環境試料中のクロム分析における前処理方法の検討

抄録

In most of chromium determination practices, acid extraction using hydrochloric acid, nitric acid, or sulfuric acid and nitric acid has been applied for environmental samples. Since chromium and most of its oxides are insoluble in acid, total chromium cannot be determined by the conventional pretreatment. The conventional acid extraction technique and alkali fusion technique, which was considered to completely recover chromium, were compared using chromium sesquioxide as a test compound. The alkali fusion treatment with sodium carbonate completely isolated chromium from chromium sesquioxide, while acid extraction using hydrochloric acid, etc., isolated little, even by addition of hydrogen peroxide solution. The acid extraction of collected dust and atmospheric dust gave a much lower chromium level than the alkali fusion. Thus, the alkali fusion technique using sodium carbonate, etc., is concluded to be one of the most suitable methods for the pretreatment of chromium determination of environmental samples.