非离子表面活性剂Tween-80存在下5-Br-PADAP分光光度法测定微量Cu(Ⅱ)和Ni(Ⅱ)

SIMULTANEOUS DETERMINATION OF CuⅡAND NiⅡIN THE PRESENCE OF TWEEN-80 BY 5-Br-PADAP SPECTROPHOTOMETRY

在pH 3.50酸性介质中 ,Cu 和Ni 在非离子表面活性剂Tween - 80存在下 ,与5-Br-PADAP生成有色配合物 ,其最大吸收波长位于 575nm处 ;表观摩尔吸光系数分别为7.97× 10 4 L·mol- 1 ·cm- 1 和 1.0 2× 10 5 L·mol- 1 ·cm- 1 ;Cu 在 0～ 0 .52mg·L- 1 ;Ni 在0～ 0 .4 8mg·L- 1 范围内符合比耳定律 .用拟定的方法测定了钢样中的Cu 和Ni 含量 ,结果令人满意 .

Under the acid medium of pH?3.50,Cu? and Ni? can form colored complexes with 5-Br-PADAP and both maximum absorption wavelength are at 575?nm,the apparent molar absorption coefficient are 7.97×10 4?L·mol -1 ·cm -1 and 1.02×10 5?L·mol -1 ·cm -1 .Beers law is obeyed for Cu? and Ni? in the range of 0～0.52?mg·L -1 and 0～0.48?mg·L -1 respectively.The content of the Cu? and Ni? in the steel samples were determined,the result of which is quite satisfactory.