热分解齐化原子吸收光度法测定废水中的总汞

Determination of Total Mercury in Wastewater with Thermal Decomposition Atomic Absorption Spectrophotometry

建立用热分解齐化原子吸收光度法测定废水中总汞的方法。将样品加热至650℃，使所有汞转化成蒸气，利用催化管将蒸气中的二价汞转化成零价汞，再利用金管捕集零价汞，加热金管释放零价汞并使其进入分析单元，在253．7 nm处以冷原子光谱法测定汞含量。方法检出限（ tS）为0．045μg／L，测定下限为0．180μg／L。相对标准偏差RSD为2．3％～4．6％，加标回收率P为86．2％～94．8％。用热分解齐化原子吸收光度法直接测定废水中总汞，操作简单，污染小，毒性低，可替代《水质总汞的测定冷原子吸收分光光度法》（ HJ 597－2011）。

Established a method measuring total mercury in wastewater by thermal decomposition atomic absorption spectropho -tometry.The samples were heated to 650℃to transform all the mercury into vapor , catalytic tube was used to transform diva-lent mercury in the vapor into zero -valent mercury , then the zero-valent mercury was trapped into a gold tube , then the gold tube was heated to release the zero -valent mercury and released it into analyzing unit , finally, the content of mercury was de-termined with the cold atomic spectrometry at 253.7nm.For this method, the detection limits （tS） was 0.045 μg/L and the lower limits of determination was 0.180 μg/L.Values of RSD was ranged form 2.3% to 4.6%.Recovery rate was ranged from 86.2%to 94.8%.Detected total mercury in wastewater directly by thermal decomposition atomic absorption spectropho -tometry method, it can substitute the standard method cold atomic absorption spectrophotometry HJ 597-2011 due to it ’ s simple operation , less pollution , lower toxicity .