ROLE OF FUNCTIONAL GROUPS ON ADSORPTION AND MICROWAVE REGENERATION OF ACTIVATED CARBON FIBER CLOTH

摘要

Activated Carbon Fiber Cloth (ACFC) is typically regenerated using resistive heating or steam. There is limited information about the regeneration of ACFC using microwave heating, possibly due to the lack of information about its dielectric properties. This research characterizes the impact of functional groups on the adsorption and regeneration properties of virgin, oxidized, and hydrogen (H_2)-treated ACFC. Four grades of ACFC were treated with a concentrated acid mixture or with H_2 at 950℃. Nitrogen (N_2) and water vapor (H_2O) adsorption isotherms were obtained to determine the surface areas, distribution of pore sizes and volumes, and adsorption capacities of the virgin and chemically modified ACFCs. X-ray Photoelectron Spectroscopy (XPS) was completed to determine the elemental composition of the samples. The regeneration properties of the resulting ACFC samples were evaluated based on the measurement of their microwave attenuation constants and resistivity. The acid-treated samples contained more oxygen and demonstrated less microwave attenuation and higher resistivity than the virgin samples. In contrast, the H_2-treated samples contained less oxygen and demonstrated more microwave attenuation and lower resistivity than the virgin samples. The influence of the chemical treatment on the structure and adsorption of H_2O and N_2 is also discussed based on the material characterization tests.