微分电位溶出法测定PVC管材、管件中锡的方法研究

Study on Determination of Tin in PVC Pipes and Pipe Pieces by Differential Potentiometric Stripping Analysis

摘要: 目的建立一种测定PVC管材、管件中锡的方法。方法在0.03mol/L草酸介质中,于-11V预电解富集60s,记录-0.6V左右的溶出峰高。结果通过选择辅助电解质,解决了锡、铅的分离问题,通过加入表面活性剂提高了分析灵敏度。锡在0～400μg/L的浓度范围内呈现良好的线形关系(r=0.9960～0.9990),本方法的最低检测限为0.002mg/L,相对偏差3.49%～6.30%,回收率91.0%～98.6%。结论本法操作简单,灵敏度高,结果准确,可用于PVC管材、管件中锡的测定。

Abstract: ObjectiveTo establish a method of tin in PV Cpipes and pipe pieces.MethodsIn a medium of 0.03mol/L oxalic acid,the pre-electrolysis potential was-1.1V and time was 60s.The stripping peak is about -0.6V.ResultsT in and lead can be separated through selecting subsidiary electrolyte,increasing sensitivity of analysis by adding surface active agent.The method is suitable for deter mination of 0-400μg/L(r=0.996 0-0.999 0)tin.The lowest detecting limit、relative standard deviation and recovery rate of this method is 0.002mol/L、3.49 to 6.30 percent and 91.0 to 98.6 percent.ConclusionThis method is simple and can be applied in the examination of tin in PVC pipes and pipe pieces satisfactorily.