التفاصيل البيبلوغرافية
| العنوان: |
Kinetic Evaluation of Deactivation Pathways in Methanol-to-Hydrocarbon Catalysis on HZSM‑5 with Formaldehyde, Olefinic, Dieneic, and Aromatic Co-Feeds |
| المؤلفون: |
Brandon L. Foley (6939752), Blake A. Johnson (6939755), Aditya Bhan (1392250) |
| سنة النشر: |
2021 |
| المجموعة: |
Smithsonian Institution: Digital Repository |
| مصطلحات موضوعية: |
Biochemistry, Medicine, Genetics, Molecular Biology, Neuroscience, Evolutionary Biology, Mental Health, Infectious Diseases, Computational Biology, Environmental Sciences not elsewhere classified, Chemical Sciences not elsewhere classified, 673 K decreases, HCHO-mediated deactivation pathways, 0.2 kPa HCHO, HZSM, MTH catalysis, diene, Aromatic Co-Feeds Formaldehyde, 12 kPa CH 3 OH, co-feeding 1 kPa propylene, cause deactivation, HCHO co-feed pressure, site-loss selectivity |
| الوصف: |
Formaldehyde (HCHO), formed in situ by transfer dehydrogenation of methanol in methanol-to-hydrocarbon (MTH) conversion, reacts with other organic species including olefins, dienes, and aromatics to cause deactivation. The propensity of these formaldehyde-mediated pathways to cause deactivation during MTH catalysis is evaluated using site-loss selectivity and yield as numerical assessors of catalyst deactivation. The site-loss selectivity of HCHO with 0.2 kPa HCHO and 12 kPa CH 3 OH at 673 K decreases by 80% when co-feeding 1 kPa propylene, increases by 2× when co-feeding toluene, and increases by 150× when co-feeding 1,3-butadiene, suggesting that olefins react with HCHO in nondeactivating pathways, while aromatics and dienes react with HCHO in pathways that lead to deactivation. Further, dienes have a much higher propensity than aromatics to cause deactivation via HCHO-mediated reactions when compared on a molar basis, suggesting that dienes may be critical intermediates in HCHO-mediated deactivation pathways. This is corroborated by evidence that the site-loss selectivity of HCHO increases with increasing HCHO co-feed pressure, implying that prevalent deactivation pathways are higher order in HCHO than predominant competing nondeactivation pathways. Plausibly this occurs because HCHO reacts with itself or with a HCHO-derived species en route to deactivation, such as a diene or an aromatic, which are known products of HCHO-mediated pathways during MTH catalysis. Therefore, dienes along with HCHO should be considered as critical intermediates in fomenting deactivation in MTH catalysis and strategies to eliminate polyunsaturated species and/or intercept reaction sequences of these intermediates with HCHO will likely enhance catalyst lifetime during MTH catalysis. |
| نوع الوثيقة: |
article in journal/newspaper |
| اللغة: |
unknown |
| Relation: |
https://figshare.com/articles/journal_contribution/Kinetic_Evaluation_of_Deactivation_Pathways_in_Methanol-to-Hydrocarbon_Catalysis_on_HZSM_5_with_Formaldehyde_Olefinic_Dieneic_and_Aromatic_Co-Feeds/14179504 |
| DOI: |
10.1021/acscatal.0c05335.s001 |
| الاتاحة: |
https://doi.org/10.1021/acscatal.0c05335.s001 |
| Rights: |
CC BY-NC 4.0 |
| رقم الانضمام: |
edsbas.5D8DE098 |
| قاعدة البيانات: |
BASE |