Zinc deposit, carbons

Both share more or less the same merits but also the same disadvantages. The beneficial properties are high OCV (2.12 and 1.85 V respectively) flexibility in design (because the active chemicals are mainly stored in tanks outside the (usually bipolar) cell stack) no problems with zinc deposition in the charging cycle because it works under nearly ideal conditions (perfect mass transport by electrolyte convection, carbon substrates [52]) self-discharge by chemical attack of the acid on the deposited zinc may be ignored because the stack runs dry in the standby mode and use of relatively cheap construction materials (polymers) and reactants. 

Anderson, G. M. and G. Garven, 1987, Sulfate-sulfide-carbonate associations in Mississippi Valley-type lead-zinc deposits. Economic Geology 82,482 488. 

Distal exhalative manganese enriched stratigraphy to carbonate-hosted zinc deposits, Adirondack Lowlands, New York State, U.S.A. 

Cadmium was discovered by F. Stromeyer in 1817. In nature, it is mostly found in zinc deposits. The mineral, greenocktite (CdS) is found associated with the zinc ore, sphalerite (ZnS). Similarly zinc carbonate contains otavite (CdCOs) in small amounts. Its abundance in the earth s crust is estimated to he 0.15 mg/kg and in sea water 0.11 irg/L. 

Raeissi et al. [236, 237] showed that temperature, pH, and current density affected the morphology and texture, as well as the nucleation mechanism of the zinc deposits on carbon steel electrode. 

Hanor J. S. (1996b) Controls on the solubilization of lead and zinc in basinal brines. In Carbonate-hosted Lead-Zinc Deposits, Economic Geology Special Publication 4 (ed. D. F. Sangster). Soc. Econ. Geologists IMC, Littleton, CO, pp. 483-500. 

Kyle J. R. and Saunders J. A. (1997) MetalUc deposits of the Gulf Coast Basin diverse minerahzation styles in a young sedimentary basin. In Carbonate-hosted Lead—Zinc Deposits (ed. D. F. Sangster). Society of Economic Geologists, Littleton, CO, vol. 4, pp. 218—229. 

Anderson, G. M., 1983, Some geochemical aspects of sulfide precipitation in carbonate rocks in International conference on Mississippi Valley Type lead-zinc deposits, Rolla,... 

Brannon, J. C., Podosek, F. A., and Cole, S. C., 1997, Radiometric dating of Mississippi Valley-type ore deposits in Sangster, D. F., ed.. Carbonate-hosted lead-zinc deposits Special Publication - Society of Economic Geologists, p. 536-545. 

Erickson, R. L., Mosier, E. L., Viets, J. G., Odland, S. K., and Erickson, M. S., 1983, Subsurface geochemical exploration in carbonate terraines Midcontinent, U.S.A. in Kisvarsanyi, G., Grant, S. K., Pratt, W. P., and Koenig, J. W., eds.. International conference on Mississippi Valley-type lead-zinc deposits proceedings volume Rolla, Missouri, University ofMissouri Press, p. 575-583. 

Carbonate-hosted lead-zinc deposits. Special Publication, Sangster, D.F., ed.. Society of Economic Geologists, p. 483-500. 

Bush, P., 1979. Carbonate coastal sabkhas — the precursor of Mississippi Valley type lead zinc deposits. Am. Inst. Min. Eng., Annu. Meet, Feb. 18—22, 1979. 

Analyses of fluid inclusions in saddle dolomite were first reported for the Pine Point lead-zinc deposit in western Canada (Roedder, 1968), but it was not until the late 1980s that fluid-inclusion analysis was widely applied to the study of carbonate cements. 

All over the world there are many oxidized, silicated and carbonated zinc deposits that have never been exploited mainly because conventional technologies, developed for zinc sulfides, showed significant technical difficulties when applied to these ores. 

Leung PK, Ponce-de-Leon C, Low CTJ, Walsh FC (2011) Zinc deposition and dissolution in methanesulfonic acid onto a carbon composite electrode as the negative electrode reactions in a hybrid redox flow battery. Electrochim Acta 56 6536-6546. doi 10.1016/j.electacta.2011.04. Ill... 

Fig. 4.1 Cyclic voltammogram showing zinc deposition and de-plating for carbon black (green line) and multiwall carbon nanotube-embedded (orange line) high-density polyethylene composite electrodes, with deposition potential (DP), cross-over potential (COP) and nucleation overpotential (NOP) indicated on diagram inset (Image adapted from [3].)...

Zinc deposited onto a clean carbon plastic surface is smoother than when deposited on top of zinc but zinc can be completely removed by total discharge to renew the surface. This is, in effect, a 100% depth of discharge and does not damage the battery but improves it. In practieal applications the battery should complete many cycles before a strip cycle is run. A plot of the cycling efficiencies of a 15-kWh battery is shown in Fig. 39.4. The periodic nature of cycles 60 to 200 is a result of multiple tests in which five cycles were followed by a strip cycle and also occasionally a baseline cycle. The first new cycle is only slightly lower in efficiency because fhe base coat of zinc is being replated. 

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