Sorption of Antimony onto Hydroxyapatite

• Published in: Environmental science & technology 2001-09, Vol.35 (18), p.3669-3675
• Main Authors: Leyva, Ana G, Marrero, Julieta, Smichowski, Patricia, Cicerone, Daniel
• Format: Article
• Language: English
• Subjects: Adsorption; Antimony - chemistry; Applied sciences; Biological and physicochemical phenomena; Durapatite - chemistry; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Exact sciences and technology; Freshwater; Hydrogen-Ion Concentration; hydroxyapatite; Microscopy, Electron, Scanning; Models, Theoretical; Natural water pollution; Pollution; Pollution, environment geology; Thermodynamics; Water Pollution - prevention & control; Water Purification - methods; Water treatment and pollution; X-Ray Diffraction
• ISSN: 0013-936X; 1520-5851
• DOI: 10.1021/es0009929

We prepared synthetic hydroxyapatite [HAP; Ca5(PO4)3 - x (CO3) x (OH)1+ x (x = 0.3)] and then investigated this material's ability to remove trivalent antimony [Sb(III)] from water. The HAP was characterized by X-ray diffraction analysis, scanning electron microscopy, X-ray energy dispersive spectroscopy, X-ray photoelectron spectroscopy, and infrared spectroscopy. The sorption of Sb(III) to HAP was measured over an Sb(III) concentration range of 0.05−50 mg L-1, at constant ionic strength (I = 0.01 mol dm-3) in equilibrated aqueous suspensions (34 g dm-3) for 5 < pH < 8 in vessels that were closed to the atmosphere. Under these conditions, we found that HAP particles were enriched in Ca after incongruent dissolution of the solid. More than 95% of the Sb(III) in solution adsorbed to the solid-phase HAP in