The fouling control experiments were carried out at

In the case of BSA, membranes were filtrated by adding 100 mg/l BSA to a 500 mg/l NaCl feed aqueous solution. The time-dependent fluxes of the Laquinimod and modified membranes are presented in Fig. 10, which clearly demonstrates that fouling occurs immediately with all the tested membranes and increases continuously with extending filtration time until it reaches a steady-state after filtration of 80 h. The fouling trend is due to the fast adsorption of BSA on membrane surface through the interaction between BSA molecule and membrane surface and the following relatively slow deposition of BSA through the interaction between the adsorbed BSA and BSA molecules in bulk solution [46]. Table 4 presents the water fluxes of the BSA-fouled and water-cleaned membranes, and the flux decline and recovery ratios of the base and modified membranes. Compared with the base membrane, all the modified membranes experience a smaller flux decline and a higher flux recovery ratio. The enhanced anti-adhesion capability to hydrophobic foulants due to the improved surface hydrophilicity [46] and the endowed steric repulsion effect to the large molecules resulting from the grafted PVA molecules [47] are the two main reasons for the improved fouling resistance and physical cleaning efficiency of the modified membranes.