GB157785A - Electrolytic process and apparatus for the separation of platinum from other metals contained in platiniferous materials - Google Patents

Abstract

157,785. Slatineanu, E. Dec. 19, 1919, [Convention date]. Wet processes of recovering gold and palladium. -In the separation of platinum from other metals, there is obtained a solution containing also gold and palladium, which are then precipitated by means of hydrogen previously treated with ultra-violet light, for instance by passing the gas through a helical silica tube surrounding a silica mercury-vapour lamp. If a plate of gold or palladium is placed in the solution, a voltaic couple is stated to be formed with the hydrogen. In obtaining the solution of platinum, gold, and palladium, there may be employed broken ingots of impure platinum, or sludges resulting from electrolytic treatment of impure gold anodes in nitric acid solution, the silver being deposited on the cathode and platinum, iridium, palladium, gold, and lead precipitated. The impure metal or sludge may be treated with diluted aqua regia at 70‹ C. in a closed vessel A provided with a stirrer b. Only the platinum, palladium, and gold dissolve. An alternative method of obtaining such a solution consists in treating an impure gold anode in acid auric chloride solution or aqua regia, silver, iridium, rhodium, ruthenium, &c., remaining undissolved. A part of the gold may then be deposited electrolytically, say in the same cell. Treatment with the hydrogen is effected in a closed vessel B, excess of gas escaping by a pipe f, and the solution being removed by a pipe g extending downwards through one-third of the height of the vessel. Specification 154,213, [Class 1 (i), Chemical processes &c.], is referred to.