示波滴定法连续测定锌合金中铝和铜

Successive determination of aluminium and copper in zinc alloy by oscillographic titrimetry

用示波滴定法连续测定锌合金中的铝、铜含量。试样经酸溶后 ,在 pH5 5的HAc NH4 Ac缓冲介质中 ,用Zn标准溶液连续示波滴定 ,NH4 F和硫脲分别置换A1 EDTA和Cu EDTA中的EDTA ,间接计算出Al和Cu的含量。该方法快速简便 ,终点直观 ,准确度、精密度均较高。标准加入回收率在 99 5 %～ 10 0 5 %之间。RSD <0 5 %。

In this paper,the successive determination of aluminum and copper in zinc alloy by oscillographic titration was studied After the sample dissolved,in the buffer solution of HAc NH 4Ac at pH5 5,EDTA demasked respectively from Al EDTA and Cu EDTA complex with the addition of fluoride and thiourea was suceessively titrated by oscillography with the standard solution of zinc The contents of aluminium and copper could be indirectly calculated The method has a good selectivity and high accuracy The recovery was 99 5%-100 5% and RSD was less than 0 5%