气相色谱法测定邻苯二甲酸酐纯度的测量不确定度评定

Evaluation of Uncertainty in Measurement of Purity of Phthalic Anhydride by Gas Chromatography

按照GB/T 15336-2013《邻苯二甲酸酐》,用气相色谱法测定邻苯二甲酸酐的纯度并建立数学模型,对测定过程中影响检测结果的各不确定度来源进行分析和评定。通过计算重复性、样品质量、溶剂体积、响应因子等因素带来的不确定度,得到邻苯二甲酸酐纯度测量结果的合成不确定度。实验结果表明,不确定度的主要影响因素为溶剂体积,其次为响应因子和样品质量。通过对不确定度进行评估,有利于提高检测结果的可靠性,可以为准确测定邻苯二甲酸酐的纯度提供理论依据。

According to GB/T 15336-2013“phthalic anhydride”,the purity of phthalic anhydride was determined by gas chromatography,and the mathematical model was established.The sources of uncertainty in the determination process were analyzed and evaluated.The synthetic uncertainty of purity measurement results of phthalic anhydride was obtained by calculating the uncertainty caused by repeatability,sample mass,solvent volume and response factor.The experimental results showed that the main factors affecting the uncertainty was solvent volume,followed by response factor and sample quality.Through the evaluation of uncertainty,it was helpful to improve the reliability of the test results and can provide theoretical basis for the accurate determination of phthalic anhydride purity.