1-(5-硝基-2-吡啶偶氮)-2,7-萘二酚吸光光度法测定微量钴  

ABSORPTIOPHOTOMETRIC DETERMINATION OF TRACE AMOUNTS OF COBALT WITH THE NEW REAGENT 5-NO_2-PADN

作　　者：孙家娟[1] 白育伟[1] 刘彬[1] 王晓玲[1] 

机构地区：[1]咸阳师范学院化学系,咸阳712000

出　　处：《理化检验（化学分册）》2001年第9期394-396,共3页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

基　　金：陕西省教委科研基金资助课题 ( 94JK0 36)

摘　　要：报道了 1 (5 硝基 2 吡啶偶氮 ) 2 ,7 萘二酚与钴的显色反应 ,结果表明 ,在Tween 80存在下 ,pH 5 .2 6.5时试剂与钴形成稳定的蓝色配合物 ,其最大吸收波长位于 63 5nm ,表观摩尔吸光系数为 6.44× 10 4 L·mol- 1·cm- 1,配合物中钴与试剂的组成比为 1∶2 ,钴浓度在 0 5 μg/10ml范围内服从比耳定律。方法用于标准钢、金川精矿等试样中钴的测定 ,结果满意。A new reagent 1 (5 nitro 2 pyridylazo) 2,7 dihydroxynaphthalene (5 NO 2 PADN) is recommended for the determination of cobalt. It is shown that cobalt forms a stable blue complex with 5 NO 2 PADN in a solution of pH 5.2~6.5 in the presence of Tween 80. The absorption maxima of the complex lies at 635nm and the apparent molar absorptivity is 6.44×10 4L·mol -1 ·cm -1 . Beer′s law is obeyed in the concentration range of 0~5μg/10ml. The mole ratio of cobalt to 5 NO 2 PADN in the complex is 1∶2. The method has been applied to the determination of cobalt in standard samples of steel and ore with satisfactory results.

关 键 词：吸光光度法 钢 钴 1-(5-硝基-2-吡啶偶氮)2 7-萘二酚 矿物 测定 分析 

分 类 号：TG115.33[金属学及工艺—物理冶金] O614.812[金属学及工艺—金属学]