Abstract
Dozens of Cu zeolites with MOR, FAU, BEA, FER, CHA and MFI frameworks are tested for direct oxidation of CH4 to CH3OH using H2O2 as oxidant. To investigate the active structures of the Cu zeolites, 15 structural variables, which describe the features of the zeolite framework and reflect the composition, the surface area and the local structure of the Cu zeolite active site, are collected from the Database of Zeolite Structures of the International Zeolite Association (IZA). Also analytical studies based on inductively coupled plasma-optical emission spectrometry (ICP-OES), X-ray fluorescence (XRF), N2 adsorption specific surface area measurement and X-ray absorption fine structure (XAFS) spectral measurement are performed. The relationships between catalytic activity and the structural variables are subsequently revealed by data science techniques, specifically, classification using unsupervised and supervised machine learning and data visualization using pairwise correlation. Based on the unveiled relationships and a detailed analysis of the XAFS spectra, the local structures of the Cu zeolites with high activity are proposed.
Highlights
Dozens of Cu zeolites with MOR, FAU, BEA, FER, CHA and MFI frameworks are tested for direct oxidation of CH4 to CH3OH using H2O2 as oxidant
C H3OH, CH3OOH, or HCOOH are observed as the products, and the main product is varied with the catalysts
According to the literature, CH3OH is formed by the decomposition of CH3OOH, while HCOOH is formed by overoxidation of C H3OH or non-selective oxidation[24]
Summary
Dozens of Cu zeolites with MOR, FAU, BEA, FER, CHA and MFI frameworks are tested for direct oxidation of CH4 to CH3OH using H2O2 as oxidant. The active site structures of methane monooxygenase (MMO) have been studied intensively because they offer direct oxidation of CH4 to C H3OH even at ambient temperature and pressure. When Cu zeolites are applied to CH4 oxidation using H 2O2 in batch type reactors, C H3OH and CH3OOH are selectively produced while overoxidation to HCOOH and C O2 are suppressed[16,23,24]. The problem of this process is the high cost of H 2O2 which is more expensive than C H3OH, Scientific Reports | (2021) 11:2067. Methods for direct oxidation of C H4 to C H3OH need to be improved further for practical application
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
