本文研究了以铅离子选择电极为指示电极,电位滴定法测定氯化稀土中微量硫酸根的测定条件,找到了较好的滴定体系(80%丙酮-水溶液体系),在分离干扰离子RE~(3+)和Cl~-方面,采用银型和氢型阳离子树脂,实现了RE~(3+)、Cl~-正负干扰离子一次同时分离,获得满意的分离效果,按本文拟定的实验方法,测定下限可达到1×10~(-5)摩尔硫酸根(可测定氮化稀土中0.01%以上的硫酸根)。 In this paper, the determination of trace sulfate in the rare earth chloride by potentiometric titration was studied using the lead ion selective electrode as the indicator electrode. A better titration system (80% acetone-water system) 3+) and Cl ~ -, silver ions and hydrogen-type cationic resins were used to achieve simultaneous separation of RE ~ (3 +) and Cl ~ - positive and negative interfering ions at the same time. Satisfactory separation results were achieved. According to the experimental method , The lower limit of determination of up to 1 × 10 ~ (-5) mol sulfate (measurable rare earth nitrides 0.01% or more sulfate).