Adsorption of Carbon Disulfide on Cu/CoSPc/Ce Modified Activated Carbon under Microtherm and Micro-oxygen Conditions

Removal efficiency of CS2 (carbon disulfide) by activated carbon modified with different impregnants has been studied under micro-oxygen conditions. It was found that adsorbent AC(Cu-CoSPc-Ce) Possesses markedly enhanced adsorption purification ability. Reaction temperature and oxygen concentration were found to be crucial factors for the adsorption purification processes, and 60 degrees C as well as 2.0% oxygen seem to be the optimal conditions for CS2 removal. The structure of activated carbon samples and reaction mechanism were closely examined by a number of characterization techniques as follows: N-2-BET (N-2 adsorption/desorption), XRD (X-ray powder diffraction), XPS (X-ray photoelectron spectroscopy), SEM-EDS (scanning electron microscopy-electron diffraction spectroscopy), and CO2-TPD (temperature-programmed desorption of CO2). Presumably, large quantities of SO42- could be formed in the reaction process and then strongly adsorbed. SO2, CS2, and COS were detected in the effluent gas generated from AC(Cu-CoSPc-Ce-CS2) with TPD. Therefore, we conclude that AC(Cu-CoSPc-Ce) most likely functions as a catalyst in the adsorption/oxidation process on the surface of the impregnated sample. Sulfides and sulfur oxides generated can cover the active sites of adsorbents, resulting in pronounced reduction of adsorbent activity. The exhausted AC(Cu-CoSPc-Ce) can be regenerated by thermal desorption with less capacity loss at least twice.