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锑的容量法测定一般都沿用经典的硫酸铈和溴酸钾容量法,此法须在70—80℃下,在20%盐酸介质中滴定。如试样中含铁量高时,用甲基橙作指示剂,终点不明显。本文研究了在0.5—2M硫酸溶液中,以铁(Ⅱ)为诱导剂(使铁(Ⅱ)和锑(Ⅲ)的摩尔比>1:1)的容量法,从而确立了二苯胺磺酸钠为指示剂,用重铬酸钾标准溶液滴定锑的条件,终点敏锐。砷对滴定虽有干扰,但在测定条件下,砷(Ⅲ)与重铬酸钾不是定量反应.试样中砷含量在5%以下,对锑的测定无影响。试样中含有铁(Ⅱ),经与硫酸-硫酸钾高温熔矿
The volumetric method for the determination of antimony generally follows the classical volumetric method of cerium sulfate and potassium bromate, which is titrated in a 20% hydrochloric acid medium at 70-80 ° C. Such as high iron content in the sample, methyl orange as an indicator, the end is not obvious. In this paper, the capacity of iron (Ⅱ) as an inducer (molar ratio of iron (Ⅱ) and antimony (Ⅲ)> 1: 1) in 0.5-2M sulfuric acid solution was studied. As indicator, with potassium dichromate standard solution titration antimony conditions, the end point sensitive. Although arsenic did not interfere with titration, arsenic (Ⅲ) and potassium dichromate were not quantitatively determined under the conditions of determination, and the arsenic content in the sample was below 5%, which had no effect on the determination of antimony. The sample contains iron (II), after the high-temperature melting with sulfuric acid - potassium sulfate