石墨炉原子吸收光谱法测定化学镀镍液中痕量铅

通过对干燥、灰化、原子化等程序的时间和温度进行优化试验,以5 mL 50 g/L磷酸氢二铵溶液为基体改进剂,采用石墨炉原子吸收光谱法测定了化学镀镍液中铅的含量。确定了仪器最佳工作条件如下:干燥温度为120 ℃,干燥时间为20 s(其中,升温时间为10 s,保持时间为10 s);灰化温度为800 ℃,灰化时间为20 s;原子化温度为1 600 ℃,原子化时间为3 s。铅含量在10.0～50.0 μg/L范围内与吸光度呈良好的线性关系,其相关系数(R²)为0.998 5,方法检出限为0.81 μg/L。采用实验方法对自制化学镀镍液中铅平行测定6次,测得结果与理论值的相对误差在4.0%～5.5%之间,相对标准偏差(RSD)不大于4.3%,加标回收率在97%～103%之间。

Determination of trace lead in electroless nickel plating solution by graphite furnace atomic absorption spectrometry

Time and temperature were optimized in each drying, ashing, atomization and other procedure. With 5 mL of 50 g/L ammonium phosphate as matrix modifier, lead in electroless nickel plating solution was measured by graphite furnace atomic absorption spectrometry. The optimum working conditions of instrument were identified: drying temperature of 120 ℃, drying time of 20 s (heating time of 10 s and heat preservation time of 10 s), ashing temperature of 800 ℃ and ashing time of 20 s, atomization temperature of 1 600 ℃ and atomization time of 3 s. Excellent linear relationship existed between 10.0-50.0 μg/L lead and absorbance. Its correlation coefficient (R²) was 0.998 5 and detection limit was 0.81 μg/L. Lead in the self-made electroless nickel plating solution was tested for 6 times. The relative error of tested result and theoretical value was 4.0%-5.5%. The relative standard deviation(RSD) was not more than 4.3% and standard addition recovery was 97%-103%.