石墨炉原子吸收光谱法直接测定城市污泥中有机态镉

Direct Determination of Organic Cadmium in Sewage Sludge by Graphite Furnace Atomic Absorption Spectrometry

建立了真空冷冻干燥法制备有机相标准系列,氯化钯-磷酸氢二钾作基体改进剂,分步斜坡升温石墨炉原子吸收光谱法直接测定城市污泥中痕量有机态Cd的方法,有效地消除了基体干扰。方法的精密度(RSD,n=11)为5.7%,用于污泥样品的测定加标回收率在91%—107%之间,与常规消解法测定值比较结果令人满意。

A method for direct determination of trace organic Cd in sewage studge by graphite furnace atomic absorption spectrometry was proposed. Freezing vacuum-desiccation was used to prepare the organic standard solution in this method with PdCl2-K2HPO4 as matrix modifier and stepslope method as program of temperature elevation to eliminate the matrix interferences effectively. The precision （RSD, n=11 ） is 5. 7% and recovery rate is 91%-107 % when the method was applied to the determination of sewage sludge. The results were satisfactory compared with those obtained from regular method.