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

Abstract

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 ACCu‑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 °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: N2-BET (N2 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 SO4 2– could be formed in the reaction process and then strongly adsorbed. SO2, CS2, and COS were detected in the effluent gas generated from ACCu‑CoSPc‑Ce‑CS2 with TPD. Therefore, we conclude that ACCu‑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 ACCu‑CoSPc‑Ce can be regenerated by thermal desorption with less capacity loss at least twice.

High-Performance Arsine Removal Using CuOx/TiO2 Sorbents under Low-Temperature Conditions

“…Figure shows the CO 2 -TPD profiles of the samples with pH = 5, pH = 7, and pH = 10. The peak area corresponds to the amounts of basic sites, while the desorption temperature represents the strength of basic sites of the sorbents. , It could be seen that the CO 2 -TPD spectra of samples exhibited three desorption peaks in the temperature range of 175.5–216.5 °C (weak basic sites), 409.7–464.1 °C (moderate-to-strong basic sites), and 634.0–680.6 °C (strong basic sites). According to the CO 2 -TPD test results, the desorption peak area of the sample with pH = 7 was not obvious, indicating that the basic sites were quite few in number in the sample.…”