氯化钠-十六烷基三甲基溴化铵体系分离富集-原子吸收光谱法测定湖泊沉积物中的镉

建立了碘化钾存在下氯化钠-十六烷基三甲基溴化铵体系分离富集-原子吸收光谱法测定湖泊沉积物中镉的新方法,最佳浮选分离条件为0.1mol.L-1HNO3、0.05mol.L-1KI、5.0×10-3mol.L-1CTMAC,NaCl用量为1.0%(W/V)。在最佳浮选分离条件下,镉的浮选率在94.1%—99.2%之间。合成样分离试验表明,体系能定量分离镉,而大量基体元素不被浮选。富集试验结果显示本法具有较好的富集效果,可明显提高测定的灵敏度。应用本法对湖泊沉积进行分离测定,结果满意。

Determination of Cadmium in Lake Seiment by Atomic Absorption Spectrometry After Separation and Preconcentration by Sodium Chloride-Cetyltrimetheylammonium Bromide System

The novel method for the determination of cadmium in lake seiment by sodium chloride-cetyltrimetheylammonium bromide flotation separation and preconcentration system-atomic absorption spectrometry in the present of potassium iodide was established,and the optimal flotation separation conditions were obtained as follows:hydrogen nitrate concentration of 0.1mol·L-1,potassium iodide concentration of 0.05mol·L-1,CTMAC concentration of 5.0×10-3mol·L-1 and sodium chloride dosage of 1.0%(W/V).Under the optimal conditions,the flotation rate of cadmium was in the range of 94.1%—99.2%.The separation results of the synthetic samples showed that the system can quantificationally separated cadmium,but a large number of matrix elements not.The preconcentration results showed the method had relatively good preconcentration,and that can obviously improved the sensitivity of measurement.The method can be applied to separate and determine the lake seiment with satisfaction results.