Preparation and characterization of TiO₂-sulfonated polymer embedded polyetherimide membranes for effective desalination application

Nanocomposite polyetherimide/TiO₂-sulfonated polymer membranes were fabricated by phase inversion process, using Dimethylacetamide as solvent. The sulfonated polymers such as sulfonated poly(ether ether ketone) (SPEEK) and sulfonated polyethersulfone (SPES) self-assemble with TiO₂ to form resultant hybrid PEI membranes. Such hybrid membranes were characterized by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, contact angle, scanning electron microscopy (SEM) and LCR meter. Among these membranes, TiO₂-SPEEK incorporated PEI membrane shows a higher flux of 44.75L/m²h and lesser contact angle value of 61.38°. It is observed that such combination improves the membrane surface functionality. In addition, the filtration of three different electrolytes (NaCl, Na₂SO₄ and MgSO₄) with varying concentrations from 50 to 500mg/L on resulted membranes was analyzed. It is inferred that an increasing dielectric constant value increased the salt rejection in such membranes. Also, a higher retention coefficient of 0.72 was observed during filtration of Na₂SO₄ using PEI/SPEEK/TiO₂ membrane. Effects of ground water on flux profile and flux reduction ratio in the fabricated membrane were also analyzed and discussions are provided.