Ce-Modified Mo/γ-Al₂O₃ Catalysts for Production of Elemental Sulfur through Reducing SO₂

Abstract

A series of metal-modified Mo/γ-Al 2 O 3 catalysts were fabricated using the impregnation method. The influence of Ce content on the catalytic performance was systematically studied in a fixed-bed reactor. The catalysts were characterized by X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscopy, and the Brunauer−Emmett−Teller technique. The reduction ability of the catalysts was recorded via H 2 temperature-programmed reduction. The valence state of Mo was raised to 6+ by the addition of Ce. What is more, the effect of temperature and GHSV were considered, and the evaluation of the optimized catalyst life catalyst was tested. A sulfur yield of 88.27% was achieved at 350 °C with SO 2 /H 2 = 1:3.

Self-Assembly Preparation of Al2O3/MoS2 Bifunctional Catalyst for Highly Efficient Reduction of SO2 to Elemental Sulfur

“…The XPS spectra of Mo in Al 2 O 3 /MoS 2 catalysts with different amounts of PVP addition are shown in Figure . According to previous research reported, the ratio of Mo 6+ /Mo 4+ in a fresh catalyst played an important role in the catalytic performance of a Mo-based Al 2 O 3 catalyst. The catalytic activity was enhanced with the increase of the ratio of Mo 6+ /Mo 4+ .…”

“…The detail descriptions of reactor, catalyst analysis, catalyst filling quantity, and calculation formulas of SO 2 conversion, sulfur selectivity, and yield of sulfur were referred to previous work. 40 The compositions of products and raw materials were analyzed by a gas chromatograph (GC 9890B) equipped with a thermal conductivity detector (TCD) and an autosampler. The contents of SO 2 and H 2 S were determined by external standard methods.…”

“…The catalytic performances of Al 2 O 3 /MoS 2 catalysts were evaluated by using a fixed-bed reactor. The detail descriptions of reactor, catalyst analysis, catalyst filling quantity, and calculation formulas of SO 2 conversion, sulfur selectivity, and yield of sulfur were referred to previous work . The compositions of products and raw materials were analyzed by a gas chromatograph (GC 9890B) equipped with a thermal conductivity detector (TCD) and an autosampler.…”

Capture and Catalytic Reduction of SO2 with H2 to Elemental Sulfur by Novel Guanidinium-Based Deep Eutectic Solvents

“…Catalytic reduction of SO 2 to the high-value-added element sulfur is considered to be a promising alternative to recover sulfur resource from flue gas. In catalytic SO 2 reduction, H 2 , − CO, − H 2 S, − CH 4 , , and a mixture of them such as coal gas are commonly used as reducing agents, especially the use of clean energy H 2 as a reducing agent, in which only sulfur and water are reduced products. Equilibrium calculations suggest that a lower temperature is beneficial to the conversion of SO 2 and the yield of elemental sulfur.…”

Insights into the Molecular Structure of MoOx Catalysts via Static and Transient Raman Experimentation

“…In recent decades, there has been growing interest in the use of supported molybdenum catalysts owing to their outstanding performance in various processes. − Multiple attempts have been made to enhance the reactivity of active molybdenum sites ,,− through modification of their physicochemical properties either by using promoters or a mixed-oxide support phase. However, the simultaneous presence of multiple species with potentially different reactivities may lead to ambiguous interpretations about the link between the synthesis and performance of oxide catalysts.…”