Two-compartment bipolar membrane electrodialysis for splitting of sodium formate into formic acid and sodium hydroxide: Modelling

Jesus Salvador Jaime-Ferrer (1) , Estelle Couallier (1) , Philippe Viers (1) , Mohammed Rakib (1)

1 LGPM - Laboratoire de Génie des Procédés et Matériaux - EA 4038

The aim of this work is to model the two-compartment bipolar membrane electrodialysis for organic salts acidification. The salt studied is sodium formate which splits into formic acid and sodium hydroxide thanks to water splitting by bipolar membrane. The contamination of sodium hydroxide by formate ion is due to diffusion of molecular formic acid through the bipolar membrane and to leakage of formate ion through the same membrane under the applied current. The cation-exchange membrane does not participate to contamination of sodium hydroxide. But the leakage of hydroxide ion through the cationexchange membrane is the major factor influencing the current efficiency of electrodialysis. The average current efficiency decreases with time principally because the sodium hydroxide concentration increases.

Keywords: Bipolar membrane electrodialysis; Two-compartment electrodialysis; Salt splitting; Formic acid; Modelling

Domains: Engineering Sciences [physics]; Chemical and Process Engineering

Jesus Salvador Jaime-Ferrer, Estelle Couallier, Philippe Viers, Mohammed Rakib. Two-compartment bipolar membrane electrodialysis for splitting of sodium formate into formic acid and sodium hydroxide: Modelling. Journal of Membrane Science, 2009, 328, pp.75-80. ⟨10.1016/j.memsci.2008.10.058⟩. ⟨hal-00789483⟩