Transforming salty whey into cleaning chemicals using electrodialysis with bipolar membranes

Abstract

Large quantities of salty whey are produced during cheese manufacturing, posing an environmental problem. Here the feasibility of electrodialysis with bipolar membranes (EDBM) is evaluated for the first time as a mechanism to transform this saline effluent into sodium hydroxide and hydrochloric acid for reuse within the factory. This work also seeks to find the maximum acid and base concentration that can be achieved. For a pure sodium chloride solution, maximum acid/base concentrations of 3.6 ± 0.2 mol/L and 3.0 ± 0.3 mol/L are achieved using a stack of ten membranes including four bipolar membranes. The effects of proton leakage and water migration limit the generation of higher concentrat..