Preliminary study on fluoride removal from contaminated groundwater by nanofiltration

In this work, a commercial nanofiltration (NF) membrane, named SPR 10113, was used for the first time to treat a real F-contaminated groundwater (F= 8.9 mg/L) coming from deep crystalline aquifer of Calabria Region (Southern Italy), in order to verify its efficiency in terms of fluorine rejection and quality of the permeate. Before treatment, a complete geochemical characterization was performed. The used membrane exhibited a fluoride rejection value ranging from 94 to 96 %, lowering the F-concentration below the limit established by WHO. Moreover, the results prove that a low ionic load was maintained in solution, producing a demineralized water not suitable for long-term drinking consumption. Nevertheless, the produced water can be also used without any further re-mineralizing process for agricultural or other purposes.