Knowledge Management System Of Guangzhou Institute of Energy Conversion, CAS
| Alkali Metal-Promoted LaxSr2-xFeO4-delta Redox Catalysts for Chemical Looping Oxidative Dehydrogenation of Ethane | |
Gao, Yunfei1; Haeri, Farrah1; He, Fang2 ; Li, Fanxing1
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| 2018-03-01 | |
| Source Publication | ACS CATALYSIS
 |
| ISSN | 2155-5435 |
| Volume | 8Issue:3Pages:1757-1766 |
| Corresponding Author | Li, Fanxing(fli5@ncsu.edu) |
| Abstract | Chemical looping oxidative dehydrogenation (CL-ODH) represents a redox approach to convert ethane into ethylene under an autothermal scheme. Instead of using gaseous oxygen, CL-ODH utilizes lattice oxygen in transition metal oxides, which acts as an oxygen carrier or redox catalyst, to facilitate the ODH reaction. The oxygen-deprived redox catalyst is subsequently regenerated with air and releases heat. The current study investigated alkali metal (Li, Na, and/or K)-promoted LaxSr2-x,FeO4-delta (LaSrFe) as redox catalysts for CL-ODH of ethane. While unpromoted LaSrFe exhibited poor ethylene selectivity, addition of Na or K promoter achieved up to 61% ethane conversion and 68% ethylene selectivity at 700 degrees C. The promotional effect of K on LaSrFe was characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), low-energy ion scattering spectroscopy (LEIS), transmission electron microscopy (TEM), O-2-temperature-programmed desorption (TPD), H-2-temperature-programmed reduction (TPR), and O-18(2) surface exchange. XPS and XRD showed that K incorporates into the mixed-oxide structure at low loading levels (e.g., 0.1K-LaSrFe), whereas the surface of LaSrFe was enriched with K cation at high loading levels. LEIS indicates that the outermost surface layer was covered by potassium oxide. This surface layer was characterized to be amorphous under TEM. It was further determined that the surface layer increased the resistance for O2- diffusion from the bulk and its subsequent evolution into electrophilic oxygen species on the surface. As such, nonselective oxidation of ethane is inhibited. The synergistic effect of copromoting LaSrFe with Li and K was also investigated. Li and K copromotion improved the redox catalyst performance to 86% ethylene selectivity and 60% ethane conversion while maintaining an oxygen capacity of ca. 0.65 wt %, making it a promising candidate for CL-ODH. |
| Keyword | oxidative dehydrogenation chemical looping redox catalyst core-shell perovskite alkali promotion |
| DOI | 10.1021/acscatal.7b03928 |
| WOS Keyword | METHANE PARTIAL OXIDATION ; CHLORIDE CATALYSTS ; OXIDE CATALYSTS ; LIGHT ALKANES ; OXYGEN ; POTASSIUM ; ETHYLENE ; PROPANE ; SCHEME ; KINETICS |
| Indexed By | SCI |
| Language | 英语 |
| Funding Project | U.S. National Science Foundation[CBET-1604605] ; Kenan Institute for Engineering, Technology, and Science at NC State University ; State of North Carolina ; National Science Foundation |
| WOS Research Area | Chemistry |
| Funding Organization | U.S. National Science Foundation ; Kenan Institute for Engineering, Technology, and Science at NC State University ; State of North Carolina ; National Science Foundation |
| WOS Subject | Chemistry, Physical |
| WOS ID | WOS:000426804100018 |
| Publisher | AMER CHEMICAL SOC |
| Citation statistics | |
| Document Type | 期刊论文 |
| Identifier | http://ir.giec.ac.cn/handle/344007/23285 |
| Collection | 中国科学院广州能源研究所 |
| Corresponding Author | Li, Fanxing |
| Affiliation | 1.North Carolina State Univ, Dept Chem & Biomol Engn, 911 Partners Way, Raleigh, NC 27695 USA 2.Chinese Acad Sci, Guangzhou Inst Energy Convers, Guangzhou 510640, Guangdong, Peoples R China |
| Recommended Citation GB/T 7714 | Gao, Yunfei,Haeri, Farrah,He, Fang,et al. Alkali Metal-Promoted LaxSr2-xFeO4-delta Redox Catalysts for Chemical Looping Oxidative Dehydrogenation of Ethane[J]. ACS CATALYSIS,2018,8(3):1757-1766. |
| APA | Gao, Yunfei,Haeri, Farrah,He, Fang,&Li, Fanxing.(2018).Alkali Metal-Promoted LaxSr2-xFeO4-delta Redox Catalysts for Chemical Looping Oxidative Dehydrogenation of Ethane.ACS CATALYSIS,8(3),1757-1766. |
| MLA | Gao, Yunfei,et al."Alkali Metal-Promoted LaxSr2-xFeO4-delta Redox Catalysts for Chemical Looping Oxidative Dehydrogenation of Ethane".ACS CATALYSIS 8.3(2018):1757-1766. |
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