Interaction of copper with the surface of calcite

Technical Report · Tue Dec 01 00:00:00 EST 1981

DOI:https://doi.org/10.2172/5532821· OSTI ID:5532821

Franklin, M. L.; Morse, J. W.

The interaction of Cu ions in solution with the surface of calcite has been studied in a range of solutions from pure water to seawater. Observations of the uptake of Cu from solution onto calcite indicates that the process is rapid and strong in both distilled water and seawater. In distilled water, Cu uptake is directly proportional to the concentration of Cu in solution; Cu/sub s/ = K/sub s/Cu/sub 1/. The average value for K/sub s/ is 3.5 +- 1.7. The Cu/sub s/ dependence on Cu/sub 1/ is linear over the entire Cu concentration range studied (0.1 to 200 ..mu..M). Results do not indicate the formation of a precipitate of either malachite or copper carbonate. A precipitate of the form Cu/sub x/Ca/sub 1-x/CO/sub 3/ may be deposited onto the calcite surface in distilled water. The value of K/sub s/ in distilled water decreased sharply over the solid to solution ratio range of 0.1 to 2 g CaCO/sub 3/ 1/sup -1/. This was followed by a small change in K/sub s/ for solid to solution ratios in the range of 2 to 10 g CaCO/sub 3/ 1/sup -1/. In seawater, the uptake of Cu is also directly proportional to the concentration of Cu/sub 1/ up to a limiting value of approximately 13 ..mu..M. The average value for K/sub s/ in seawater, 0.24 +- 0.06 (Cu/sub 1/ less than or equal to 13 ..mu..M), is approximately an order of magnitude less than in distilled water. This is probably the result of smaller Cu/sub 1/ activity coefficients and increased site competition by other ions in seawater. Attempts to increase the Cu/sub 1/ concentration above 13 ..mu..M resulted in the additional Cu being deposited on the surface of the calcite. A possible explanation for this behavior is the formation of a precipitate of malachite on the calcite surface. The value of K/sub s/ decreased slightly with increasing solid to solution ratios in seawater.

• Research Organization: Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Miami Univ., FL (USA). Rosenstiel School of Marine and Atmospheric Sciences
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 5532821
• Report Number(s): LBL-13708; ON: DE82007923
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
54 ENVIRONMENTAL SCIENCES
14 SOLAR ENERGY
CALCITE
SORPTIVE PROPERTIES
CALCIUM CARBONATES
CHEMICAL REACTION KINETICS
COPPER
ABSORPTION SPECTROSCOPY
COPPER COMPOUNDS
ADSORPTION
CATIONS
COPPER CARBONATES
EXPERIMENTAL DATA
SEAWATER
SURFACES
WATER
WATER POLLUTION
ALKALINE EARTH METAL COMPOUNDS
CALCIUM COMPOUNDS
CARBON COMPOUNDS
CARBONATE MINERALS
CARBONATES
CHARGED PARTICLES
DATA
ELEMENTS
HYDROGEN COMPOUNDS
INFORMATION
IONS
KINETICS
METALS
MINERALS
NUMERICAL DATA
OXYGEN COMPOUNDS
POLLUTION
REACTION KINETICS
SORPTION
SPECTROSCOPY
SURFACE PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
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140400 - Solar Energy- Environmental Aspects
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