Studies of the separation of trace metals by the manganese dioxide “collection” method. Part III. The behaviour of copper and zinc. Further studies of the behaviour of lead and tin: the determination of lead and tin in copper-base alloys

Abstract

Studies of the collection of copper and zinc by co-precipitation with manganese dioxide are reported. The collection of copper is shown to be small under all conditions studied; that of zinc is negligible.

Further studies of the collection of lead and tin are presented, and a method for their separate and simultaneous determination is described. The virtual non-collection of copper and zinc is used as a basis for the application of these methods to the determination of lead and tin in copper-base alloys. The collection of lead and tin is made from a 0·008 M acidic solution containing ethanol to hold the tin in solution. After dissolution of the precipitate, tin and lead are determined together by polarography in acidic chloride solution. Lead is then determined alone by polarography in alkaline mannitol solution and the tin content found by difference.

Results are presented and some aspects discussed.