Surfactant-based modification of sodic-Algerian illite clay for the preparation of polymeric membranes: application for separation of iron and zinc ions from aqueous solutions

In the present work, polymer solutions of cellulose triacetate (CTA) and tris-ethylhexyl phosphate (TEHP) mixed with Algerian green illite clay were used to prepare selective filtration membranes by the phase inversion technique via immersion precipitation. The effect of a local clay additive on the structure and performances of the membranes was studied. Algerian clay was characterized by x-ray diffraction (XRD), thermogravimetric analysis (TGA), x-ray fluorescence (XRF) and scanning electron microscopy (SEM). The obtained hybrid membranes were characterized by XRD, Fourier transform infrared spectroscopy (FTIR-ATR), TGA and contact angle measurements. All the synthesized membranes had an amorphous structure without any diffraction peak. This could be due to the absence of crystallization within the membrane. As the plasticizer molecules were hydrophobic, their location at the surface of the modified polymeric membranes is expected to modify the contact angle. Overall, our results show that the addition of plasticizer to the hybrid material (polymer and clay) results in homogeneous and hydrophobic membranes of which the physical properties were ameliorated compared to (CTA+Clay) membranes. As applications, transport of Zn(II) and Fe(III) in polymeric membranes using (CTA+TEHP+Clay) membranes was studied.