Nano-fibrous sulfonated poly(ether ether ketone) membrane for selective electro-transport of ions

• Published in: Separation and purification technology Vol. 75; no. 2; pp. 174 - 182
• Main Authors: Chakrabarty, Tina, Kumar, Mahendra, Rajesh, K.P., Shahi, Vinod K., Natarajan, T.S.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 13.10.2010; Elsevier
• Subjects: Applied sciences; Cations; Chemical engineering; Drinking water and swimming-pool water. Desalination; Electro-driven separation; Electrospinning; Ethers; Exact sciences and technology; Ion exchange; Ion flux; Ion-exchange membrane; Membranes; Nano-fibrous membrane; Nanocomposites; Nanomaterials; Nanostructure; Pollution; Separation; Water treatment and pollution; Ion flux; Electrospinning; Ion-exchange membrane; Electro-driven separation; Nano-fibrous membrane; Drinking water; Migration; Ion transport; Brackish water; Thin film; Transport process; Ion exchange membrane; Electrolyte; Production; Counter ion; Transport number
• ISSN: 1383-5866; 1873-3794
• DOI: 10.1016/j.seppur.2010.07.019

[Display omitted] ▶ Electrospun nano−fibrous sulfonated poly (ether ether ketone) (ESPEEK) membrane was fabricated onto spun-bonded non-woven polypropylene fabric. ▶ The fibers were found to be fairly uniform and show a narrow distribution in diameter. ▶ The average diameter was found to be 103 nm and the standard deviation was 20 nm. ▶ The electro-dialytic separation of cations (Na + from Mg 2+ or Ca 2+) was achieved using ESPEEK membrane. ▶ ESPEEK membrane may be the promising candidate for electro-dialytic selective separation of ions from their mixture. We reported fabrication of electrospun nano-fibrous ion-exchange membrane (IEM) composed of sulfonated poly(ether ether ketone) (SPEEK). Prepared membrane was employed for electro-dialytic separation of Na + from Mg 2+ or Ca 2+, which is an urgent problem for the production potable water from brackish water and chlor-alkali industries. Nano-fibrous membrane was successfully fabricated onto spun-bonded non-woven polypropylene fabric. Electrospun SPEEK (ESPEEK) and SPEEK thin film membrane's suitability, for the electro-dialytic separation of cations, was assessed by their conductivity measurements under different electrolytic environment using electrochemical impedance spectroscopy. Counter-ion transport number and membrane permselectivity were strongly depended on the nature of counter-ions. ESPEEK membrane showed very low selectivity (about negligible) for Mg 2+ and Ca 2+, because formation of nano-fibrous pore or channels, which restricted the migration of bi-valent cations. Additionally, very low flux and electro-transport efficiency for bi-valent cations in compare with Na + across ESPEEK membrane, suggested its possible application for electro-driven separation of mono-valent and bi-valent electrolytes. Electrospun nano-fibrous IEMs may be the promising candidate for electro-dialytic selective separation of ions depending on their charge and hydrated ionic size.