Analysis of Methanol Content in Methanol Gasoline Based on Calibration of Portable Raman Spectrometer

As an alternative fuel to gasoline, methanol gasoline is economical and environmentally friendly, and its methanol concentration has a significant effect on calorific value, explosion resistance, and combustion efficiency. As a nondestructive, rapid, portable, easy-to-operate, and low-cost analytical method, portable Raman spectroscopy has been applied to the analysis of the methanol content of methanol gasoline. However, the nonlinear Raman frequency-shift demonstration error of portable Raman spectrometers affects the accuracy of analytical modeling. A method for methanol content analysis of methanol gasoline with portable Raman spectrometer calibration is proposed. The polystyrene Raman frequency-shifted reference material is used for multi-point calibration, and a peak detection algorithm is used for the calibration of Raman spectra. Based on two characteristic peaks of methanol, a binary linear regression method is proposed to establish a quantitative analysis model. The prediction results and evaluation indexes of the model show that this method can predict the methanol content more accurately.