CORDIS OpenAire Sygma Archivio istituzionale della ricerca - Università di Cagliari Crossref Microsoft Academic Graph European Union Open Data Portal https://iris.unica.it/bitstream/11584/272227/1/JWPE_2019.pdf https://doi.org/10.1016/j.jwpe.2019.100855 Journal of Water Process Engineering Open Access 2019-05-18 2019-07-09 Abstract Health risks linked to the regular consumption of water with high fluoride (F−) content seriously affect rural areas of the East African Rift Valley. The F− removal capacity has been tested on uncalcined and calcined carbonate layered double hydroxides (LDHs), with different cationic compositions (M2+ = Mg2+, Zn2+; M3+ = Al3+, Fe3+) and M2+/M3+ molar ratio (2, 3, 4), taking into account the necessity of a simple defluoridation method. The 3MgAlFe-cal phase derived from calcination of a hydrotalcite-like compound with composition Mg/(Al + Fe) = 3/(0.5 + 0.5) results to be the best F− remover (43 mg/g) and can uptake up to 92.3 mg/g when the interlayer is fully saturated with F−. At the high pH reached during the experiments (up to pH 12 for calcined LDHs), the presence of carbonate species in solution significantly affects the F− removal capacity. The recyclability of the sorbent was tested by regeneration through calcination of the 3MgAlFe-cal phase: under F− unsaturated interlayer conditions, up to 80% of the starting F− removal capacity is still preserved after four regeneration cycles, indicating that LDHs can be reused after regeneration and have a potential use in water defluoridation. fluoride-rich water; layered double hydroxides; regeneration; removal capacity; water defluoridation 02 engineering and technology 0210 nano-technology 01 natural sciences 6. Clean water 0105 earth and related environmental sciences Dore E., Frau F., 2019-10-01 journalpaper Abstract Health risks linked to the regular consumption of water with high fluoride (F−) content seriously affect rural areas of the East African Rift Valley. The F− removal capacity has been tested on uncalcined and calcined carbonate layered double hydroxides (LDHs), with different cationic compositions (M2+ = Mg2+, Zn2+; M3+ = Al3+, Fe3+) and M2+/M3+ molar ratio (2, 3, 4), taking into account the necessity of a simple defluoridation method. The 3MgAlFe-cal phase derived from calcination of a hydrotalcite-like compound with composition Mg/(Al + Fe) = 3/(0.5 + 0.5) results to be the best F− remover (43 mg/g) and can uptake up to 92.3 mg/g when the interlayer is fully saturated with F−. At the high pH reached during the experiments (up to pH 12 for calcined LDHs), the presence of carbonate species in solution significantly affects the F− removal capacity. The recyclability of the sorbent was tested by regeneration through calcination of the 3MgAlFe-cal phase: under F− unsaturated interlayer conditions, up to 80% of the starting F− removal capacity is still preserved after four regeneration cycles, indicating that LDHs can be reused after regeneration and have a potential use in water defluoridation. Calcined and uncalcined carbonate layered double hydroxides for possible water defluoridation in rural communities of the East African Rift Valley 10.1016/j.jwpe.2019.100855