Dealuminated H-Y zeolites: Influence of the number and type of acid sites on the catalytic activity for isopropanol dehydration
Φόρτωση...
Ημερομηνία
Συγγραφείς
Triantafyllidis, K. S.
Evmiridis, N. P.
Τίτλος Εφημερίδας
Περιοδικό ISSN
Τίτλος τόμου
Εκδότης
Περίληψη
Τύπος
Είδος δημοσίευσης σε συνέδριο
Είδος περιοδικού
peer reviewed
Είδος εκπαιδευτικού υλικού
Όνομα συνεδρίου
Όνομα περιοδικού
Industrial & Engineering Chemistry Research
Όνομα βιβλίου
Σειρά βιβλίου
Έκδοση βιβλίου
Συμπληρωματικός/δευτερεύων τίτλος
Περιγραφή
The effect of the number and type of acid sites of H-Y catalysts dealuminated by different techniques on the dehydration of 2-propanol has been studied in this work. The increase in the number of acid sites generally increases the activity for the formation of both main products, propene and diisopropyl ether. The presence of different types of extraframework phases generated by steaming or treatment by SiCl(4) or by (NH(4))(2)SiF(6) treatment affects the activity and selectivity in different ways. The yield of propene is always higher than that of ether but shows a minimum at 95 degrees C in the catalysts with few acid sites and Si-Al amorphous phases formed by dealumination with SiCl(4). Highly crystalline catalysts with relatively high acidity (parent or dealuminated by (NH(4))(2)SiF(6) or steaming/EDTA) give propene yields higher than ether's only at temperatures higher than 95 degrees C. The presence of extraframework Al generated by relatively low-temperature steaming reduces the catalyst activity for both products. A statistical analysis of the turnover frequency at different temperatures showed that all acid sites of the crystalline zeolitic phase participate in the formation of both products, while the catalytic sites of the amorphous phase formed by SiCl(4) contribute at relatively low temperatures with propene as the main product. A common compensation effect for the formation of both products exists for all the tested crystalline dealuminated H-Y catalysts.
Περιγραφή
Λέξεις-κλειδιά
silicon tetrachloride, hydrothermal treatment, aluminum, alcohol, decomposition, faujasites, al
Θεματική κατηγορία
Παραπομπή
Σύνδεσμος
<Go to ISI>://000089211200017
http://pubs.acs.org/doi/pdfplus/10.1021/ie000002s
http://pubs.acs.org/doi/pdfplus/10.1021/ie000002s
Γλώσσα
en
Εκδίδον τμήμα/τομέας
Όνομα επιβλέποντος
Εξεταστική επιτροπή
Γενική Περιγραφή / Σχόλια
Ίδρυμα και Σχολή/Τμήμα του υποβάλλοντος
Πανεπιστήμιο Ιωαννίνων. Σχολή Θετικών Επιστημών. Τμήμα Χημείας