Supported manganese dioxide catalyst for seawater flue gas desulfurization application

详细信息	查看全文 | 推荐本文 |

• 作者：Junjie Bian ; ^{junjiebian@ouc.edu.cn} ; Shu Zhang ; Jingwei Zhang ; Xin Min ; Chunhu Li
• 关键词：Manganese dioxide ; Catalytic oxidation ; Preparation ; Seawater ; Flue gas desulfurization
• 刊名：Chemical Engineering Journal
• 出版年：2012
• 期刊代码：16_13858947
• 类别：ce
• 出版时间：1 May, 2012
• 卷：189-190
• 期：Complete
• 页码：57-61
• 文件大小：450 K

摘要

In seawater flue gas desulfurization (FGD) process, ceramic supported MnO_x catalysts were developed to improve SO₂ removal efficiency of the scrubber by increasing S(IV) oxidation rate at the low pH values. These supported MnO_x catalysts were prepared by impregnation-precipitation method, calcined at different temperatures, and exposed to simulated flue gases to investigate the catalytic oxidation of sulfur dioxide in seawater buffering system. Compared with 鈥渂lank鈥?ceramic, the most active MnO_x/ceramic catalyst, 623MnO_x/ceramic, that was prepared by doping (NH₄)₂CO₃ as the precipitant and calcined at 623 K, exhibited up to 17%higher SO₂ conversion at the GHSV 3000 h^鈭? in the industrial feasible temperature range of 318-358 K. XPS spectra revealed manganese was in the state of oxidation +4 on the surface of 623MnO_x/ceramic. XRD patterns and SEM-EDS spectra indicated that the high activity of 623MnO_x/ceramic for S(IV) oxidation at low temperatures could be attributed to oxygen activation and transfer ability of highly dispersed MnO₂ on ceramic support. H₂-TPR profiles showed the low temperature reduction peak was shifted to higher temperature when the calcination temperature increased from 573 K to 723 K, and low temperature reducible manganese species were related to catalytic activity for S (IV) oxidation. The good performance of MnO₂/ceramic catalyst on the SO₂ removal appeared to be promising in seawater FGD application when high sulfur coals were burned.