Self-assembled cylindrical Zr (IV), Fe (III) and Cu (II) impregnated polyvinyl alcohol-based hydrogel beads for real-time application in fluoride removal

Efficient Fluoride Removal by a Fixed-Bed Column of Self-Assembled Zr(IV)-, Fe(III)-, Cu(II)-Complexed Polyvinyl Alcohol Hydrogel Beads

“… 7 , 18 , 51 Moreover, the metal ions are bound to the PVA matrix, which prevents secondary contamination of the treated water ( Table 1 ). 18 The fixed-bed column of bio-based adsorbents have shown good fluoride removal efficiency from solutions containing higher initial fluoride concentrations. These adsorbents remove fluoride effectively at a greater flow rate.…”

“…The evidence of chemisorption of fluoride by the hydrogel beads is confirmed by thermodynamic calculations of batch adsorption studies ( Table 1 ). 18 This is also reinforced by the Fourier transform infrared (FT-IR) spectral analysis of the hydrogel beads. The spectra of hydrogel beads are obtained using a FT-IR spectrophotometer (Spectrum 2, PerkinElmer, USA).…”

“…The hydrogel beads are washed and subjected to freeze–thaw cycles. 18 Finally, the polymer hydrogel beads are dried at 90 ± 2 °C and used for column adsorption studies.…”

“…As the hydrogels exhibit pH-independent behavior in a wide pH range (3.0 ± 0.2–9.0 ± 0.2), the column adsorption is carried out with a fluoride solution of pH 6.5 ± 0.2 ( Table 1 ). 18 The groundwater fluoride concentration is generally found to be ≤10 ± 0.20 mg L –1 in India. 1 , 2 , 4 Hence, for fixed-bed column adsorption, the influent fluoride concentration ( C 0 ) is maintained at 10 ± 0.20 mg L –1 , and all the studies are conducted at 25 °C.…”

“…To overcome these challenges, self-assembled zirconium (PZH)-, iron–zirconium (PFZH)-, and copper–zirconium (PCZH)-complexed PVA hydrogel beads are synthesized, which have good regenerability, wide pH applicability, and good selectivity for fluoride even for groundwater samples. 18 In the current study, the fluoride adsorption efficiency by the fixed-bed column of cylindrical metal–PVA hydrogel beads is explored by experimental techniques. In addition, mathematical modeling of the breakthrough curve is done to obtain the parameters for fixed-bed column adsorption.…”