Incorporation of Al2O3 into cellulose triacetate membranes to enhance the performance of pervaporation for desalination of hypersaline solutions

In this study, nanocomposite membranes were prepared by incorporating alumina (Al 2 O 3 ) nanoparticles into cellulose triacetate (CTA) membranes in order to enhance the performance of pervaporative desalination . The resulting membranes were characterized by SEM, TGA , water contact angle, water uptake , tensile strength , and FTIR. The desalination performance was investigated as a function of Al 2 O 3 loading, feed temperature (ranging from 40 to 70 °C) and feed concentration (varying from 0 g/L to 90 g/L NaCl). Pervaporation (PV) experiments showed that incorporating 2% Al 2 O 3 into a CTA membrane increased the water flux by 204% compared to pristine CTA (from 2.2 kg m −2  h −1 to 6.7 kg m −2  h −1 ) for a 30 g/L NaCl feed solution at 70 °C, while the salt rejection remained above 99.8%. Moreover, when the CTA-2% Al 2 O 3 nanocomposite membrane was tested with a 90 g/L feed solution, only 25% flux reduction without sacrificing the salt rejection. Furthermore, different feed concentration affected the activation energy of water molecules to diffuse through pristine CTA and CTA/Al 2 O 3 nanocomposite membrane. However, the nanocomposite membrane has a lower apparent activation energy even at high NaCl concentrations, compared to the pristine CTA. This suggests that the developed CTA/Al 2 O 3 nanocomposite membrane is suitable for desalting hypersaline water.