Sorption of cadmium and copper from an acid mine waste extract by two calcareous soils: Column studies

Journal Article · Fri Feb 01 04:00:00 EST 1991 · Soil Science; (United States)

DOI:https://doi.org/10.1097/00010694-199102000-00002· OSTI ID:5598734

Dudley, L M; McLean, J E; Furst, T H; Jurinak, J J ^[1]

---

1. Utah State Univ., Logan (USA)

The authors previous findings suggested different Cu and Cd retention mechanisms for each of two calcareous soils. Solubility data indicated that the Skumpah soil (30% CaCO{sub 3}) reacted with the water extract of an acid mine waste to form tenorite (CuO). Batch desorption of the waste-extract equilibrated Kidman soil (0.2% CaCO{sub 3}) with CaCl{sub 2} indicated that cation exchange was the metal retention mechanism. This study tested these hypotheses of metal retention mechanisms in soil columns. Scanning electron microscopy, back scattering electron microscopy, and x-ray diffraction (XRD) were used to investigate the distribution and forms of Cu in the Skumpah soil that had been leached with waste extracts. Leaching with the mine waste reduced the intensity of calcite and dolomite peaks in diffractograms of soil samples from the upper 8 cm of the columns. Copper and Cd retention in the Kidman soil was investigated via a transport model in which cation exchange was assumed to be the mechanism of metal interaction with the solid phase. Model predictions were compared (1) to metal breakthrough curves for the acid leachate, and (2) to metal release curves obtained by leaching the columns with CaCl{sub 2} after metal breakthrough. The model failed to predict Cd breakthrough portions of the curves satisfactorily but was in agreement with the CaCl{sub 2} leaching curves for all metals. Results of the modeling study indicated that the composition of the leaching solution and exchange phase determined the degree of uncertainty that could be tolerated in the values of the selectivity coefficients. Further, it appeared that exchange reactions controlled metal retention and transport at acid pH.

• OSTI ID: 5598734
• Journal Information: Soil Science; (United States), Journal Name: Soil Science; (United States) Vol. 151:2; ISSN SOSCA; ISSN 0038-075X
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540210* -- Environment
Terrestrial-- Basic Studies-- (1990-)
ACID MINE DRAINAGE
ALKALINE EARTH METAL COMPOUNDS
CADMIUM
CALCIUM CARBONATES
CALCIUM COMPOUNDS
CARBON COMPOUNDS
CARBONATES
CHEMISTRY
COHERENT SCATTERING
COPPER
DIFFRACTION
DISPERSIONS
ELECTRON MICROSCOPY
ELEMENTS
LEACHATES
MANAGEMENT
MATHEMATICAL MODELS
METALS
MICROSCOPY
MIXTURES
OXYGEN COMPOUNDS
PH VALUE
PROCESSING
SCATTERING
SOIL CHEMISTRY
SOLUTIONS
SORPTIVE PROPERTIES
SURFACE PROPERTIES
TRANSITION ELEMENTS
WASTE MANAGEMENT
WASTE PROCESSING
X-RAY DIFFRACTION