论文部分内容阅读
不含釩之高铬钢中铬的测定,一般文献介紹多采用硫—磷混合酸,或王水溶解试样。不溶解的炭化物以濃硝酸氧化并蒸发冒三氧化硫白烟而进行分解,然后将Cr~(+3)氧化成Cr~(+6),用直接滴定法或回滴法測定铬的含量。这些方法,在分析时间上一般都得40分钟以上,滿足不了炉前分析的要求。为了提高溶样速度,我們試驗了多种溶样方法:一份硝酸与一份盐酸;一份硝酸与二份盐酸;一份硝酸与三份盐酸;硫磷混合酸;过氧化氫与盐酸。认为
Determination of chromium in non-vanadium high chromium steel, the general literature describes the use of sulfur-phosphorus mixed acid, or aqua regia samples. Insoluble carbides are oxidized with concentrated nitric acid and evaporated to take white smoke of sulfur trioxide for decomposition. Then Cr ~ (+3) is oxidized to Cr ~ (+6), and the content of chromium is measured by direct titration or back drop method. These methods, in the analysis of time generally have more than 40 minutes, can not meet the requirements of the furnace analysis. In order to improve the speed of the sample, we tested a variety of dissolution methods: a nitric acid and a hydrochloric acid; a nitric acid and two hydrochloric acid; a nitric acid and three hydrochloric acid; phosphoric acid; hydrogen peroxide and hydrochloric acid. think