Hydroxypropyl Methyl Cellulose Eteri Technology

Hydroxypropyl methyl cellulose ether imhando yenonpolar cellulose ether inonyungudika mumvura inotonhora inowanikwa kubva kune yakasikwa cellulose kuburikidza nealkalization uye etherification shanduko.

Keywords:hydroxypropyl methylcellulose ether; alkalization reaction; etherification reaction

1. Technology

Natural cellulose haina kunyungudika mumvura uye organic zvinonyungudutsa, inogadzikana kuchiedza, kupisa, asidhi, munyu uye mamwe makemikari media, uye inogona kunyoroveswa mu dilute alkali mhinduro yekushandura pamusoro peserulosi.

Hydroxypropyl methyl cellulose ether imhando isiri-polar, inotonhora-inonyungudika mvura selulosi ether inowanikwa kubva kune yakasikwa cellulose kuburikidza nealkalization uye etherification shanduko.

2. Iyo huru yemakemikari reaction formula

2.1 Alkalization reaction

Pane nzira mbiri dzekuita kwe cellulose uye sodium hydroxide, kureva, maererano nemamiriro akasiyana ekugadzira mamorekuru emakemikari, R - OH - NaOH; kana kugadzira simbi doro makemikari, R - ONa.

Nyanzvi dzakawanda dzinotenda kuti cellulose inopindirana ne-concentrated alkali kuti iite chinhu chakagadziriswa, uye inofunga kuti rimwe nerimwe kana maviri mapoka eglucose anosanganiswa neAOH molecule (imwe boka reglucose rinosanganiswa nemamolekemu matatu eNaOH kana mhinduro yapera).

C6H10O5 + NaOH→C6H10O5 NaOH kana C6H10O5 + NaOH→C6H10O4 ONa + H2O

C6H10O5 + NaOH→(C6H10O5 ) 2 NaOH kana C6H10O5 + NaOH→C6H10O5 C6H10O4 ONa + H2O

Munguva ichangopfuura, dzimwe nyanzvi dzinotenda kuti kudyidzana pakati pe cellulose uye yakadzika alkali ichava nemigumisiro miviri panguva imwe chete.

Zvisinei nechimiro, kuita kwemakemikari e cellulose kunogona kushandurwa mushure mekuita kwe cellulose uye alkali, uye inogona kuita neakasiyana makemikari media kuti iwane zvine musoro mhando.

2.2 Etherification maitiro

Mushure me alkalization, iyo inoshanda alkali cellulose inobatana ne etherification agent kuita cellulose ether. Iyo etherifying agents inoshandiswa ndeye methyl chloride uye propylene oxide.

Sodium hydroxide inoita senge catalyst.

n uye m inomiririra dhigirii rekutsiva hydroxypropyl uye methyl pane cellulose unit, zvichiteerana. Huwandu hwepamusoro hwem + n ndeye 3.

Pamusoro peiyo yataurwa pamusoro maitiro makuru, pane zvakare maitiro epadivi:

CH2CH2OCH3 + H2O→HOCH2CH2OHCH3

CH3Cl + NaOH→CH3OH + NaCl

3. Tsanangudzo yemaitiro ehydroxypropyl methylcellulose ether

Iyo nzira yehydroxypropyl methyl cellulose ether ("cellulose ether" kwenguva pfupi) inoumbwa nemaitiro matanhatu, anoti: mbishi kupwanya, (alkalinization) etherification, kubviswa kwesolvent, kusefa uye kuomesa, kupwanya uye kusanganisa, uye kupedzwa kwechigadzirwa kurongedza.

3.1 Kugadzirira kwezvinhu

Iyo yakasikwa pfupi-lint cellulose inotengwa mumusika inopwanyika kuita upfu ne pulverizer kufambisa kunotevera kugadzirisa; iyo alkali yakasimba (kana mvura alkali) inonyungudutswa uye yakagadzirwa, uye inopisa kusvika makumi mapfumbamwe°C kugadzira 50% caustic soda solution yekushandisa. Gadzirira mhinduro methyl chloride, propylene oxide etherification agent, isopropanol uye toluene reaction solvent panguva imwe chete.

Mukuwedzera, maitiro ekuita anoda zvinhu zvekubatsira zvakadai semvura inopisa uye mvura yakachena; chiutsi, mvura inotonhodza yakaderera, uye mvura inotonhorera inotenderera inodiwa kubatsira simba.

Mapfupi linters, methyl chloride, uye propylene oxide etherification agents ndizvo zvinhu zvikuru zvekugadzira etherified cellulose, uye marita mapfupi anoshandiswa muhuwandu. Methyl chloride uye propylene oxide inotora chikamu mukuita se etherification maajenti kugadzirisa yakasikwa cellulose, huwandu hwekushandiswa hauna hukuru.

Solvents (kana diluents) inonyanya kusanganisira toluene uye isopropanol, izvo zvisingadyiwi, asi mukuona kwekurasikirwa kwakadzikama uye kunopisa, pane kurasikirwa kudiki mukugadzirwa, uye mari inoshandiswa idiki kwazvo.

Iyo mbishi gadziriro yekugadzira ine mbishi tangi nzvimbo uye yakasungirirwa mbiru yekuchengetera zvinhu. Etherifying agents uye zvinonyungudutsa, zvakadai se toluene, isopropanol, uye acetic acid (inoshandiswa kugadzirisa pH kukosha kwezvinogadzirisa), zvinochengetwa munzvimbo yetangi. Kupihwa kweiyo short lint yakakwana, inogona kupihwa nemusika chero nguva.

Iyo yakapwanyika lint pfupi inotumirwa kumusangano nengoro yekushandisa.

3.2 (Alkalinization) etherification

(Alkaline) etherification inzira yakakosha mukuita etherification ye cellulose. Mune yekutanga nzira yekugadzira, maitiro maviri-matanho akaitwa akaparadzana. Iye zvino maitiro anovandudzwa, uye maitiro maviri-matanho anosanganiswa muchikamu chimwe uye anoitwa panguva imwe chete.

Chekutanga, tsvaira tangi ye etherification kuti ubvise mweya, wobva waitsiva nenitrogen kuita kuti tangi ive isina mweya. Wedzera yakagadziriswa sodium hydroxide solution, wedzera imwe chiyero che isopropanol uye toluene solvent, tanga kubvongodza, wobva wawedzera shinda pfupi, vhura mvura inotenderera kuti itonhorere, uye mushure mekunge tembiricha yadonha kune imwe nhanho, vhura iyo yakaderera-. tembiricha yemvura yekudzikisa iyo system zvinhu tembiricha Drop to about 20℃, uye chengetedza maitiro kune imwe nguva yenguva yekupedzisa alkalization.

Mushure me alkalization, wedzera iyo etherifying agent methyl chloride uye propylene oxide yakayerwa nepamusoro-level metering tank, ramba uchitanga kubvongodza, shandisa chiutsi kukwidza tembiricha kusvika ku70.℃~ 80℃, uye ipapo shandisa mvura inopisa kuti uenderere mberi nekudziya nekuchengetedza Kupisa kwekuita kunodzorwa, uye ipapo kupisa kwekuita uye nguva yekuita zvinodzorwa, uye kushanda kunogona kupedzwa nekukurudzira uye kusanganisa kweimwe nguva yenguva.

Kuita kunoitwa panosvika makumi mapfumbamwe°C uye 0.3 MPa.

3.3 Kuparara

Izvo zvataurwa pamusoro apa zvakagadziriswa maitiro zvinotumirwa kune desolventizer, uye zvinhu zvinobviswa uye zvinopisa nemhepo, uye toluene uye isopropanol solvents inoputika uye inodzorerwa kuti idzoke zvakare.

Iyo evaporated solvent inotanga kunyoroveswa uye yakanyungudutswa zvishoma nemvura inotenderera, uyezve yakanyungudutswa nemvura yakadzika-kupisa, uye musanganiswa we condensate unopinda mumvura yemvura uye separator kuti iparadzanise mvura uye inonyungudutsa. Iyo yakasanganiswa solvent ye toluene uye isopropanol muhupamhi hwepamusoro inogadziriswa muchiyero. Ishandise zvakananga, uye dzorera mvura uye isopropanol mhinduro muchikamu chezasi kune desolventizer kuti ishandiswe.

Wedzera acetic acid kune reactant mushure mekuparadzwa kuti uite neutralize yakawandisa sodium hydroxide, wozoshandisa mvura inopisa kugeza zvinhu, shandisa zvizere coagulation hunhu hwe cellulose ether kumvura inopisa kugeza cellulose ether, uye gadzirisa reactant. Zvinhu zvakanatswa zvinotumirwa kune inotevera nzira yekuparadzanisa uye kuomeswa.

3.4 Sefa uye woomesa

Iyo yakanatswa inotumirwa kune yakachinjika screw separator ne-high-pressure screw pump kuti iparadzanise mvura yemahara, uye iyo yakasara yakasimba zvinhu inopinda mumhepo dryer kuburikidza ne screw feeder, uye inoomeswa inosangana nemhepo inopisa, yobva yapfuura nemudutu. separator uye mhepo Kuparadzana, iyo yakasimba zvinhu inopinda mukupwanya kunotevera.

Mvura yakapatsanurwa nehorizontal spiral separator inopinda mutangi rekuchenesa mvura mushure mekunyunguduka mudhangi resedimentation kuti iparadzanise cellulose yakaiswa.

3.5 Kupwanya nekusanganisa

Mushure mekuomeswa, iyo etherified cellulose ichave isina kuenzana particle size, iyo inoda kupwanyiwa uye kusanganiswa kuitira kuti particle size kugovera uye kutaridzika kwese kwechigadzirwa kunosangana nezvinodiwa zvechigadzirwa.

3. 6 Yakapedzwa chigadzirwa kurongedza

Zvinhu zvakawanikwa mushure mekupwanya uye kusanganisa mashandiro ndiyo yakapedzwa etherified cellulose, inogona kuiswa mukati uye kuiswa mudura.

4. Pfupiso

Mvura yakaparadzana yakaparadzana ine imwe munyu, kunyanya sodium chloride. Mvura yakaraswa inonyungudutswa kuti iparadzanise munyu, uye mupfunga wechipiri wakaputika unogona kudzoreredzwa kuti udzore mvura yakatsikirirwa, kana kubudiswa zvakananga. Chinhu chikuru chemunyu wakapatsanurwa ndeye sodium chloride, iyo inewo imwe chiyero chesodium acetate nekuda kwe neutralization neacetic acid. Uyu munyu une kukosha kwekushandiswa kwemaindasitiri chete mushure mekugadzirisazve, kupatsanurwa uye kucheneswa.