Title : Microwave-enhanced CO2 reforming with C2+ gas mixture
Abstract:
CO2 reforming is a promising technology that not only converts CO2 but also produces industrially valuable syngas within the framework of a carbon circular economy. However, current CO2 reforming primarily relies on CH4 as a reducing agent, leading to additional fossil fuel consumption and low economic feasibility. To address these issues, recent efforts have been made to utilize inexpensive and renewable reductants, such as biomass and waste plastics. Conventional indirect heating methods, such as electric furnaces or burners, pose challenges, including internal temperature non-uniformity, coke formation, and undesirable gas-phase side reactions in CO2 reforming. Catalytic direct heating enabled by electrification is essential for overcoming these limitations.
In this study, a CO2 reforming process was developed that employs pyrolysis gas from waste plastics as a reductant and utilizes microwaves as the heat source to address the aforementioned challenges. Ni-Mo-based catalysts were found to absorb microwaves more efficiently than SiC and exhibit stable CO2 conversion. Compared to electric furnaces, the microwave-assisted system demonstrated significantly improved conversion and stability, while also reducing coke deposition. Furthermore, in the electric furnace, pyrolysis gas decomposed thermally in the gas phase, causing coke to coat the reactor walls. In contrast, microwave heating effectively prevented this issue by selectively heating the catalyst. The CO2 reforming technology employing microwaves and waste plastic pyrolysis gas is expected to overcome the economic, durability, and fossil fuel dependency challenges of conventional CO2 reforming, thereby accelerating the commercialization of CO2 reforming processes.
