ʻO Cellulose, ka polymer organik nui loa ma ka Honua, he hapa nui o ka biomass a me nā mea ʻenehana like ʻole. ʻO kona kūpaʻa ʻano kupaianaha ka mea e hoʻohālikelike ai i kāna haki ʻana, koʻikoʻi no nā noi e like me ka hana biofuel a me ka hoʻokele ʻōpala. Ua puka mai ka hydrogen peroxide (H2O2) ma ke ʻano he moho no ka hoʻoheheʻe ʻana o ka cellulose ma muli o kona ʻano kūlohelohe a me nā waiwai oxidizing.
Hoʻolauna:
ʻO Cellulose, he polysaccharide i haku ʻia me nā ʻāpana glucose i hoʻopili ʻia e nā paʻa β-1,4-glycosidic, he mea hana nui i loko o nā paia o nā mea kanu. ʻO ka nui o ka biomass e lilo ia i kumu waiwai no nā ʻoihana like ʻole, me ka pepa a me ka pulp, textiles, a me ka bioenergy. Eia nō naʻe, ʻo ka pūnaewele hoʻopaʻa hydrogen ikaika i loko o nā fibrils cellulose e hoʻolilo iā ia i ka pale ʻana i ka hoʻoheheʻe ʻana i ka hapa nui o nā solvents, e hoʻopiʻi ana i kāna hoʻohana pono a me ka hana hou ʻana.
ʻO nā hana kuʻuna no ka hoʻoheheʻe cellulose e pili ana i nā kūlana koʻikoʻi, e like me nā waikawa concentrated a i ʻole nā wai ionic, i pili pinepine ʻia me nā hopohopo kaiapuni a me ka nui o ka ikehu. ʻO ka hoʻohālikelike ʻana, hāʻawi ka hydrogen peroxide i kahi koho hoʻohiki ma muli o kona ʻano oxidizing haʻahaʻa a me ka hiki ke hana i ka cellulose aloha. Hoʻopili kēia pepa i nā hana e hoʻoheheʻe ana i ka cellulose me ka hydrogen peroxide-mediated cellulose a loiloi i kona pono a me nā hoʻohana pono.
Mechanisms of Cellulose Dissolution by Hydrogen Peroxide:
ʻO ka hoʻoheheʻe ʻia ʻana o ka cellulose e ka hydrogen peroxide e pili ana i nā hopena kemika paʻakikī, ʻoi aku ka nui o ka hoʻokaʻawale oxidative o nā mea paʻa glycosidic a me ka hoʻopau ʻana i ka pilina hydrogen intermolecular. Hoʻomaka ke kaʻina hana ma o nā ʻanuʻu aʻe:
Oxidation of Hydroxyl Groups: Hoʻopili ka hydrogen peroxide me nā pūʻulu cellulose hydroxyl, e alakaʻi ana i ka hoʻokumu ʻana i nā radical hydroxyl (•OH) ma o Fenton a i ʻole Fenton-like reactions i mua o nā ion metala hoʻololi. Hoʻouka kēia mau radical i nā paʻa glycosidic, hoʻomaka i ka ʻoki kaulahao a hana i nā ʻāpana cellulose pōkole.
Hoʻopau i ka hoʻopaʻa ʻana o ka hydrogen: hoʻopau pū nā radical hydroxyl i ka pūnaewele hoʻopaʻa hydrogen ma waena o nā kaulahao cellulose, hoʻonāwaliwali i ka hana holoʻokoʻa a hoʻomaʻamaʻa i ka hoʻonā.
Ka hoʻokumu ʻana o nā mea hoʻoheheʻe ʻia: ʻO ka hoʻohaʻahaʻa ʻana o ka cellulose ka hopena i ka hoʻokumu ʻana i nā mea hoʻoheheʻe wai, e like me nā waikawa carboxylic, aldehydes, a me nā ketones. Hāʻawi kēia mau derivatives i ke kaʻina dissolution ma o ka hoʻonui ʻana i ka solubility a me ka hōʻemi ʻana i ka viscosity.
Depolymerization a me Fragmentation: Ke alakaʻi aku nei ka hoʻoneʻe oxidation a me ka hoʻokaʻawale ʻana i ka depolymerization o nā kaulahao cellulose i loko o nā oligomers pōkole a i ka hopena i nā sugar soluble a i ʻole nā huahana haʻahaʻa haʻahaʻa-molecular-weight.
Nā mea e pili ana i ka hoʻoheheʻe ʻia ʻana o ka hydrogen peroxide-mediated cellulose:
Hoʻopili ʻia ka maikaʻi o ka cellulose dissolution me ka hydrogen peroxide e nā kumu like ʻole, e like me:
ʻO ka hoʻopaʻa ʻana o ka hydrogen peroxide: ʻoi aku ke kiʻekiʻe o ka hydrogen peroxide i ka hopena maʻamau i ka wikiwiki o ka hopena a me ka hoʻohaʻahaʻa cellulose. Eia nō naʻe, hiki ke alakaʻi i ka ʻike kiʻekiʻe loa i nā hopena ʻaoʻao a i ʻole nā huahana makemake ʻole.
pH a me ka Mahana: ʻO ka pH o ka mea hoʻohālikelike e hoʻoikaika i ka hana o nā radical hydroxyl a me ka paʻa o nā derivatives cellulose. Manaʻo pinepine ʻia nā kūlana ʻakika haʻahaʻa (pH 3-5) e hoʻonui i ka hoʻoheheʻe cellulose me ka ʻole o ka hōʻino nui ʻana. Hoʻohui hou, pili ka mahana i nā kinetics pane, me nā mahana kiʻekiʻe e hoʻolalelale i ke kaʻina hoʻoheheʻe.
Loaʻa i nā Catalysts: Hiki i nā ion metala hoʻololi, e like me ka hao a i ʻole ke keleawe, hiki ke hoʻoheheʻe i ka decomposition o ka hydrogen peroxide a hoʻonui i ka hoʻokumu ʻana o nā radical hydroxyl. Eia nō naʻe, pono e hoʻopaʻa pono ʻia ke koho ʻana o ka catalyst a me kāna ʻano e hōʻemi i nā hopena ʻaoʻao a hōʻoia i ka maikaʻi o ka huahana.
Cellulose Morphology a me Crystallinity: ʻO ka hiki ʻana o nā kaulahao cellulose i ka hydrogen peroxide a me nā radical hydroxyl i hoʻopili ʻia e ka morphology a me ka hoʻolālā crystalline. ʻOi aku ka maʻalahi o nā ʻāina Amorphous i ka hoʻohaʻahaʻa ʻana ma mua o nā kikowaena crystalline kiʻekiʻe, pono i ka pretreatment a i ʻole nā hoʻololi hoʻololi e hoʻomaikaʻi ai i ka hiki.
ʻO nā pono a me nā hoʻohana ʻana o ka hydrogen peroxide i ka hoʻoheheʻe cellulose:
Hāʻawi ka hydrogen peroxide i nā pono no ka hoʻoheheʻe cellulose i hoʻohālikelike ʻia i nā ʻano hana maʻamau:
Ka Hoʻohālikelike Kaiapuni: ʻAʻole like me nā kemika koʻikoʻi e like me ka sulfuric acid a i ʻole nā solvents chlorinated, ʻoi aku ka maikaʻi o ka hydrogen peroxide a decomposes i loko o ka wai a me ka oxygen ma lalo o nā kūlana haʻahaʻa. ʻO kēia hiʻohiʻona pili i ke kaiapuni i kūpono ia no ka hoʻoponopono cellulose mau a me ka hoʻoponopono ʻōpala.
Nā Kūlana Māmā: Hiki ke hoʻopau ʻia ka hoʻoheheʻe ʻana o ka cellulose hydrogen peroxide-mediated ma lalo o nā kūlana haʻahaʻa o ka mahana a me ke kaomi, e hōʻemi ana i ka hoʻohana ʻana i ka ikehu a me nā kumukūʻai hana i hoʻohālikelike ʻia me ka hydrolysis acid kiʻekiʻe a i ʻole nā wai wai ionic.
ʻO ka Oxidation koho: Hiki ke hoʻomalu ʻia ka oxidative cleavage o nā paʻa glycosidic e ka hydrogen peroxide i kekahi ʻano, e ʻae ai i ka hoʻololi koho ʻana i nā kaulahao cellulose a me ka hana ʻana o nā derivatives i hoʻohālikelike ʻia me nā waiwai kikoʻī.
Nā noi nui: ʻO nā derivatives cellulose soluble i loaʻa mai ka hydrogen peroxide-mediated dissolution i hiki ke hoʻohana ʻia ma nā ʻano ʻano like ʻole, me ka hana biofuel, nā mea hana, nā mea biomedical, a me ka mālama wai ʻino.
Nā Luʻi a me nā kuhikuhi e hiki mai ana:
ʻOiai ʻo kāna mau ʻano hoʻohiki, ʻo ka hydrogen peroxide-mediated cellulose dissolution ke alo nei i nā pilikia a me nā wahi e hoʻomaikaʻi ai:
Ke koho a me ka hua ʻana: He paʻakikī ka loaʻa ʻana o nā hua kiʻekiʻe o ka cellulose soluble me nā ʻaoʻao liʻiliʻi liʻiliʻi, ʻoi aku ka paʻakikī o nā meaʻai biomass paʻakikī me ka lignin a me ka hemicellulose.
ʻO ka hoʻonui ʻana a me ka hoʻohui ʻana i ke kaʻina hana: ʻO ka hoʻonui ʻana i nā kaʻina hoʻoheheʻe cellulose ma muli o ka hydrogen peroxide i nā pae ʻoihana pono e noʻonoʻo pono i ka hoʻolālā ʻana o ka reactor, ka hoʻihoʻi ʻana i ka solvent, a me nā kaʻina hana i lalo e hōʻoia i ka holomua waiwai a me ka hoʻomau ʻana o ke kaiapuni.
Hoʻomohala Catalyst: He mea nui ka hoʻolālā ʻana o nā catalysts no ka hoʻoulu ʻana o ka hydrogen peroxide a me ka cellulose oxidation no ka hoʻonui ʻana i nā helu pane a me ke koho ʻana i ka wā e hōʻemi ana i ka hoʻouka catalyst a me ka hoʻokumu ʻana o nā huahana.
ʻO ka Valorization o By-Products: ʻO nā hoʻolālā no ka hoʻonui ʻana i nā huahana i hana ʻia i ka wā o ka hoʻoheheʻe ʻana o ka cellulose me ka hydrogen peroxide-mediated cellulose, e like me ka carboxylic acids a i ʻole ka oligomeric sugars, hiki ke hoʻonui i ka hoʻomau holoʻokoʻa a me ka hoʻokele waiwai o ke kaʻina hana.
ʻO ka hydrogen peroxide ka ʻōlelo koʻikoʻi ma ke ʻano he ʻōmaʻomaʻo a me ka versatile solvent no ka cellulose dissolution, e hāʻawi ana i nā mea maikaʻi e like me ka hoʻohālikelike ʻana i ke kaiapuni, nā ʻano hoʻohālikelike haʻahaʻa, a me ka koho koho. ʻOiai nā pilikia e hoʻomau nei, e hoʻomau ka noiʻi ʻana i ka wehewehe ʻana i nā mīkini kumu, ka hoʻonui ʻana i nā ʻāpana hopena, a me ka ʻimi ʻana i nā noi hou e hoʻonui hou i ka hiki a me ka hoʻomau ʻana o nā kaʻina hana hydrogen peroxide no ka cellulose valorization.
Ka manawa hoʻouna: Apr-10-2024