Municipal wastewater effluent is a source of emerging pollutants including pharmaceuticals, personal care products, and agricultural chemicals. Metal-organic frameworks (MOFs) can be used as sorbents to remove pollutants from wastewaters owing to their large surface areas and tuneability. However, before being used for pollutant removal, MOF stability in aqueous environments under application conditions must be fully evaluated to understand how MOFs (whether pristine or composites) affect the water matrix and vice versa. Current knowledge of MOF stability in deionised water under application-relevant conditions and in wastewater effluent is limited. Detailed investigations into aqueous MOF stability are crucial if they are to move up the technology readiness levels to be used in practice as a wastewater treatment technology. In this work, pristine MIL-100(Fe) was immersed in deionised water and its structural stability was evaluated as a function of time, water temperature, and quantity of MOF. MIL-100(Fe) is stable in aqueous conditions for up to 28 days and up to a temperature of 30 °C. For the first time, pH is monitored throughout stability experiments. An immediate decrease in pH (from 5.6 ± 0.5 to 3.2 ± 0.3) is observed upon immersion of MIL-100(Fe) in deionised water. Comparatively, when MIL-100(Fe) is immersed in wastewater effluent, a buffering effect is observed. This study uses fundamental scientific observations to provide key considerations, which will inform on the use and suitability of MIL-100(Fe) as a sorbent for wastewater treatment.
CORE (COnnecting REpositories)
CORE (COnnecting REpositories)