离子交换色谱-火焰发射光谱法测定高纯钨粉中痕量钾和钠

Determination of Potassium and Sodium in High Purity Tungsten Powder by Ion-Exchange Chromatography-Flame Atomic Emission Spectrometry

方法用阳离子交换色谱分离钨基体，同时富集痕量杂质元素钾、钠，以火焰发射光谱法测定5N高纯钨粉中痕量钾钠。钨基体99．98％以上有效分离，钾钠的富集倍数达1～2个数量级。本方法有效地降低试验空白，以提高分析灵敏度，钾、钠检测下限分别为0．10，0．50μg·g^-1，可以满足高纯钨粉（5N）和仲钨酸铵（5N）的分析要求。采用火焰发射光谱法检测钾、钠，具有较高的稳定性和灵敏度，标准加入回收率在89％～115％，对于痕量钾、钠分析是一种较理想的分析方法。

Ion-exchange chromatography was applied to separate tungsten matrix and the trace elements potassium, sodium were enriched, and then were determined by flame atomic emission spectrometry. Enrichment factor found is 100 times. This method decreases the test blank observably, so it improves the sensitivity, and it can be used in analyzing high purity tungsten and ammonium paratungstate. Flame atomic emission spectrometry provides good stability and sensitivity, the RSD is potassium 4.2%, sodium 15.4 %, the recovery is between 89 % - 115 %. So it is an ideal method for testing trace potassium and sodium in tungsten.