Hill, U. T.
Senior staff chemist, Inland Steel Co., East Chicago, Ind.
Pages: 7 Published: Jan 1969
The determination of arsenic by the atomic absorption method is indicated generally in the literature of most instrument manufacturers. Attempts to determine arsenic by the recommended procedure, however, have not been successful. As early as 1959, L'vov in Russia and later Massman in Germany investigated the determination of arsenic by the atomic absorption method and concluded that due to the almost complete absorption of the arsenic resonance line by products of acetylene combustion at 1937.6 Å the determination by conventional techniques was not possible. The introduction of electrically heated vaporizing techniques in an argon atmosphere suggested in these studies introduced involved instrumentation and is a departure from the conventional atomic absorption method. This study was undertaken to retain, if possible, the simplicity of the flame absorption method and meet the requirements of accuracy needed in metallurgical analysis for arsenic. It was found possible to overcome background absorption by changing to the 1890.4 Å line and the use of nitrous oxide flame. Also by precipitating the arsenic as the magnesium arsenate by the Weisz oven ring method a determination of arsenic could be made by determining the magnesium. With the introduction of the hydrogen argon flame, however, it became possible to determine arsenic with great accuracy at 1937.6 A following a rapid distillation procedure previously developed for a photometric method. Thus, it became possible to determine arsenic in all types of metallurgical products including iron ores, carbon, and high-alloy steels with accuracy equal to the photometric method.
atomic absorption, arsenic, steel, iron ores, spelter, analyzing
Paper ID: STP47274S