The zeta potential of iron and chromium hydrous oxides during adsorption and coprecipitation of aqueous heavy metals

Journal Article · Sat Aug 10 04:00:00 EDT 1996 · Journal of Colloid and Interface Science

DOI:https://doi.org/10.1006/jcis.1996.0413· OSTI ID:367906

Crawford, R J; Harding, I H ^[1]; Mainwaring, D E ^[2]

---

1. Swinburne Univ. of Technology, Hawthorn (Australia)
2. Royal Melbourne Inst. of Tech. (Australia). Dept. of Applied Chemistry

The adsorption and coprecipitation characteristics of Cr(III), Zn(II), and Ni(II) with amorphous hydrous iron(III) oxide (HFO) and those of Zn(II) and Ni(II) with amorphous hydrous chromium(III) oxide (HCO) have been measured by the authors previously. In the current study, the zeta potentials of these colloidal substrates have been measured as a function of pH during and under the same conditions as the adsorption and coprecipitation processes. The Gouey-Chapman-Stern-Grahame model of the electrical double layer has been used, with allowance for specific site interactions, to accurately model the pH-dependent zeta potential for the individual hydrous metal oxides involved. A surface site mixing model has been proposed which models the zeta potential of the oxide substrates in the presence of an increasing amount of a dissimilar second oxide surface, which results from the process of metal ion adsorption or coprecipitation. This mixing model was found to satisfactorily account for all trends observed in the zeta potentials measured during the adsorption and coprecipitation of Cr(III), Zn(II), and Ni(II) with HFO and those of Zn(II) and Ni(II) with HCO.

• OSTI ID: 367906
• Journal Information: Journal of Colloid and Interface Science, Journal Name: Journal of Colloid and Interface Science Journal Issue: 2 Vol. 181; ISSN 0021-9797; ISSN JCISA5
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
ADSORPTION
CHROMIUM
CHROMIUM OXIDES
COLLOIDS
COPRECIPITATION
HYDRATES
IRON OXIDES
MATHEMATICAL MODELS
METALS
NICKEL
PH VALUE
SURFACE POTENTIAL
SURFACE WATERS
WASTE WATER
WATER TREATMENT
ZINC