Fused salt electrolytes

Anode Applications. Graphite has been used as the primary material for electrolysis of brine (aqueous) and fused-salt electrolytes, both as anode and cathode. Technological advances, however, have resulted in a dimensionally stable anode (DSA) consisting of precious metal oxides deposited on a titanium substrate that has replaced graphite as the primary anode (38—41) (see Alkali and chlorine products). 

Electrochemical deposition of metals and alloys involves the reduction of metal ions from aqueous, organic, and fused-salt electrolytes. In this book we treat deposition from aqueous solutions only. The reduction of metal ions in aqueous solution is... 

In this case a fused salt electrolyte, incorporating ZnCl2 dissolved in a eutectic mixture of LiCl and KCl, is used to determine the activity gradient between pure liquid Zn and a ternary Zn-In-Pb alloy, also in the liquid state. The EMF arises from the potential between pure Zn at imit activity to Zn in the alloy where the activity has a value, ci. The ruling equation then becomes... 

W.D. Threadill, The Calcium Chloride-Calcium Oxide Fused Salt Electrolytic System Solubilities, Metal Contents and Freezing Points, J. Electrochem. Soc. 112 (1965) 632-633. 

Electrolysis through fused salts. Electrodeposition of metal fuel through a fused-salt electrolyte to separate uranium and plutonium from fission products was studied at Knolls Atomic Power Laboratory [N6]. 

In a certain aspect the Kroll and Hunter metallothermic reduction processes can be seen as indirect electrowinning processes that rely on fused salt electrolytic production of magnesium or sodium for reduction of TiCl, Battelle Columbus Laboratories (1975) - Interim Report on Energy Use Patterns in Metallurgical Processing. -Columbus, OH. 

Sarla, R.M. Schneidersmaim, E.O. (1960) Fused salt electrolytic cell for producing high-melting reactive metals, such as tantalum. US Patent 2,957,816. 

The two types of high temperature fuel cell are quite different from each other (Table 6). The molten carbonate fuel cell, which operates at 650°C, has a metal anode (nickel), a conducting oxide cathode (e.g. lithiated NiO) and a mixed Li2C03/K2C03 fused salt electrolyte. Sulphur attack of the anode, to form liquid nickel sulphide, is a severe problem and it is necessary to remove H2S from the fuel gas to <1 ppm or better. However, CO is not a poison. Other materials science problems include anode sintering and degradation, corrosion of cell components and evaporation of the electrolyte. Work continues on this fuel cell in U.S.A. and there is some optimism that the problem will be solved within 10 years. 

There is clearly benefit in using brine solutions with a high chloride concentration where solubility differentials of the order of 50 g/L of lead can be obtained. Many process developments have therefore proposed to use crystallisation simply by cooling the leach solution as a means of obtaining pure lead chloride. The crystals must then be thoroughly washed and dried in preparation for feeding to a fused salt electrolytic cell. 

H. Shimotake and E. J. Cairns, A Lithium/Tin Cell with an Immobilized Fused-Salt Electrolyte Cell Performance and Thermal Regeneration Analysis, 3rd Annual Intersociety Energy Conversion Engineering Conference (lECEC) Record, Boulder, CO, Aug. 13-17, 1968, p. 76. 

Fused-salt electroplating, which is commonly referred to as metal-liding, is a process for surface modification and surface hardening by electrodeposition fiom fused-salt electrolytes. Two unique aspects of this electrodeposition process are (1) elements that cannot be plated by conventional processes may plate by fused-salt electrodeposition and (2) if the deposition rate is controlled to match the diffusion rate of the... 

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