In the petrochemical industry, methyl tert-butyl ether (MTBE) is one of the fastest developing petrochemical products in over 20 years. It is currently the most widely used component for adding high-octane unleaded gasoline and an intermediate product for separating high-purity isobutylene from mixed C4 fractions [1]. In industry, MTBE is synthesized in the liquid phase by isobutylene and methanol under the action of strong acidic cation resin catalyst under certain operating conditions. In the production process, the molar ratio of methanol to isobutylene (MRMI) of the reactor mixed feed is a crucial operating parameter [2]. The so-called MRMI, which refers to the ratio of the number of moles of methanol in the feed to the number of moles of isobutylene, must be controlled within a certain range according to process requirements. Its measurement efficiency and accuracy directly affect the operational control of MTBE production equipment. Traditional MRMI analysis often uses online chromatography methods, but due to their slow speed and high hardware maintenance requirements, the application effect is mostly unsatisfactory [3].