Electrodialytic water splitting process for gaseous products

Abstract

The present invention provides an improved electrodialytic water splitting process that may be operated in two- or three-compartment cells to recover valuable metal or ammonium values from materials comprising a salt of a first acid while avoiding formation of gas bubbles in the two- or three-compartment electrodialytic water splitting cells. The process comprises contacting a material comprising a salt of a first acid e.g. Na.sub.2 SO.sub.3, Na.sub.2 CO.sub.3 /NaHCO.sub.3, wherein the first acid is capable of generating a gas upon acidification of the salt of the first acid with a hydrogen ion-enriched aqueous solution comprising a second acid, e.g. Na.sub.2 SO.sub.4 /H.sub.2 SO.sub.4 which is generated and withdrawn from a two- or three-compartment electrodialytic water splitter. The gas generated e.g. CO.sub.2, SO.sub.2 is released external to the water splitter where it can be easily removed by conventional techniques such as application of vacuum. The aqueous hydrogen ion-enriched solution selected must be capable of transferring hydrogen ions to the salt of the first acid in an amount sufficient to produce the first acid and a salt of the second acid; the second acid is then regenerated from the salt of the second acid.

Dependencies are inferred from the claim text.