火焰原子吸收光谱法测定镍基体料炉渣中锰

采用盐酸-硝酸-氢氟酸-高氯酸分解试样,若试样还不能溶解完全,则再加5 mL硝酸冒烟至棕红色烟雾消失,加水微沸溶解,再用高氯酸调节pH值至0.5,采用火焰原子吸收光谱法(FAAS)进行测定,建立了镍基体料炉渣中锰的测定方法。在选定仪器条件下,锰的质量浓度与吸光度呈良好的线性关系,特征浓度和精密度符合检测要求,线性回归方程为Y＝0.170 1X+0.015 33,相关系数r＝0.999 3,方法检出限为0.003 4 mg/L。干扰试验表明:试样中共存元素对测定不产生干扰。将实验方法应用于5个不同锰含量水平的镍基体料炉渣中锰的测定,结果与GB 11906—1989标准方法基本一致,相对标准偏差(n=11)在0.9%～1.5%之间;对测定结果进行格拉布斯检验,结果表明11次平行的结果无异常值。方法回收率在97%～98%之间。

Determination of manganese in slag of nickel matrix material by flame atomic absorption spectrometry

The sample was decomposed with hydrochloric acid-nitric acid-hydrofluoric acid-perchloric acid. If the sample was not completely dissolved, 5 mL of nitric acid was added and heated until the brown red fume disappeared. The residue was dissolved in water under slight boiling conditions. Then, the pH value of solution was adjusted with perchloric acid to 0.5. The content of manganese was determined by flame atomic absorption spectrometry (FAAS).Thus,a determination method of manganese in slag of nickel-based materials was established. The mass concentration of manganese showed good linearity to the absorbance under the selected instrumental conditions. The characteristic concentration and precision could meet the detection requirements. The linear regression equation was Y＝0.170 1X+0.015 33 with correlation coefficient of R＝0.999 3. The detection limit of method was 0.003 4 mg/L. The interference test indicated that the coexisting elements in sample had no interference with the determination. The proposed method was applied to the analysis of five actual samples for slay of nickel matrix material with different manganese content, and the results were consistent with those obtained by standard method GB 11906—1989. The relative standard deviations (RSD, n=11) were in range of 0.9%-1.5%, The determination results were verified by Blas inspection. It indicated that there were no abnormal value for eleven parallel determination. The recoveries were between 97% and 98%.