共存金属离子对碳纤维中碱金属、碱土金属离子测定的干扰影响

本文采用火焰原子吸收光谱法,对碳纤维中碱金属,碱土金属离子的含量及试样中共存金属离子的干扰影响作了研究。由于碳纤维中钾、钠、钙、镁等离子在高温下易电离,会降低原子吸收的灵敏度(其中钙原子吸收灵敏度下降趋势尤为显著)。为了提高钙原子吸收的灵敏度,本文选用了氯化锶、氯化铯、氧化镧等抑制剂抑制待测金属离子的电离,提高钙原子吸收的灵敏度。抑制剂既能消除共存金属离子的干扰影响,又能提高分析结果的准确度。

DETERMINATION OF THE INTERFERING EFFECT OF COEXISTING METAL IONS ON DETERMINATION OF ALKALI METALAND ALKAEI-EARTH METAL IONS IN CARBON FIBRE

In the present paper flame atomic absorption spectrometry has been adopted to study the content of alkali metal and alkali-earth metal ions in carbon fibre as well as the concentration of coexisting metal ions in sample and their interfering effect. Due to the easy ionization of K, Na, Ca and Mg ions at high temperature, the sensitivity of atomic absorption will be reduced, particularly the Ca atom. In order to increase the sensitivity of absorption of Ca atom, we have selected SrCl2, CsCl2 and La2O3 as inhibitors to inhibit ionization of metal ions to be determined, the inhibitors can also eliminate the interfering effect of coexisting metal ions, improve the accuracy of the results.