Zinc in water

Reactions with aqueous solutions. Uniform dissolution or corrosion of metals in acid, alkaline or neutral solutions (e.g. dissolution of zinc in hydrochloric acid or in caustic soda solution general corrosion of zinc in water or during atmospheric exposure). Reactions with non-aqueous solution (e.g. dissolution of copper in a solution of ammonium acetate and bromine in alcohol). 

The effect of temperature on the corrosion of zinc in water It is found that the temperature has a marked effect on the rate at which zinc corrodes in water. The corrosion rate in distilled water reaches a maximum in the temperature range 65-75°C. This variation in the corrosion rate with temperature is attributed to changes in the nature of the protective film. At lower temperatures the film is found to be very adherent and gelatinous, while at temperatures around 70°C it becomes distinctly granular in character and much less adherent. Above 75°C it again tends to become more adherent and assumes a very compact and dense form. It is believed that the granular coating formed at temperatures around 70°C is more porous... 

Wiederholt, W. Behaviour of Zinc in Water, Metall-Verlag GmbH, Berlin, 162, English typescript translation available in ZDA library (1965)... 

Chan and Li reported that conjugated 1,3-butadienes were produced in moderate yields when carbonyl compounds reacted with 1,3-dichloropropene and zinc in water (Eq. 8.29).61 The use of 3-iodo-1-chloropropene instead of 1,3-dichloropropene greatly improved the yields. When the reactions were interrupted after their initial allyla-tions, subsequent base treatment of the intermediate compounds produced vinyloxiranes in high yields. Similarly, reactions of carbonyl compounds with 3-iodo-2-chloromethyl-l-propene followed by base treatment produced 2-methylenetetrahydrofurans (Eq. 8.30).62 Thus, the 3-iodo-2-chloromethyl-l-propene served as a novel trimethylene-methane equivalent.63... 

Clerici and Porta reported that phenyl, acetyl and methyl radicals add to the Ca atom of the iminium ion, PhN+Me=CHMe, formed in situ by the titanium-catalyzed condensation of /V-methylanilinc with acetaldehyde to give PhNMeCHMePh, PhNMeCHMeAc, and PhNMeCHMe2 in 80% overall yield.83 Recently, Miyabe and co-workers studied the addition of various alkyl radicals to imine derivatives. Alkyl radicals generated from alkyl iodide and triethylborane were added to imine derivatives such as oxime ethers, hydrazones, and nitrones in an aqueous medium.84 The reaction also proceeds on solid support.85 A-sulfonylimines are also effective under such reaction conditions.86 Indium is also effective as the mediator (Eq. 11.49).87 A tandem radical addition-cyclization reaction of oxime ether and hydrazone was also developed (Eq. 11.50).88 Li and co-workers reported the synthesis of a-amino acid derivatives and amines via the addition of simple alkyl halides to imines and enamides mediated by zinc in water (Eq. 11.51).89 The zinc-mediated radical reaction of the hydrazone bearing a chiral camphorsultam provided the corresponding alkylated products with good diastereoselectivities that can be converted into enantiomerically pure a-amino acids (Eq. 11.52).90... 

The zinc content of the overflow water from the densator-reactor is set by the pH-solubility relationship of zinc in water and results in a zinc content of 0.5 to 1 mg/L at pH = 10. Once the precipitated zinc is removed from the wastewater, the pH can be readjusted to a lower value. 

Miller, P.A., K.R. Munkittrick, and D.G. Dixon. 1992. Relationship between concentrations of copper and zinc in water, sediment, benthic invertebrates, and tissues of white sucker (Catostomus commersoni) at metal-contaminated sites. Canad. Jour. Fish. Aquat. Sci. 49 978-984. 

The paper [8] includes results of investigating electron mechanisms of the impact of active particles, radicals, hydrated electrons artificially generated by plasma on the behavior of cyanide complexes of zinc in water solutions. The above investigation was conducted using quantum chemistry methods. Quantum-chemical calculation of electron structure of the complexes Zn(CN)42 4EP-20H- with complete optimization of all geometric parameters [9] was performed. 

Zinc also can be identified in aqueous solutions by colorimetric methods. Two such methods, known as dithizone and zincon methods are applicable to analyze zinc in water (APHA, AWWA, and WEF. 1999. Standard Methods for the Examination of Water and Wastewater, 20 ed. Washington, DC American Public Health Association). 

AAS is used in a number of limit tests for metallic impurities, e.g. magnesium and strontium in calcium acetate palladium in carbenicillin sodium and lead in bismuth subgallate. It is also used to assay metals in a number of other preparations zinc in zinc insulin suspension and tetracosactrin zinc injection copper and iron in ascorbic acid zinc in acetylcysteine lead in bismuthsubcarbonate silver in cisplatinum lead in oxyprenolol aluminium in albumin solution and calcium, magnesium, mercury and zinc in water used for diluting haemodialysis solutions. 

Mann, A. W. Deutscher, R. L. 1980. Solution chemistry of lead and zinc in water containing carbonate, sulfate and chloride ions. Chemical Geology, 29, 293-311. 

In contrast, copper-activated zinc in water/dimethylformamide mixture attacks both the C4- F and chlorine bonds to give a mixture of monoreduced products.71... 

The various carbon-metal bond energies needed have been taken from the compilation of Skinner4, as have also the heats of vaporisation of the organometallic compounds. The heats of solution of liquid dimethylzinc and dimethylmercury have both been assumed to be +2 kcal.mole-1 (the heat of solution of dimethyl-zinc in water, to give dimethylzinc in aqueous solution, is, of course, a purely formal value). 

An example of a method suitable for the determination of cadmium, cobalt, copper, iron, manganese, nickel, and zinc in water, using chelation and sample extraction, is as follows [113]. The sample is filtered through an acid-washed membrane filter as soon as possible after collection. It is then acidified with nitric acid for preservation until analysis. This will give the soluble metal fraction. If the total metal content is to be found, the sample is acidified and allowed to stand for 4 days with occasional shaking. Then it is filtered. 

Both aryl and alkyl halides have been reduced by zinc in water with a nickel complex, generated in situ, in almost quantitative yields134. A similar reaction has also been performed using ultrasonic irradiation135. 

In contrast to inorganics such as mercury, copper, arsenic, lead, and cadmium, there have been fewer studies that focus only on zinc removal by carbonaceous adsorbents [199-203]. The presence of zinc in water appears to be due primarily to corrosion of galvanized metals [33]. The dominant oxidation state in aqueous solution is Zn(II), while the dominant species (see Fig. Al) are Zn at pH < 9 and Zn(OH), at pH > 9 [202]. 

U. Gorlach, C. F. Boutron, Preconcentration of lead, cadmium, copper and zinc in water at the pg g" level by non-boiling evaporation. Anal. Chim. Acta, 236 (1990), 391-398. 

Goede, A.A. (1985) Mercury, selenium, arsenic and zinc in waters from the Dutch Wadden Sea. Environmental Pollution yjA., 287-309. 

Zinc (and Cu) in brass and tap water were determined with the use of zincon after preliminary preconcentration on Chelex-100 column [3]. The application of V-hydroxy-AW-diphenylbenzamidine and diphenylcarbazone to the determination of zinc in airborne dust particulates has been described [4]. Trace amounts of zinc in standard alloys, environmental and pharmaceutical samples were determined by fourth derivative spectrophotometry using PAN as a reagent and ammonium tetraphenylborate supported on naphthalene as an adsorbent [5]. The detection limit was 9.5 ng ml Zn. Submicrogram amounts of zinc in water and rock samples were determined with 5-(2 -carbomethoxyphenyl)azo-8-quinolinol in the anionic micellar medium of sodium dodecyl sulfate [6]. 

Chan and Li reported that conjugated 1,3-butadienes were produced in moderate yields when carbonyl compounds reacted with 1,3-dichloropropene and zinc in water (Eq. 8.29). The use of 3-iodo-... 

The concentrations of zinc in water samples from Whitewood Creek, South Dakota, were measured by Hale (1977). The samples were collected upstream from the discharge of a local mining company. In 42 analyses, zinc concentrations ranged from <0.004 to 0.048 mg/L with a mean concentration of 0.018 mg/L. The level of dissolved zinc in water from Lakes Erie and Ontario ranged from 3x10 to 1.1 x10" mg/L (Coale and Flegal 1989). 

Sprenger, M. A. McIntosh, 1989. Relationship between concentrations of aluminum, cadmium, lead, and zinc in water, sediments and aquatic macrophytes. Arch. Envir. Contam. Toxicol. 18 225-231. 

Karpuhin, V. T. Malikov, M. M. Val yano, G. E. Borodina, T. I. Gololobova, O. A. Investigation of the characteristics of a colloidal solution and its solid phase obtained through ablation of zinc in water by high power radiation from a copper vapor laser . High Temp+, 2011,49(5), 681-686. 

BecquereP used a cell consisting of zinc in zinc sulphate or nitrate solution and copper in copper nitrate solution, the liquids separated by goldbeater s skin, and found it fairly constant, more so if the copper was surrounded by dilute sulphuric acid and the zinc by a mixture of sulphuric and nitric acids. Poggendorff said this cell had some resemblance to the constant battery of Danieir, but was less constant. F. Wach used zinc in water and copper in copper sulphate solution, the liquids separated by bladder. 

Zaporozhets, O. A. Tsyukalo, L. E. Test determination of lead and zinc in water with the use of xylenol orange immobilized on silica. J. Anal. Chem. 2004, 59, 386-391. 

Of all the anions, chloride is most corrosive to zinc in water, especially if it is present in amounts exceeding SO mg/L. The softer the water, and the lower it is in carbonate, the more pronounced is the effect of chloride. Thus, a chloride content of 80 mg/L in soft water causes quite severe corrosion, while in hard water no corrosion occurs even with 700 mg/L (GAV, 1961). 

Wormwell (1953) observed that at 1.5-2% concentration, borax affords complete protection to zinc in contact with certain waters. Sodium benzoate was found to afford partial protection to zinc in water as a result of experiments made to assess its beneficial effect on steel corrosion (Wormwell and Mercer, 1952 Grover et al., 1961). Sodium nitrate similarly reduces the corrosion of zinc in water, while sodium hydrogen phosphate and sodium silicate can afford complete protection. Wormwell and Mercer also showed that sodium cinnamate affords partial protection to zinc in water sodium o-nitrohydrocinnamate, sodium m-nitrociimamate, and sodium p-nitrocinna-mate protect it adequately. 

Fig. 3.7 Effect of temperature and excess pressure (over atmospheric) on corrosion of zinc in water (Weast et al., 1961).

Bianchini, A., Pozzoli, S., and Lanfranco, G. (1968). Anodic behavior of zinc in water and diluted aqueous solutions. Research Report, Centro Ricerche Metal-lurgiche SpA, Turin, December, 51 pp. 

In aqueous corrosion, raising the temperature increases the dissolution of zinc in water. A marked increase occurs up to around 60°C followed, by a decrease at higher temperatures due to the decrease in oxygen supply and the formation of more compact and adherent scale. Intergranular corrosion of zinc casting alloys is a risk above 70 C in wet or humid conditions, such as in steam, when no protective layer can form and selective dissolution of the structure occurs. In hot hard waters, scale forms at water temperatures above 55 C. This scale has a coarse grain structure and does not adhere well to the zinc surfece. Corrosion of the zinc occurs locally because of the discontinuities in the scale or local electrochemical action. Above 60°C, zinc usually becomes cathodic to steel therefore, the steel will corrode to protect the zinc coating. 

T. Hwang and S. Jiang. Determination of trace amounts of zinc in water samples by flow injection isotope dilution inductively coupled plasma mass spectrometry. Analyst 122 233-239, 1997. 

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