18O2 label mechanism of sulfur generation and characterization in properties over mesoporous Sm-based sorbents for hot coal gas desulfurization

Abstract Using a sol–gel method, Sm Me O x /MCM-41 or SBA-15 ( Me  = Fe, Co and Zn) and corresponding unsupported sorbents were prepared. The desulfurization performance of these sorbents was evaluated over a fixed-bed reactor and the effects of reaction temperature, feed and sorbent composition on desulfurization performance were studied. Samarium-based sorbents used to remove H 2 S from hot coal gas were reported for the first time. The results of successive sulfidation/regeneration cycles revealed that SmFeO 3 /SBA-15 sorbent was suitable for desulfurization of hot coal gas in the chemical industry. The formation of elemental sulfur during both sulfidation and regeneration processes depended strongly on the catalytic action of Sm 2 O 2 S species, which was confirmed for the first time via high sensitive time of flight mass spectrometer (TOF-MS) using 6%vol 18 O 2 /Ar regeneration gas and can reduce markedly procedural complexity. The sorbents were characterized using N 2 -adsorption, high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), temperature-programmed reduction of H 2 (H 2 -TPR), thermogravimetry (TG) and time-of-flight mass spectrometry (TOF-MS) techniques.