Adsorption parameters of Cd(II), Pb(II), and Hg(II) on zirconium(IV) phosphate chemically grafted onto silica gel surface

Journal Article · Wed Apr 01 04:00:00 EST 1998 · Journal of Colloid and Interface Science

DOI:https://doi.org/10.1006/jcis.1997.5344· OSTI ID:616332

Nagata, Noemi; Kubota, L T; Bueno, M I.M.S.; Peralta-Zamora, P G ^[1]

---

1. Univ. Estadual de Campinas, Sao Paulo (Brazil). Inst. de Quimica

Adsorption properties of metallic ions not essential for human metabolism, such as cadmium, lead, and mercury, on silica chemically modified with zirconium(IV) phosphate, SiZrP, were investigated using batch systems. The immobilization procedure was efficient and the functionalization degree was 2.82% for zirconium (0.31 mol/g) and 2.54% for PO{sub 4}{sup 3{minus}} (0.27 mol/g). These results indicate that phosphate reacted with zirconium in a 1:1 ratio. The equilibrium is reached very quickly (15 min.), indicating that the adsorption sites are well exposed. The best adsorption parameters were evaluated using 50 mL of aqueous phase at pH 4.5, an adsorption time of 15 min, and 0.2000 g of adsorbent. From adsorption isotherms obtained for the metals ions and distribution coefficients the affinity of SiZrP for the metal ions studied increases in the order Cd(II) < Pb(II) < Hg(II). Twice as much lead was adsorbed by the SiZrP surface (Nf = 10.0 {micro}mol/g) as cadmium (Nf = 5.0 {micro}mol/g). For mercury, the capacity was greater; nevertheless an adsorption plateau was not observed.

• OSTI ID: 616332
• Journal Information: Journal of Colloid and Interface Science, Journal Name: Journal of Colloid and Interface Science Journal Issue: 1 Vol. 200; ISSN 0021-9797; ISSN JCISA5
• Country of Publication: United States
• Language: English

Related Subjects

40 CHEMISTRY
ADSORPTION
ADSORPTION ISOTHERMS
CADMIUM
ION EXCHANGE MATERIALS
LEAD
MERCURY
SILICA GEL
SORPTIVE PROPERTIES
ZIRCONIUM PHOSPHATES