Catalytic reduction of sulfur dioxide*1

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.

Section: ■ Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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

Yang

Peng

Zhao

et al. 2021

“…Paik et al have reported the selective reduction of SO 2 by H 2 and obtained good results, , but the high reaction temperature and the problems of H 2 prices, sources, and transportation are still limiting factors. Moody et al successfully studied Ru-supported catalysts for the reduction of SO 2 , but the cost of catalyst was high. Kim et al successfully developed Co 3 O 4 –TiO 2 catalysts for the reduction of SO 2 by CO to elemental sulfur.…”

Section: Introductionmentioning

confidence: 99%

Selective Reduction of SO₂ in Smelter Off-Gas with Coal Gas to Sulfur over Metal Sulfide Supported Catalysts

Zuo

Zhang

et al. 2018

A series of metal sulfide supported catalysts were first developed for the SO2 reduction to sulfur by coal gas, and different supports and active components were selected to prepare catalysts through the wet impregnation method. This reduction technology is also a promising desulfurization process of smelter off-gas. Before the calcined supported catalyst was evaluated in a fixed-bed reactor, the presulfidation was performed to get the stronger stability and catalyst ability. The catalysts were characterized by X-ray diffraction, XPS, BET, and SEM analyses. Changes in the catalyst structure and active phase were explored. The acid–base properties of the supports were detected by CO2-TPD, and the reduction ability of the catalyst was evaluated via CO-TPR. The long life of catalyst was evaluated, and the probable catalytic mechanism was proposed.

“…When H 2 is the reductant, the operating cost will be high. Using low-cost coal as the reductant leads to low quality of the sulfur product . Dry reduction of SO 2 by CO will produce poisonous byproduct (COS).…”

Section: Introductionmentioning

confidence: 99%

“…Using low-cost coal as the reductant leads to low quality of the sulfur product. 13 Dry reduction of SO 2 by CO will produce poisonous byproduct (COS). More importantly, these dry reduction processes require high reaction temperature (>430 K) to obtain complete conversion of SO 2 .…”

Section: Introductionmentioning

confidence: 99%

Selenium-Assisted Reduction of Sulfur Dioxide by Carbon Monoxide in the Liquid Phase

Yang

Chai

Zhu

et al. 2017

Regenerable flue gas desulfurization (FGD) is highly attractive because of the transformation of sulfur dioxide (SO2) to high-value products. In this study, selenium-assisted SO2 reduction by carbon monoxide (CO) in the liquid phase [dimethylformamide (DMF) + water (H2O) mixture] is proposed and applied in the FGD process. This process realizes recycle of the elemental sulfur product under room temperature. Moreover, results show that both the selenium catalyst and DMF solvent have good stability and can be well recycled, implying that this process is economically feasible. Furthermore, the mechanism of selenium-assisted SO2 reduction by CO in DMF/H2O is investigated. Results show that the selenium catalyst dissolves in solution and forms Se n 2– species, which are the active intermediates and promote formation of the sulfur product.