Hydrofluoric acid and sodium hydroxide production by bipolar membrane electrodialysis

Abstract

AbstractThe purpose of this study was to offer an alternative new eco-friendly and easily implemented process for the production of hydrofluoric acid and sodium hydroxide. The production of hydrofluoric acid and sodium hydroxide from sodium fluoride was carried out by bipolar membranes electrodialysis. The process feasibility was tested using a laboratory electrodialysis cell. The behavior of the process was investigated for 0.05, 0.025 M concentration and 5, 7.5, 10 V potential. In conclusion, the current efficiencies were obtained up to a value of 98.51 at the applied potential of 10 V and 0.05 M, and the purities were found to be 99.7% and as 99.1% for hydrofluoric acid and sodium hydroxide, respectively. These high purities of acid and base were obtained without any harmful waste material or side product. When in terms of both production technique and environmental impact were compared to hydrofluoric acid production by the reaction of acid-grade fluorspar (CaF2) with sulfuric acid (H2SO4) and sodium ...