Solubility, metals

Some metals are soluble as atomic species in molten silicates, the most quantitative studies having been made with Ca0-Si02-Al203(37, 26, 27 mole per cent respectively). The results at 1800 K gave solubilities of 0.055, 0.16, 0.001 and 0.101 for the pure metals Cu, Ag, Au and Pb. When these metal solubilities were compared for metal alloys which produced 1 mm Hg pressure of each of these elements at this temperature, it was found drat the solubility decreases as the atomic radius increases, i.e. when die difference in vapour pressure of die pure metals is removed by alloy formation. If the solution was subjected to a temperature cycle of about 20 K around the control temperamre, the copper solution precipitated copper particles which grew with time. Thus the liquid metal drops, once precipitated, remained stable thereafter. 

Non-metallic impurities in liquid alkali metals play a major role in the corrosion of materials either by affecting metal solubilities, f orming spalli-ble corrosion products on the metal surface, promoting liquid metal embrittlement or bulk embrittlement of the surface or by sensitising the structure for further attack by other impurities e.g. O2. As in other corrosive environments the direction and magnitude of these impurity reactions... 

The present survey will be confined to corrosion arising as a result of oxidation of the metal to ions, since little information on corrosion involving only metal-solubility effects is available. 

An evaluation of the fate of trace metals in surface and sub-surface waters requires more detailed consideration of complexation, adsorption, coagulation, oxidation-reduction, and biological interactions. These processes can affect metals, solubility, toxicity, availability, physical transport, and corrosion potential. As a result of a need to describe the complex interactions involved in these situations, various models have been developed to address a number of specific situations. These are called equilibrium or speciation models because the user is provided (model output) with the distribution of various species. 

McBride. Reactions controlling heavy metal solubility in soils. Adv. Soil Sci 1989 10 1-56. 

McGowen S.L., Basta N.T., Brown G.O. Use of diammonium phosphate to reduce heavy metal solubility and transport in smelter-contaminated soil. J Environ Qual 2001 30 493-500. 

Rubisov, D. H. Papangelakis, V. G. Sulfuric acid pressure leaching of laterites—prediction of metal solubilities and speciation analysis at temperature. EPD Congress 1999, Proceedings of Sessions and Symposia held at the TMS Annual Meeting, San Diego, Feb. 28-Mar. 4, 1999, 535-546. 

Effluents emerging from sulfide-rich waste-dumps have special characteristics, such as very low pH (< 4), high metal solubility and presence of iron colloids, which provokes water turbidity and precipitation of ochre-products. These effluents are generically named acid mine drainage (AMD), since they result, primarily, from mineral-water interactions involving some sulfide minerals that typically produce acidity upon oxidative dissolution. 

Complex metallocyanides Excess CN" in the presence of metals solubilities of metallocyanides vary Callahan et al. 1979 EPA 1992f... 

Stevenson [99] conducted the first polycondensation experiments with thin polymer melt films of 0.07-5 mm thickness. The experiments were performed on metal surfaces at temperatures between 265 and 285 °C under vacuum. He varied the kind of metal and observed that the behaviour of the polycondensation rate with decreasing film thickness depended on the metal being used. He concluded that the reaction rate increased only on metals soluble in the polymerizing melts... 

While investigating the properties of low melting metals, a specific aspect of the alloying behaviour of Bi has been studied by Guminski (1989, 1990) who compiled and discussed the data concerning the solubility of the different elements in this metal. Solubility data at 600°C have been plotted and discussed as a function of the atomic number curves showing periodic variations were obtained with trends very similar to those obtained for Hg, Ga, In, Sn and Pb (with very deep minima, for instance, for the elements in positions close to Mo and W). 

Speciation of transition metals by natural organic substances that behave as complexing ligands may occur in the subsurface following waste and sludge disposal. As a result, metal solubility increases, favoring metal mobility with depth. 

Changes in metal solubility with respect to physico-chemical parameters controlling solubility ... 

Martinez, C.E. McBride, M.B. (1998) Coprecipitates of Cd, Cu, Pb and Zn in iron oxides solid phase transformation and metal solubility after aging and thermal treatment. Clays Clay Min. 46 537-545... 

Kempton S, Sterrit RM, Lester JN. 1987. Heavy metal removal in primary sedimentation. I. The influence of metal solubility. Sci Total Environ 63 231-247. 

These elements exist in a variety of forms and concentrations. Metal complexes with asphaltenes, porphyrins, and other polar organics can stabilize metal solubility throughout the crude oil matrix. Concentrations of metals can range from <1 to 1500 ppm or more. 

Metals Soluble in Nitric Acid. — Strongly ignite 2 gm. of platinic chloride. A residue of platinum sponge weighing 0.752 gm. should be obtained. Digest this residue with dilute nitric acid (5 cc. of nitric acid and 20 cc. of water) on the water-bath for fifteen minutes, then filter, evaporate the filtrate on the water-bath, and ignite the residue so obtained. The weight of the latter should not exceed 0.005 gm. 

Again, we deal with the simple redox reaction 0 + ne = R. In the present discussion we suppose that 0 is a metal ion and R is the corresponding metal soluble as an amalgam in a mercury electrode or present as the pure metal electrode. It is highly probable that 0 forms several complexes e.g. with the anions of the supporting electrolyte, additives like NH3, EDTA, etc. or OH" ions. For the sake of simplicity, we confine ourselves here to considering the equilibrium between hydrated 0 and only one complex... 

Magnesium chloride, anhydrous, 29 Manganous chloride, anhydrous, 29 Mercuric sulfide, red, 19 Mercury, solubility of metals in, 6 Metals, solubility in mercury, 6 Monochloroamine, 59 analysis of, 62... 

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