Method for separating precious metals from solutions of thiourea with hydrochloric acid

Abstract

The subject of the application is a method for separating precious metals contained in solutions of thiourea in hydrochloric acid consisting in the precipitation of selective concentrates and precipitates of individual metals, characterized in that a nickel cementing agent is introduced into the eluate of thiourea in hydrochloric acid containing gold, palladium, platinum and rhodium in the amount of <200 mg / dm3 of each metal, the whole is mixed at a temperature of 20°C - 30°C for 60 minutes and then filtered, then a copper cementing agent is introduced into the solution obtained after filtration in the amount of 60 g per 1 dm3 of the filtered solution, the mixture is mixed at a temperature of 20°C - 30°C for 60 minutes and then filtered, then a precipitation agent in the form of a 30% hydrogen peroxide solution (H2O2) in the amount of 60 cm3 per 1 dm3 of the filtered solution is introduced into the solution obtained after filtration dm3 of the filtered solution, the whole is stirred at a temperature of 20°C - 30°C for 60 minutes,then filtered, then a zinc cementing agent is added to the solution obtained after filtration in the amount of 30 g per 1 dm3 of the filtered solution, the whole is mixed at a temperature of 20°C - 30°C for 60 minutes, then the Zn-Rh concentrate is filtered,