碱熔-电感耦合等离子体原子发射光谱法测定铝用炭素材料中15种元素

铝用炭素材料无法采用普通酸溶解,需要经过灰化-熔融-酸浸取法或混合酸-微波消解法处理。实验选择灰化-偏硼酸锂熔融法处理样品,即:700 ℃下灰化6 h、1 000 ℃下偏硼酸锂熔融5 min、10%(V/V)硝酸浸取熔块,避免了高温处理样品引起某些测定元素的损失;同时对由熔剂引入产生的基体效应采用基体匹配法进行消除;选择Al 396.152 nm、Ba 455.403 nm、Ca 317.933 nm、Cr 267.716 nm、Fe 259.940 nm、K 766.490 nm、Mg 285.213 nm、Mn 257.610 nm、Na 589.592 nm、Ni 231.604 nm、P 177.495 nm、Si 288.158 nm、Ti 334.941 nm、V 292.402 nm和Zn 213.856 nm为分析线,在绘制校准曲线时进行基体匹配,实现了电感耦合等离子体原子发射光谱法(ICP-AES)对铝用炭素材料中15种元素的测定。方法中各元素校准曲线的线性相关系数均大于0.999;各元素的检出限为0.000 01%～0.000 3%,定量限为0.000 04%~0.001 0%。方法用于测定铝用炭素标准样品GPW-4、GPW-5、GPW-6中各元素,测定结果的相对标准偏差(RSD, n=6)为0.17%～10%;回收率为91%～107%;测定结果与标准值基本一致。

Determination of fifteen elements in carbon material for aluminum by inductively coupled plasma atomic emission spectrometry with alkali fusion

Carbon material for aluminum can not be completely dissolved with common acids, and should be treated by ashing-fusion-acid leaching or mixed acid-microwave digestion. In experiments, the sample was treated by ashing-lithium metaborate fusion method. The sample was ashed at 700 ℃ for 6 h followed by fusion with lithium metaborate at 1 000 ℃ for 5 min. Then the melt was leached with 10% (V/V) nitric acid, avoiding the loss of some testing elements due to the high temperature treatment. Meanwhile, the matrix effect caused by the introduction of flux was eliminated by matrix matching method. Al 396.152 nm, Ba 455.403 nm, Ca 317.933 nm, Cr 267.716 nm, Fe 259.940 nm, K 766.490 nm, Mg 285.213 nm, Mn 257.610 nm, Na 589.592 nm, Ni 231.604 nm, P 177.495 nm, Si 288.158 nm, Ti 334.941 nm, V 292.402 mmand Zn 213.856 nm were selected as the analytical lines. The matrix matching was conducted during the preparation of calibration curve. Accordingly, the determination of 15 elements in carbon material for aluminum by inductively coupled plasma atomic emission spectrometry (ICP-AES) was realized. The linear correlation coefficients of calibration curves for testing elements were all higher than 0.999. The limits of detection were between 0.000 01% and 0.000 3%, and the limits of quantification were between 0.000 04%-0.001 0%. The proposed method was applied for the determination of certified reference material of carbon material for aluminum(GPW-4, GPW-5,GPW-6). The relative standard deviations (RSD, n=6) were between 0.17% and 10%. The recoveries were between 91% and 107%. The found results were basically consistent with the standard values.