Metal in rivers

Rhodium occurs native with other platinum metals in river sands of the Urals and in North and South America. It is also found with other platinum metals in the copper-nickel sulfide area of the Sudbury, Ontario region. Although the quantity occurring here is very small, the large tonnages of nickel processed make the recovery commercially feasible. The annual world production of rhodium is only 7 or 8 tons. 

Thomas, R. R, Ure, A. M., Davidson, C. M., Littlejohn, D., Rauret, G., Rubio, R., and Lopez-Sanchez, J. F., Three-Stage Sequential Extraction Procedure for the Determination of Metal in River Sediments, Analytica Chimica Acta 286, 1994, 423 29. 

Kopp JF, Kroner RC. 1970. Trace metals in waters of the United States. A five year summary of trace metals in rivers and lakes of the United States (Oct. 1, 1962- Sept. 30, 1967). Cincinnati, OH US Department of the Interior, Federal Water Pollution Control Administration, Division of Pollution Surveillance. 

Lu JY, Chakrabarti CL, Back MH, et al. 1996. Speciation of some metals in river surface water, rain and snow, and the interactions of these metals with selected soil matrices. J Anal Atom Spectrom 11 1189-1201. 

Example Multivariate cross-correlation for the computation of transport rates of dissolved metals in river water... 

Speciation of Heavy Metals in River Water Investigated by Chemometric Methods... 

Factor Analysis of the Total Concentrations of Heavy Metals in River Sediments... 

In rivers and streams heavy metals are distributed between the water, colloidal material, suspended matter, and the sedimented phases. The assessment of the mechanisms of deposition and remobilization of heavy metals into and from the sediment is one task for research on the behavior of metals in river systems [IRGOLIC and MARTELL, 1985]. It was hitherto, usual to calculate enrichment factors, for instance the geoaccumulation index for sediments [MULLER, 1979 1981], to compare the properties of elements. Distribution coefficients of the metal in water and in sediment fractions were calculated for some rivers to find general aspects of the enrichment behavior of metals [FOR-STNER and MULLER, 1974]. In-situ analyses or laboratory experiments with natural material in combination with speciation techniques are another means of investigation [LANDNER, 1987 CALMANO et al., 1992], Such experiments manifest univariate dependencies for the metals and other components, for instance between different metals and nitrilotriacetic acid [FORSTNER and SALOMONS, 1991], but the interactions in natural systems are often more complex. 

Not only are accurate data for trace metals in rivers sparse, there are complications that exist at the river-sea interface. The increase in salinity occurring at the river-sea water interface, with its concomitant increase in the concentrations of the major seawater cations, can lead to flocculation and sedimentation of trace metals such as iron (Boyle et al., 1978 Sholkovitz and Copeland, 1983) or to desorption from suspended riverine particles of trace metals such as barium (Edmond et al., 1978). In organic-rich rivers a major fraction of dissolved trace metals can exist in physiochemical association with colloidal humic acids. Sholkovitz and Copeland (1983) used product-mode mixing experiments on filtered Scottish river water, and observed that iron removal was almost complete due to the flocculation of strongly associated iron-humic acid colloids in the presence of the increased... 

REGULATION OF DISSOLVED HEAVY METALS IN RIVERS, LAKES, AND OCEANS... 

Regulation of Dissolved Heavy Metals in Rivers, Lakes, and Oceans 655... 

The role of settling particles in regulating the concentrations of heavy metals in rivers, lakes, and oceans has been discussed in Chapter 10. 

Salomons, W., Eysink, W., In "Biogeochemical and Hydrodynamic Processes Affecting Heavy Metals in Rivers, Lakes and Estuaries". Delft Hydraulics Laboratory Publication No. 253 Delft 1981, The Netherlands. 

References to 3.5 "Solid Speciation of Metals in River Sediments"... 

Whitton, B. A., Use of plants to monitor heavy metals in rivers. In Biomonitoring of Environmental Pollution, Yasuno, M. and Whitton, B. A., Eds., Tokai University Press, Tokyo, 1988. 

Reus U, Markeit B, Hoffmeister C, Spott D, Guhr H (1993) Determination of trace metals in river water and suspended solids by TXRF spectroscopy A methodical study on analytical performance and sample homgeneity. Fresenius J Anal Chem 347 430-435 Sanchez HJ. (2001) Detection limit calculations for the total reflection techniques of X-ray fluorescence analysis. Spectrochimica Acta 56 2027-2036... 

Reus, U., Markert, B., Holfmeister, C., Spott, D., Guhr, H., 1993. Determination of trace metals in river water and suspended soils by TXRF spectrometry. Fresenius Z. Anal. Chem. 347, 430-435. 

Dissolved and particulate metals in rivers and estuaries are derived from natural weathering process in the catchment area, and reflect the geological composition of the watershed (see Table 1 for the crustal abundance of selected metals) and the local climatic conditions. Natural concentrations of metals can be augmented in catchment areas that are mineralized, and there may be a significant anthropogenic perturbation downstream because of mineral extraction... 

Wilson, A. L. Concentration of Trace Metals in River Waters A Review, ... 

Smith R. 1984. NIWR interlaboratory comparison study No. 83/A Determination of trace metals in river sediment. Pretoria, South Africa Council for Scientific and Industrial Research, National Institute for Water Research. Research report No. 602, 1-33. 

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