摘要
样品0.500 0~1.000 0g与活性炭0.15g和捕集剂氧化镁-氧化锌-碳酸钠(质量比为1∶2∶3)的混合物3g充分混匀,并于750℃焙烧1h,使样品中硒和碲分别生成各自的钠盐。加水50mL和几滴乙醇浓缩至25mL,定容至50mL。分取溶液10.00mL,加入3.6mol·L-1盐酸溶液7mL,加入掩蔽剂20g·L-1三氯化铁溶液1mL掩蔽干扰元素,于沸水浴中保持40min,冷却,定容至25mL作为测试溶液,用氢化物发生-原子荧光光谱法测定其中硒和碲的含量。硒和碲的质量浓度均在100μg·L-1以内与荧光强度呈线性关系,检出限(3s)分别为0.037,0.025mg·kg-1。按此方法测定了两种国家标准物质(GBW 07166和GBW 07234)中硒和碲的含量,标准值和认定值相符。
The sample (0. 500 0-1. 000 0 g) was mixed thoroughly with 0. 15 g of activated carbon and 3 g of a mixture of MgO, ZnO and Na2CO3 (mass ratio of 1 to 2 to 3) as collector. The mixture was roasted for 1 h at 750 ℃, to have the selenium and tellurium in the sample transformed to their sodium salt respectively. Water (50 mL) together with few drops of ethyl alcohol was added to the roasted residue, and the solution was then concentrated to 25 mL and finally diluted to 50 rnL. An aliquot of 10. 00 mL was diluted to 25 mL after addition of 7 mL of 3.6 mol · L^-1 HCl solution and 1 mL of 20 g · L^-1 FeCl3 solution (as masking agent for interfering elements), and keeping it in a boiling water bath for 40 min. Se and Te in the solution were then determined by HG- AFS. Linear relationships between values of fluorescence intensity and mass concentration of Se and Te were found in the same range within 100 μg · L^-1 , with detection limits (3s) of 0. 037, 0. 025 mg · kg^-1 respectively. The proposed method was used to determine Se and Te in 2 CRMrs of GBW 07166 and GBW 07234, giving results in conformity with the certified values.
出处
《理化检验(化学分册)》
CAS
CSCD
北大核心
2017年第1期64-67,共4页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)