Gasoline methanol content detection

Methanol content in gasolineHigh octane rating can to some extent increase the octane number, but with the increase of oxygen content, gasoline combustion efficiency is low, power is insufficient, and the oxidation stability of gasoline will be reduced. In addition, methanol has a strong corrosive effect on metals, plastics, and rubber, and also poses a significant threat to human health. China's gasoline product standards stipulate that methanol cannot be artificially added to gasoline.GB 17930-2016Regulations on Automotive Gasoline, Automotive Gasoline（Ⅳ、Ⅴ、ⅥA、ⅣB）ofmethanol content(Quality score) not greater than0.3%.

The methanol content in gasoline can be determined based onNB/SH/T0663The determination is carried out by gas chromatography, and the summary of the experimental method is as follows:1Use appropriate internal standards, such as1,2-Dimethoxyethane (ethylene glycol dimethyl ether)DME）Add it to the sample and then introduce it into a gas chromatograph equipped with two columns and a column switching valve. The sample is first subjected to polarityTCEPPre cut the column, first flush and empty the light hydrocarbons, while retaining the oxygen-containing compounds and heavier hydrocarbon components.2After methylcyclopentane, but in diisopropyl ether（DIPE）And methyl tert butyl ether（MTBE）Before flowing out of the pre cut column, switch the valve to the blowback position to allow the oxygen-containing compound to enter the non-polar stateWCOTAnalyze the column. Before any heavy hydrocarbon components flow out, allow alcohols and ethers to flow out of the analytical column in boiling order.3Benzene and methyl tert amyl ether（TAME）After flowing out of the analysis column, switch the column switching valve back to the starting position to blow back heavy hydrocarbon components.4Through flame ionization detector（FID）Or thermal conductivity detector（TCD）Detect the components flowing out, record the detector response value proportional to the component concentration, measure the peak area, and calculate the concentration of each component with reference to the internal standard.