Ultrafiltration (UF) yog ib txheej membrane sib cais ntawm microfiltration thiab nanofiltration, nrog rau qhov nruab nrab pore loj ntawm 3-100 nm. Nws ua haujlwm kom huv, cais, thiab mloog zoo rau cov kev daws teeb meem. Nws cov txheej txheem khaws cia feem ntau suav nrog cov nyhuv sieving thiab cov nyhuv electrostatic ntawm daim nyias nyias. Lub lim nruab nrab yog lub ultrafiltration membrane; tsav los ntawm qhov sib txawv ntawm qhov sib txawv ntawm daim nyias nyias, tsuas yog qhov hnyav molecular hnyav solutes thiab dej tuaj yeem dhau mus, yog li ua tiav kev ua kom huv, sib cais, thiab concentration. UF muaj ntau yam kev siv. Qhov ntxov tshaj UF daim nyias nyias siv yog cov tsiaj txhu hauv lub cev. Thaum pib, UF tseem yog ib qho kev sim thiab tsis pom kev txhim kho tseem ceeb kom txog rau thaum xyoo 1970, thaum nws nkag mus rau theem ntawm kev lag luam sai.
Tam sim no (2018), UF membrane cov ntaub ntawv tau nthuav dav los ntawm cellulose acetate (CA) kom suav nrog polystyrene (PS), polyvinylidene fluoride (PVDF), polycarbonate (PC), polyacrylonitrile (PAN), polyethersulfone (PES), thiab nylon (PA), nrog rau qhov hnyav molecular txiav tawm los ntawm 10³ mus rau 10⁶. Vim tias ultrafiltration muaj cov yam ntxwv ntawm cov cuab yeej yooj yim, me me hneev taw, tsis hloov pauv, tsis tshua muaj kev khiav hauj lwm siab, cov khoom siv tsawg, thiab cov khoom siv yooj yim, nws daim ntawv thov tau nthuav dav los ntawm kev tshawb fawb mus rau kev siv tswv yim, xws li electronics, pharmaceuticals, electrophoretic xim, dej haus, khoom noj khoom haus tshuaj, kev kho mob, thiab kev kho dej khib nyiab thiab recycling.