摘要
提出了测定锡铅焊料中锡量的络合返滴定法。采用混合酸(盐酸-硝酸)溶解样品,加过量的EDTA络合锡、铅等元素。再用六次甲基四胺将溶液的pH调至5.5,以二甲酚橙为指示剂,用氯化锌标准溶液返滴与锡络合且释放出来的ED-TA,测得锡量。研究了溶解样品过程中盐酸与硝酸的体积比,酸度调节的方法,EDTA和水的用量,氟化钠的用量,杂质干扰对试验的影响。在优化的试验条件下,所测国家标准样品获得令人满意的结果,两个标准样品的回收率在99.76%～100.5%范围之内。
Complexometric back titration was brought up to the determination of stannum content in tin-lead solder.Sample was treated by hydrochloric acid and nitric acid.Superfluous EDTA was added for complexation with stannum,lead and other elements.Hexamethylenetetramine was used to keep acidity at pH 5.5.EDTA of stannum was titrated by standard zinc chloride solution at pH 5.5,with xylenol orange as indicator.Then stannum content was attained,Influential factors of diffluence process,including the volume ratio of hydrochloric acid and nitric acid,method of regulating acidity,quantity of EDTA and water added,quantity of sodium fluoride added,disturbance of element were studied.Under the optimum conditions,approving result of two model samples was acquired.The range of recovery was 99.76%～100.5%.
出处
《南昌航空大学学报（自然科学版）》
CAS
2011年第2期89-92,共4页
Journal of Nanchang Hangkong University(Natural Sciences)
关键词
络合返滴定法
锡铅焊料
锡量
complexometric back titration
tin-lead solder
stannum content
