ICP-AES测定废水中铝的不确定度评定

Uncertainty Evaluation of ICP-AES Determination of Aluminum in Wastewater

在生态环境检测领域,测量不确定度评定越来越具有广泛性和实用性,是行业发展的需求。实验室质量管理和质量保证中也对不确定度评定工作极为重视。本次实验的测定目标是采用电感耦合等离子体发射光谱仪测定水样中铝的质量浓度,遵循的环保行业标准是《水质32种元素的测定电感耦合等离子体发射光谱法》(HJ 776-2015)。通过对标准溶液、标准工作曲线拟合、前处理消解过程等影响测定结果的不确定度分量进行分析,计算出测定结果的扩展不确定度,并找出影响该不确定度的主要因素。由此可知,电感耦合等离子体原子发射光谱法(ICP-AES)测定废水中铝含量的不确定度的主要来源是标准曲线非线性引入的不确定度。本次实验所测废水中铝浓度的不确定度报告为(0.99±0.063)mg/L。

In the field of ecological environment detection,the evaluation of measurement uncertainty is becoming increasingly widespread and practical,which meets the demand for industry development.Uncertainty assessment is also highly valued in laboratory quality management and quality assurance.The objective of this experiment was to determine the mass concentration of aluminum in water samples.An inductively coupled plasma emission spectrometer was used,following the environmental industry standard Determination of 32 Elements in Water Quality by Inductively Coupled Plasma Emission Spectroscopy(HJ 776-2015).By analyzing the uncertainty components that affect the measurement results,such as standard solution,standard working curve fitting,and pre-treatment digestion process,the extended uncertainty of the measurement results was calculated,and the main factors affecting this uncertainty were identified.It can be inferred that the main source of uncertainty in the determination of aluminum content in wastewater by inductively coupled plasma atomic emission spectrometry(ICP-AES) was the uncertainty introduced by the nonlinearity of the standard curve.The uncertainty report of aluminum concentration in the wastewater measured in this experiment was(0.99±0.063) mg/L.