Improving MFI-UF constant flux to more accurately predict particulate fouling in RO systems: Quantifying the effect of membrane surface porosity

This study aimed to quantify the effect of membrane surface porosity on particulate fouling predicted by MFI-UF method at constant flux. Firstly, polyethersulfone UF membranes (5–100 kDa) was determined using ultra-high resolution SEM. Thereafter, measured suspensions polystyrene particles (75 nm), which were pre-washed remove surfactant and particle fractions smaller than pores membranes, thus ensuring complete retention during measurements. Consequently, values washed independent pore size depended only membrane. The results showed that decreased with MWCO from 10.5% (100 0.6% (5 kDa), consequently increased 3700 8700 s/L 2 , respectively. increase in attributed non-uniform distribution pores, is exacerbated as decreases. preliminary correction factors 0.4–1.0 proposed for range 5–100 kDa. Finally, applied predict a full-scale RO plant. However, additional research required establish different types feed water. • Novel approach allows quantification MFI-UF. Washed used investigate effect. Effect depends how uniform are distributed. Low can result overestimation value. Surface improved prediction an plan.