Electrolyte, solid, sulfur dioxide

Shiokawa, 1985b, J. Electrochan. Soc. 132,2519. Imanaka, N., G. Adachi and J. Shiokawa, 1986a, A solid electrolyte for sulfur dioxide detection, sodium sulfate mixed with rare earth sulfates and silicon dioxide, ACS Symposium on Chemical Sensors -Fundamentals and Applications (American Chemical Society) p. 121. 

The use of equation (3.2) to study the behaviour of catalysts is known as solid electrolyte potentiometry (SEP). Wagner38 was the first to put forward the idea of using SEP to study catalysts under working conditions. Vayenas and Saltsburg were the first to apply the technique to the fundamental study of a catalytic reaction for the case of the oxidation of sulfur dioxide.39 Since then the technique has been widely used, with particular success in the study of periodic and oscillatory phenomena for such reactions as the oxidation of carbon monoxide on platinum, hydrogen on nickel, ethylene on platinum and propylene oxide on silver. 

Other low-temperature studies have been motivated by the desire to characterize and understand processes occurring in unusual media. For example, the use of liquid ammonia [8-10] and liquid sulfur dioxide [11-13] naturally requires reduced temperatures unless high pressures are used, as is done for electrochemistry in supercritical fluids [14]. Frozen media are interesting systems in terms of mass transport phenomena and microstructural effects. Examples include glasses of acetonitrile and acetone [15], frozen dimethyl sulfoxide solutions [16,17], and the solid electrolyte HC104 5.5 H20 [18-20]. 

A new solid state chemical sensor for sulfur dioxide utilizing a sodium sulfate/rare earth sulfates/silicon dioxide electrolyte has been developed. The addition of rare earth sulfates and silicon dioxide to the sodium sulfate electrolyte was found to enhance the durability and electrical conductivity of the electrolyte. The electrolyte exhibits a Nernstian response in the range of SC gas concentrations from 30 ppm to 1 %. 

Chloro(l,5-cyclooctadiene) (triphenylarsine)platinum(II) tetrafluoroborate is a white, air-stable solid. It is sparingly soluble in polar organic solvents and insoluble in nonpolar ones. A 10-3 M solution in acetone shows a conductivity characteristic of a 1 1 electrolyte.1 Its proton magnetic resonance spectrum (in liquid sulfur dioxide solution, at 60 MHz., with internal tetramethylsilane reference) shows bands due to the coordinated olefin at 3.59 [two protons 55 Hz.], 5.01 [two... 

Worrell, W.L. and Liu, Q.G. (1984) A new sulfur dioxide sensor using a novel two-phase solid-sulfate electrolyte. 

Inaba. Y, Tamura, S. and Imanaka, N. (2007) New type of sulfur dioxide gas sensor based on trivalent Al ion-conducting solid electrolyte. Solid State Ionics, 179, 1625-7. 

Thermodynamic equilibria are also of principal importance, if one wishes to determine carbon dioxide or sulfur dioxide with carbonates or sulfates which show conductance for sodium or potassium ions. It is not the ion migrating through the solid, but the electrochemical equilibrium between molecules in the gas phase, particles in the solid electrolyte and electrons in the electrical conductor that determine the electrode potential utilizable in sensors. 

Imanaka N., Yamaguchi Y, Adachi G., and Shiokawa J., Sulfur dioxide gas detection with Na2S04-Li2S04-Y2(S04)3-Si02 solid electrolyte by a solid reference electrode method, J. Electrochem. Soc., 134, 725-728, 1987. 

Thionyl chloride is also irreversibly reduced with the formation of a solid lithium chloride deposit and a certain amount of elementary sulfur along with the formation of sulfur dioxide dissolved in electrolyte ... 

The density of sulfur is close to that of lithium chloride. The volume of solid sulfur formed in reaction (11.9) is less than 16% of the overall volume of solid products. Sulfur dioxide formed in reaction (11.9) is rather soluble in electrolyte, so that the intrinsic pressure in the cells is enhanced negligibly. Despite this, the cases of thionyl chloride-lithium cells are made to be rather strong and the extreme corrosion activity of thionyl chloride enforces application of high-alloy steels or nickel. Sintered glass-metal pressure seals are used in thionyl chloride-lithium cells, same as in cells with some other systems. 

Nitrogen dioxide can also be selectively detected by an electrode with a chalcogenide (Se6oOe28Sbi2) membrane, without interference from nitric oxide, sulfur dioxide, carbon monoxide, methane, and other gases. Another solid-state sensor for NO2 employs an alkaline nitrate electrolyte at a temperature of 800°C. 

Potential safety concerns with lithium-metal anodes and a flammable electrolyte. However, they have an excellent safety record in the field, and the safety of the solid cathode cells is generally regarded as being much better than that of lithium cells using liquid cathodes (thionyl chloride or sulfur dioxide) used primarily in industrial/military applications. These and other characteristics have made... 

Lithium cells with liquid cathodes, such as sulfur dioxide, offer higher energy density, improved rate capability, and enhanced low-temperature performance compared with those with solid electrolytes. 

Lithium batteries use nonaqueous solvents for the electrolyte because of the reactivity of lithium in aqueous solutions. Organic solvents such as acetonitrile, propylene carbonate, and dimethoxyethane and inorganic solvents such as thionyl chloride are typically employed. A compatible solute is added to provide the necessary electrolyte conductivity. (Solid-state and molten-salt electrolytes are also used in some other primary and reserve lithium cells see Chaps. 15, 20, and 21.) Many different materials were considered for the active cathode material sulfur dioxide, manganese dioxide, iron disulfide, and carbon monofluoride are now in common use. The term lithium battery, therefore, applies to many different types of chemistries, each using lithium as the anode but differing in cathode material, electrolyte, and chemistry as well as in design and other physical and mechanical features. 

In these solid electrolytes, the species migrating in the solid phase are sodium ions and not suliiir oxides. Therefore, by using this chemistry, we can devise an appropriate sensor arrangement. The gas to detect is SO2 and the ionic state of SO2 gas is SO . As Na+ is the mobile cation in the solid electrolyte, sodium sulfate, which is the combination of both Na and SO ", should be formed on the solid electrolyte surface. In the sulfur dioxide gas sensor with those solid electrolytes, sodium sulfate is used to detect SO2 gas. 

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