二溴对甲基偶氮磺光度法测定铝合金中微量铅  

Spectrophotometric determination of micro lead in aluminium alloy with dibromo-p-methylsulfonazo

作　　者：高琳[1] 姚军龙[2] 晏高华[2] 

机构地区：[1]江汉大学化学与环境工程学院,湖北武汉430056 [2]湖北省机电研究设计院理化测试中心,湖北武汉430070

出　　处：《冶金分析》2005年第2期54-55,共2页Metallurgical Analysis

摘　　要：研究了新显色剂二溴对甲基偶氮磺与铅的反应,建立了直接测定铝合金中微量铅的光度分析方法。在0 6mol/L硝酸介质中,铅与二溴对甲基偶氮磺形成1∶2蓝色络合物,最大吸收波长630nm,表观摩尔吸光系数为9 05×104。在25mL溶液中,铅含量在0～50μg符合比尔定律。用于铝合金标样中铅的测定,相对标准偏差RSD为1 85%～4 02%,结果与标准值吻合。本法可用于铝合金中微量铅的直接测定。The chromogenic reaction between the new reagent dibromo-p-methylsulfonazo and lead(II) is studied. In 0.3 mol/L NHO3 medium lead reacts with the reagent to form a 1:2 blue complex, which exhibits an absorption maximum at 630 nm with a apparent molar absorptivity of 9.05 × 104 L·mol-1·cm-1. Beer's law is obeyed in the range of 0 - 50 μg for lead in 25 mL of solution. The results of determining lead by this method are consistent with certified value. The RSD is 1.85% - 4.02%.This method has been used to determine micro lead in aluminium alloys.

关 键 词：二溴对甲基偶氮磺 铝合金 微量铅 光度法测定 表观摩尔吸光系数 最大吸收波长 相对标准偏差 直接测定 光度分析 硝酸介质 比尔定律 显色剂 络合物 铅含量 RSD 标准值 溶液 

分 类 号：TG115.33[金属学及工艺—物理冶金]