GB132560A - - Google Patents

Abstract

132,560. Matheson, H. W. June 18, 1918. Mercuric oxide, obtaining; electrolytes, treating non-chemically; electrodes; liquid - electrode apparatus.-In the oxidation of mercury with a continuously agitated electrolyte, the violence of the agitation is periodically increased. A current density of about 55 amperes per sq. ft. of mercury surface is suitable, at 8-10 volts. An acid or alkaline electrolyte may be used, for instance a 3-10 per cent caustic soda solution. Two modifications of apparatus suitable for the process are shown in Figs. 1 and 4. As shown in Fig. 1, a cell is mounted on levelling-screws 31 bearing on blocks 30 which rest on insulators 29 and metal caps 28 surmounting pillars 27. The cell consists of an iron pan having ribs 13 to confine a layer of mercury and to support an insulating lining 14. Radiating cathode bars 22 project from a hub 19, and are joined by overlapping inclined blades 24. A stirrer 32, having inclined blades to give an up-anddown motion to the electrolyte, is situated above the mercury anode, and is rotatable at either of two speeds bv bevel-wheels 48, 47 connected to a shaft provided with a clutch. The electrolyte is admitted by a pipe 52, and mercury by a pipe 53 leading to a measuring-cup 54. A gauge glass 56 communicates with the electrolyte space and an outlet pipe 58. A hood is provided consisting of a cover 33, a back 35, and a front 36, which may be formed by a roller curtain. Upper and lower outlets 37, 38 are provided for light and heavy gases. In the modification shown in Fig. 4, the anode consists of an iron or nickel plate 61 embedded in the cement lining of the pan 11. The cathode 22 can be raised and lowered by cables passing round a drum 72 operated from a shaft 75. The mercury-measuring cup 54 is situated outside the cell and is connected therewith by a pipe 55. Specifications 132,557 and 132,559 [both in Class 2 (iii), Dyes &c.], are referred to.