Terahertz time-domain spectroscopy-based method for detection of content of methanol in methanol gasoline

The present invention provides a terahertz time-domain spectroscopy-based method for detection of content of methanol in methanol gasoline, and relates to the technical field of oil composition detection. The method is as follows: obtaining multiple methanol-concentration-known methanol gasoline samples with as standard samples; using terahertz time-domain spectroscopy to detect the standard samples and a to-be-tested sample, according to the terahertz parameter spectrum and methanol concentrations of the standard samples, using partial least squares method and cross-validation method to confirm the optimal principal component; setting the terahertz parameter spectrum and methanol concentrations of the standard samples and the optimal principal component as partial least squares regression method parameters for modeling calculation to obtain partial least squares regression coefficients and a partial least squares regression model; according to the partial least squares regression coefficients, the terahertz parameter spectrum of the to-be-tested sample, and the partial least squares regression model, obtaining the content of methanol in the to-be-tested sample. The terahertz time-domain spectroscopy-based method can achieve the purpose of detection of content of methanol in methanol gasoline by the terahertz time-domain spectroscopy.