论文部分内容阅读
钡天青石矿物中主要含钡、锶、硫酸根以及镁、钙、钠和其他少量元素,这些元素中钡、锶、钠等对微量钾的测定有较大的电离干扰。由于钾的电离电位仅4.34电子伏特,在乙炔～空气火焰中电离大约50％,不仅使吸光度下降,而且标准曲线弯曲。为了提高测定灵敏度和消除因钡锶钠等元素的电离引起的干扰,研究了用锶盐为电离缓冲剂,乙二胺四乙酸为保护剂,镧盐为抑制剂,消除其干扰。本文拟定了用氟氢酸和高氯酸分解试样后,直接用原子吸收分光光度法测定钡天青石中的微量钾。 实验部分
Barium Celestite minerals contain mainly barium, strontium, sulfate and magnesium, calcium, sodium and other small elements, these elements barium, strontium, sodium and other determination of trace amounts of potassium have a greater ionization interference. As the potassium ionization potential is only 4.34 eV, ionization in the acetylene ~ air flame is about 50%, not only decreasing the absorbance but also curving the standard curve. In order to improve the sensitivity and eliminate the interference caused by the ionization of barium, strontium and other elements, strontium salt as ionizing buffer, ethylenediaminetetraacetic acid as protective agent and lanthanum salt as inhibitor were studied to eliminate the interference. In this paper, after the sample was decomposed with hydrofluoric acid and perchloric acid, the trace potassium in barium lanthanum was directly determined by atomic absorption spectrophotometry. Experimental part