Fluoride adsorption studies on mixed-phase nano iron oxides prepared by surfactant mediation-precipitation technique

Abstract

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A Comparative Study on Removal of Hazardous Anions from Water by Adsorption: A Review

“…Most of the FTIR studies on fluoride removal by different adsorbents have shown the involvement and the participation of the surface sites and potential functional groups in the adsorption, especially the hydroxyl group [138,139]. It was observed that fluoride interacts with the OH and NH groups on surface aluminum-impregnated coconut fiber surface [140].…”

Defluoridation with Locally Produced Thai Bone Char

“…However, sulfate and phosphate ions were found to compete with fluoride sorption on materials with iron and aluminum bases [13]. Chloride and sulfate interfered with fluoride removal by mixed-phase nano iron oxides [30]. All these experiments on the influence of other ions on sorption were done with synthetic fluoride solutions mixed with only single ion.…”

CTAB mediated Mg-doped nano Fe2O3: synthesis, characterization, and fluoride adsorption behavior

“…A comparison of chemical analysis and phase formation of various samples obtained by precipitation of iron oxides/hydroxides using similar conditions (i) in the absence of CTAB and magnesium [42], (ii) in the presence of CTAB [21], and (iii) in the presence of both CTAB as well as magnesium are given in Table 1.…”

“…When precipitation was carried out by CTAB mediation in the absence of Mg(II) ions, mixed phases of iron oxides containing ferrihydrite, goethite, and hematite were obtained. Detailed studies on fluoride adsorption on the mixed oxides so obtained have been published [21] and will be compared in later section. It is only on surfactant mediation doping of Mg(II) ion hematite phase was formed.…”

“…Water purification technologies based on nano materials are gaining tremendous importance [14][15][16][17]. Some studies have been reported on synthesis of pure and doped nano iron oxides/ hydroxides-based materials and their adsorption behavior for fluoride [18][19][20][21]. Recently, several studies have been reported on the synthesis of hematite particles following different routes, which include micro emulsion [22], surfactant assisted hydrothermal [23], solvothermal [24], and precipitation methods using different combinations of reagents [25].…”