Kev vam meej nyob rau hauv cov hluav taws xob dawb carbon (Silicon Dioxide / SiO2)
Dawb cov dub dub lub npe ntawm cov hmoov dawb amorphous silicic acid thiab silicate khoom, mas hais txog cov silicone precipitated, roj theem silica, ultrafine silica gel thiab silica gel, nrog rau cov khoom xyaw txhuas thiab cov calcium uas ntsiag to.
1. Siv roj carbon dawb
Cov roj dawb yog siv los ua cov khoom siv roj hmab, roj hluavtaws, pleev xim, cov khoom siv hluav taws xob, lub tshuab hluav taws xob, thixotropic agent, phosphor precipitant, xim phaj luam tawm, casting pwm tso tus neeg saib xyuas, thiab lwm yam. Cov roj carbon yuav siv tau los ua cov khoom ntim hauv cov polyethylene thiab lwm yam yas. Nws tuaj yeem txhim kho txoj hluav taws xob hluav taws xob ntawm kev siv cable. Ua cov kua nplaum rau ntawm daim ntawv, nws tuaj yeem ua rau kom muaj lub pob dawb thiab opacity ntawm daim ntawv thiab txhim kho nws cov khoom siv dag zog thiab qhov muag. Hauv kev tsim cov khoom ua liaj ua teb, cov dawb cov roj dub siv los ua tus cab kuj los yog siv cov thim rov qab los ntxiv rau kev ua liaj ua teb. Vim nws txoj kev absorbability, yooj yim raug ncua, zoo affinity thiab tshuaj lom neeg ruaj ntseg, nws muaj peev xwm tuav lub txiaj ntsig ntawm qhov khoom.
2, txoj haujlwm txheej txheem ntawm cov roj dawb
Cov txheej txheem tsim cov roj dawb yog cov nag thiab cov pa roj carbon dioxide, thiab cov pa roj carbon dawb ntawm cov pa roj dawb yog dawb amorphous thiab cov khoom sib txig sib txig sib luag (cov khoom me me tsawg tshaj 100nm), tab sis txoj kev npaj ua yog txoj thiab qhov khoom kim, Txoj kev nag lossis daus muaj cov txheej txheem tsom iav thiab kev daus tshwj xeeb, qhov qub yog hais txog sulfuric acid, hydrochloric acid, CO: dej. Cov dawb carbon dub tsim los ntawm lub iav yog siv raws li cov raw cov ntaub ntawv. Cov yav tas los hais txog cov dawb cov roj dub uas tsim los ntawm cov kev siv tshwj xeeb, xws li kev siv tshuab hluav taws xob, cov txheej txheem huab, tshuaj siv lead ua kua, ob txoj kev siv crystallization los yog rov qab micelle microemulsion.
2.1 fumed silica
Tuam Tshoj pib ua cov nplai me me ntawm fumed silica hauv xyoo 2o 60s. Tsuas yog 3 tuam txhab uas muag tau ua cov pa roj carbon dawb dub dub ua ntej xyoo 2002, uas muaj ob leeg tau plaub silicon chloride, thiab lwm tus thawj zaug tau pom tseeb los ntawm methyl peb chlorosilane, los ntawm cov khoom ntawm organosilicon, los tsim roj theem roj carbon dub, raws li "nano silica dub".
Tshuaj vapor deposition (CAV), tseem hu ua pyrolysis, dry method or combustion method, feem ntau yog ua los ntawm siloxane, plaub silicon chloride, rau ethyl siloxane, oxygen (lossis pa) thiab hydrogen, uas hnov mob thaum kub.
Huab cua thiab hydrogen raug xa mus rau lub tshuab hluav taws xob tom qab muaj kev kub ntxhov, sib cais, txias, dehydration, silica gel qhuav, thiab pom cov hmoov av. Tom qab ntawm plaub cov tshuaj silicon chloride tau muab xa tuaj rau sab nrauv, cov evaporator yog cua sov thiab cua txias, thiab cov cua txias thiab cov huab cua lim dej yog siv los ua cov twj tua hluav taws xob, thiab cov plaub silicon chloride vaporized tom siab. Thaum lub ntsuas kub yog 1000 - 1800 C, cov pa roj yog hydrolyzed nrog qee yam hydrogen thiab oxygen (lossis cua) ntawm qhov kub siab txog li 1800 degrees C. Cov roj phaus dej muaj roj ntau, thiab cov roj tsim aerosol , uas yog tsis yooj yim rau kev ntes, kom lub particles yog sau nyob hauv lub aggregator ua ntej thiab mam li sau los ntawm ib qho kev ywj ntses thiab ces xa tawm. Cov kua qaub cawv siv cua uas muaj ammonia rau purge tus fumed silica pH ntawm 4 - 6, uas yog tiav cov khoom.
2.2 ntsig txog silica
Tam sim no, txoj kev los nag siv feem ntau hauv kev lag luam, thiab nws txoj hauv kev yog feem ntau raws li nram no: thaum muaj kub, lub khob dej dej yog npaj los ntawm cov tshuaj tiv thaiv ntawm cov xim quartz (xuab zeb) thiab sodium hydroxide los daws cov kua tshuaj dilute, thiab ces lub silica yog precipitated nyob rau hauv tej yam kev mob thiab ces ntxuav, lim, qhuav thiab crushed kom cov khoom dawb carbon cov dub. Muaj ntau txoj kev rau nag lossis daus, thiab txoj kev ua kua qaub yog txoj kev loj hauv Suav.
2.2.1 kua qaub av
Acid txoj kev yog qhov tshuaj tiv thaiv ntawm soluble silicate nrog sulfuric acid los yog lwm cov kua qaub. Thaum cov tshuaj tiv thaiv ib qho pH nqi, nws nres ntxiv cov kua qaub, kev laus, lim, ntxuav, thiab tshem N% SO, thiab tau cov khoom tom qab ziab thiab tsoo.
Ib daim phiaj duab ntawm cov txheej txheem ntawm kev npaj cov dawb dawb dub los ntawm acid txoj kev
Cov kauj ruam tseem ceeb hauv cov txheej txheem kua qaub yog cov txheej txheem kua qaub, uas yuav tsum tau sim ib qho ntawm ntau ntau yam. Nws tuaj yeem pom los ntawm cov ntaub ntawv hloov nyob rau hauv cov txheej txheem reaction tias cov khoom ntawm cov khoom muaj feem xyuam rau cov kev tswj kev ua haujlwm. Cov dej ua ntsiag to ua ntej yuav dhau mus ua ib qho luaj li cas rau hauv ib qho monomer silicic acid, ib qho tseem yog los tsim cov xoob looj xoob (aggregation), thiab lwm yam ua cov xim colloid (gel tes hauj lwm).
2.2.2 carbonization
Zus tau los ntawm carbonization ntawm carbonization yog raws li cov tshuaj tiv thaiv ntawm carbon dioxide thiab soluble silicate solution los tsim cov dej ua SiO 2 tom qab pom, ziab, crushing thiab ntim.
Ib daim duab ntawm cov txheej txheem carbonization rau kev npaj cov xim dawb dub
Hauv cov txheej txheem no, qhov hloov ntawm sodium silicate tsawg dua, thiab cov khoom siv pom zoo feem ntau yuav tsum tau rov qab soda tshauv los ntawm cov khoom los txo nqi. Qhov chaw ua haujlwm tawm hauv dej kuj tseem muaj cov nyhuv rau cov xim dub. Nws yog qhov zoo uas siv cov polyethylene glycol (6ooo) ua ib tus neeg muag khoom hauv cov pa carbonized dub dub.
Cov khoom siv tshiab ntawm cov txuag dej carbonization yog ua los ntawm cov CO roj thiab dej iav ua raw li cov khoom siv raw, siv cov khoom siv thiab cov khoom siv xws li cov tshuaj tua kab tsuag, kev siv xovxwm tsis zoo, kev siv tshuab hluav taws xob, thiab lwm yam khoom siv thiab cov khoom siv kom ua qib) dawb carbon dub. Cov txheej txheem no muaj qhov sib tiv tauj loj, ceev ceev ceev ceev, txo cov nqi qis thiab nqi pheej yig. Cov khoom ntawm kev tsim, kev khwv tsis zoo, zoo khoom zoo, pom kev lag luam loj, zoo airtight, siab thermal efficiency, cuab yeej hluav taws xob txuag thiab hluav taws xob txuag, ib qho txiaj ntsim rau ib puag ncig thiab kev pab nyiaj txiag zoo tshaj plaws.
2.2.3 cov mineral dissociation thiab lwm cov txheej txheem tshiab
Cov hlau tsis zoo li cov khoom siv rau cov roj dawb yog cov diatomite, protein av, nab, av, av noo, kaolin, wollastonite, quartz sand, sepiolite, attapulgite, fly ash, zircon, thee gangue, daj phosphorus ore. Nws tau tshaj tawm nyob rau hauv cov ntawv nyeem tias cov xim dawb dub los ntawm cov hlau tsis yog xim hlau qhia tau hais tias nws yog kev lag luam thiab kev ua tau zoo, thiab muab txoj kev tshiab rau nws cov kev siv nyiaj.
3. Qhov xaus
(1) silica muaj ntau yam kev siv thiab txawv cov khoom siv sib txawv. Nws yog ib qho tseem ceeb los txais yuav kev yooj yim thiab ntau txoj hauv kev tsim khoom thiab npaj cov roj dawb.
(2) nws yog tsim nyog los ua qhov kev tshawb fawb ntawm kev tsim cov silica los ntawm cov pov tseg (xws li daj phosphorus slag), thiab tsim ib lub tshuab thiab kev lag luam muaj txiaj ntsig.