双环己酮草酰二腙分光光度法测定铁矿石中铜

摘要

In the pH 9. 2 ~9. 3 ammonia buffer solution, bis( cyclohexanone) oxaldihydrazone ( BCO) formed blue complex compound with copper (Ⅱ) , and at the location of the maximum absorption wavelength of 600 nm, the absorbance and the copper concentration conformed to Lambert-beer law, and the copper’s mass fraction was calculated. The effects of the specimen’s decomposition, specimen amount, pH value, the amount of BCO, coloring temperature, coloring time, coexisting elements as well as different reference methods were studied. Within the scope of the copper content of 0. 015% ~0. 99%, the RSD of the method were 0. 46% ~3. 8%( n=5 ) , recovery rate was 97. 5% ~105. 0%.%在pH 9.2~9.3的氨性缓冲溶液中，双环己酮草酰二腙( BCO)与铜(Ⅱ)生成蓝色络合物，其在最大吸收波长600 nm 处吸光度与铜的浓度符合朗伯比尔定律，计算了铜的质量分数。考察了试样的分解、试料量、 pH值、双环己酮草酰二腙用量、显色温度及显色时间、共存元素以及不同参比法等对测定的影响。在铜含量0.015%~0.99%范围，方法的相对标准偏差(RSD)为0.46%~3.8%(n=5)，回收率为97.5%~105.0%。