Surfactant fouling in pressure-driven membrane processes

The fouling phenomenon of porous polymeric ultrafiltration and nanofiltration membranes was investigated during the purification of solutions containing surfactants. The effects of surfactant type, concentration, and membrane pore size on process performance were evaluated. The highest intensity of membrane fouling was caused by micellar solutions, resulting from the coexistence of monomeric and aggregated surfactant forms. A significant role of hydrophobic/hydrophilic interactions between surfactants and the polymer surface in membrane fouling was proved. Interpretation of the theoretical fouling model showed that cake formation is the dominant fouling mechanism of membranes.