Vanadium in water

In this work ion-exchange and gel-permeation chromatography coupled with membrane filtration, photochemical oxidation of organic metal complexes and CL detection were applied to the study of the speciation of cobalt, copper, iron and vanadium in water from the Dnieper reservoirs and some rivers of Ukraine. The role of various groups of organic matters in the complexation of metals is established. 

So far as is known, there is no biological component in the processes which lead to the formation of deposits such as Yeelirrie in ceilcrete (Dall Ag-lio et al., 1974). In such deposits the uranium is present in uranyl compounds, the precipitation of which appears to depend on the solubility relationships of uranyl and other ions, including complexes containing vanadium, in waters of varying composition carbonate concentration appears to have been especially important. 

GFAAS and FAAS are the techniques (Methods 7911 and 7910) recommended by EPA s Office of Solid Waste and Emergency Response for measuring low levels of vanadium in water and waste water (EPA 1986a). Detection limits of 4 jg of vanadium/L of sample and 200 jg of vanadium/L of sample were achieved using GFAAS and FAAS techniques, respectively. Spectrophotometry has also been employed to measure ppm levels of vanadium in aqueous media (Abbasi 1981 Jha 1979). 

Abbasi SA. 1981. Pollution due to vanadium and a new spot test for detection of traces of vanadium in water, plants, soils, and rocks. Intern J Environ Stud 18 51-52. 

N. Teshima, S. Ohno, T. Sakai, Stopped-in-loop flow analysis of trace vanadium in water, Anal. Sci. 23 (2007) 1. 

The concentrations of vanadium in water depend largely on geographical location and may range from about 0.2 to more than 100 fig/L In drinking water supplies in the United States, 91% of sampies analyzed had below 10 fig/L, and the average was 4.3, g/L. However, typical values in drinking water appear to be about 1 /ig/L. 

Thomaidis, N.S., Piperaki, E.A., (19%), Comparison of chemical modifiers for the determination of vanadium in water and oil samples by electrothermal atomization atomic absorption spectrometry. Analyst. 121,111-117. 

Yang, K. L., Jiang, S. J., and Hwang, T.J. (1996). Determination of titanium and vanadium in water samples by inductively coupled plasma mass spectrometry with on-line preconcentration./. Spectrom. 11(2), 139. 

Liu, H. and Jiang, S.-J. (2002) Determination of vanadium in water samples by reaction cell inductively coupled plasma quadrupole mass spectrometry. J. Anal. At. Spectrom., 17,556-9. 

Vanadium IlI) bromide, VBr3. Dark green or black (V plus Br2) gives green solution in water and green crystalline VBr3,6H20. Forms many complexes. 

Sulfur Polymer Cement. SPC has been proven effective in reducing leach rates of reactive heavy metals to the extent that some wastes can be managed solely as low level waste (LLW). When SPC is combined with mercury and lead oxides (both toxic metals), it interacts chemically to form mercury sulfide, HgS, and lead sulfide, PbS, both of which are insoluble in water. A dried sulfur residue from petroleum refining that contained 600-ppm vanadium (a carcinogen) was chemically modified using dicyclopentadiene and oligomer of cyclopentadiene and used to make SC (58). This material was examined by the California Department of Health Services (Cal EPA) and the leachable level of vanadium had been reduced to 8.3 ppm, well below the soluble threshold limit concentration of 24 ppm (59). 

Vanadium(IV) Oxysulfate. Vanadium(IV) oxysulfate pentahydrate (vanadyl sulfate), VOSO4 -5H20) is an ethereal blue sohd and is readily soluble in water. It forms from the reduction of V20 by SO2 in sulfuric acid solution. Vanadium(III) sulfate [13701 -70-7] ) is a powerful... 

Rheopectic behavior is the opposite of thixotropy. Shear stress increases with time at constant shear rate. Rheopeclic behavior has been obsei ved in bentonite sols, vanadium pentoxide sols, and gypsum suspensions in water (Bauer and Colhns, ibid.) as well as in some... 

In a 2-1. round-bottomed, 3-necked flask fitted with a stirrer and two large-bore condensers are placed 200 cc. of 50 per cent nitric acid and 0.25 g. of vanadium pentoxide. The flask is heated to 65-70° in a water bath (thermometer in water), and I cc. of cyclopentanone added. Oxidation is indicated by the production of brown fumes. The water bath is removed, and 42 g. (less the i cc.) of the cyclic ketone added from a dropping funnel through the condenser at the rate of a drop every three seconds. The heat of the reaction keeps the flask at about 70°. If the temperature drops, oxidation ceases until the ketone has accumulated, when it may proceed almost explosively. In such a case, or if the temperature is higher, much succinic acid is formed. After addition has been completed, the water bath... 

Hot corrosion is a rapid form of attack that is generally associated with alkali metal contaminants, such as sodium and potassium, reacting with sulfur in the fuel to form molten sulfates. The presence of only a few parts per million (ppm) of such contaminants in the fuel, or equivalent in the air, is sufficient to cause this corrosion. Sodium can be introduced in a number of ways, such as salt water in liquid fuel, through the turbine air inlet at sites near salt water or other contaminated areas, or as contaminants in water/steam injections. Besides the alkali metals such as sodium and potassium, other chemical elements can influence or cause corrosion on bucketing. Notable in this connection are vanadium, primarily found in crude and residual oils. 

Certain vertebrates have an astonishing ability to accumulate vanadium in their blood. For example, the ascidian seaworm Phallusia mammilata has a blood concentration of V up to 1900 ppm, which represents more than a millionfold concentration with respect to the sea-water in which it lives. The related organism Ascidia nigra has an even more spectacular accumulation with concentrations up to 1.45% V (i.e. 14 500 ppm) in its blood cells, which also contain considerable concentrations of sulfuric acid (pH 0). One possibility that has been mooted is that the ascidia accumulates vanadate and polyvanadate ions in mistake for phosphate and polyphosphates (p. 528). 

Vanadium in the feed poisons the FCC catalyst when it is deposited on the catalyst as coke by vanadyl porphydrine in the feed. During regeneration, this coke is burned off and vanadium is oxidized to a oxidation state. The vanadium oxide (V O ) reacts with water vapor in the regenerator to vanadic acid, HjVO. Vanadic acid is mobile and it destroys zeolite crystal through acid-catalyzed hydrolysis. Vanadic acid formation is related to the steam and oxygen concentration in the regenerator. 

Water The corrosion resistance of pure niobium in water and steam at elevated temperatures is not sufficient to allow its use as a canning material in water-cooled nuclear reactors. Alloys of niobium with molybdenum, titanium, vanadium and zirconium however have improved resistance and have possibilities in this application. Whilst the Nb-lOTi-lOMo alloy offers... 

FIGURE 16.7 Many vanadium Loni ioundt torm vividly colored solutions in water. The are also used in pottery glazes. Tine blue colors here aie due to the vanadvl ion V t) ... 

Vanadium(II) chloride dissolved in water is slowly oxidised by the solvent with evolution of hydrogen. Contact with platinum foil accelerates the reaction to violence. 

Cathodic stripping voltammetry has been used [807] to determine lead, cadmium, copper, zinc, uranium, vanadium, molybdenum, nickel, and cobalt in water, with great sensitivity and specificity, allowing study of metal specia-tion directly in the unaltered sample. The technique used preconcentration of the metal at a higher oxidation state by adsorption of certain surface-active complexes, after which its concentration was determined by reduction. The reaction mechanisms, effect of variation of the adsorption potential, maximal adsorption capacity of the hanging mercury drop electrode, and possible interferences are discussed. 

Prange, A. and K. Kremling. 1985. Distribution of dissolved molybdenum, uranium and vanadium in Baltic Sea waters. Mar. Chem. 16 259-274. 

L — maltolate the coordination environment of the vanadium in K[V02(malt)2] H2O is approximately octahedral, the two 0x0 ligands being in cis positions. [K(H20)e] units link adjacent vanadium(V) complex anions to give a chain structure 166). The main products of aerobic oxidation of [V O(dmpp)2l in aqueous solution are [V02(dmpp)] and [VOo(dmpp)2]. High pH favors these V products, whereas at low pH V species predominate 171). Vanadium(V) also forms a VO(OR)(malt)2 series, readily prepared from ammonium vanadate, maltol, and the appropriate alcohol in a water-alcohol-dichloromethane medium 172), and 3-hydroxy-4-pyridinonate analogues V0(0R)L2 on oxidation of their oxovanadium(IV) precursors in solution in the appropriate alcohol ROH 168). 

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