Temperature programmed desorption of carbon dioxide on activated carbon supported bimetallic oxides of Ni-Fe

The activated carbon (AC) supported bimetallic oxides of Ag-Fe/AC and Ni-Fe/AC were synthesized by the wet impregnation method. The adsorbents were explored to study their chemisorption and physisorption properties in CO2 capture. The physisorption and chemisorption were measured by using a gas sorption analyzer via CO2 adsorption isotherm at 25 °C and temperature programmed desorption of carbon dioxide (TPD-CO2) analyses, respectively. The Ni-Fe/Ac was found to be most efficient through the chemisorption and physisorption screening. The X-ray diffraction showed a typical pattern for amorphous peaks for graphitic structure with the presence of the peaks that are associated with NiO and Fe2O3. The adsorption quantities for physisorption and chemisorption were obtained at 88.63 and 36.10 mg/g, respectively. For TPD-CO2 analysis, the significant peaks for Ni/AC and Fe/AC at the desorption temperature range of 349-504 and 487-764 °C, respectively, vanished for Ni-Fe/AC. The Ni-Fe/AC exhibited a chemical shift in the desorption temperature range at 450-539 °C might correspond to the interaction of the Ni-Fe that should be further investigated.