钙锶氯化物体系中钙和锶的重量法分析

针对氯化钙氯化锶混合体系,探索出能够准确分析该体系中钙和锶含量的分析方法。首先,用碳酸盐重量法分别对氯化钙和氯化锶单盐溶液进行分析,能够获得比较准确的测定结果且确定了碳酸盐沉淀适宜的烘干温度和烘干时间分别为200 ℃和20 h。在此基础上,结合碳酸盐重量法和经典的氯化银重量法对氯化钙和氯化锶的混合溶液进行准确地分析,分别获得碳酸盐沉淀的总质量和总氯的物质的量,再通过联立方程组求解得到钙锶氯化物共存体系中各组分的含量。最后,将实验方法用于分析钙和锶物质的量之比YB(YB=nCa∶nSr)为49、9.4、0.98、0.10和0.030的氯化物体系中氯化钙和氯化锶的组分含量时,测定结果比较准确,绝对误差小于0.5%。

Gravimetric analysis of calcium and strontium in calcium and strontium chloride system

The accurate analysis method of calcium and strontium content in mixed system of calcium chloride and strontium chloride was investigated. Firstly, the single calcium chloride and strontium chloride solution was analyzed by carbonate gravimetric method, respectively. The relatively accurate determination results could be obtained. Moreover, the proper drying temperature and time for carbonate precipitate were also obtained, i.e., 200 ℃ and 20 h. On the basis of this, the mixed solution of calcium chloride and strontium chloride was accurately analyzed by combining carbonate gravimetric method with classical silver chloride gravimetric method. The total mass of carbonate precipitate and the amount of substance of total chloride were obtained. Then, the content of each component in the chlorides system of calcium and strontium was calculated by simultaneous system of equations. Finally, the proposed method was applied to analysis of calcium chloride and strontium chloride in chloride system when the ratio of the amount of substance between calcium and strontium was 49, 9.4, 0.98, 0.10 and 0.030, respectively. The results were relatively accurate, and the absolute error was less than 0.5%.