Formaldehydeyog ib qho tshuaj tshaib plab heev nrog qee yam toxicity. Lub sij hawm ntev raug rau formaldehyde muaj teeb meem rau tib neeg lub cev. Txawm li cas los xij, thaum cov ntsiab lus tsis dhau tus qauv, nws kuj tuaj yeem pab peb lub neej txhua hnub hauv ntau txoj hauv kev.
Formalin yog dav siv hauv kev ua liaj ua teb, kev lag luam thiab tshuaj. Ntxiv nrog rau kev siv ncaj qha los ua tshuaj tua kab mob, ua kom tsis muaj menyuam thiab khaws cia, formaldehyde feem ntau yog siv hauv cov organic synthesis, cov khoom siv hluavtaws, txheej, roj hmab, tshuaj tua kab thiab lwm yam lag luam. Nws cov derivatives feem ntau suav nrog paraformaldehyde, polyformaldehyde, phenolic resin, urea formaldehyde resin, amino resin Urotor khoom thiab polyols, thiab lwm yam. Kev lag luam vaj huam sib luag ntoo yog tsim, thiab muaj kev thov zoo heev rau formaldehyde. Formaldehyde muaj ntau yam kev siv. Nws yog siv rau hauv cov khoom siv hluavtaws, surfactant, plastics, roj hmab, tawv, papermaking, dyes, pharmaceuticals, tshuaj tua kab, yees duab films, explosives, tsev ntaub ntawv, tshuaj tua kab mob, fumigation thiab anti-corrosion. Nws tuaj yeem hais tias formaldehyde yog ib tus kws tshaj lij hauv kev lag luam tshuaj, tab sis yuav tsum muaj kev txwv thiab tus qauv siv rau txhua yam, Thaum siv tshaj li cov qauv thiab kev txwv, nws yuav ua rau muaj qhov tsis zoo. Nyob rau hauv xyoo tas los no, cov khoom tsim tawm ntawm formaldehyde nyob rau hauv Tuam Tshoj tau nce xyoo los ntawm lub xyoo, uas yog raws li kev loj hlob ntawm Tuam Tshoj' s textile kev lag luam thiab cov khoom siv hauv tsev. Vim tias nws tus nqi qis thiab kev lag luam dav dav, formaldehyde tseem yuav yog tus hlub ntawm Tuam Tshoj' kev lag luam tshuaj lom neeg rau lub sijhawm ntev yav tom ntej.
Formaldehyde yog npaj los ntawm catalytic oxidation ntawm methanol hauv kev lag luam. Kev sib xyaw ntawm methanol vapor thiab cua yog absorbed los ntawm dej los ntawm cov nyiaj catalyst ntawm 600 ~ 700 ° C los tsim formaldehyde thiab unactive methanol. Tom qab tshem tawm ib feem ntawm methanol los ntawm cov tshuaj, cov aqueous tov ntawm formaldehyde yog tau, uas muaj 40% formaldehyde thiab 8% ~ 10% methanol. Cov tshuaj aqueous no hu ua' formalin'
Hauv kev npaj cov tshuaj formalin (cov tshuaj ruaj khov lossis cov tshuaj khaws cia), 37 - 40% cov tshuaj formalin yuav tsum tau siv ua kua. Piv txwv li, thaum npaj 5% tov, 5 mL thiab 95 mL distilled dej ntawm 37 - 40% tov yuav tsum tau tov, uas kuj yog ib qho kev npaj siv feem ntau hauv chav kuaj.
Formalin, muab tso rau hauv lub raj mis yas zoo kaw hauv qhov ntxoov ntxoo. Qhov ntsuas kub cia yog cuam tshuam nrog cov concentration ntawm formaldehyde tov thiab tuaj yeem xam los ntawm cov qauv, uas yog," cia kub = (concentration tus nqi + 5) ℃", yog li qhov ntsuas kub yog feem ntau nyob nruab nrab ntawm 15 ° C thiab 25 ° C.
Formalin yog khaws cia rau hauv lub tub yees los yog nyob rau hauv chav tsev kub rau lub sij hawm ntev. Dawb precipitates tuaj yeem ua rau hauv cov kua dej aqueous, uas yog, paraformaldehyde. Yog tias nws rhaub, nws tuaj yeem ua kua. Yog li ntawd, formalin tsis haum rau lub tub yees hauv lub tub yees, txwv tsis pub nws yooj yim rau agglomerate. Rau cov tshuaj aqueous nrog formalin cov ntsiab lus ntawm 35% mus rau 40% (feem ntau 37%), 10% ~ 15% methanol kuj ntxiv los tiv thaiv polymerization.