Although the local geometry of Mo in Mo/HZSM-5 has been characterized before, we present a systematic way to manipulate the configuration of Mo and link it to its catalytic properties. The location and geometry of cationic Mo-complexes, the precursor of the active metal site for methane dehydroaromatization, are altered by directing the way they anchor to the framework of the zeolite. The feature used to direct the anchoring of Mo is the location of Al in the zeolite framework. According to DFT calculations, the local geometry of Mo should change, while UV-vis and pyridine FTIR spectroscopy indicated differences in the dispersion of Mo. Both aspects, however, did not influence the catalytic behavior of Mo/HZSM-5, indicating that as long as enough isolated Mo species are present inside the pores of the zeolite, the catalytic behavior is unaffected. This paves the way to better understand how the Mo oxo precursor transforms into the active phase under the reaction conditions.
Bibliographical noteFunding Information:
Financial support from the Sabic-NWO CATC1CHEM CHIPP project is gratefully acknowledged. Our thanks go to Dr. Christoph Dittrich (SABIC), Dr. Frank Mostert (SABIC) and Dr. T. Alexander Nijhuis (SABIC). G. Li acknowledges financial support from The Netherlands Organization for Scientific Research (NWO) for her personal VENI grant (no. 016. Veni.172.034) and NWO-Surf SARA for providing access to supercomputer resources.
© The Royal Society of Chemistry.
ASJC Scopus subject areas