ʻO ka cellulose kahi polysaccharide paʻakikī i haku ʻia me nā ʻāpana glucose he nui i hoʻopili ʻia e nā paʻa β-1,4-glycosidic. ʻO ia ka mea nui o nā paia o nā mea kanu a hāʻawi i nā paia o nā mea kanu i ke kākoʻo a me ka paʻakikī. Ma muli o ke kaulahao molekula cellulose lōʻihi a me ka crystallinity kiʻekiʻe, he paʻa ikaika a me ka insolubleness.
(1) Nā waiwai o ka cellulose a me ka paʻakikī i ka hoʻoheheʻe ʻana
Loaʻa iā Cellulose nā waiwai i hiki ke hoʻoheheʻe ʻia:
Kiʻekiʻe crystallinity: Hoʻokumu ʻia nā kaulahao molekula cellulose i kahi ʻano lattice paʻa ma o nā paʻa hydrogen a me nā ikaika van der Waals.
Kiʻekiʻe kiʻekiʻe o ka polymerization: He kiʻekiʻe ke degere o ka polymerization (ʻo ia hoʻi ka lōʻihi o ke kaulahao mole) o cellulose, maʻamau mai nā haneli a hiki i nā tausani o nā ʻāpana glucose, e hoʻonui ai i ka paʻa o ka mole.
Pūnaehana paʻa hydrogen: Aia nā paʻa hydrogen ma waena a i loko o nā kaulahao molekula cellulose, e paʻakikī ai ka luku ʻia a hoʻoheheʻe ʻia e nā mea hoʻoheheʻe maʻamau.
(2) Nā mea hoʻonā e hoʻoheheʻe i ka cellulose
I kēia manawa, ʻo nā reagents i ʻike ʻia e hiki ke hoʻopau maikaʻi i ka cellulose e komo pū me kēia mau ʻano:
1. Nā wai ionic
ʻO nā wai Ionic nā wai i haku ʻia me nā cation organik a me nā anion organik a i ʻole nā anion, maʻamau me ka haʻahaʻa haʻahaʻa, ke kūpaʻa wela kiʻekiʻe a me ka hoʻoponopono kiʻekiʻe. Hiki i kekahi mau wai ionic ke hoʻoheheʻe i ka cellulose, a ʻo ka hana nui ke wāwahi i nā paʻa hydrogen ma waena o nā kaulahao mole cellulose. ʻO nā wai ionic maʻamau e hoʻopau i ka cellulose penei:
1-Butyl-3-methylimidazolium chloride ([BMIM]Cl): Hoʻoheheʻe kēia wai ionic i ka cellulose ma o ka launa pū ʻana me nā paʻa hydrogen i cellulose ma o nā mea hoʻopaʻa hydrogen.
1-Ethyl-3-methylimidazolium acetate ([EMIM][Ac]): Hiki i kēia wai ionic ke hoʻoheheʻe i nā kiʻekiʻe o ka cellulose ma lalo o nā kūlana haʻahaʻa.
2. ʻAmina oxidant solution
ʻO ka solution oxidant Amine e like me ka hopena hui o diethylamine (DEA) a me ka copper chloride ua kapa ʻia ʻo [Cu(II) -ammonium solution], he ʻōnaehana hoʻoheheʻe ikaika e hiki ke hoʻopau i ka cellulose. Hoʻopau ia i ke ʻano aniani o ka cellulose ma o ka oxidation a me ka hoʻopaʻa ʻana i ka hydrogen, e ʻoi aku ka palupalu o ke kaulahao molekula cellulose.
3. Pūnaehana Lithium chloride-dimethylacetamide (LiCl-DMAc).
ʻO ka ʻōnaehana LiCl-DMAc (lithium chloride-dimethylacetamide) kekahi o nā ala maʻamau no ka hoʻopau ʻana i ka cellulose. Hiki i ka LiCl ke hoʻokūkū i nā paʻa hydrogen, a laila e hoʻopau ai i ka ʻoihana paʻa hydrogen ma waena o nā molekole cellulose, ʻoiai ʻo DMAc ma ke ʻano he solvent hiki ke launa maikaʻi me ke kaulahao mole cellulose.
4. ʻO ka waiʻona hydrochloric/zinc chloride solution
ʻO ka ʻakika hydrochloric/zinc chloride solution kahi reagent i ʻike mua ʻia e hiki ke hoʻopau i ka cellulose. Hiki iā ia ke hoʻoheheʻe i ka cellulose ma ka hana ʻana i ka hopena hoʻohui ma waena o ka zinc chloride a me nā kaulahao molekula cellulose, a me ka waika hydrochloric e luku ana i nā paʻa hydrogen ma waena o nā molekole cellulose. Eia nō naʻe, ʻoi loa ka corrosive o kēia hopena i nā mea hana a ua kaupalena ʻia i nā noi hana.
5. Nā enzymes fibrinolytic
Hoʻoheheʻe nā enzyme Fibrinolytic (e like me nā cellulases) i ka cellulose ma o ka hoʻopili ʻana i ka decomposition o cellulose i loko o nā oligosaccharides a me nā monosaccharides liʻiliʻi. Loaʻa i kēia ʻano hana ka nui o nā noi ma nā kahua o ka biodegradation a me ka hoʻololi ʻana o ka biomass, ʻoiai ʻo kāna kaʻina dissolution ʻaʻole ia he hoʻoheheʻe kemika holoʻokoʻa, akā loaʻa ma o ka biocatalysis.
(3) Mechanism of cellulose dissolution
Loaʻa nā ʻano hana like ʻole o nā reagents no ka hoʻopau ʻana i ka cellulose, akā ma ke ʻano maʻamau, hiki ke hoʻohālikelike ʻia i ʻelua mau hana nui:
Hoʻopau i nā paʻa hydrogen: Ke luku nei i nā paʻa hydrogen ma waena o nā kaulahao molekula cellulose ma o ka hoʻokūkū hoʻokūkū hydrogen a i ʻole ka pilina ionic, e hoʻoheheʻe ʻia.
ʻO ka hoʻomaha hoʻomaha molecular: Hoʻonui i ka palupalu o nā kaulahao mole cellulose a hoʻemi i ka crystallinity o nā kaulahao mole ma o ke ʻano kino a i ʻole kemika, i hiki ke hoʻoheheʻe ʻia i nā solvents.
(4) Nā noi kūpono o ka hoʻoheheʻe cellulose
He mau noi koʻikoʻi ka dissolution cellulose ma nā ʻano he nui:
Ka hoʻomākaukau ʻana i nā derivatives cellulose: Ma hope o ka hoʻoheheʻe ʻana i ka cellulose, hiki ke hoʻololi hou ʻia e hoʻomākaukau i nā cellulose ethers, cellulose esters a me nā mea ʻē aʻe, i hoʻohana nui ʻia i ka meaʻai, ka lāʻau lapaʻau, ka uhi a me nā māla ʻē aʻe.
Nā mea pili i ka cellulose: Hiki ke hoʻomākaukau i ka cellulose dissolved, cellulose nanofibers, cellulose membranes a me nā mea ʻē aʻe. Loaʻa i kēia mau mea nā waiwai mechanical maikaʻi a me ka biocompatibility.
ʻO ka ikehu biomass: Ma ka hoʻoheheʻe ʻana a me ka hoʻohaʻahaʻa ʻana i ka cellulose, hiki ke hoʻololi ʻia i sugars fermentable no ka hana ʻana i nā biofuels e like me ka bioethanol, e kōkua ana e hoʻokō i ka hoʻomohala ʻana a me ka hoʻohana ʻana i ka ikehu hou.
ʻO ka hoʻoheheʻe ʻana o ka cellulose he kaʻina hana paʻakikī e pili ana i nā hana kemika a me ke kino. ʻO nā wai Ionic, nā hāʻina amino oxidant, nā ʻōnaehana LiCl-DMAc, hydrochloric acid / zinc chloride solutions a me nā enzyme cellolytic i kēia manawa i ʻike ʻia he mau mea hana kūpono no ka hoʻopau ʻana i ka cellulose. Loaʻa i kēlā me kēia ʻelele kona ʻano hoʻoheheʻe kūʻokoʻa a me ke kahua noi. Me ka noiʻi hohonu o ka mīkini hoʻoheheʻe cellulose, manaʻoʻiʻo ʻia e hoʻomohala ʻia nā ʻano hana hoʻoheheʻe ʻoi aku ka maikaʻi a me ke kaiapuni, e hāʻawi ana i nā mea hou aku no ka hoʻohana ʻana a me ka hoʻomohala ʻana i ka cellulose.
Ka manawa hoʻouna: Jul-09-2024