Facile synthesis of tailored mesopore-enriched hierarchical porous carbon from food waste for rapid removal of aromatic VOCs

Due to the large amount, environmental impact, and complex properties of accumulated food waste, its disposal and valorization has become a growing global concern and challenges. In this study, a series of mesopore-enriched hierarchical porous carbons were synthesized from a mixture of two food waste components (peptone and bone). The prepared materials were employed for the rapid adsorption of aromatic volatile organic compounds (VOCs). The pore structures, morphology and surface chemistry of the food waste-based microporous activated carbon (PCs) and mesopore-enriched hierarchical porous carbons (PC/BCs) were characterized and then compared. PC/BCs presented larger pore volume (2.45 cm3/g vs. 1.25 cm3/g) than the PCs because of their activation and the template effect of the bone, allowing them to exhibit satisfactory adsorption capacities (139.5 mg/g for benzene and 440.7 mg/g for toluene) and adsorption rate (0.285 min−1 for benzene and 0.236 min−1 for toluene) for aromatic VOCs. In addition, a strong linear relationship (R2 = 0.957) was also established between the adsorption rate k and total pore volume, highlighting the role of mesopores in PC/BCs, which contributed 60% to the total pore volume, during the rapid capture of VOCs. Further, PC/BCs also showed excellent thermal regeneration performance for more than four runs. The results of this study provide a feasible approach to fabricating mesopore-enriched hierarchical porous carbon from food waste, which could enable the rapid removal of VOCs.