Lub hauv paus ntsiab lus ntawm cov tshuaj tiv thaiv cellulose ether hydroxypropyl methyl cellulose: kev tsim cov HPMC hydroxypropyl methyl cellulose siv methyl chloride thiab propylene oxide ua etherification agents. Cov tshuaj tiv thaiv kab mob sib npaug yog: Rcell-OH (cov paj rwb zoo) + NaOH (sodium hydroxide), Sodium hydroxide) + CspanCl (methyl chloride) + CH2OCHCspan (propylene oxide) → Rcell-O -CH2OHCHCspan (hydroxypropyl methylcellulose) + NaClides ( + H2O (dej)
Txheej txheem khiav:
refined paj rwb crushing - alkaliization - pub - alkalization - etherification - hnyav rov qab thiab ntxuav - centrifugal cais - ziab - crushing - sib tov - ntim khoom
1: Cov khoom siv raw thiab cov khoom siv pabcuam rau kev tsim cov hydroxypropyl methylcellulose Cov khoom siv tseem ceeb yog cov paj rwb zoo, thiab cov khoom siv pabcuam yog sodium hydroxide (sodium hydroxide), propylene oxide, methyl chloride, acetic acid, toluene, isopropanol, thiab nitrogen. Lub hom phiaj ntawm refined paj rwb crushing yog ua kom puas lub aggregated qauv ntawm refined paj rwb los ntawm cov neeg kho tshuab lub zog kom txo tau crystallinity thiab polymerization degree thiab nce nws nto.
2: Kev ntsuas thiab cov khoom siv raw khoom zoo tswj: Nyob rau hauv qhov chaw ntawm qee yam khoom siv, qhov zoo ntawm cov khoom siv tseem ceeb thiab cov khoom siv raw thiab qhov sib piv ntawm cov nyiaj ntxiv thiab cov concentration ntawm cov kuab tshuaj ncaj qha cuam tshuam rau ntau yam ntsuas ntawm cov khoom. Cov txheej txheem txheej txheem tsim khoom muaj qee qhov dej, thiab cov dej thiab cov kuab tshuaj organic tsis yog miscible kiag li, thiab cov dej dispersion cuam tshuam rau kev faib cov alkali hauv lub cev. Yog tias nws tsis tau nplawm txaus, nws yuav ua rau tsis zoo rau cov teeb meem alkalization thiab etherification ntawm cellulose.
3: stirring thiab huab hwm coj hloov thiab hloov tshav kub: Cellulose alkalization thiab etherification yog tag nrho cov ua nyob rau hauv heterogeneous ( stirring los ntawm sab nraud quab yuam). Txawm hais tias kev sib cais thiab kev sib cuag ntawm cov dej, alkali, refined paj rwb thiab etherifying tus neeg sawv cev nyob rau hauv cov kuab tshuaj system txaus, yuav ncaj qha cuam tshuam rau alkalization thiab etherification teebmeem. Tsis sib npaug nplawm thaum lub sij hawm alkalization txheej txheem yuav ua rau alkali crystals thiab nag lossis daus nyob rau hauv qab ntawm cov khoom. Sab saum toj txheej concentration yog tsawg thiab alkalization tsis txaus. Yog li ntawd, tseem muaj ntau cov dawb alkali nyob rau hauv lub system tom qab lub etherification tiav. Kev tsis sib xws, ua rau tsis pom tseeb, tsis muaj fiber ntau, tsis muaj dej tuav, tsis tshua muaj gel point, thiab PH tus nqi siab.
4: Cov txheej txheem ntau lawm (slurry ntau lawm txheej txheem)
(1:) Ntxiv cov nqi ntawm cov khoom alkali (790Kg) thiab dej (tag nrho cov dej system 460Kg) rau hauv lub caustic soda kettle, do thiab kub rau qhov kub ntawm 80 degrees rau ntau tshaj 40 feeb, thiab cov khoom alkali yog kiag li yaj.
(2:) Ntxiv 6500Kg ntawm hnyav rau lub reactor (qhov piv ntawm isopropanol rau toluene nyob rau hauv cov kuab tshuaj yog hais txog 15/85); nias lub alkali rau hauv lub reactor, thiab tsuag 200Kg ntawm cov kuab tshuaj rau lub tank alkali tom qab nias lub alkali. Tshem lub raj xa dej; cov tshuaj tiv thaiv lub hwj yog txias rau 23 ° C, thiab pulverized refined paj rwb (800Kg) ntxiv. Tom qab cov paj rwb refined ntxiv, 600Kg ntawm cov kuab tshuaj yog txau los pib cov tshuaj tiv thaiv alkalization. Qhov sib ntxiv ntawm crushed refined paj rwb yuav tsum tau ua kom tiav nyob rau hauv lub sij hawm (7 feeb) (lub sij hawm ntxiv yog tseem ceeb heev). Thaum cov paj rwb refined los rau hauv kev sib cuag nrog cov tshuaj alkali, cov tshuaj tiv thaiv alkalization pib. Yog hais tias lub sij hawm pub mis ntev dhau lawm, qhov degree ntawm alkalization yuav txawv vim lub sij hawm thaum cov paj rwb refined nkag mus rau hauv cov tshuaj tiv thaiv kab mob, uas ua rau uneven alkalization thiab txo cov khoom uniformity. Nyob rau tib lub sijhawm, nws yuav ua rau alkali cellulose nyob rau hauv kev sib cuag nrog huab cua rau lub sij hawm ntev oxidize thiab degrade, ua rau lub viscosity ntawm cov khoom txo. Txhawm rau kom tau txais cov khoom lag luam nrog qib viscosity sib txawv, lub tshuab nqus tsev thiab nitrogen tuaj yeem siv tau thaum lub sij hawm alkalization txheej txheem, los yog ib qho nyiaj ntawm antioxidant (dichloromethane) tuaj yeem ntxiv. Lub sij hawm alkalization yog tswj ntawm 120min, thiab kub yog khaws cia ntawm 20-23 ℃.
(3:) Tom qab alkalization dhau lawm, ntxiv tus nqi ntawm etherifying tus neeg sawv cev (methyl chloride thiab propylene oxide), nce qhov kub thiab txias rau qhov ntsuas kub thiab nqa tawm cov tshuaj tiv thaiv etherification hauv lub sijhawm teev.
Etherification tej yam kev mob: 950Kg ntawm methyl chloride thiab 303Kg ntawm propylene oxide. Ntxiv tus neeg sawv cev etherification thiab txias thiab do rau 40 feeb thiab tom qab ntawd nce qhov kub thiab txias. Thawj etherification kub yog 56 ° C, qhov kub thiab txias lub sij hawm yog 2.5h, qhov thib ob etherification kub yog 87 ° C, thiab qhov kub thiab txias yog 2.5h. Cov tshuaj tiv thaiv hydroxypropyl tuaj yeem mus txog ntawm 30 ° C, cov tshuaj tiv thaiv tau nrawm heev ntawm 50 ° C, cov tshuaj tiv thaiv methoxylation qeeb ntawm 60 ° C, thiab qis dua 50 ° C. Tus nqi, kev faib ua feem thiab sij hawm ntawm methyl chloride thiab propylene oxide, nrog rau qhov kub thiab txias tswj ntawm cov txheej txheem etherification, ncaj qha cuam tshuam rau cov khoom tsim.
Cov khoom siv tseem ceeb rau kev tsim HPMC yog reactor, tshuab ziab khaub ncaws, granulator, pulverizer, thiab lwm yam. Tam sim no, ntau lub tuam txhab txawv teb chaws siv cov khoom tsim hauv lub teb chaws Yelemees. Cov cuab yeej tsim tawm hauv tsev, txawm tias nws muaj peev xwm tsim tau lossis kev tsim khoom zoo, tsis tuaj yeem ua tau raws li qhov xav tau ntawm cov khoom zoo HPMC.
All-In-One Reactor uas tsim nyob rau hauv lub teb chaws Yelemees tuaj yeem ua tiav ntau yam txheej txheem nrog ib lub cuab yeej, paub txog kev tswj tsis siv neeg, cov khoom lag luam ruaj khov, thiab kev ua haujlwm ruaj ntseg thiab txhim khu kev qha.
Cov ntaub ntawv tseem ceeb rau kev tsim HPMC yog cov paj rwb zoo, sodium hydroxide, methyl chloride, thiab propylene oxide.
Post lub sij hawm: Nov-11-2021