Efficient use of waste carton for power generation, tar and fertilizer through direct carbon solid oxide fuel cell

The rapid development of express logistics industry has yielded more carton wastes, how to utilize them as resources has become an important issue in recent years. In this paper, effective and multifunctional applications of waste carton are explored to obtain products of solid carbon fuel and tar via pyrolysis process. Solid carbon derived from waste carton is utilized as fuel for direct carbon solid oxide fuel cells (DC-SOFCs) with the symmetric perovskite La0.3Sr0.7Fe0.7Ti0.3O3-δ electrodes and scandium stabilized zirconia electrolyte for power generation. The maximum output performance of this DC-SOFC is up to 307.8 mW cm-2 at 850 °C. The cell fueled by 0.2 g carbonated waste carton is operated at constant resistance discharging mode of 20 Ω, and 5.8 h discharging with a capacity of 658 C is represented. Ash of the carton fuel is collected after operation. Infrared spectrum and surface-enhanced Raman spectrum are employed to characterize tar from pyrolysis, and they show that tar contains many organic matters with a potential to be used as chemical raw materials. Energy dispersive spectroscopy and X-ray diffraction results show various inorganic salts and oxides in the ash, it means that the ash may be a promising candidate for fertilizer. [Display omitted] •Efficient use of waste carton is explored on energy saving.•DC-SOFC fueled by carbonated waste carton exhibits maximum power density of 307.8 mW cm−2.•Tar from carton pyrolysis has many organic compounds with various using values.•Ash after cell discharging has multiple inorganic salts and oxides.