钢铁及纯金属中硫的测定,国内外大都采用燃烧法,这类方法比较快速,它的主要缺点是在高温下,试样中硫转化为二氧化硫的作用并不完全,在通常的燃烧条件下,硫的回收率都小于90%,必须依靠同类标样作为基准进行换算。这就在精确分析中,尤其是在第一代标样的分析中受到了限制。另外,燃烧时使用的坩埚,它们的空白值比较高,对微量硫的测定,即使配合上库仑滴定和红外线分析,灵敏度的提高也存在较大困难。硫化氢发生——次甲基蓝比色法准确度较高,选 Determination of sulfur in steel and pure metal, most of the combustion method used at home and abroad, this method is relatively fast, its main drawback is that under high temperature, the role of sulfur in the sample into the sulfur dioxide is not complete, under normal combustion conditions , Sulfur recovery rate of less than 90%, must rely on the same standard as a benchmark for conversion. This is limited in the precise analysis, especially in the analysis of the first generation of standards. In addition, the crucibles used for combustion have relatively high blank values, and the measurement of trace sulfur has great sensitivity in improving the sensitivity even in combination with coulometric titration and infrared analysis. Hydrogen sulfide occurs - Methylene blue colorimetric high accuracy, selection