利用铬黑T分光光度法快速测定硅酸盐中的铝

Spectrophotometric Determination of Trace Aluminium in Silicate Samples with Calcochrome Black T

研究了Al3 + 与铬黑T显色反应的影响因素 ,对硅酸盐试样中大量存在的钙的干扰 ,采用加入EGTA进行掩蔽。Al3 + 量在 0～ 0 8μg/mL内符合比耳定律 ,其表观摩尔吸光系数为 2 1× 10 4 ,回归方程为A =0 0 0 0 74ρ(μg/mL) +0 0 6176 ,相关系数为γ =0 981。

The factors of reaction between calcochrome black T and Aliminium were studied.The method of the spectrophotometric determination of trace aluminium is found.The mole absorptivity coefficient is 2 1×10 4,and the Beer's law is obeyed in the 0～0 8μg/mL range of Al 3+ content.The regression equation of calibration graph is ΔΑ=0 000?74ρ(μg/mL)+0 061?76,with a correlation coeffcient of 0 981.This method is able to be used in the determination of trace aliminium in silicate samples.