Metal recovery in a pilot-scale rotating cylindrical wiper-blade electrode system

The performance of an experimental pilot-scale electrochemical reactor using a rotating cylindrical electrode equipped with wiper blades is described. Data obtained from monopolar depositing and bipolar stripping—depositing of copper from dilute aqueous electrolytes are presented and certain economic aspects of metal recovery are discussed.     

The anodic oxidation of methanol via continous electrode reactivation

The anodic oxidation of methanol in a rotating tripolar wiper blade cell has been studied to determine experimental condition required for continuous reactivation of the electrode surface. A plausible mechanism of the reactivated oxidation reaction is also presented.     

Hydrodynamic models in magnetoelectrolysis

In dc electrolysis superposition of a uniform magnetic field enhances mass transfer rates at the electrodes. The effect is analysed in terms of a vorticity generation model and various equivalent mass transfer models. The latter predict decreasing boundary layer thicknesses with increasing magnetic field strengths and permit a relatively simple interpretation of the augmented mass transfer via hydrodynamic principles.     

High oxide ion conduction in sintered oxides of the system Bi2O3-Y2O3

The ionic conduction in sintered Bi₂O₂-Y₂O₃ was investigated by measuring the conductivity and the emf of an oxygen concentration cell using the specimen tablet as electrolyte. The face centred cubic phase in this system was found to show high oxide ion conduction accompanied by a little electronic conduction when exposed to air. This phase was stable with a composition of 25 ～ 43 mol % Y₂O₃ over a wide range of temperatures, and the oxide ion conductivity increased with decrease in Y₂O₃. The conductivities of (Bi₂O₃)_0.75 (Y₂O₃)_0.25 were 1.6×10^?1 Ω^?1 cm^?1 at 700°C and 1.2×10^?2 Ω^?1 cm^?1 at 500°C values which are many times higher than those of stabilized zirconia (ZrO₂)_0.90(Y₂O₃)_0.10 at corresponding temperatures. Specimens containing less than 25 mol % Y₂O₃ showed a phase transition at 700 ～ 580°C and the conductivities decreased remarkably below these temperatures. High oxide ion conduction in the fcc phase is attributed to the migration of oxide ion vacancies which were present in an appreciable amount.     

Magnetoelectrolysis with rough cathode surfaces

In coupled electric/magnetic fields the upward drift of the apparent current density at a rough cathode is increased in proportion to the strength of the imposed magnetic field. The extent of enhancement becomes relatively less as the magnetohydrodynamic body force in the electrolyte becomes larger.     

The effect of a magnetic field on electrolyte conductivity

A simple theory of electrolyte conductance is coupled electric/magnetic fields is presented. The procedure for estimating the relative importance of Hall conductivity is quicker than others hitherto proposed.     

Mechanisms of degradation of cotton and effects of mercerization-stretching upon the course of these mechanisms,part VII. Characterization of microstructural differences between scoured cotton and slack mercerized-stretched cottons

Conditions were established to introduce almost equal and reproduciple amounts of diethylaminoethyl (DEAE) substituents into the molecular structure of scoured cotton (substrate I), slack mercerized cotton (substrate II), slack mercerized-stretched (94%, substrate III), and slack mercerized-stretched (103%, substrate IV) cotton. Similarities between the original structures of these substrates before and after the chemical modification were assessed by X-ray analysis. Comparison between the DEAE cottons and the corresponding unmodified cottons upon acid hydrolysis with respect to moisture regain, loss in weight and degree of polymerization was also made. Chemical analysis was used to study the compositions and structures of the hydrolyzates (i.e., hydrocelluloses and solublized fractions) resulting from hydrolysis of the modified cottons with 2.5 N HCl under reflux for different lengths of time. Studies of rates of hydrolysis of the cellulose, rates of removal of substituted glucoses and rates of removal of individual types of substituted glucose units were considered as means to provide information regarding: (a) distribution of DEAE substitutents throughout the structure of cellulose, (b) nature of accessible regions where the DEAE substituents are developed, and (c) selective availability of the hydroxyl groups at C-2, C-3 and C-6 of the D-glucopyranosyl units in the cellulose elementary fibril.     

High ionic conduction in tetragonal solid solution of the system La2O3-MgF2

LaOF-type tetragonal solid solution was found in the system La₂O₃–MgF₂. This phase showed higher anionic conduction than the previously reported cubic solid solution in the system La₂O₃–CaF₂. Electrolysis by Tubandt's method showed that fluoride ion conduction was dominant in this solid solution. The fluoride ions were considered to be easily substituted by oxide ions through cathode reaction in the oxygen atmosphere.     

Upper critical solution temperature lubricants for CPVC

Chlorinated polyvinyl chloride (CPVC) is often used in injection molding for products that demand high heat resistance. However, proper control of its flow properties is difficult. To improve flow behavior some internal lubricants are usually used, but they reduce heat resistance of the products. Upper critical solution temperature (UCST) lubricants were found to enhance its flow properties, and also high heat resistance was retained. They act as internal lubricants during processing, improving flow and phase separation during cooling. Therefore they are present essentially as inert filler and thus have little effect on heat distortion temperature.