Cationic dye (MB) removal using polymer inclusion membrane (PIMs)

Studies were carried out to remove a basic dye (Methylene Blue; MB) from their aqueous solutions using polymer inclusion membranes (PIMs) consisting of Cellulose Triacetate (CTA) as the base polymer, 2-Nitrophenyl octyl ether (2-NPOE) as the plasticizer and Di-(- Ethyl hexyl) phosphoric acid (D2EHPA) as the carrier. The manufactured membranes have been characterized by Scanning Electron Microscopy (SEM) (morphology), Fourier Transform Infrared Spectroscopy (FTIR) (chemical structure) and TGA (thermal analysis). The membranes thickness was measured by digital micrometer. The fractions of base polymers and of the carrier D2EHPA were varied to determine the optimum composition with respect to extraction capability of the membranes. After optimization of the pH of the aqueous solution, the concentration of D2EHPA in the membrane, the concentration of the MB and the stirring speed, more than 93% extraction efficiency has been reached at pH = 6.0. The chemical formula of the complex (D2EHPA-MB) extracted by the PIMs was determined by the method of slopes.