Concentration by Electrodialysis of L-Ascorbic acid from Wastewater Coming from the Immersion Process at a Potato Processing Plant

Abstract

The feasibility to concentrate L-ascorbic acid (Vitamin C, AsA) from wastewater coming from the immersion process at a potato processing plant by electrodialysis was evaluated. It was found that dissolved AsA could be concentrated electrically, by use of electrodialysis. The characteristics of the raw wastewater, the filtrated solution, and the electrodialyzed solutions were also assessed quantitatively. In the diluted solution after electrodialysis, biochemical oxygen demand (BOD), chemical oxygen demand (COD), total solids (TS) and volatile solids (VS) were reduced by 71.0%, 73.7%, 51.0% and 75.2%, respectively, compared to the raw wastewater. In this study, variation of dissolved AsA concentration in the concentrated solution during electrodialysis under several current densities was analyzed using a mathematical model. The calculated values by the model fit the measured values well.