近红外光谱法快速测定车用汽油中多种添加剂含量

为解决汽油中添加过量含氧化合物和未列入国家产品标准的添加剂化合物快速检测技术问题，提出了一种近红外光谱结合斜投影算法实现汽油中添加剂含量的快速分析方法。实验选用了四种不同种类的无氧汽油，包括调和汽油、FCC精制汽油、重整汽油和脱硫汽油，配制不同浓度、不同种类的添加剂化合物的系列汽油样品，使用傅里叶变换近红外光谱仪测定其近红外光谱，采用斜投影算法将被测添加化合物光谱信号从汽油光谱信号中分离出来，建立一元回归的标准工作曲线。预测分析中，根据分离的被测化合物光谱和标准工作曲线计算被测样本的添加化合物含量。此方法测定结果与真实含量之间绝对偏差小于0.8，相对偏差小于8%，用于实际汽油样本，此方法与气相色谱标准方法测定结果之间的绝对偏差小于0.85，相对偏差小于6.85%。本方法有效地解决了一般化学计量学多元校正方法建模维护工作量大，模型稳健性差的问题。对开发适合现场油品快速检测和有效加强我国汽油质量监管力度具有重要意义。

Rapid Quantitative Analysis of Content of the Additive in Gasoline for Motor Vehicles by Near-Inf rared Spectroscopy

A new rapid quantitative method for the determination of oxygenates and the compounds not included in the national standard in gasoline using near-infrared spectroscopy is raised by this paper. This method combine near-infrared spectroscopy with oblique projection. This experiment choose four different types of gasoline, including reconcile gasoline, FCC refined gasoline, reformed gasoline and desulfurizing gasoline. Prepare series gasoline samples containing different concentrations and different types of compounds. Using FTIR spectrometer to measure those samples and got transmission spectrums. Oblique projection method could separate quantity spectral signal from mixed spectrum signal, and using projection to calculate and analyze the separated signal to obtain the content of measured component. The deviation between this method and the real content is low, the absolute error is less than 0.8 and the relative error is less than 8%. For the actual gasoline samples, compare results of this method with gas chromatography, the absolute error are less than 0.85 and the relative error are less than 6.85%. This method solves the problem of general multivariate calibration methods. It is very significant for the development of rapid detection technology using NIR suitable for on-site and the improvement of the quality of gasoline.