【摘要】 在HNO3 介质中利用Cr2 O2 - 7氧化偶氮胂Ⅲ的褪色反应 ,对粉煤灰中的痕量铬进行测定。结果表明 ,在 3 2mol·L- 1 的硝酸介质中褪色反应具有高的灵敏度 ,反应产物的最大吸收波长为 52 0nm ,摩尔吸光系数为1 9× 1 0 6 L·mol- 1 ·cm- 1 。铬 (Ⅵ )含量在 0 0～ 40 0 μg·L- 1 范围内服从比耳定律。该法用于测定粉煤灰中的铬 ,得到了满意的结果。更多还原

【Abstract】 In HNO 3 medium the fading reaction of arsenazo Ⅲ oxidated with Cr 2O 2- 7 was used as to determine trace Cr in fly ash containing Cr. The results show that the fading reaction has high sensitivity in the medium of 3.2 mol·L -1 nitric acid, the molar absorptivity of 3.9×106 L·mol -1·cm -1 at 520 nm, and Beer′s law is obeyed for Cr(Ⅵ) in the range of 0.0～40.0 μg·L -1. Contents of Cr in fly ash were determined with satisfactory results.更多还原