Fabrication of sulfated nanofilter membrane based on carboxymethyl cellulose

The aim of this study is to prepare sulfated carboxymethyl cellulose (SCMC) nanofilter membrane using sulfur trioxide pyridine complex (SO₃/pyridine) as sulfating agent and glutaraldehyde (GA) as a crosslinking agent onto polysulfone supporting membrane. The prepared nanofilter was characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, atomic force microscopy and zeta potential. To evaluate the prepared nanofilter, various amounts of SO₃/Pyridine were used and efficiency of them was investigated. The results showed that increasing the sulfate groups raised the flux from 13.87 to 29.54 L/(m²·h^-1), whereas percentage rejection was increased during the separation of salt aqueous solutions and then decreased. It can be concluded that, SCMC-GA-2 (with molar ratio of SO₃/pyridine to CMC of 1) shows high separation efficiency in acidic conditions and improves the hydrophilicity and charge density of the filter.