PSF
(average molecular
weight Mn ≈ 22,000, MO, Sigma-Aldrich) was used for the membrane
support layer. PVP powder (average molecular weight: 360,000, Sigma-Aldrich)
was used as a pore former. Anhydrous dimethyl formamide (DMF) (density:
0.944 g/mL, 99.8% purity, Sigma-Aldrich) was used as a solvent. Deionized
water (MilliPore) was used as a nonsolvent. For the PA rejection layer, m-phenylenediamine (MPD) flakes (molecular weight: 108.14
g/mol, 99% purity, Sigma-Aldrich) and 1,3,5-benzenetricarbonyltrichloride
(TMC) (molecular weight: 265.48 g/mol, 98% purity, Sigma-Aldrich)
were used as reacting monomers. Deionized water (MilliPore) was used
as a solvent for MPD. Hexane (density: 0.672, purity >98.5%, Sigma-Aldrich)
was used as a solvent for TMC. Elicarb MWCNTs (diameter: 10–12
nm, length: tens of micrometers, and density: 1.7–1.9 g/cm3, manufactured by Thomas Swan, England) were used as nanofillers.
H2SO4 (98% purity, Sigma-Aldrich) and HNO3 (purity >69%, Sigma-Aldrich) were used in the oxidation
functionalization
of MWCNTs. Sodium chloride (purity ≥99.5%, FLUKA) was used
for evaluating salt rejection.
(average molecular
weight Mn ≈ 22,000, MO, Sigma-Aldrich) was used for the membrane
support layer. PVP powder (average molecular weight: 360,000, Sigma-Aldrich)
was used as a pore former. Anhydrous dimethyl formamide (DMF) (density:
0.944 g/mL, 99.8% purity, Sigma-Aldrich) was used as a solvent. Deionized
water (MilliPore) was used as a nonsolvent. For the PA rejection layer, m-phenylenediamine (MPD) flakes (molecular weight: 108.14
g/mol, 99% purity, Sigma-Aldrich) and 1,3,5-benzenetricarbonyltrichloride
(TMC) (molecular weight: 265.48 g/mol, 98% purity, Sigma-Aldrich)
were used as reacting monomers. Deionized water (MilliPore) was used
as a solvent for MPD. Hexane (density: 0.672, purity >98.5%, Sigma-Aldrich)
was used as a solvent for TMC. Elicarb MWCNTs (diameter: 10–12
nm, length: tens of micrometers, and density: 1.7–1.9 g/cm3, manufactured by Thomas Swan, England) were used as nanofillers.
H2SO4 (98% purity, Sigma-Aldrich) and HNO3 (purity >69%, Sigma-Aldrich) were used in the oxidation
functionalization
of MWCNTs. Sodium chloride (purity ≥99.5%, FLUKA) was used
for evaluating salt rejection.