The separation of acids from metallic cations is now possible thanks to the development of selective cation exchange membranes. In metallurgy, membranes processes can be used for the recovery and the purification of pickling and water rinsing bath and for the treatment of electroplating solutions for example. The hydrogen fluoride electrodialysis is now efficient to treat waste water from glass and crystal manufactures. These are used in the acid or alkali solution production. Those fluids are present in various industries and promise an important development of bipolar membrane in the future.
Some metallurgical applications begin to appear in United States.
In Europe, BPM begins to be used for the conversion of organic salts produced by bio-fermentation. The salt solution is extracted in continue from the fermentor and is acidified after ultra filtration, in a compartment of the bipolar reactor. In an other compartment, sodium hydroxide is produced and is sent to the fermentor to stabilised the pH of the fermentation. The conventional and BPM electrodialysis are thus a more and more efficient technology to treat waste water of different industries and to recover acid or expensive metallic cation. You can find some WWW sites dedicated to separation techniques, membrane technologies and micelles studies.