The modifications of 2 oxides with Sb/Fe ratios of 1 and 2 during calcination at <1000° and after catalytic tests (1-butene oxidn. to butadiene) were studied by x-ray diffraction, IR, and Moessbauer analyses. A nonstoichiometric (NS) rutile structure with excess Sb held within the structure itself is formed on both catalysts calcined at ≤900°. The strong increase both in selectivity and activity in allylic oxidn. shown by the catalyst with an Sb/Fe ratio of 2 is attributed to the formation of a NS-rutile that is stable during catalytic tests. The excess Sb held within the structure creates Sb:O double bonds which are responsible for the increase of selectivity and activity. The fundamental role of the method of prepn. by copptn. in a basic medium is also suggested. [on SciFinder(R)]
Titolo: | The role of excess antimony as a promoter of activity and selectivity in selective oxidation in the iron-antimony system |
Autori: | |
Data di pubblicazione: | 1985 |
Rivista: | |
Abstract: | The modifications of 2 oxides with Sb/Fe ratios of 1 and 2 during calcination at <1000° and after catalytic tests (1-butene oxidn. to butadiene) were studied by x-ray diffraction, IR, and Moessbauer analyses. A nonstoichiometric (NS) rutile structure with excess Sb held within the structure itself is formed on both catalysts calcined at ≤900°. The strong increase both in selectivity and activity in allylic oxidn. shown by the catalyst with an Sb/Fe ratio of 2 is attributed to the formation of a NS-rutile that is stable during catalytic tests. The excess Sb held within the structure creates Sb:O double bonds which are responsible for the increase of selectivity and activity. The fundamental role of the method of prepn. by copptn. in a basic medium is also suggested. [on SciFinder(R)] |
Handle: | http://hdl.handle.net/11570/1907386 |
Appare nelle tipologie: | 14.a.1 Articolo su rivista |