In order to realize carbon neutrality of automotive engine, a new methanol engine concept and framework with the master cylinder and auxiliary cylinder working cooperated with each other is proposed, it integrates internal combustion Rankin cycle, charge transit between cylinders, store energy in gas and fuel reforming technologies. The literature research method is used to analyze the thermo-chemical reforming process of methanol in the activated atmosphere of exhaust gas. With internal Exhaust Gas Recirculation (EGR), the methanol is reformed to H₂, CO and CH₄ in the main cylinder to realize the mixture combusts in fusion of methanol and hydrogen. At the same time, the heat of exhaust gas, absorbed by the methanol, is converted into methanol combustion energy. The exhaust gas of the master cylinder is introduced into the auxiliary cylinder to continue combusting. The auxiliary cylinder not only continues the combusting of the master cylinder, but also acts as the post processor of the master cylinder combustion，and the combustion energy is recycled in multiple stages, so as to achieve efficient and clean combusting of the engine.

Methanol engine  /  Architecture  /  Carbon neutrality  /  Combustion thermal efficiency  /  Exhaust emission