In situ XAFS study for the formation mechanism of single iron site in the reaction of non-oxidative
Supported by NSFC(联合基金项目)
Principal Investigator: Dr. Xiaoguang Guo
Key Words: Non-oxidative conversion of methane; Single iron site; X – Ray Absorption Fine structure Spectra; Catalytic mechanism; In situ technology
Abstract:With the energy structure and strategy changing in China, natural gas has gradually become an important energy resource component. Thus the exploration of a more cost and resource effective route for the utilization of methane which is the main component of natural gas plays a vital role in the further development of energy industry in our country. Under such situation, the conversion of methane to high value-added chemicals, such as ethylene and aromatics has revived heated research interest around the world. This research program aims at conducting a more comprehensive study on the formation mechanism of the single iron active site during the pre activation of the non-oxidative methane to ethylene process with the aid of advanced in-situ X-ray absorption fine structure (EXAFS). More specifically, from in-situ EXAFS we can get the real time changes of the surface reconstruction, chemical environment, coordination structure and coordination number of the iron species, thus helping to gain more insight into the structure-activity relationship of the single iron based catalyst. Additionally, combined with DFT calculations, we can further reveal the formation mechanism of the single iron active site under reactive atmosphere and at the same time get the rate-determining step, which help for purposefully optimizing the catalyst and then reducing reaction temperature and improving the stability of the catalyst. In a word, this program will offer valid experimental evidence and theoretic guide for optimizing the catalyst for the non-oxidative methane to ethylene process and thus enrich the fundamental theory of this process and promote the development of nature gas industry.
Project Number: U1532117 (2016.1-2018.12)