Highly porous activated carbon synthesized by pyrolysis of polyester fabric wastes with different iron salts: Pore development and adsorption behavior

Different inorganic iron salts were selected as activating agents to investigate the effects of chloridion (Cl−) and iron in different valence states (Fe3+ and Fe2+) on pore and structure development of polyester fabric wastes-based activated carbons. Physicochemical properties of activated carbons were conducted by EA, N2 adsorption/desorption isotherms, XRD, SEM, XPS and FTIR. And the pyrolysis characteristics of the samples were detected by TG analysis. The results showed that carbons activated by FeCl3 and FeCl2 had well-developed porosity with BET surface areas around 1400 m2/g, almost 3.7 times larger than that by FeSO4, which was attributed to the formation of CCl bond, facilitating to motivate the cross-linking reaction. The diversity in microporosity was found between carbons activated by FeCl3 and FeCl2 on account of the different roles of Fe3+ and Fe2+ and the distinct pyrolysis pathway. Furthermore, carbon activated by FeCl2 presented excellent adsorption performance toward eriochrome black T with the maximum adsorption capacity of 450.23 mg g−1.