Preparation of mixed rare earths modified chitosan for fluoride adsorption

Towards the implementation of an ion-exchange system for recovery of fluoride commodity chemicals. Kinetic and dynamic studies

“…For uptake from NaF solution, the calculated rate constants were considerably higher than previously reported for metal-loaded resins at comparable Ci values [53,54] and for other rare-earth-functionalised sorbents [22,24]. This may be partially attributed to the large accessible surface area of the macroporous resin.…”

“…Several studies have also used the more economical lanthanides (La and Ce) for sorbent modification for fluoride selectivity. Modified materials include ion-exchange resins [21], alumina [22,23] and chitosan [24,25].…”

A Review of Fluoride Removal from Groundwater

“…At an adsorbent dose of 2 g / lit, the fluoride adsorption is maximum at pH 7 and reaches equilibrium in 60 min time. Rare earth modified chitosan for defluoridation purposes have been used by Liang et al [71]. The effect of various parameters such as initial fluoride concentration contact time, effect of co-ions and adsorbent dose have been studied.…”

A Review on Adsorption of Fluoride from Aqueous Solution

“…These include activated carbons [81,82,83,84,85,86], activated alumina [87,88,89,90], bauxite [89,91,92,93,94,95,96,97,98,99,100,101,102], hematite [95,103,104,105], polymeric resins [67,96,97,106], activated rice husk [83,98,99,107], brick powder [100], pumice stone [101,108,109], red soil, charcoal, brick, fly ash, serpentine [102,110,111], seed extracts of Moringa oleifera [98], granular ceramics [112], chitin, chitosan and alginate [95,113,114,115,116,117,118,119], modified ferric oxide/hydroxide [120,121,122,123,124,125,126], hydroxyapatite (HAP) [106,107,127,…”