用二溴对甲基偶氮溴磺新显色剂光度法测定铝合金中微量铅  

Spectrophotometric determination of micro lead in aluminium alloys with a new chromogenic reagent dibromo-p-methyl-bromosulfonazo

作　　者：吴岚[1] 常江[1] 潘教麦[1] 

机构地区：[1]华东师范大学化学系,上海200062

出　　处：《冶金分析》2002年第6期7-8,6,共3页Metallurgical Analysis

摘　　要：研究了在酸性介质中,新显色剂二溴对甲基偶氮溴磺与铅的显色反应。在3mol/L的磷酸介质中,显色剂与铅 形成2∶1的稳定的蓝色络合物。其最大吸收波长为640nm,表观摩尔吸光系数ε=1 06×105,铅含量在0～25μg/25mL范围内符合比尔定律。大多数金属离子的允许量在毫克量级。拟定的方法用于铝合金中微量铅的测定,结果令人满意。The color reaction of a new reagent dibromopmethlybromosulfonazo(DBMBSA)with lead in acid medium was studiedIn 3mol/L H3PO4 medium,DBMBSA reacts with Pb*'to form a stable blue complex(2∶1 by mole) with absorption maximum at 640nmIts apparent molar absorptivity is found to be of 106×105L·mol-1·cm-1Beer's law is obeyed in the range of 0-25μg Pb/25mL Most of foreign ions in mgamount do not interfere with the reactionThe proposed method has been applied to the determination of micro lead in aluminium alloys with satisfactory results

关 键 词：显色剂 测定 二溴对甲基偶氮溴磺 铅 铝合金 光度法 

分 类 号：TG115.3[金属学及工艺—物理冶金]