Electrolysis methods

The fused-salt electrolysis method is not suitable for obtaining pure materials of definite stoichiometry. 

Eatas E, Herrasti P, Aijona F, Garcia Camarero E (1987) Characterization of CdS thin films electrodeposited by an alternating current electrolysis method. J Electrochem Soc 134 2799-2801... 

Subba Rao GV, Tsang JC (1974) Electrolysis method of intercalation of layered transition metal dichalcogenides. Mater Res BuU 9 921-926... 

Allyl radicals can, of course, also be generated by electrolysis of the corresponding /J,y-unsaturated carboxylic acids together with a second carboxylic acid. This mixed Kolbe electrolysis method has been used to study the recombination of allyl radical 32 with the undecyl radical 3370. Recombination leads to the formation of adducts 34 and 35 in a ratio of 72 28, again preferring the product with the higher substituted double bond (equation 16). 

In addition to the electrolysis method for fractionating water, the distillation method could also be utiUzed by the imidirectional evaporation of a saturated brine at a sufl dently low temperature. While the theo-rectical efl ciency of the process is less than that for the evaporation of liquid hydrogen itself, the experimental technique is much simpler and the process could be operated continuously with very little attention. 

Currently, thermal reduction processes have replaced the electrolysis method. The starting material in these methods is limestone, which is calcined to produce calcium oxide. The latter is ground, mixed and compacted with aluminum, and reduced at temperatures between 1,000° to 1,200°C under vacuum. Calcium vapors formed in low yield under such thermodynamic conditions are transferred from the reactor and condensed in cool zones, thus shifting the equilibrium to allow formation of more calcium vapors. The reactions are as follows ... 

Oxygen may be produced by electrolysis of water. In such electrolytic procedure, small amounts of H2SO4 or NaOH may be added to water. Electrolysis methods, however, are not used as much commercially as are air bquefaction processes which cost less. However, in making hydrogen from water by electrolysis, oxygen is obtained as a by-product. 

Watts work laid the foundation for the current electrolysis method used to produce sodium hydroxide. This method was developed independently during the 1880s by the American chemist Hamilton Young Castner (1858- 1899) and the Austrian chemist Karl Kellner (1850-1905). Castner left Columbia University before graduating and developed a method to produce sodium more economically for use in the aluminum industry. Until the late 1800s, aluminum was considered a precious metal because it was difficult to obtain it in... 

Bard, A.J., and L.R. Faulkner. 1980. Bulk electrolysis methods, in Electrochemical Methods Fundamentals and Applications, AJ. Bard and L.R. Faulkner (eds.), John Wiley Sons, Inc., New York, pp. 370-428. 

Notably, advances in the direct, safe and continuous synthesis of neutral H202 solutions with concentrations of up to 8 wt% from 02 and water have been reported recently [64] using an improved electrolysis method involving a solid-polymer electrolyte (SPE). The formation and accumulation of neutral H202 were strongly... 

Thin layer — A layer of -+ electrolyte solution (molten salt electrolyte, - ionic liquid) of about 2 to 100 pm thickness is commonly treated as a thin layer because of particular properties and behavior. In bulk - electrolysis methods the amount of convertible species contained in a thin layer is very limited, thus exhaustive electrolysis becomes feasible. In numerous spectroelec-trochemical setups the electrolyte solution confined between the electrode surface under investigation and the... 

The industrial manufacturing methods of NF3 are classified in three categories electrolysis method, reactions of F2 with liquid phase ammonium-acid fluoride, and reactions of F2 with metal fluoride ammonium complex. 

Since we have not previously considered, what happens when current is present in an electrochemical cell, we begin with a discussion of this. Then bulk electrolysis methods are discussed in some detail. The voltammetric methods described in Chapter 23 also require a net current in the cell but use such small electrode areas that no appreciable changes in bulk concentrations occur. 

Fine colloidal or soluble inorganic contaminants are removed from water by physical-chemical methods of waste water cleaning. The main methods used are coagulation, oxidation, sorption, extraction and electrolysis methods. 

Masuda, M. Yoshida and A. Kashiwada, Electrolysis method of alkali halide solution,... 

T. Sata, A. Nakahara, T. Oda and S. Matsuura and N. Kuramoto, Electrolysis method of alkaline metal salt solution, Jpn. Pat. JP 56-54067 (examined application). 

The general considerations and models employed in electroanalytical bulk electrolysis methods are also often applicable to large-scale and flow electrosynthesis, to galvanic cells, batteries, and fuel cells, and to electroplating. 

Bulk electrolysis methods are also classified according to purpose. For example, one form of analysis involves determination of the weight of a deposit on the electrode (electrogravimetry). In this case 100% current efficiency is not required, but the substance of interest must be deposited in a pure, known form. In coulometry, the total quantity of electricity required to carry out an exhaustive electrolysis is determined. The quantity of material or number of electrons involved in the electrode reaction can then be determined by Faraday s laws, if the reaction occurred with 100% current efficiency. For electroseparations, electrolysis is used to remove, selectively, constituents from the solution. 

Several related bulk electrolysis techniques should be mentioned. In thin-layer electrochemical methods (Section 11.7) large AIV ratios are attained by trapping only a very small volume of solution in a thin (20-100 fxm) layer against the working electrode. The current level and time scale in these techniques are similar to those in voltammetric methods. Flow electrolysis (Section 11.6), in which a solution is exhaustively electrolyzed as it flows through a cell, can also be classified as a bulk electrolysis method. Finally there is stripping analysis (Section 11.8), where bulk electrolysis is used to preconcentrate a material in a small volume or on the surface of an electrode, before a voltammetric analysis. We also deal in this chapter with detector cells for liquid chromatography and other flow techniques. While these cells do not usually operate in a bulk electrolysis mode, they are often thin-layer flow cells that are related to the other cells described. 

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