Studies on the state of dispersion of mo(vi) supported on γ-a1203 doped with alkali cations

dc.contributor.author	Κονδύλης, Χρίστος Η.	el
dc.contributor.author	Βολιώτης, Σταύρος	el
dc.contributor.author	Λυκουργιώτης, Αλέξιος Σ.	el
dc.contributor.author	Βάττης, Δημήτριος Κ.	el
dc.contributor.author	Delmoń, Bernard	en
dc.date.accessioned	2015-05-27T08:26:03Z
dc.date.available	2015-05-27T08:26:03Z
dc.date.issued	2015-05-27
dc.identifier.uri	http://hdl.handle.net/11400/11223
dc.rights	Αναφορά Δημιουργού-Μη Εμπορική Χρήση-Όχι Παράγωγα Έργα 3.0 Ηνωμένες Πολιτείες	*
dc.rights.uri	http://creativecommons.org/licenses/by-nc-nd/3.0/us/	*
dc.source	http://www.sciencedirect.com/science/article/pii/S0166983400818771#	el
dc.subject	Catalysis
dc.subject	Alkali cations
dc.subject	Αλκαλικά κατιόντα
dc.subject	Dispersion
dc.subject	Διασκόρπιση
dc.subject	Κατάλυση
dc.title	Studies on the state of dispersion of mo(vi) supported on γ-a1203 doped with alkali cations	en
heal.type	journalArticle
heal.classification	Chemical technology
heal.classification	Biochemistry
heal.classification	Χημική τεχνολογία
heal.classification	Βιοχημεία
heal.classificationURI	http://skos.um.es/unescothes/C00565
heal.classificationURI	http://skos.um.es/unescothes/C00386
heal.classificationURI	N/A-Χημική τεχνολογία
heal.classificationURI	N/A-Βιοχημεία
heal.keywordURI	http://id.loc.gov/authorities/subjects/sh85020938
heal.identifier.secondary	ISSN: 01669834
heal.identifier.secondary	DOI: 10.1016/S0166-9834(00)81877-1
heal.language	en
heal.access	campus
heal.recordProvider	Τεχνολογικό Εκπαιδευτικό Ίδρυμα Αθήνας. Σχολή Τεχνολογίας Τροφίμων & Διατροφής. Τμήμα Τεχνολογίας Τροφίμων	el
heal.publicationDate	1984
heal.bibliographicCitation	Kordulis, C. H., Voliotis, S., Lycourghiotis, A. S., Vattis, D. K. and Delmoń, B. (1984). Studies on the state of dispersion of mo(vi) supported on γ-a1203 doped with alkali cations. "Applied Catalysis ", 11(2), 1984. pp 179-193. Available from: http://www.sciencedirect.com/science/article/pii/S0166983400818771#. [Accessed 02/08/2001]	en
heal.abstract	Doped supports were fabricated by dry impregnation of γ-A1203 with various amounts of MNO3 (M+: Li+, Na+, K+, Rb+ and Cs+). A quantity of molybdenum(vi) corresponding to 12 % wt MoO3 was deposited on each modified support. The influence of the content of the modifier on the specific surface area of γ-A1203 was examined. A diminution in the specific surface area due to the toping has been observed. The magnitude of this effect generally increases with the modifier content. A model taking into account the above observation has been postulated. The dispersion of the alkali cations on the γ-A1203 surface as well as the dispersion of Mo(vi) on the doped supports were studied using X-ray photoelectron spectroscopy:the dispersion of the alkali cations remains constant within the region 0.392-1.55 mmol of modifier per g of γ-A1203 followed by a considerable decrease at higher concentrations. As to Mo(vi),the variation in the dispersion with the dopant concentration depends on the kind of alkali cation. Thus, Li+ doping causes no considerable effect on the Mo(vi) dispersion. In contrast to that, doping by Na+, K+, Rb+ and Cs+ provokes a linear decrease in the Mo(vi) dispersion up to 1.55 mmol of the modifier per g of γ-A1203. Further increase in the dopant concentration has a quite weak effect on the dispersion. Diffuse reflectance spectroscopy measurements showed that the ratio of the K-M-S functions determined at 305 and65nm,F(R∞)305F(R∞)265,depends on the kind and content of the modifier: Li+ has no effect. The ratio mentioned decreases linearly with the Na+ (in the whole range of concentrations) and K+,Cs+and Rb+)up to 1.55 mmol per g of γ-A1203. A model postulated to explain the above mentioned X-ray photoelectron spectroscopy and Diffuse reflectance spectroscopy results, suggests the formation of surface alkali molybdates at the expense of the supported polymeric Mo (vi).	en
heal.journalName	Applied Catalysis	en
heal.journalType	peer-reviewed
heal.fullTextAvailability	true