Ga supported on mesoporous HZSM-5 (GaOy/meso-HZSM-5) and conventional HZSM-5 (GaOy/micro-HZSM-5) catalysts were compared to investigate the effect of mesoporosity on the deactivation behavior in the coaromatization of methane and propane. The trend of reaction intermediate distribution between the catalysts became gradually different with time-on-stream, implying a distinction in deactivation behavior. These are attributed to the behavior of acid site blockage, because the production of BTX are driven by acid sites. The reaction with 13CH4 and further analyses revealed that the interaction between coke and Ga species that serve as Lewis acid sites is much stronger in GaOy/micro-HZSM-5 than in GaOy/meso-HZSM-5 post-reaction catalyst. Therefore, large amount of highly condensed coke was deposited in GaOy/micro-HZSM-5 during the reaction, leading to fast catalyst deactivation. Consequently, the structural difference arising from mesoporosity affects physicochemical properties of the catalysts thereby contributing to different deactivation behavior between the catalysts.
Bibliographical noteFunding Information:
This research was supported by C1 Gas Refinery Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT ( 2021M3D3A1A01022109 ). The Institute of Engineering Research at Seoul National University partially supported the research facilities for this work.
© 2021 Elsevier Ltd
- Acid site blockage
- Coaromatization of methane and propane
- Coke analysis
- Deactivation behavior
- Ga supported on HZSM-5
ASJC Scopus subject areas
- General Chemical Engineering
- Fuel Technology
- Energy Engineering and Power Technology
- Organic Chemistry