Hydroxyethyl Cellulose (HEC) ne na kowa ruwa-mai narkewa polymer yadu amfani da kullum sunadarai, gini, coatings, magani, abinci da sauran masana'antu. Ita ce ether ɗin cellulose maras ionic wanda aka yi ta hanyar sinadari mai gyara cellulose na halitta. The masana'antu tsari na hydroxyethyl cellulose ya ƙunshi hadaddun sinadaran halayen, ciki har da cellulose hakar, alkalisation jiyya, etherification dauki, da dai sauransu Wadannan ne cikakken gabatarwar ta masana'antu tsari.
1. Zaɓin albarkatun ƙasa da hakar cellulose
Asalin albarkatun kasa na hydroxyethyl cellulose shine cellulose na halitta, wanda yafi fitowa daga itace, auduga ko wasu filaye na shuka. Abubuwan da ke cikin cellulose a cikin ganuwar tantanin halitta yana da girma, kuma ana iya fitar da cellulose mai tsabta daga waɗannan kayan halitta ta hanyar inji ko sinadarai. Tsarin hakar ya haɗa da murkushewa, kawar da ƙazanta (kamar lignin, hemicellulose), bleaching da sauran matakai.
Hakar Cellulose: Halittar cellulose galibi ana yin amfani da injina ko sinadarai don cire abubuwan da ba cellulose ba don samun cellulose mai tsafta. Fiber na auduga, ɓangaren litattafan almara, da dai sauransu na iya zama tushen albarkatun ƙasa na gama gari. A lokacin aikin jiyya, ana amfani da alkali (kamar sodium hydroxide) don taimakawa wajen narkar da abubuwan da ba na cellulose ba, sauran kuma galibi cellulose ne.
2. Maganin Alkali
Tabbataccen cellulose dole ne a fara alkalized. Wannan mataki shine don sa ƙungiyoyin hydroxyl akan sarkar kwayoyin halitta ta cellulose suyi aiki don su iya amsawa cikin sauƙi tare da wakili na etherifying. Babban matakan maganin alkalisation sune kamar haka:
Reaction na cellulose tare da alkali: cellulose yana hade da karfi alkali (yawanci sodium hydroxide) don samar da alkali cellulose (Alkali Cellulose). Yawancin lokaci ana aiwatar da wannan tsari a cikin ruwa mai ruwa. Alkali cellulose shine samfurin amsawar cellulose da sodium hydroxide. Wannan abu yana da tsarin sako-sako da kuma mafi girma reactivity, wanda ya dace da halayen etherification na gaba.
Tsarin alkalization yafi faruwa a yanayin zafi da zafi mai dacewa, yawanci a cikin kewayon 20 ℃ ~ 30 ℃ na sa'o'i da yawa don tabbatar da cewa ƙungiyoyin hydroxyl a cikin ƙwayoyin cellulose suna aiki sosai.
3. Etherification dauki
Etherification shine muhimmin mataki a cikin samar da hydroxyethyl cellulose. Ana samar da hydroxyethyl cellulose ta hanyar amsa alkali cellulose tare da ethylene oxide don gabatar da ƙungiyoyin hydroxyethyl. Takamaiman matakan sune kamar haka:
Halin da ethylene oxide: Alkali cellulose yana amsawa tare da wani adadin ethylene oxide a ƙarƙashin wasu yanayin zafi da matsa lamba. Tsarin zobe a cikin ethylene oxide yana buɗewa don samar da haɗin ether, yana amsawa tare da ƙungiyoyin hydroxyl a cikin ƙwayoyin cellulose, kuma yana gabatar da ƙungiyoyin hydroxyethyl (-CH2CH2OH). Wannan tsari na iya daidaita matakin etherification ta hanyar sarrafa yanayin halayen (kamar zazzabi, matsa lamba, da lokaci).
Yawancin lokaci ana aiwatar da halayen a cikin yanayin alkaline don tabbatar da ingancin etherification. A dauki zazzabi ne kullum 50 ℃ ~ 100 ℃, da dauki lokaci ne da yawa hours. Ta hanyar daidaita adadin ethylene oxide, ana iya sarrafa matakin maye gurbin samfurin ƙarshe, wato, yawancin ƙungiyoyin hydroxyl a cikin ƙwayoyin cellulose waɗanda aka maye gurbinsu da ƙungiyoyin hydroxyethyl.
4. Neutralization da wanka
Bayan an kammala aikin etherification, abubuwan da ke cikin alkaline a cikin tsarin amsawa suna buƙatar zama neutralized. Abubuwan da aka saba amfani dasu sune abubuwan acidic, kamar acetic acid ko hydrochloric acid. Tsarin tsaka tsaki zai kawar da alkali da suka wuce gona da iri a cikin gishiri, wanda ba zai shafi aikin samfurin ba.
Halin tsaka-tsaki: Ɗauki samfurin daga cikin reactor kuma ƙara adadin acid da ya dace don neutralization har sai ƙimar pH a cikin tsarin ta kai tsaka tsaki. Wannan tsari ba wai kawai yana kawar da ragowar alkali ba, amma kuma yana rage tasirin amsawa ta hanyar samfurori akan aikin hydroxyethyl cellulose.
Wankewa da bushewa: Ana buƙatar wanke samfurin da aka lalata sau da yawa, yawanci tare da ruwa ko ethanol da sauran abubuwan kaushi don wanke ragowar ƙazanta da samfuran. Samfurin da aka wanke yana bushewa ta hanyar centrifugation, tacewa da sauran hanyoyin don rage abun ciki na danshi.
5. bushewa da murƙushewa
Bayan wankewa da bushewa, hydroxyethyl cellulose har yanzu yana ƙunshe da ɗanɗano kaɗan kuma yana buƙatar ƙara bushewa. Ana iya aiwatar da tsarin bushewa ta hanyar bushewa ta iska ko bushewa don tabbatar da cewa samfurin yana da kwanciyar hankali yayin ajiya da amfani.
bushewa: bushe samfurin a wani zazzabi (yawanci ƙasa da 60 ° C) don cire ragowar danshi. Yawan zafin jiki na bushewa bai kamata ya yi girma ba, in ba haka ba yana iya haifar da lalacewar samfur kuma ya shafi aikin sa.
Murkushewa da nunawa: Busasshen hydroxyethyl cellulose yakan kasance a cikin tubalan ko kullutu, kuma dole ne a niƙasa don samun foda mai kyau. The crushed samfurin kuma bukatar da za a tace don samun barbashi size rarraba cewa gana da bukatun don tabbatar da solubility da dispersibility a m aikace-aikace.
6. Gwaji da marufi na samfurori na ƙarshe
Bayan masana'anta, hydroxyethyl cellulose yana buƙatar gwadawa don inganci don tabbatar da cewa alamun aikin sa sun cika daidaitattun buƙatun. Abubuwan gwaji yawanci sun haɗa da:
Ma'aunin danko: Dankowar hydroxyethyl cellulose bayan narkar da ruwa shine muhimmin alamar inganci, wanda ke shafar amfani da shi a cikin sutura, gini, sinadarai na yau da kullun da sauran fannoni.
Abubuwan da ke ciki: Gwada abun ciki na danshi na samfurin don tabbatar da kwanciyar hankalin ajiyar sa.
Digiri na maye (DS) da maye gurbin molar (MS): Ƙayyade matakin maye gurbin da maye gurbin molar a cikin samfur ta hanyar nazarin sinadarai don tabbatar da tasirin tasirin etherification.
Bayan wucewa gwajin, hydroxyethyl cellulose za a kunshe a cikin foda ko granular kayayyakin, yawanci a cikin robobi mai tabbatar da danshi jakunkuna ko takarda don hana shi daga samun damp ko gurɓata.
Tsarin masana'antu na hydroxyethyl cellulose yafi hada da matakai na hakar cellulose, maganin alkalization, amsawar etherification, neutralization da wankewa, bushewa da murkushewa. Dukan tsari ya dogara ne akan alkalization da etherification a cikin maganin sinadarai, kuma ana ba da cellulose mai kyau na ruwa da kaddarorin kauri ta hanyar gabatar da ƙungiyoyin hydroxyethyl. Hydroxyethyl cellulose ne yadu amfani da yawa masana'antu, kamar thickener ga coatings, ruwa-retaining wakili ga gini kayan, stabilizer a yau da kullum sinadaran kayayyakin, da dai sauransu Kowane mahada a cikin samar da tsari bukatar da za a tsananin sarrafawa don tabbatar da high quality da barga yi. na samfurin.
Lokacin aikawa: Oktoba-25-2024