不同前处理方法测定银锡焊料中3种重金属元素

选用银含量为3%、30%和70%的银锡焊料样品,分别经过三种不同前处理方法,采用硝酸、盐酸消解,应用电感耦合等离子体发射光谱法(ICP-OES)同时测定锡铅合金中镉、铅、汞3种重金属元素含量。实验研究了不同前处理方法对银锡合金中重金属测定的影响。实验表明消解实验中的共沉淀现象会对3种重金属元素的测定产生不利的影响,回收率不能满足要求;采用硝酸消解,过滤残渣经王水消解的方法,镉、铅、汞的7次测定重复性相对标准偏差在2.7%~5.5%、加标回收率在85.6%~103%,能够满足RoHS测试要求。

Determination of 3 heavy metals in silver-tin solder by different pretreatment methods

Samples with silver content of 3%, 30% and 70% were selected, and three different pretreatments were used for digestion by nitric acid and hydrochloric acid. Three heavy metals, such as cadmium, lead and mercury, were determined simultaneously by ICP-OES. The influence of different pretreatment methods on the analysis of heavy metals in silver-tin alloy was studied. Experiments show that the co-precipitation phenomenon in digestion experiments has adverse effects on the determination of three heavy metal elements, and the recovery rates cannot meet the requirements. The samples were first digested by nitric acid, Then the residue is digested by aqua regia. The recovery rates of cadmium, lead and mercury were in the range of 85.56%-102.98%.