Did MTBE escape China's refined oil consumption tax, and what does that mean for margins?

Did MTBE escape China's refined oil consumption tax, and what does that mean for margins?
China's 2023 announcement clarifying the scope of refined oil consumption tax added alkylate, petroleum ether, white oil, heavy aromatics and mixed aromatics to the taxable list, but MTBE was not included. That omission matters because roughly 95% of Chinese MTBE still flows into gasoline blending, and the country's MTBE capacity already exceeds 13 million tons per year. With tax treatment left unchanged, theoretical margins reportedly climbed toward 26% by mid-2023. The structural problem remains: MTBE economics have long been weak because etherification-grade C4 is mostly self-produced and internally settled, so published margins understate real profitability while overstating how attractive the merchant market looks.