Drinking water purification using metal-organic frameworks: Removal of disinfection by-products

Water disinfection is one of the most challenging processes for public health. Nevertheless, this process can generate inorganic by-products (chlorite [ClO₂⁻] and chlorate [ClO₃⁻]) associated with human diseases. Recently, the European Union established a permissible maximum concentration of 0.25 mg⋅L⁻¹ for both oxyanions in drinking water; thus, the existing technologies have to be adapted. Here, the earliest use of metal-organic frameworks (MOFs) in the elimination of the disinfection by-products ClO₂⁻ and ClO₃⁻ from fresh water is presented. Among the Fe-MOFs proposed, the robust MIL-88B-NH₂ demonstrated exceptional oxyanions elimination capacities (100% and 30% of ClO₂⁻ and ClO₃⁻ in 1 and 5 min, respectively). Based on these results, a continuous-flow device based on MIL-88B-NH₂ was tested under simulated realistic conditions, achieving high oxyanions elimination capacities, and the reusability of the system was demonstrated. This pioneering work opens new perspectives in the implementation of MOFs in real drinking water treatment plants (DWTPs).