METHOD OF A SOLUTION TREATMENT FOR THE OSCILLOPOLAROGRAPHIC DETERMINATION OF ARSENIC AND ANTIMONY IMPURITIES IN HIGH-TIN ALLOYS

A method for the determination of arsenic and antimony impurities in h igh-tin alloys has been developed. Rapid analysis is possible using ef ficient co-reduction of As(V) and Sb(V) with 0.05 g of hydroquinone an d 0.2 ml of 46 % hydrobromic acid with simultaneous extraction by benz ene from 9 M sulfuric acid. Simultaneous extraction of tin is excluded under these conditions. Each element is determined by the oscillopola rographic method in a separate aliquot of the benzene layer against di fferent backgrounds. Arsenic and antimony may be determined at a 400-f old or greater excess of tin. Excess arsenic should not exceed the ant imony content by more than 30-fold, and excess antimony may not exceed the arsenic content by more than 20-fold.