A direct determination method of Cd in titanium dioxide by flame atomic absorption spec-trometry was established after dissolution of sample with HF. HNO3 was used for dissolution of salts in the sample and removal of the residual HF. The sample dissolution conditions, acid dosage and the interference of matrix and coexisting elements were discussed. It was found that, the coexisting elements in TiO2 matrix and titanium dioxide at the highest content did not interfere with the determination of cadmium under the selected experimental conditions. The linear range of method was 0. 02-2. 0 μg/mL, the detection limit was 0. 003 3 μg/mL, and the lower limit of quantitation was 0. 011 μg/ mL. The proposed method was applied to the determination of actual sample, and the results were consistent with those obtained by inductively coupled plasma mass spectrometry. The relative standard deviation (RSD, n = 11) was smaller than 1 %, arid the recoveries were 98 %-103 %.%采用氢氟酸消解样品,硝酸溶解盐类并驱除氢氟酸,建立了火焰原子吸收光谱法直接测定钛白粉中镉的方法.对溶样条件、酸用量、基体及共存元素的干扰等进行了讨论.结果表明,在选定的实验条件下,二氧化钛基体和钛白粉中各共存元素在最高含量时均不干扰镉的测定.方法线性范围为0.02～2.0μg/mL,检出限为0.003 3μg/mL,测定下限为0.011μg/mL.将本方法应用于实际样品分析,测定结果与电感耦合等离子体质谱法基本一致,相对标准偏差在1％以下(n=11),回收率在98％～103％之间.
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