钴镍存在下微量铜的光度测定法

Spectrophotometric Determination of Trace Copper in the Presence of Cobalt and Nickel

在pH值5的乙酸—乙酸钠溶液中,利用Co(Ⅱ)—PAN—CCl_4萃取溶液中的Cu(Ⅱ)时,形成在565nm具有最大吸收的Cu(Ⅱ)—PAN—CCl_4络合物,其表观摩尔吸光系数为ε_(565)=2.27×10~4。在有大量NaF存在下,方法不仅克服了钴和镍的干扰,还消除了基体铁对测定铜的影响,一般存在于钢铁中的合金元素不干扰铜的测定。文章拟定了钢铁中微量铜的测定方法,方法准确、简便、快速。

In HAc-NaAc solution ( pH5 ) ,when Co-PAN-CCl4 is used to abstract the Cu(II) in thesolution, it forms Cu-PAN-CCl4 complex vrhich has maximum absorption at 565 nm and' apparent molar absorptivity is 2.27X104. When exists a large amount of NaF, it eliminates not only the interference of cobalt and nickel, but also the influence of iron base in the determination of copper. The alloying elements that commonly exist in iron and steel do not interfere with the determination, the method is simple, convenient, accurate and quick.