鉄鋼中のヒ素定量方法

抄録

Because the distillation method for determination of arsenic needs a very long time and is also tedious, the SnCl₂ reduction method has been developed to save the time required for the analysis. This procedure is most widely used for the determination of arsenic in iron and steel. In this process, SnCl₂ is added to a solution of AsO₄^3- in 8N HCl medium. The solution is heated at 90°C for 30 minutes and metallic arsenic obtained is determined by titration with N50 I₂ and N 50 Na₂S₂O₃. Inaccurate results are often obtained in the determination of arsenic by this technique, because of the high temperature, and the influence of titanium.
This paper reports the results of experiments using the SnCl₂ with 12N HCl medium at 45°C for reduction of the arsenic. In using this method the author has devised an improvement in technique which renders the method more certain.