Tailored ultra-low pressure nanofiltration membranes for advanced drinking water treatment

Nanofiltration (NF) membranes featuring high water permeance, excellent antifouling properties, and selective organic matter/minerals separation for drinking water are highly desirable in the environmental water treatment process. In this work, an ultra-permeable NF membrane was tailored via a low temperature-assisted interfacial polymerization (LTIP) method. The surface morphologies, structural compositions, and separation performances of the NF membranes were further regulated by changing the addition of the aqueous monomer. The optimized NF membrane (NFM-0.2) showed ultrahigh water permeance of 31.8 L m−2 h−1 bar−1 and 95.1 % Na2SO4 rejection while maintaining superior antifouling behaviors. During the filtration of natural surface water, NFM-0.2 presented 75.5 % higher removals of DOC, UV254, and bisphenol A. The application of NFM-0.2 for filtrating ground water indicated that NFM-0.2 could remove 50.0 % and 62.9 % of organic matter and total hardness, respectively. The permeate water not only had no potential to form scaling after boiling but also preserved mineral ions, which was helpful for providing high-quality drinking water. Combined with the feasibility and practicability of the LTIP method, the facile strategy provides a facile way for tailoring ultralow pressure NF membranes featuring both highly selective separation of organic matter/minerals and superior antifouling abilities for practical water treatment.