Cov txheej txheem pulping ntawm cellulose ethers koom nrog ob peb kauj ruam ntawm kev rho tawm cellulose los ntawm cov khoom siv raw thiab tom qab hloov nws mus rau hauv cellulose ethers. Cellulose ethers yog ntau yam sib txuas nrog rau kev siv ntau yam kev lag luam, suav nrog tshuaj, khoom noj, textiles thiab kev tsim kho. Cov txheej txheem pulping yog qhov tseem ceeb kom tau txais cov khoom zoo ntawm cov cellulose, cov khoom siv raw rau kev tsim cov cellulose ethers. Cov hauv qab no yog cov lus piav qhia ntxaws txog cov txheej txheem cellulose ether pulping:
1. Raw khoom xaiv:
Cov txheej txheem pulping pib nrog kev xaiv cov khoom siv raw uas muaj cellulose. Cov chaw muaj xws li ntoo, paj rwb, thiab lwm yam nroj tsuag fibers. Kev xaiv cov khoom siv raw yog nyob ntawm cov yam ntxwv xws li cellulose ether muaj, tus nqi thiab cov khoom xav tau.
2. Pulp ua txoj kev:
Muaj ntau txoj hauv kev ntawm cellulose pulping, feem ntau suav nrog tshuaj pulping thiab mechanical pulping.
3. Tshuaj Pulping:
Kraft pulping: Koom nrog kev kho ntoo chips nrog kev sib xyaw ntawm sodium hydroxide thiab sodium sulfide. Cov txheej txheem no dissolves lignin, tawm hauv qab cellulosic fibers.
Sulfite pulping: Siv sulfurous acid los yog bisulfite los rhuav tshem lignin hauv cov khoom noj.
Organic solvent pulping: Siv cov kuab tshuaj organic xws li ethanol lossis methanol kom yaj lignin thiab cais cov cellulose fibers.
4. Mechanical pulping:
Pob zeb-hauv av ntoo pulping: Koom nrog kev sib tsoo ntoo ntawm pob zeb kom sib cais cov fibers.
Refiner Mechanical Pulping: Siv lub zog siv hluav taws xob los cais cov fibers los ntawm kev ua kom zoo nkauj ntoo.
5. Ua kom dawb huv:
Tom qab pulping, cellulose tau ua cov txheej txheem bleaching kom tshem tawm impurities thiab xim. Cov tshuaj chlorine, chlorine dioxide, hydrogen peroxide lossis cov pa oxygen tuaj yeem siv thaum lub sij hawm bleaching.
5.. Kev hloov kho cellulose:
Tom qab purification, cellulose yog hloov los tsim cellulose ethers. Cov txheej txheem muaj xws li etherification, esterification thiab lwm yam tshuaj lom neeg los hloov lub cev thiab tshuaj lom neeg ntawm cellulose.
6. Etherification txheej txheem:
Alkalization: Kho cellulose nrog alkali (feem ntau yog sodium hydroxide) los tsim alkali cellulose.
Ntxiv cov etherifying agents: Alkaline cellulose reacts nrog etherifying agents (xws li alkyl halides los yog alkylene oxides) los qhia ether pawg rau hauv cov qauv cellulose.
Neutralization: Neutralize cov tshuaj tiv thaiv sib tov kom tshem tawm cov tshuaj tiv thaiv thiab tau txais cov khoom uas xav tau cellulose ether.
7. Ntxuav thiab ziab:
Cov khoom siv cellulose ether yog ntxuav kom tshem tawm cov khoom lag luam thiab impurities. Tom qab ntxuav, cov khoom yog qhuav kom ua tiav cov ntsiab lus noo noo xav tau.
8. Sib tsoo thiab tshuaj ntsuam:
Qhuav cellulose ethers tuaj yeem ua hauv av kom tau txais qhov loj me me. Sieving yog siv los cais cov khoom ntawm qhov xav tau loj.
8. Kev tswj kom zoo:
Kev tswj xyuas kev ua tau zoo yog siv los xyuas kom meej tias cellulose ethers ua tau raws li cov qauv teev tseg. Qhov no suav nrog kev ntsuas viscosity, qib ntawm kev hloov pauv, cov ntsiab lus noo noo thiab lwm yam tsis raug.
9. Ntim thiab xa khoom:
Qhov kawg cellulose ether khoom yog ntim thiab xa mus rau ntau yam kev lag luam. Kev ntim khoom kom zoo kom ntseeg tau tias cov khoom zoo yog khaws cia thaum khaws cia thiab kev thauj mus los.
Cov txheej txheem pulping ntawm cellulose ether yog ib tug complex ntawm cov kauj ruam uas muaj kev xaiv raw khoom, pulping txoj kev, bleaching, cellulose hloov, etherification, ntxuav, ziab, sib tsoo thiab tswj kom zoo. Txhua kauj ruam yog qhov tseem ceeb hauv kev txiav txim siab qhov zoo thiab cov khoom ntawm cellulose ether tsim, ua rau nws haum rau ntau yam kev siv. Kev txhim kho thev naus laus zis txuas ntxiv txhim kho thiab ua kom zoo dua cov txheej txheem no txhawm rau txhim kho kev ua tau zoo thiab kev ruaj khov ntawm cellulose ether ntau lawm.
Post lub sij hawm: Jan-15-2024