Cellulose, iyo yakanyanya kuwanda organic polymer paPasi, inoumba chikamu chakakosha chebiomass uye akasiyana maindasitiri zvinhu. Kurongeka kwayo kunoshamisa kunoisa matambudziko pakuparara kwayo, kwakakosha kumashandisirwo akadai sekugadzirwa kwebiofuel uye kutonga kwemarara. Hydrogen peroxide (H2O2) yabuda semumiriri anogona kunyungudutswa cellulose nekuda kwehunhu hwayo husina kunaka uye oxidizing.
Nhanganyaya:
Cellulose, polysaccharide inoumbwa neglucose units yakabatanidzwa ne β-1,4-glycosidic bonds, inhengo huru yehutano mumadziro emasero emiti. Kuwanda kwayo mubiomass kunoita kuti ive inoyevedza sosi kune akasiyana maindasitiri, anosanganisira mapepa uye pulp, machira, uye bioenergy. Nekudaro, iyo yakasimba hydrogen bonding network mukati me cellulose fibrils inoita kuti isagone kunyungudika mune zvakawanda zvinonyungudutsa, zvichiunza matambudziko pakushandisa kwayo nemazvo uye kudzokorodza zvakare.
Nzira dzechinyakare dzekuparara kwe cellulose dzinosanganisira mamiriro ezvinhu akaomarara, senge concentrated acids kana ionic zvinwiwa, izvo zvinowanzobatanidzwa nekunetseka kwezvakatipoteredza uye kushandiswa kwakanyanya kwesimba. Mukupesana, hydrogen peroxide inopa inovimbisa imwe nzira nekuda kwekunyorova kwayo oxidizing chimiro uye mukana wezvakatipoteredza zvine hushamwari cellulose kugadzirisa. Iri bepa rinoongorora maitiro ari pasi pehydrogen peroxide-mediated cellulose dissolution uye inoongorora kushanda kwayo uye kushanda kwayo.
Nzira dzekubvisa Cellulose neHydrogen Peroxide:
Kunyungudutswa kweselulosi nehydrogen peroxide kunosanganisira maitiro akaomarara emakemikari, kunyanya oxidative cleavage yeglycosidic bonds uye kukanganisa kweintermolecular hydrogen bonding. Iyo nzira inowanzoitika kuburikidza nematanho anotevera:
Oxidation yeHydroxyl Groups: Hydrogen peroxide inopindirana ne cellulose hydroxyl mapoka, zvichiita kuti pave nekugadzirwa kwehydroxyl radicals (• OH) kuburikidza neFenton kana Fenton-kufanana nekuita pamberi pekuchinja kwesimbi ions. Aya ma radicals anorwisa glycosidic bond, achitanga cheni scission uye achigadzira mapfupi cellulose zvidimbu.
Kuvhiringidzwa kweHydrogen Bonding: Hydroxyl radicals zvakare inokanganisa iyo hydrogen bonding network pakati pecheni dze cellulose, ichinetesa chimiro chese uye kufambisa kugadzirisa.
Kuumbwa kweSoluble Derivatives: Iyo oxidative degradation ye cellulose inoguma mukuumbwa kwemvura-inonyungudika yepakati, senge carboxylic acids, aldehydes, uye ketone. Izvi zvinobva kune zvinopa mukugadzirisa kwekugadzirisa nekuwedzera kunyungudika uye kuderedza viscosity.
Depolymerization uye Fragmentation: Kuwedzera oxidation uye cleavage reactions inotungamira muku depolymerization yemacheni e cellulose kuita mapfupi oligomers uye pakupedzisira kune inonyungudika shuga kana zvimwe zvakaderera-mamorekuru-huremu zvigadzirwa.
Zvinhu Zvinokanganisa Hydrogen Peroxide-Mediated Cellulose Dissolution:
Kushanda kwekuparara kweselulosi uchishandisa hydrogen peroxide kunokonzerwa nezvinhu zvakasiyana, zvinosanganisira:
Kuiswa kweHydrogen Peroxide: Kukwirira kwakanyanya kwehydrogen peroxide kazhinji kunokonzeresa kukurumidza kuita maitiro uye kuwanda kwakanyanya kweselulosi. Nekudaro, kuwandisa kwakanyanya kunogona kutungamira kune maitiro epadivi kana zvisingadiwe ne-zvigadzirwa.
pH uye Tembiricha: Iyo pH yemaitiro epakati inopesvedzera chizvarwa che hydroxyl radicals uye kugadzikana kwe cellulose derivatives. Pakati nepakati acidic mamiriro (pH 3-5) anowanzo kufarirwa kuwedzera cellulose kunyungudika pasina kuderera kwakanyanya. Pamusoro pezvo, tembiricha inokanganisa reaction kinetics, ine tembiricha yepamusoro inowanzo mhanyisa nzira yekunyungudika.
Kuvapo kweCatalysts: Shanduko yesimbi ions, senge iron kana mhangura, inogona kukonzeresa kuparara kwehydrogen peroxide uye kuwedzera kuumbwa kwehydroxyl radicals. Nekudaro, iyo sarudzo yecatalyst uye kusungirirwa kwayo kunofanirwa kunyatsogadziriswa kudzikisa maitiro epadivi uye kuve nechokwadi chemhando yechigadzirwa.
Cellulose Morphology uye Crystallinity: Kuwanikwa kwecheni dze cellulose kune hydrogen peroxide uye hydroxyl radicals kunokonzerwa neiyo morphology uye crystalline chimiro. Matunhu eAmorphous anotapukirwa zvakanyanya nekudzikira pane akanyanya crystalline domains, izvo zvinoda pretreatment kana gadziridzo nzira dzekuvandudza kuwanikwa.
Zvakanakira uye Mashandisirwo eHydrogen Peroxide muSelulosi Dissolution:
Hydrogen peroxide inopa akawanda mabhenefiti ekunyungudutswa kweselulosi kana ichienzaniswa neyakajairwa nzira:
Kugarisana Kwezvakatipoteredza: Kusiyana nemakemikari ane hutsinye akadai sesulfuric acid kana chlorinated solvents, hydrogen peroxide haina kunaka uye inoora ikava mvura uye okisijeni pasi pemamiriro akapfava. Hunhu uhwu hune hushamwari hwezvakatipoteredza hunoita kuti ive yakakodzera kugadzirwa kweselulosi uye kugadzirisa tsvina.
Mamiriro Ekuita Akapfava: Hydrogen peroxide-mediated cellulose dissolution inogona kuitwa pasi pemamiriro akapfava etembiricha uye kumanikidzwa, kuderedza kushandiswa kwesimba uye mutengo wekushandisa uchienzaniswa nepamusoro-tembiricha acid hydrolysis kana ionic mvura yekurapa.
Selective Oxidation: Iyo oxidative cleavage yeglycosidic bonds nehydrogen peroxide inogona kudzorwa kune imwe nhanho, ichibvumira kusarudzwa kuchinjwa kwemaketani e cellulose uye kugadzirwa kwezvakagadzirwa zvakagadzirirwa zvine chaiwo zvimiro.
Zvishandiso Zvakasiyana-siyana: Izvo zvinonyunguduka zveselulosi zvakatorwa kubva kuhydrogen peroxide-mediated dissolution zvine zvinogona kushandiswa munzvimbo dzakasiyana siyana, kusanganisira kugadzirwa kwebiofuel, zvinoshanda, biomedical zvishandiso, uye marara emvura.
Matambudziko uye Mafambiro Amangwana:
Pasinei nehunhu hwayo hunovimbisa, hydrogen peroxide-mediated cellulose dissolution inotarisana nematambudziko akati wandei uye nzvimbo dzekuvandudza:
Kusarudzika uye Goho: Kuwana goho rakawanda rezvinonyungudika selulosi zvinobva kune kushoma kwepadivi maitiro kunoramba kuri dambudziko, kunyanya kune yakaoma biomass feedstocks ine lignin uye hemicellulose.
Scale-Up uye Maitiro Kubatanidzwa: Kukwidza hydrogen peroxide-based cellulose dissolution maitiro kune maindasitiri mazinga kunoda kunyatsotariswa kweiyo reactor dhizaini, kudzoreredza kudzoreredza, uye kudzika nhanho yekugadzirisa kuve nechokwadi chekubudirira kwehupfumi uye kuchengetedzwa kwezvakatipoteredza.
Catalyst Development: Dhizaini yezvinoita zvinokonzeresa yehydrogen peroxide activation uye cellulose oxidation yakakosha mukusimudzira maitiro ekuita uye kusarudzwa uku uchideredza catalyst kurodha uye ne-chigadzirwa kuumbwa.
Valorization yeZvigadzirwa-Zvigadzirwa: Matanho ekusimbisa zvigadzirwa zvinogadzirwa panguva yehydrogen peroxide-mediated cellulose dissolution, senge carboxylic acids kana oligomeric shuga, inogona kuwedzera kusimudzira kwese uye hupfumi hwekuita.
Hydrogen peroxide inobata vimbiso yakakosha seyakasvibira uye inoshanda zvakasiyana-siyana yekunyungudutsa cellulose, ichipa zvakanakira sekuenderana kwezvakatipoteredza, mild reaction mamiriro, uye yakasarudzika oxidation. Kunyangwe zvimhingamipinyi zvirikuitika, kuenderera mberi nekuedza kutsvagisa kwakanangana nekujekesa nzira dziripo, kugadzirisa maitiro ekuita, uye kuongorora mashandisirwo matsva kuchawedzera kugona uye kusimba kwehydrogen peroxide-based process ye cellulose valorization.
Nguva yekutumira: Kubvumbi-10-2024