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Electrohydrodynamic flows are studied at a cyclohexane-castor oil interface. It is established that there is a series of electrohydrodynamic effects, depending on electrode polarity, electric field voltage and location of an electrode with respect to the phase interface, whose consideration in constructing devices that operate with the use of electric fields will make it possible to optimize the processes that occur and increase the efficiency of their operation.Electrohydrodynamic flows have been known as a physical effect for a long time. However, due to difficulty of experimental studies and the variety of theoretical models, reliable qualitative and quantitative data for developing electrohydrodynamic devices (electrodehydrators, electrodispersers, etc.) have not yet been obtained.In order to study the mechanism of electrohydrodynamic effects (EHD effects) with the aim of obtaining a model for processes that occur and subsequent development of electrohydrodynamic devices, the interface of liquid-liquid phases has been studied [1][2][3][4][5][6][7]. Recent work has modeled the interface of oil-water phases. In view of the complexity of visual observation of the interface of real oil-water media (oil is not transparent and it is inhomogeneous) such liquids as cyclohexane and castor oil were chosen, that are difficult to mix, maintain a clear interface over time, sufficient in order to observe and record EHD effects within them. The physicomechanical properties of castor oil (density, viscosity, electrical conductivity, etc.) are close to similar properties of oil. Cyclohexane, selected as an analog of water, in the case of flat interface of phases makes it possible, in contrast to water, that boils with an increase in voltage and consequently current strength, to create a high-voltage electrical field.A device was used for the study intended for examining the effect of electrical fields on the nature of flow in different liquids and at the interface of two flowing media, which consisted of an electrical and optical systems. In the electrical system there was a transformer, controlling an alternating voltage from 0 to 220 V; a voltage transformer with a n output voltage from 0 to 20 kV; a kilovoltmeter and a microammeter making it possible to measure voltage from 0 to 25 kV, and current strength from 0 to 500 μA. Flat aluminum electrodes with a size of 70 × 30 × 1 mm and copper rod electrodes 2 mm in diameter were used for the study. Within the optical system there was a cell for observing the processes that occur (rectangular cell with a size of 70 × 65 × 30 mm made of mirror glass 5 mm thick with a cine and photocamera, and a source of illumination making it possible to record the observed effects).Studies were performed as follows. First castor oil, and then cyclohexane in the ratio 2:5 (20 and 50 ml) were poured into a cell. The cell was installed on an insulated base. Electrodes were fastened by means of special attachment to different distances from the cyclohexane-castor oil phase interface, varying the ...

The possibility of using various materials as electrodes for membraneless fuel cells based on immiscible liquids, both from the standpoint of the thermodynamic possibility of the process and from the point of view of their corrosion resistance, is considered. The corrosion resistance of materials from alloys based on iron, as well as carbon was investigated for use as electrodes in membraneless fuel cells based on immiscible liquids. The possibility of using them instead of electrodes based on ruthenium and platinum in the studied alkaline aqueous ethanol system was shown. It was found that the highest electromotive force in the system occurs when using an activated carbon anode in the top ethanol phase and a carbon steel 10 cathodes in the bottom aqueous phase. The possibility of using activated carbon instead of a ruthenium-coated titanium electrode and platinum-coated titanium electrode, at almost equal exchange currents, will significantly reduce the cost of manufacturing a fuel cell. Thus under certain conditions, this type of fuel cell can compete with membrane fuel cells that have received industrial implementation

BACKGROUND: This study investigates the catalytic activity of platinized titanium and titanium coated with ruthenium oxide in the processes of electrooxidation of ethyl alcohol in alkaline phosphate electrolyte and potassium hydroxide electrolyte in nonflowing membraneless fuel cells proposed by the authors. In these systems, an interface between the phases formed, which played the role of a membrane. Cyclic voltammetry, pulse chronoamperometry and gas-liquid chromatography were used to study the corrosion resistance and catalytic activity of ethanol oxidation on the selected electrodes. Platinized titanium and titanium coated with ruthenium oxide, involving a thin layer of platinum or ruthenium oxide on a perforated titanium mesh, were investigated. RESULTS: It is found that the oxidation of ethyl alcohol proceeds more actively on the surface of titanium coated with ruthenium oxide in alkaline phosphate electrolyte, with the formation of acetaldehyde as the main reaction product. In potassium hydroxide electrolyte, acetaldehyde and acetic acid are formed on the surface; two and four electrons are released, respectively. This indicates the C2 reaction pathway of ethanol oxidation. In contrast, the oxidation of ethyl alcohol in potassium hydroxide electrolyte proceeds more actively on the platinized titanium with the formation of acetaldehyde. CONCLUSIONS:The results obtained show that titanium electrode coated with ruthenium oxide is promising in phosphate electrolyte, but platinized titanium electrode is promising in potassium hydroxide electrolyte in the proposed non-flowing membraneless alcohol fuel cells.

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