ICP光谱法测定铜精矿中砷含量的不确定度评定

Evaluation of Uncertainty in Determination of Arsenic in Copper Concentrate Using ICP Spectrophotometry

综合考虑称量过程、定容过程、测定过程引入的不确定度和重复性不确定度,对ICP光谱法测定的铜精矿中砷含量的不确定度进行评定。实现了评定结果的良好重复性,计算得到铜精矿中砷含量为0.355%,合成不确定度为0.014%。在95%的置信水平下,扩展不确定度为0.028%,不确定度评定结果表示为(0.355±0.028)%。还提出四点具体操作建议,供业界参考。

The uncertainty in determination of arsenic in copper concentrate determined by ICP spectrophotometry is evaluated by considering the uncertainty of weighing process, volumetric process and determination process, as well as the repeatability uncertainty. Good repeatability of determination result is realized： the arsenic content in the copper concentrate is 0.355% and the synthesis uncertainty is 0.014%. At 95% confidence level, the expanded uncertainty is 0.028%, and the result of uncertainty evaluation is （0.355±0.028）%. Moreover, four detailed operating suggestions are put forward for the reference of related fields.