1965 Volume 14 Issue 3 Pages 206-211
A study is described for the separation and concentration of various metals from an aqueous solution by carrier precipitation with copper sulfide using radioisotope as a tracer. One milligram of copper (II) and 0.06-0.1 ml of 1 M sodium sulfide solution are added to 20-50 ml of solution containing μg quantities of metals, and the distribution of μg amounts of metal is investigated by measuring the radioactivity in liquid phase or solid phase (precipitate) .
Gold, silver, mercury, platinum and copper are collected completely from 0.1-1.0 N hydrochloric acid solution, whereas cobalt, thallium and zinc are retained in solution.
The increase of pH above 9.0, however, enhances the recovery of cobalt and zinc up to>90%.
The recovery is not affected by the difference of carrier or the method or rate of precipitation. Though the presence of chloride ion (<25%) does not decrease the recovery, the presence of complexing reagents of trace metals diminishes the recovery remarkably.
The treatment of copper sulfide precipitates is demonstrated by several methods. This procedure has effectively been applied to the separation and concentration of traces of gold, silver or mercury in copper, lead, zinc, nickel and manganese.