In this project, we used hydrothermal method instead of traditional pyrolysis to transform rigid PU waste into N-doped activated carbon for capacitor and adsorption. We have investigated several factors to increase the adsorption capacity and to decrease the cost of chemicals and electrical power. Our experimental results indicated that the obtained activated carbon has 6% of nitrogen element and > 1000 m2/g of specific surface area with 20%-30% production yield. In the isothermal sorption experiment, the adsorption capacity was 769 mg/g significant larger than that of commercial activated carbon. Regarding with the electrochemical analysis, its capacitance outperformed evaluated by cyclic voltammetry. Compared to the commercial activated carbon for supercapacitor, our N-doped activated carbon showed superior SAC、MDR、energy input、ENAS and in a single-pass CDI reactor. The payback period is lower than 2 years. This work not only reduces solid waste but also generates new resource.

Hydrothermal carbonization, Polyurethane wastes, Activated carbon