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IZINDLELA ZOKUKHIPHA I-ALKYL GLUCOSIDE

I-Fischer glycosidation iyona ndlela kuphela yokuhlanganiswa kwamakhemikhali eye yasiza ukuthuthukiswa kwezixazululo zanamuhla zomnotho nezobuchwepheshe zokukhiqiza ngezinga elikhulu ama-alkyl polyglucosides.Izitshalo zokukhiqiza ezinamandla angaphezu kuka-20,000 t/ngonyaka sezivele zenziwe futhi zandisa uhla lwemikhiqizo yemboni ye-surfactants ngama-ejenti asebenza phezulu asekelwe ezintweni ezingavuthiwe ezivuselelekayo.I-D-Glucose kanye ne-linear C8-C16 fatty alcohols kubonakale kuyizo zokudla ezithandwayo.Lawa ma-educts angaguqulwa abe ama-alkyl polyglucosides asebenza phezulu ngokusebenzisa i-Fischer glycosidation eqondile noma i-transglycosidation yezinyathelo ezimbili nge-butyl polyglucoside lapho kukhona izisusa ze-asidi, ngamanzi njengomkhiqizo ovelayo.Amanzi kufanele acwecwe engxubeni yokusabela ukuze kugudluzwe ukulingana kokusabela kumikhiqizo oyifunayo.Ngesikhathi senqubo ye-glycosidation, ama-inhomogeneities engxubeni yokusabela kufanele agwenywe, ngoba aholela ekwakhiweni ngokweqile kwalokho okubizwa ngokuthi ama-polyglucosides, angathandeki kakhulu.Ngakho-ke amaqhinga amaningi obuchwepheshe agxila ekuhlanganiseni ama-educts i-n-glucose nama-alcohol, okungahlangani kahle ngenxa yomehluko wawo ekuhlukaniseni.Ngesikhathi sokusabela, amabhondi e-glycosidic akheka kokubili phakathi kotshwala obunamafutha kanye ne-n-glucose naphakathi kwamayunithi we-n-glucose ngokwawo.Ama-alkyl polyglucosides ngenxa yalokho akha njengengxube yamafrakshini anezinombolo ezihlukene zamayunithi e-glucose endaweni eyinsalela ye-alkyl yochungechunge olude.Ngayinye yalezi zingxenyana, yona, yakhiwa izingxenye ezimbalwa ze-isomeri, njengoba amayunithi e-n-glucose ethatha amafomu ahlukene e-anomeric kanye namafomu endandatho ekulinganisweni kwamakhemikhali ngesikhathi se-Fischer glycosidation kanye nokuxhumana kwe-glycosidic phakathi kwamayunithi e-D-glucose kwenzeka ezikhundleni ezimbalwa zokuhlangana okungenzeka. .Isilinganiso se-anomer samayunithi we-D-glucose sicishe sibe ngu-α/β= 2: 1 futhi sibonakala sinzima ukuthonywa ngaphansi kwezimo ezichaziwe ze-Fischer synthesis.Ngaphansi kwezimo ezilawulwa nge-thermodynamically, amayunithi e-n-glucose aqukethwe kungxube yomkhiqizo atholakala kakhulu ngendlela yama-pyranosides.Isilinganiso senani lamayunithi e-n-glucose ngensalela ye-alkyl, okuthiwa yi-degree of polymerization, empeleni kuwumsebenzi we-molar ratio ye-educts ngesikhathi sokukhiqizwa.Ngenxa yokuphinyiswa kwe-surfactant efanele[1], okukhethekile kunikezwa ama-alkyl polyglucosides anamadigri e-polymerization phakathi koku-1 no-3, okumele kusetshenziswe cishe u-3-10 mol onamafutha otshwala okufanele kusetshenziswe imvukuzane ngayinye ye-n-glucose ngesikhathi kuqhubeka inqubo.

Izinga le-polymerization liyehla njengoba utshwala obunamafutha amaningi bukhula.Ama-alcohol anamafutha amaningi ahlukaniswa futhi alulame ngenqubo ye-multi-step vacuum distillation ene-evaporator yefilimu ewayo, ukuze ukucindezeleka okushisayo kugcinwe kuncane.Izinga lokushisa lokuhwamuka kufanele libe phezulu ngokwanele kanye nesikhathi sokuthintana endaweni eshisayo sibe side ngokwanele ukuze kuqinisekiswe ukugcwaliswa okwanele kotshwala obunamafutha amaningi kanye nokugeleza kwe-alkyl polyglucoside kuncibilika ngaphandle kokusabela okuphawulekayo kokubola.Uchungechunge lwezinyathelo zokuhwamuka lungasetshenziswa ngokunenzuzo ukuhlukanisa kuqala ingxenyana ebilisa kancane, bese kuba inani elikhulu lotshwala obunamafutha, futhi ekugcineni notshwala obunamafutha obusele, kuze kube yilapho i-alkyl polyglycoside incibilika njengensalela encibilika emanzini.

Ngisho nangaphansi kwezimo ezithambile zokwenziwa kanye nokuhwamuka kotshwala obunamafutha, kuzovela ukuguquguquka kombala onsundu okungafuneki, futhi izinqubo zokufiphala ziyadingeka ukuze kucwengisiswe umkhiqizo.Enye indlela yokuhlanza ebonakale ifanelekile ukufaka i-oxidizing agent, njenge-hydrogen peroxide, ekwakhekeni kwamanzi kwe-alkyl polyglycoside endaweni ene-alkaline lapho kukhona ama-ion e-magnesium.

Izifundo eziningi nezinhlobonhlobo ezisetshenziswa ekuhlanganiseni, ekucubunguleni nasekucwengisweni kwenqubo ziqinisekisa ukuthi nanamuhla, akukabi bikho ikhambi le-"turnkey" elisebenza kabanzi ukuze kutholwe izinga elithile lomkhiqizo.Ngokuphambene nalokho, zonke izinyathelo zenqubo zidinga ukwakhiwa.I-Dongfu inikeza iziphakamiso ezithile zokuklama isixazululo nezixazululo zobuchwepheshe, futhi ichaza izimo zamakhemikhali nezomzimba zokusabela, ukuhlukanisa kanye nenqubo yokucwenga.

Zontathu izinqubo eziyinhloko - i-homogeneous transglycosidation, inqubo ye-slurry, kanye nendlela yokuphakela ushukela-ingasetshenziswa ngaphansi kwezimo zezimboni.Ngesikhathi se-transglycosidation, ukugcwala kwe-polyglucoside ye-butyl ephakathi, esebenza njenge-solubilizer ye-D-glucose ne-butanol educts, kufanele igcinwe ngaphezu kuka-15% engxubeni yokusabela ukuze kugwenywe i-inhomogeneities.Ngenhloso efanayo, ukugcwala kwamanzi engxubeni yokusabela esetshenziselwa ukuhlanganiswa okuqondile kwe-Fischer ye-alkyl polyglucosides kufanele kugcinwe ngaphansi kuka-1%.Emanzini aphakeme kunengozi yokuguqula i-crystalline D-glucose emisiwe ibe yisisindo esinzima, okungase kamuva kuphumele ekucutshungulweni okubi kanye nokwenza i-polymerization ngokweqile.Ukunyakazisa okusebenzayo kanye ne-homogenization kukhuthaza ukusatshalaliswa okuhle nokusebenza kabusha kwe-crystalline D-glucose kungxube yokusabela.

Kokubili izici zobuchwepheshe nezomnotho kufanele zicatshangelwe lapho kukhethwa indlela yokuhlanganisa kanye nezinhlobonhlobo zayo eziyinkimbinkimbi.Izinqubo ze-Homogeneous transglycosidation ezisekelwe ku-D-glucose syrups zibonakala zilungele ukukhiqizwa okuqhubekayo ngezinga elikhulu.Bavumela ukonga unomphela ekukhanyeni kwekristalu kwe-D-glucose eluhlaza ochungechungeni lwevelu-added, olunxephezela ngaphezu kokutshalwa kwezimali okuphezulu kwesikhathi esisodwa esinyathelweni se-transglycosidation kanye nokutholwa kwe-butanol.Ukusetshenziswa kwe-n-butanol akuvezi okunye ukonakala, njengoba ingaphinda igaywe kabusha cishe ngokuphelele ukuze ukugxilisa okusele emikhiqizweni yokugcina etholiwe kube izingxenye ezimbalwa kuphela esigidini ngasinye, okungabhekwa njengokungagxeki.I-Direct Fischer glycosidation ngokwenqubo ye-slurry noma indlela yokuphakela ushukela ikhipha isinyathelo se-transglycosidation kanye nokutholwa kwe-butanol.Kungenziwa futhi ngokuqhubekayo futhi kubiza izindleko eziphansi kancane.

Ngokuzayo, ukuhlinzekwa kanye nentengo yezinto ezisetshenziswayo nezingavuselelwa kabusha, kanye nenqubekelaphambili eyengeziwe yezobuchwepheshe ekukhiqizeni i-alkyl polysaccharides, kuzoba nomthelela omkhulu kumthamo wemakethe namandla okukhiqiza okuthuthukiswa nokusetshenziswa.I-Base polysaccharide isivele inezixazululo zayo zobuchwepheshe ezingahlinzeka ngezinzuzo ezibalulekile zokuncintisana emakethe yokwelapha engaphezulu ezinkampanini ezithuthukisa noma ezithathe izinqubo ezinjalo.Lokhu kuyiqiniso ikakhulukazi uma amanani entengo ephezulu futhi ephansi.Izindleko zokukhiqiza ze-ejenti yokukhiqiza zikhuphukele ezingeni elivamile, ngisho noma intengo yezinto zokusetshenziswa zasendaweni yehla kancane, ingase ilungise ezinye izinto ezisetshenziswayo futhi ingase ikhuthaze ukufakwa kwezitshalo ezintsha zokukhiqiza i-alkyl polysaccharide.

 


Isikhathi sokuthumela: Jul-23-2021