Bipolar membrane is a new type of composite ion exchange membrane, which usually consists of an anion exchange layer, a cation exchange layer and an intermediate layer between the two membrane layers. Under the action of the DC electric field, the water molecules in the intermediate layer can be efficiently dissociated into hydrogen ions (H+) and hydroxide radicals (OH-), thereby realizing the conversion of salts into corresponding acids and bases.
Remarks: The above data are reference values, not the performance guarantee values of the ion exchange membrane, and the data in the table may change.
(1) Organic acid production: In the process of organic acid production, it is necessary to convert organic acid salts into organic acids; the traditional method adopts ion exchange, and the regeneration process of ion exchange column consumes a large amount of acid and generate a large amount of salty wastewater; bipolar membrane water dissociation generates H+ and OH-, thus organic acid is produced directly without adding acid and alkali is produced as the by-product, which simplifies the process and avoids environmental pollution.
(2) Food and pharmaceutical industry: The acid and alkali generated by the water dissociation in bipolar membrane electrodialysis are used for the on-line adjustment of pH value in the production process of food and pharmaceutical industry, without the need for external acid and alkali and without the introduction of foreign ingredients.
(3) Environmental protection: As a new membrane separation process, bipolar membrane electrodialysis water dissociation can convert salts in aqueous solutions into the corresponding acids and bases without introducing new components, which can provide a new way for the regeneration and recovery of certain material resources, reducing waste discharge and eliminating environmental pollution.