Influence of Arsenic on the Analysis of Iron and Steel (Part 2). On the Determination of Copper and Manganese

Abstract

Following the first report of this series, the influences of arsenic on the determination of copper or manganese in iron and steel were studied. On the determination of copper there was no influence in sodium hyposulfite separation method or hydrogen sulfide separation method, directly. But in the procedure of hydrogen sulfide separation, the amounts of iron coprecipitated with sulfides became larger by the presence of arsenic, and so the reprecipitation of Fe(OH)3 to remove iron was necessary. There was no interference of arsenic with the determination of manganese by any method, such as, titration method with ammonium ferrous sulfate-potassium permanganate or with ammonium ferrous sulfate indicated its end point by diphenylamine or with sodium arsenite, after oxidation by ammonium persulfate.