Surface modification of piperazine-based nanofiltration membranes with serinol for enhanced antifouling properties in polymer flooding produced water treatment

In order to deal with the membrane fouling problem when treating the polymer flooding produced water (PFPW) with a typical thin film composite (TFC) nanofiltration (NF) membrane, a facile and effective serinol surface modification method has been introduced in this study, which is based on the membrane fouling mechanism proposed in our previous research. Serinol molecules were grafted on the nascent piperazine-based PA-TFC membrane through the acylation reaction between the serinol molecule's amino group and the nascent membrane's residual acyl chloride group. A series of characterizations indicated that this modification process could enhance membrane hydrophilicity and decrease the surface carboxyl density without changing the membrane's morphology. Compared with the unmodified PA-TFC membrane, the serinol-grafted PA-TFC membrane had higher water permeability, stronger antifouling ability and equivalent solute rejection, which would be rather meaningful for improving membrane performance when treating PFPW.