Microbial desalination cell with sulfonated sodium (poly(ether ether ketone) as cation exchange membranes for enhancing power generation and salt reduction

Publication date:

Available online 9 February 2018

Source:Bioelectrochemistry

Author(s): Francisco Lopez Moruno, Juan E. Rubio, Plamen Atanassov, José M. Cerrato, Christopher G. Arges, Carlo Santoro

Microbial desalination cell (MDC) is a bioelectrochemical system capable of oxidizing organics, generating electricity and reduce the salinity content into the desalination chamber. As it is designed, anion and cation exchange membranes play an important role on the selective removal of ions from the desalination chamber. In this work, sulfonated sodium (Na⁺) poly(ether ketone) (SPEEK) cation exchange membranes (CEM) were tested in combination with quaternary ammonium chloride poly(2,6-dimethyl 1,4-phenylene oxide) (QAPPO) anion exchange membrane (AEM). Non-patterned and patterned (with increased, lateral different topographical features) CEMs were investigated and assessed in this work. The results were contrasted against a commercially available CEM. This work used real seawater from the Pacific Ocean in the desalination chamber. The results displayed a high desalination rate and power generation for all the membranes, with a maximum of 78.6 ± 2.0% in salinity reduction and 235 ± 7 mW m⁻² in power generation for the MDCs with a non-patterned (i.e., flat) CEM. Desalination rate and power generation achieved are higher with synthesized SPEEK membranes when compared with an available commercial CEM. An optimized combination of these types of membranes substantially improves the performances of this bioelectrochemical system, making the system more suitable for real applications.