Cathode coating high-surface area

Mercury represents a serious environmental risk, and the study of removal of mercury from wastewater has received considerable attention in recent years. Mercury concentration was usually reduced by deposition on a cathode with high surface area. Removal of mercury is studied using extended surface electrolysis which reduces the level of mercury to below acceptable concentrations of 0.01 ppm in wastes by employing a Swiss roll cell with a cadmium-coated, stainless-steel cathode. An industrial cell with a fluidized bed electrode has also been studied. Graphite, as an efficient porous electrode, has been used to remove traces of mercuric ions form aqueous electrolyte solutions. In order to apply the electrochemical method for some effluents, it is necessary to use sodium hypochlorite to convert elemental mercury and less soluble mercury compounds to water-soluble mercuric-chloride complex ions. 

Certain proprietary zinc and aluminum filled polymers and some ion vapor deposited aluminum coatings, applied to steel fasteners may actually produce more damage than the untreated steel fastener itself. This was attributed to two possible causes either the high surface area involved with each of the particulate coatings or the contamination of the particulate surface with active cathodic contaminants such as iron, nickel, or graphite ... 

Lithium Carbon Batteries. These batteries are made in an hermetically sealed stainless-steel container with a metallic lithium anode, a Ketjen black carbon cathode, and a LiAlCl4 6SO2 electrolyte. The cathode composition is 96% Ketjen black and 4% Teflon. Teflon-rich carbon-coated nickel exmet is used as the cathode substrate. These batteries are made cathode-limited with the anode capaeity at least twiee the cathode capacity. Batteries are vacuum filled with the electrolyte. The open-eireuit voltage of the system is about 3.3 V. The average discharge voltage is 3.1 V at 1 mA/em. It is heheved that high-surface-area carbon forms a complex with the electrolyte, and this eomplex takes part in the cell reaction. 

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