催化动力学光度法测定煤矸石中痕量钼

Determination of Trace Molybdenum in Coal Gangue by Catalytic Kinetic Spectrophotometry

研究了在HCl介质中 ,Mo(Ⅵ )催化盐酸肼还原劳氏紫使之褪色的新指示反应 ,确定了催化褪色反应测定Mo(Ⅵ )的动力学条件 ,建立了测定痕量Mo(Ⅵ )的新方法。方法的表观摩尔吸收系数为 1 .4× 1 0 5L·mol- 1 ·cm- 1 ,线性范围为 0～ 35 0 μg/L ,检出限为 6.2× 1 0 - 1 1 g/L ,6次测定的RSD≤ 5 % ,加标回收率为 96.0 %～ 1 0 6.7% ,已用于测定煤矸石中的痕量Mo(Ⅵ )。

A catalytic decolorizing spectrophotometric method for the determination of trace Mo(Ⅵ) has been developed. The method is based on the catalytic effect of Mo(Ⅵ) on the reduction of Lauth's violet with hydrazine hydrochloride in hydrochloric acid medium. The kinetic condition on reaction rate has been studied. The molar absorbance is 1.4×10 5?L·mol -1 ·cm -1 . The detection limit for Mo(Ⅵ) is 6.2×10 -11 ?g/L with linear range of 0～350?g/L. The recovery of standard addition is 96.0%～106.7% with precision of ≤5% RSD( n =6). The method has been applied to the determination of trace Mo(Ⅵ) in coal gangue .