Electrodeionization for the Bio-Succinic Acid Production Process

Abstract

The production of succinic acid is of great importance due to the growing use of this compound in the industry. Biotechnological conversion requires the separation and purification of the main product. In the case of carboxylic acids, an additional problem is the alkaline environment of the subculture of microorganisms and, consequently, the need to convert the carboxylate formed into the free acid form of the product. Methods such as extraction or esterification do not separate the carboxylate. Acidification of fermentation broths with inorganic acids generates large fractions of waste. This is not only inconsistent with the principles of sustainable technology but also increases the cost of the process. Succinate conversion is possible through ion exchange or electrodialysis. However, these methods have limitations and drawbacks that reduce the efficiency of the process. A potential solution to these limitations is the application of applying electrodeionization (EDI) as a downstream stage in the technology of the bioproduction of carboxylic acids. Aqueous solutions of disodium succinate (pH 6.8) were converted into the electrodeionization module. In the final product of succinic acid, the residual sodium was determined at a level of 4% (conversion efficiency 96%). This paper presents preliminary research showing the possibility of applying electrodeionization of sodium succinate on an EDI module consisting of cation-exchange membranes and an ion-exchange resin. The results obtained are the basis for further research on this issue.