0.1000g焦炭灰样品经氢氟酸-硝酸(1+3)溶液8 mL消解,用火焰原子吸收光谱法测定其中钾和钠的含量。钾和钠的质量浓度分别在4 mg·L-1及2 mg·L-1以内与其吸光度呈线性关系,检出限(3σ)分别为12 μg·L-1及6 μg·L-1。方法用于分析焦炭灰标准物质,测定值与认定值相符,钾和钠的相对标准偏差(n=11)依次在2.7%~3.8%和1.3%~3.1%之间。

Sample of coke ash (0.100 0 g) was digested with 8 mL of mixed acid of HF and HNO3 (1+3), and the contents of K and Na in the sample solution were determined by FAAS. Linear relationships between values of absorbance and mass concentration of K and Na were obtained in the ranges within 4 mg·L-1 and 2 mg·L-1, with detection limits (3σ) of 12 μg·L-1 and 6 μg·L-1, respectively. The proposed method was applied to the analysis of CRM′s, giving results in consistency with the certified values. Values of RSD′s (n=11) found were in the ranges of 2.7%-3.8% for K and 1.3%-3.1% for Na.