对氟偶氮氯膦与铋显色反应的研究及应用

Study on the color reaction of bismuth with chlorophosphonazo-pF and its application

研究了 2 (4 氯 2 膦酸基苯偶氮 ) 7 (4 氟苯偶氮 ) 1,8 二羟基 3 ,6 萘二磺酸 (对氟偶氮氯膦 )与铋的显色反应。在0 2 6mol/L硝酸介质中 ,铋与对氟偶氮氯膦形成 1∶2的深蓝色络合物 ,最大吸收波长 664nm ,摩尔吸光系数为 1 2 0× 10 5,Bi 含量在 0～ 2 0 μg/ 2 5mL范围内符合比尔定律 ,方法操作简便 ,灵敏度高 ,选择性好 ,用于可锻铸铁中微量铋的测定 。

The color reaction of bismuth*#with chlorophosphonazo pF has been studied In 0 26mol/L HNO 3 solution,chlorophosphonazo pF can react with bismuth*#immediately at room temperature to form a deep blue complex with a maximum absorption at 664nm The composition of the complex is 1∶2(M∶L),and its apparent molar absorptivity is 1 20×10 5L·mol -1 ·cm -1 Beer's law is obeyed over the concentration range 0-20μg/25mL of bismuth This method has been applied to the determination of trace bismuth in iron sample with satisfactory results