Dissolution method with HBr-Br2 for the analysis of Mn-Rh alloys by inductively coupled plasma-optical emission spectrometry

A new dissolution method of a Mn-Rh alloy including trace amounts of Al and Si has been developed for the precise analysis by inductively coupled plasma-optical emission spectrometry (ICP-OES). For the determination of Mn, Rh, Al and Si in Mn-Rh alloy samples (100 mg), the samples were dissolved with 20 ml of HBr-Br2, followed by the addition of 20 ml of HClO4 at room temperature; then, most of HBr was decomposed into Br2 with drops of H2O2. The resulting solution was concentrated to about 10 ml after the addition of 10 ml of HNO3, and MnO2 was decomposed with H2O2 after adding 10 ml of HCl (1+1) and 10 ml of H2O to obtain a clear solution. Si was determined by a gravimetric method. Moreover, after being measured by ICP-OES, the analytical results were estimated with the sequential correction method.