One-step microwave digestion procedures for the determination of aluminium in steels and iron ores by inductively coupled plasma atomic emission spectrometry

Abstract

The use of microwave ovens for the dissolution of samples is widespread and has made it possible to obtain results very rapidly giving precision and accuracy identical with, or better than, than that obtained by classical procedures. Technical publications and instruction manuals, however, rarely give information on the dissolution of insoluble compounds in acids such as, for example, compounds of aluminium the determination of which in iron and steel is important in iron and steel industrial laboratories. Procedures are proposed for the dissolution of aluminium in iron ores and steels; the procedures were tested using certified reference materials. For steels, dissolution is accomplished far faster than with classical procedures. Preliminary dissolution tests on pure alumina, under controlled temperature and pressure conditions, were necessary in order to determine the optimum conditions for the dissolution of iron ores. Complete dissolution of an iron ore sample takes approximately 90 min.