摘要
采用一种选择性好、灵敏度高的显色剂--苦胺酸偶氮变色酸,建立了测定铝合金中微量钴的分光光度法.在有氟化钠存在下及pH 11的氢氧化铵-氯化铵缓冲溶液中,钴与显色剂形成的络合物最大吸收峰在650 nm处,表观摩尔吸光系数ε=3.1×104.在25 mL溶液中,0～50μg钴(Ⅱ)服从比尔定律.该法测定钴的选择性好,用于铝合金样品的测定,相对标准偏差为2.2%,回收率在95%～105%之间.
A new color reagent picramazochrom, which is very sensitive and excellent selective is adopted to establish a spectrophotometric determination of microcobalt in aluminium alloy samples. In NH3·H2O- NH4C1 buffer solution at pH 11 and in the presence of NaF, the maximum absorption wavelength of the complex formed by cobalt and picramazochrom is at 650 nm and an apparent molar absorptivity is 3.1 × 10^4 L·mol^-1·cm^-1. Beer＇s law is obeyed in the range of 0 - 50μg/25mL for Co（Ⅱ）. The method has been successfully applied to the determination of cobalt in aluminium alloy samples. The relative standard deviation is 2.2 %, and the recovery is 95.3 % and 100.8 %, respectively. The results of the experiment are very satisfactory.
出处
《冶金分析》
EI
CAS
CSCD
北大核心
2005年第4期43-45,共3页
Metallurgical Analysis
