Recently, Associate Professor Wu Long from the Low-Carbon and Green Process Equipment Team of the School of Mechanical Engineering, Tianjin University of Science and Technology, together with a team from Tsinghua University, has made new progress in research on the high-value utilization of plastics. This research achievement was published inChemical Engineering Journal—a Class A TOP journal in the field of engineering technology—under the title "Biochar-enhanced induced heating promotes efficient hydrogen production from plastic".

The study proposes a new strategy for plastic pyrolysis-reforming hydrogen production based on the synergistic effect of induction heating and biochar coupling. It significantly improves hydrogen yield and greatly reduces process energy consumption, providing a new technical approach for the high-value utilization of plastic recycling and clean hydrogen energy production. The first author and corresponding author of the paper is Teacher Wu Long from the School of Mechanical Engineering of our university, with Tianjin University of Science and Technology as the first completing unit. Associate Professor Zhou Hui from Tsinghua University is the co-corresponding author.

With the continuous growth of global plastic production, traditional disposal methods of waste plastics (such as landfilling and incineration) bring severe environmental problems and carbon emission pressures. Although pyrolysis gasification technology can convert plastics into high-value gaseous fuels, it still faces challenges such as high energy consumption, easy deactivation of catalysts, and low hydrogen production efficiency.

Based on this, the paper innovatively combines induction heating technology with biochar, and realizes efficient reforming hydrogen production from plastics under the action of a high-frequency alternating electromagnetic field. Research shows that under the condition of the new technology, the hydrogen production performance of plastic pyrolysis reforming can reach up to 3978.8 mL/g, an increase of 40.7% compared with traditional methods, while the process energy consumption is reduced by 36%. The technology shows good applicability to a variety of typical plastics (HDPE, LDPE, PP, PS, PET), with the maximum increase in hydrogen production reaching 88.7%.

Studies have shown that induction heating not only achieves rapid and uniform heating, but also induces electron enrichment on the biochar surface through the electromagnetic field. This enhances interface charge transfer, promotes C-H bond cleavage and steam reforming reactions, and significantly improves the kinetics of hydrogen generation. In addition, the structure of biochar undergoes self-optimization during the reaction, and its pore structure and graphitization degree are maintained, which further enhances its reaction activity and stability.

This research work will provide new ideas for the high-value conversion of plastics and contribute to the goals of "carbon neutrality and carbon peaking". The research was supported by the Youth Project of the National Natural Science Foundation of China.