文献类型：期刊文献

英文题名：Pathway of the cycle between the oxidative adsorption of SO₂ and the reductive decomposition of sulfate on the MgAl_2-xFe_xO₄ catalyst

作者：Wang, JA; Zhu, ZL; Li, CL

机构：[1]Univ Nacl Autonoma Mexico, Inst Phys, Mexico City 01000, DF, Mexico;[2]E China Univ Sci & Technol, Petr Proc Res Ctr, Shanghai 200237, Peoples R China

年份：1999

卷号：139

期号：1

起止页码：31

外文期刊名：JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000078068400004)】；

语种：英文

外文关键词：sulfur-transfer catalyst; Mg-Fe-Al-O; De-SO2; pollution control; mechanism

摘要：The behaviors of the SO2 oxidative adsorption and the reduction decomposition of formed sulfate over Mg-Fe-Al-O mixed spinel catalyst were studied by in situ IR, MR-GC-MS, Mossbauer spectroscopy and electrical conductivity measurement techniques. In the oxidative adsorption and/or reaction process, SO2 and oxygen molecules are adsorbed on the lattice oxygen ions and oxygen vacancies, respectively. During the SO2 adsorption and reaction, adsorbed sulfur species react with the lattice oxygen ions and form the sulfite-like species. When oxygen molecules are present in the feed mixture, sulfate is formed from the sulfite-like species reacting with the adsorbed oxygen ions. When the sulfated samples are reduced by hydrogen at 773 K, a large amount of H2S along with a small part of SO2 is produced. Different iron species, Fe3+, Fe2.5+, Fe2+ and Fe-0 are identified in the sulfated sample during the reduction process. In the half cycle of SO2 oxidative adsorption and reaction, iron ions are directly involved in the formation of the mixed sulfate; in the half cycle of the reduction, due to the S-O-Fe bond being easily broken, the reducibility of the mixed sulfate hence is improved. A mechanism on the cycle between SO2 oxidative adsorption and sulfate reductive decomposition is proposed. (C) 1999 Elsevier Science B.V. All rights reserved.