容量法测定石膏中三氧化硫的研究

重量法是测定石膏中三氧化硫(SO3)的经典法,准确度高,适应范围广,但其效率低下,不适用于大量检测任务及现场检测.为此,本实验用过量的氯化钡溶液沉淀硫酸根离子,然后用乙二胺四乙酸二钠盐(EDTA)标液快速滴定溶液中剩余的氯化钡溶液,间接得出了SO3的含量.通过与重量法测试结果对比表明,EDTA容量法测定结果绝对误差小于1%,相对误差可保持在0.5%以下.此操作方法可提高石膏中SO3的测定速度,且不受其他因素干扰,简便可靠,是较理想的测定方法.

Volumetric Determination of Sulfur Trioxide in Gypsum

The gravimetric method is a classical method for the determination of sulfur trioxide ( SO3) in gypsum, and it has high accuracy and wide range of application.However, it is not suitablefor a large number of testing tasks and field test due to the low efficiency.In this study, the sulfate ion was precipitated with excess solution of barium chloride, and then the remaining barium chloride solution was titrated by EDTA instantly.In this way, the content of SO3 was obtained indirectly.Compared with the gravimetric method, the absolute error of the volumetric method is less than 1%, and the relative error can be kept below 0.5%.Therefore, this method can enhance the determination speed of SO3 in gypsum without the interference of other factors.The developed method is simple and reliable, and provides an ideal method for determinationof SO3 in Gypsum .