Cobalt, cadmium, and lead sorption to hydrous iron oxide: Residence time effect

Journal Article · · Soil Science Society of America Journal; (United States)

DOI:https://doi.org/10.2136/sssaj1994.03615995005800060005x· OSTI ID:6707306

Ainsworth, C C; Gassman, P L ^[1]; Pilon, J L; Van Der Sluys, W G ^[2]

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1. Pacific Northwest Lab., Richland, WA (United States)
2. Univ. of Montana, Missoula, MT (United States)

The adsorption-desorption of the divalent metal cations (Me[sup 2+]) Co[sup 2+], Cd[sup 2+], and Pb[sup 2+] to hydrous ferric oxide (HFO) was investigated as a function of oxide aging and Me[sup 2+]-oxide residence time. The HFO was produced and stored for up to 86 wk. Periodically, Me[sup 2+] sorption was determined across the pH range of 2.5 to 12. In addition, the Me[sup 2+] ions were contacted with freshly produced HFO and stored at a pH that dictated that 80 to 100% of the Me[sup 2+] would be in the sorbed state; desorbability of the Me[sup 2+] was determined as a function of Me[sup 2+]-oxide residence time. The change in the crystallinity of the HFO as a function of time was also monitored. The HFO aged without the Me[sup 2+] ions displayed no hysteresis between the adsorption-desorption curves and no substantial shifts in fractional Me[sup 2+] adsorption were observed with pH throughout 21 wk of aging. The HFO aged with the Me[sup 2+] ions displayed increasing desorption hysteresis with time for Co[sup 2+] and Cd[sup 2+], but not Pb[sup 2+]. The magnitude of hysteresis followed the order Co > Cd > Pb, which is the inverse of the ionic radii of the metal sorbates. While oxalate-extractable Fe decreased with time during a 20-wk period, powder x-ray diffraction was unchanged during the same period. 38 refs., 11 figs., 2 tabs.

• DOE Contract Number: AC06-76RL01830
• OSTI ID: 6707306
• Journal Information: Soil Science Society of America Journal; (United States), Journal Name: Soil Science Society of America Journal; (United States) Vol. 58:6; ISSN 0361-5995; ISSN SSSJD4
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400102 -- Chemical & Spectral Procedures
400201 -- Chemical & Physicochemical Properties
54 ENVIRONMENTAL SCIENCES
540220* -- Environment
Terrestrial-- Chemicals Monitoring & Transport-- (1990-)
ADSORPTION
AGING
CADMIUM COMPOUNDS
CHALCOGENIDES
COBALT COMPOUNDS
COHERENT SCATTERING
COMPILED DATA
CRYSTAL STRUCTURE
DATA
DESORPTION
DIFFRACTION
HYSTERESIS
INFORMATION
IRON COMPOUNDS
IRON OXIDES
LEAD COMPOUNDS
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PH VALUE
SCATTERING
SORPTION
SORPTIVE PROPERTIES
SURFACE PROPERTIES
TRANSITION ELEMENT COMPOUNDS
X-RAY DIFFRACTION