铝合金中微量铜的分光光度法测定

本文报道2—(5—硝基—2—吡啶偶氮)—5—二甲氨基苯甲酸(5—NO_2—PAMB)分光光度法测定微量铜。试剂与铜离子反应迅速,水溶性很好。配合物的表观摩尔吸光系数为8.04×10~4L.mol~(-1).cm~(-1)。络合比Cu:5—NO_2—PAMB=1:2,Cu~(2+)浓度在O～35μg/25mL范围内服从比耳定律。方法用于测定铝合金标样及金属铝中的铜,结果与标准值相符。标准加入回收率在99％～102％之间。

Spec trophotometric determination of micro amounts copper in aluminium metal sample

Spec tropho tome trie determination of micro amounts copper using a new chromogenic reagent 2-( 5-nitro-2-pyridylazo)-5-dimethylamih obenzoic acid (5-NO2-PAMB) is reported in this paper. The reagent has excellent solubility in water and can rapidly react with copper iron to form a coordination complex .The apparent molar absorptivity of coordination complex is 8.04x104L/mol .cm at 640nm.Cu:5-NO2-PAMB =1:2 Beers law isobeyed in the range of 0~25~gCu+2/25ml .This method has been appliedto determine copper in standard aluminium alloys and aluminium metal sample. The results accord with,the certified values.The recoveries for standard addition copper are among99%~102% .