Silicon Dioxide

Silicon dioxide (cov tshuaj formula: SiOz) yog ib qho acidic oxide, cov hydrate sib xws yog silicic acid (H2SiOs), silicon dioxide yog ib qho tseem ceeb tshaj plaws ntawm silicon. Lub ntuj silica uas twb muaj lawm nyob rau hauv lub ntiaj teb muaj txog li 12% ntawm qhov loj ntawm lub crust, thiab nws cov ntaub ntawv muaj nyob yog crystalline thiab amorphous ob pawg, collectively hu ua silica.

Xa kev nug

Khoom Taw qhia

Khoom Description

Silica tseem hu ua silica, tshuaj formula SiO₂. Muaj ob hom crystalline silica thiab amorphous silica nyob rau hauv qhov xwm txheej. Vim yog cov qauv siv lead ua sib txawv, crystalline silica tuaj yeem muab faib ua peb hom: quartz, squamous quartz thiab cristobalite. Ntshiab quartz yog cov xim tsis muaj xim, thiab loj thiab pob tshab prismatic quartz hu ua siv lead ua. Yog tias cov khoom siv lead ua muaj cov kab tsis huv muaj cov xim sib txawv, muaj amethyst, tshuaj yej siv lead ua, number case crystal thiab lwm yam. Ordinary xuab zeb yog ib tug zoo quartz siv lead ua, nrog daj xuab zeb (ntau hlau impurities) thiab dawb xuab zeb (tsawg impurities, ntau ntshiab).

intro

►Kev siv yooj yim

1.Silicon dioxide yog kev tsim cov iav, quartz iav, dej iav, optical fiber, hluav taws xob kev lag luam tseem ceeb Cheebtsam, optical instruments, crafts thiab refractory cov ntaub ntawv, yog ib yam khoom tseem ceeb rau kev tshawb fawb. 2.Kev siv ntawm silica: iav tiaj tus, iav khoom, casting xuab zeb, iav fiber ntau, ceramic glaze, xuab zeb blasting rau xeb tiv thaiv, xuab zeb rau pom, flux, refractory thiab siv ntawm Autoclaved Lightweight Concrete. Silica muaj ntau yam siv. Cov crystals tsis tshua muaj nyob rau hauv cov xwm txheej tuaj yeem siv los tsim cov khoom tseem ceeb ntawm kev lag luam hluav taws xob, cov cuab yeej kho qhov muag thiab cov khoom siv tes ua, thiab silicon dioxide yog cov khoom siv tseem ceeb rau kev tsim cov fiber ntau. Feem ntau cov ntshiab quartz, tuaj yeem siv los ua quartz iav, quartz iav expansion coefficient tsawg heev, sib npaug rau cov iav zoo tib yam 1/18, tuaj yeem tiv taus qhov kub thiab txias, zoo acid kuj (tshwj tsis yog HF), yog li ntawd, quartz iav feem ntau siv los ua cov cuab yeej siv tshuaj tiv thaiv kub kub. Quartz xuab zeb feem ntau yog siv los ua iav raw khoom thiab cov khoom siv hauv tsev.

46f985d044414b80bb97f29561be7d46

► Synthesis method

1. Ion exchange method: Lub diluted dej iav yog lim kom tshem tawm impurities los ntawm cation exchange, anion exchange, pH tus nqi hloov, evaporation los yog ultrafiltration concentration, silica sol yog npaj.

2. Silica hmoov txoj kev: Distilled dej thiab sodium hydroxide (qib reagent) yog ntxiv rau cov tshuaj tiv thaiv tank, qhov kub yog nce mus rau 65 degree, ib tug tej yam nqi ntawm ammonia yog ntxiv los kho cov alkalinity, thiab silica hmoov yog ntxiv nyob rau hauv batches nyob rau hauv agitation, thiab kub yog tswj hauv qab 8.3 degree. Tom qab cov hmoov silica ntxiv, nws txuas ntxiv mus rau 2 ~ 3h, thiab thaum tus nqi pH raug txo mus rau 9 ~ 10, cov qauv raug tshuaj xyuas, thiab cov tshuaj tiv thaiv txias rau 50 degree hauv kev ntxhov siab tom qab cov tshuaj tiv thaiv tiav. Silica sol khoom tau npaj. Cov hmoov silica uas tsis muaj tshuaj tiv thaiv tuaj yeem rov qab tau thiab rov siv dua.

3. Sulfuric acid txoj kev: lub diluted dej iav thiab dilute sulfuric acid yog tov ntawm 20 ~ 30 degree rau cov tshuaj tiv thaiv los tsim silicon gel, laus rau 4h, soaked nrog 2% ~ 2.5% dilute sulfuric acid rau 1h, ntxuav nrog dej ntawm 40 ~ 50 degree, lub cev qhuav dej rau cov ntsiab lus dej s80% nyob rau hauv lub tshuab ziab khaub ncaws, qhuav rau cov dej ntsiab lus s10%, thiab qhib rau hauv qhov cub ua kom sov ntawm 500 ~ 550 degree. Cov coarse pore microspheres tau npaj los ntawm kev tshuaj ntsuam.

4 Thaum refining npua hlau, cov khib nyiab pov tseg muaj silica.