PFAS cov pa roj carbon activated yog ib hom tshiab ntawm cov kuab paug tsis tu ncua nrog cov tshuaj lom neeg siab, tsis zoo degradability, thiab lwm yam. Lawv tau raug cais raws li qhov tseem ceeb tswj cov pa phem rau cov dej haus los ntawm ntau qhov chaw. Activated carbon adsorption tau dhau los ua cov thev naus laus zis tseem ceeb rau kev tshem tawm PFAS los ntawm dej vim nws cov nqi qis thiab kev ua haujlwm yooj yim. Tab sis, seb nws cov nyhuv purification ua tau raws li qhov yuav tsum tau muaj kev ntsuam xyuas los ntawm peb yam: adsorption kev ua tau zoo, cov qauv yuav tsum tau ua, thiab cov teeb meem ntawm kev siv tswv yim.
Lub peev xwm adsorption ntawm PFAS activated carbon nyob ntawm nws cov qauv pore thiab cov khoom siv tshuaj lom neeg. Cov kev tshawb fawb tau pom tias cov khoom uas muaj cov nplua nuj micropores thiab mesopores muaj peev xwm adsorption sib txawv rau luv - saw thiab ntev - saw hauv PFAS. Xws li, txiv maj phaub plhaub-raws li activated carbon muaj peev xwm adsorption txog li 120 mg/g rau PFOA, tab sis rau PFBS nws tsuas yog 35 mg/g. Tsis tas li ntawd, nto- hloov kho cov pa roj carbon monoxide tuaj yeem txhim kho qhov kev xaiv adsorption ntawm PFAS los ntawm electrostatic attraction lossis hydrogen bonding. Nitric acid oxidation- kho cov pa roj carbon monoxide muaj qhov adsorption tus nqi rau PFOS uas yog 40% siab dua li cov qauv tsis hloov kho, thiab tseem nyob ruaj khov nyob rau hauv cov pa pH ntau ntawm cov dej haus.
Los ntawm qhov kev xav ntawm cov qauv kev lim dej haus, cov teb chaws tau nce kev txwv nruj dua rau PFAS. US EPA tau tshaj tawm cov cai hauv xyoo 2023 tias qhov concentration ntawm PFOA thiab PFOS hauv cov dej haus yuav tsum qis dua 0.004 ng / L thiab 0.02 ng / L, raws li; EU's "Cov Lus Qhia Dej Haus" qhia tias tag nrho PFAS concentration yuav tsum yog<0.5 μg/L. Laboratory static adsorption experiments show that when the activated carbon dosage is 5 g/L and the contact time is 60 minutes, the removal rate of a PFAS solution with an initial concentration of 1 μg/L can reach 99.5%, and the effluent concentration can be reduced to below 5 ng/L, meeting the EU standards. However, in practical applications, dynamic flow conditions can lead to a decrease in the utilization rate of activated carbon adsorption sites and a shortened penetration time. For example, when a water treatment plant using an activated carbon filter treats groundwater containing PFAS, when the filtration speed is increased to 10 m/h, the operating time for PFOA penetration concentration decreases from 72 hours to 48 hours, and activated carbon needs to be frequently replaced to maintain compliance.
Hauv kev siv cov tswv yim, cov tshuab ua kom cov pa roj carbon adsorption tseem ntsib peb qhov teeb meem loj: ua ntej, kev sib tw rau adsorption ntawm PFAS thiab ntuj organic teeb meem; NOM yuav tuav cov chaw nquag ntawm qhov chaw ntawm cov pa roj carbon activated, ua rau 20% -30% txo PFAS tus nqi tshem tawm; Thib ob, qhov nyuaj rau kev ua kom cov pa roj carbon monoxide regeneration, txawm hais tias siab - qhov kub thiab txias tuaj yeem rov qab ua haujlwm adsorption, nws yuav tso PFAS decomposition khoom, ua rau cov pa phem thib ob; thib peb, qhov kev tshawb pom qhov tseeb txwv rau txoj kab PFAS tsuas yog txwv, txoj kev tshawb nrhiav uas twb muaj lawm muaj qhov yuam kev loj heev rau ultra-trace PFAS, ua rau nws nyuaj rau kev txheeb xyuas qhov tseeb seb qhov kev ua kom huv si puas ua tau raws li cov qauv. Nyob rau hauv lub neej yav tom ntej, nws yog ib qho tsim nyog los tsim PFAS activated carbon nrog "porous structure-surface functional group" kev sib koom ua ke kom zoo, ua ke nrog kev kho ua ntej thiab sib sib zog nqus rov tsim dua tshiab, thiab tsim kom muaj PFAS rhiab heev txoj kev tshawb nrhiav los txhawb kev ruaj ntseg ntawm cov dej huv huv cov qauv los ntawm activated carbon adsorption technology.