cellulose i-chain chain i-softer kanye nokuncibilika okuningi.
3. I-Lithium Chloride-DimethylaceTamide (I-LICL-DMAC) System
I-ICHL-DMAC (I-Lithium Chloride-Dimethylacetamide) uhlelo kungenye yezindlela zakudala zokuqeda iselula. I-Licl ingakha umncintiswano wama-hydrogen bonds, ngaleyo ndlela ebhubhisa inethiwekhi ye-hydrogen bond phakathi kwama-molecule we-cellulose, ngenkathi i-DMAC njenge-solvent ingasebenzisana kahle ne-cellulose.
4. I-Hydrochloric acid / Zinc Chloride Solution
I-hydrochloric acid / zinc chloride solution iyi-realent yokuqala etholakele engahle ichithe iselula. It can dissolve cellulose by forming a coordination effect between zinc chloride and cellulose molecular chains, and hydrochloric acid destroying the hydrogen bonds between cellulose molecules. Kodwa-ke, lesi sixazululo silimaze kakhulu kwimishini futhi sikhawulelwe kuzinhlelo zokusebenza ezisebenzayo.
5. Ama-enbrinolytic enzymes
Ama-enbrinolytic enzymes (njengama-mourlases) ancibilikisa iselula ngo-catalyzing ukubola kwe-cellulose kube ama-oligosaccharides amancane nama-monosaccharides. Le ndlela inezicelo eziningi ezinhlobonhlobo emikhakheni ye-biodegradation kanye nokuguqulwa kwe-biomass, yize inqubo yayo yokuchithwa akuyona ukuqedwa kwamakhemikhali ngokuphelele, kepha itholakala nge-biocatalysis.
(3) Indlela yokuchithwa kwe-cellulose
Ama-reagents ahlukene anezindlela ezahlukene zokuqeda iselula, kepha ngokujwayelekile zingabangelwa izindlela ezimbili eziphambili:
Ukubhujiswa kwe-Hydrogen Bonds: Ukubhubhisa ama-hydrogen bond phakathi kwamaketanga ama-cellulose molecular ngokusebenzisa ukwakheka kwe-hydrogen bond noma ukusebenzisana kwe-ionic, okwenza kuncibilike.
Ukuphumula kwe-Molecular Chain: ukukhulisa ukuthamba kwamaketanga ama-cellulose ama-molecular kanye nokunciphisa ikristality yamaketanga amamolekyuli ngezindlela zomzimba noma zamakhemikhali, ukuze zichithwe kuma-solvents.
(4) Ukusetshenziswa okusebenzayo kokuchithwa kwe-cellulose
Ukuchithwa kwe-Cellulose kunezicelo ezibalulekile emikhakheni eminingi:
Ukulungiswa kwe-cellulose derivatives: Ngemuva kokuncibilika iselula, kungaqhutshekwa ngokwengeziwe ngamakhemikhali ukulungiselela izithambiso ze-cellulose, ama-cellulose esters nezinye izinto zokutholwa, ezisetshenziswayo kanye nezinye izinkambu.
Izinto zokwenziwa ezisekelwe ku-cellulose: Kusetshenziswa ukuncibilika kwe-cellulose, ama-cellulose nanofibers, ama-mempeliose membranes nezinye izinto zingalungiswa. Lezi zinto zokwenziwa zinezakhiwo ezinhle zemishini kanye nokuqina.
I-Biomass Energy: Ngokuncibilika kanye nokudiliza iselula, kungaguqulwa kube ngushukela ovuthayo ukuze kukhiqizwe ama-biofuels anjengeBioethanol, okusiza ukufeza ukuthuthukiswa kanye nokusetshenziswa kwamandla avuselelekayo.
Ukuchithwa kwe-Cellulose kuyinqubo eyinkimbinkimbi ehilela izindlela eziningi zamakhemikhali nezomzimba. Ama-Ionic Liquid, ama-Amino Oxidant Solutions, ama-Licl-DMAC amasistimu, i-hydrochloric acid / zinc chloride solutions kanye nama-enzymetic enzyme njengamanje ayaziwa ukuthi yi-ejenti ephumelelayo yokuqeda ama-cellulose. Umenzeli ngamunye unendlela yawo eyingqayizivele yokuchithwa kanye nensimu yesicelo. Ngokutadisha okujulile kwe-Cellulose Disolution Mechanism, kukholelwa ukuthi izindlela ezisebenza kahle futhi ezinobungane zokuqothula zizothuthukiswa, zinikeze amathuba amaningi okusetshenziswa kanye nokuthuthukiswa kwe-cellulose.
Isikhathi sePosi: Jul-09-2024