Kapangidwe ka ma demulsifier a mafuta osakonzedwa kamachokera ku mfundo yosinthira-kusintha-kusintha-kusintha. Pambuyo powonjezera demulsifier, kusintha kwa gawo kumachitika: ma surfactants omwe amatha kupanga mtundu wa emulsion wosiyana ndi womwe umapangidwa ndi emulsifier (womwe umadziwika kuti reverse-phase demulsifiers) amayamba kukhalapo. Ma demulsifier oterewa amachitapo kanthu ndi ma emulsifier a hydrophobic kuti apange ma complexes, motero amachotsa emulsifier mphamvu yake yopangira emulsifier.
Njira ina ndi kuphulika kwa filimu yolumikizana ndi nkhope chifukwa cha kugundana. Pakakhala kutentha kapena kugwedezeka, demulsifier ili ndi mwayi wokwanira wogundana ndi filimu yolumikizana ndi emulsion, mwina kuigwira kapena kusuntha ndikusintha magawo a zinthu zomwe zimagwira ntchito pamwamba, motero kuphwanya filimuyo. Izi zimachepetsa kwambiri kukhazikika, zomwe zimapangitsa kuti flicculation ndi coalescence zichitike zomwe zimapangitsa kuti demulsification ichitike.
Mafuta osaphikidwa nthawi zambiri amapezeka popanga ndi kuyeretsa zinthu zamafuta. Mafuta ambiri osaphikidwa padziko lonse lapansi amapezeka mu emulsified. Emulsion imakhala ndi zakumwa zosachepera ziwiri zosasakanikirana, chimodzi mwa izo chimamwazika bwino—madontho pafupifupi 1 μm m'mimba mwake—mkati mwa china.
Chimodzi mwa zakumwazi nthawi zambiri chimakhala madzi, china nthawi zambiri chimakhala mafuta. Mafuta amatha kufalikira bwino m'madzi kotero kuti emulsion imakhala mtundu wa mafuta-mu-madzi (O/W), pomwe madzi ndi gawo lopitilira ndipo mafuta gawo lofalikira. Mosiyana ndi zimenezi, ngati mafuta amapanga gawo lopitilira ndikuthirira gawo lofalikira, emulsion ndi mtundu wa madzi-mu-mafuta (W/O)—mafuta ambiri osakonzedwa ali m'gulu lomalizali.
Mamolekyu amadzi amakokana, monganso mamolekyu amafuta; komabe pakati pa madzi ndi mamolekyu amafuta pamakhala mphamvu yonyansa yomwe imagwira ntchito pamalo awo. Kukanika kwa pamwamba kumachepetsa malo olumikizirana, kotero madontho mu emulsion ya W/O amafikira ku sphericity. Kuphatikiza apo, madontho amodzi amasankha kusonkhana, komwe malo ake onse ndi ochepa kuposa kuchuluka kwa malo osiyana a madontho. Chifukwa chake, emulsion ya madzi oyera ndi mafuta oyera ndi yosakhazikika: gawo lomwazikana limakokedwa ku coalescence, ndikupanga zigawo ziwiri zolekanitsidwa akangotha kukana kwa interfacial - mwachitsanzo, mwa kusonkhanitsa mankhwala apadera pamalo olumikizirana, zomwe zimachepetsa kukangana kwa pamwamba. Mwaukadaulo, ntchito zambiri zimagwiritsa ntchito izi powonjezera ma emulsifier odziwika bwino kuti apange ma emulsion okhazikika. Chinthu chilichonse chokhazikika mu emulsion mwanjira iyi chiyenera kukhala ndi kapangidwe ka mankhwala komwe kamalola kuyanjana nthawi imodzi ndi mamolekyu amadzi ndi mafuta - kutanthauza kuti, chiyenera kukhala ndi gulu lokonda madzi ndi gulu lokonda madzi.
Ma emulsion amafuta osakonzedwa bwino amachokera ku zinthu zachilengedwe zomwe zili mu mafuta, nthawi zambiri zimakhala ndi magulu a polar monga carboxyl kapena phenolic. Izi zitha kukhalapo ngati mayankho kapena colloidal dispersions, zomwe zimakhudza kwambiri zikalumikizidwa ku ma interface. M'mikhalidwe yotere, tinthu tambiri timafalikira mu gawo la mafuta ndikusonkhanitsa pamalo olumikizirana mafuta ndi madzi, ndikulumikizana ndi magulu awo a polar omwe akuyang'ana madzi. Gawo lokhazikika la interfacial limapangidwa, lofanana ndi chigoba cholimba chofanana ndi tinthu tating'onoting'ono kapena paraffin crystal lattice. Kwa maso, izi zimawonekera ngati chophimba chomwe chimaphimba gawo lolumikizira. Njirayi imafotokoza kukalamba kwa ma emulsion amafuta osakonzedwa bwino komanso kuvutika kuwaswa.
M'zaka zaposachedwapa, kafukufuku wokhudza njira zochotsera mafuta osakonzedwa bwino wakhala akuyang'ana kwambiri pa kafukufuku wozama wa njira zolumikizirana kwa madontho a madzi ndi momwe ma demulsifiers amakhudzira mphamvu za rheological za interfacial. Komabe chifukwa chakuti zochita za ma demulsifiers pa ma emulsions n'zovuta kwambiri, ndipo ngakhale kuti pali maphunziro ambiri m'munda uno, palibe chiphunzitso chogwirizana cha njira yochotsera mafuta chomwe chapezeka.
Njira zingapo zikudziwika pakali pano:
③ Njira Yosungunula– Molekyulu imodzi kapena mamolekyu angapo a demulsifier amatha kupanga micelles; ma macromolecular coils kapena micelles awa amasungunula mamolekyu a emulsifier, zomwe zimapangitsa kuti mafuta osakonzedwa a emulsified asweke.
④ Njira yopindika-yosinthika– Kuwona kwa microscopic kukuwonetsa kuti ma emulsion a W/O ali ndi zipolopolo zamadzi ziwiri kapena zingapo, ndipo zipolopolo zamafuta zimayikidwa pakati pawo. Pogwiritsa ntchito mphamvu yotenthetsera, kusakaniza, ndi demulsifier, zigawo zamkati za madontho zimalumikizana, zomwe zimapangitsa kuti madontho azigwirizana komanso kuti madontho azisungunuka.
Kuphatikiza apo, kafukufuku wa m'dziko muno pa njira zochotsera mafuta osakonzedwa ndi O/W akusonyeza kuti chochotsera mafuta chosakonzedwa bwino chiyenera kukwaniritsa izi: kugwira ntchito bwino pamwamba; kugwira ntchito bwino konyowa; mphamvu yokwanira yolumikizira madzi; komanso kuthekera kogwirizanitsa bwino mafuta.
Ma demulsifiers amabwera m'mitundu yosiyanasiyana; amagawidwa m'magulu malinga ndi mitundu ya surfactant, kuphatikizapo mitundu ya cationic, anionic, nonionic, ndi zwitterionic.
Zochotsa mphamvu za anionic: ma carboxylates, ma sulfonates, ma polyoxyethylene fatty acid sulfate esters, ndi zina zotero.—zoyipa zake ndi monga kuchuluka kwa mlingo, kusagwira bwino ntchito, komanso kusagwira bwino ntchito ngati pali ma electrolytes.
Ma demulsifier a cationic: makamaka mchere wa ammonium wa quaternary—wothandiza pa mafuta opepuka koma wosayenera pa mafuta olemera kapena akale.
Ma demulsifiers osakhala a ionic: ma block copolymers oyambitsidwa ndi amines; ma block copolymers oyambitsidwa ndi alcohols; alkylphenol-formaldehyde resin block copolymers; phenol-amine-formaldehyde resin block copolymers; ma demulsifiers opangidwa ndi silicone; ma ultra-high molecular weight demulsifiers; ma polyphosphates; ma modified block copolymers; ndi ma zwitterionic demulsifiers oimiridwa ndi ma imidazoline-based crude oil demulsifiers.
Nthawi yotumizira: Dec-04-2025