Selective propylene oxidation and ammoxidation mechanism of bismuth molybdate catalysts
Selective propylene oxidation and ammoxidation mechanism of bismuth molybdate catalysts was investigated by studying the reactions of labeled allyl alcohol (propylene oxidation intermediate) with fixed beds of Bi/sub 2/O/sub 3/, MoO/sub 3/, ..cap alpha..-Bi/sub 2/O/sub 3/-MoO/sub 3/, ..gamma..-Bi/sub 2/O/sub 3/-3MoO/sub 3/, and a Standard Oil Co. (Ohio) proprietary multicomponent bismuth molybdate catalyst in a pulse microreactor at 320/sup 0/C. MoO/sub 3/ showed up to 90Vertical Bar3< selectivity for acrolein at low allyl alcohol concentrations, but acrolein formation decreased in favor of benzene, diallyl ether, and particularly, 1,5-hexadiene at higher concentrations. With (..cap alpha..)- and (..gamma..)-bismuth molybdates, more propylene and no diallyl ether was formed. The use of pyridine as solvent instead of n-octane reduced diallyl ether yields to almost zero. Pure Bi/sub 2/O/sub 3/ was inactive. A reaction mechanism involving the initial formation of allyl molybdate o-complexes and acrolein formation by hydrogen abstraction from these complexes on Mo sites is suggested with isomerization leading to diallyl ether formation on both Mo and acidic sites. Bi sites enhance hydrogen abstraction by acting as electron sinks.
- Research Organization:
- Standard Oil Co., Ohio
- OSTI ID:
- 6821290
- Report Number(s):
- CONF-790917-
- Journal Information:
- Am. Chem. Soc., Div. Pet. Chem., Prepr.; (United States), Vol. 24:4; Conference: American Chemical Society national meeting, Washington, DC, USA, 10 Sep 1979
- Country of Publication:
- United States
- Language:
- English
Similar Records
Aspects of selective oxidation and ammoxidation mechanisms over bismuth molybdate catalysts. [Allyl iodide]
Formation of gas-phase. pi. -allyl radicals from propylene over bismuth oxide and. gamma. -bismuth molybdate catalysts
Related Subjects
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
BISMUTH
MOLYBDATES
PROPYLENE
OXIDATION
CATALYSTS
CHEMICAL REACTION KINETICS
CHEMICAL REACTION YIELD
ORGANIC SOLVENTS
REACTION INTERMEDIATES
TRACER TECHNIQUES
ALKENES
CHEMICAL REACTIONS
ELEMENTS
HYDROCARBONS
ISOTOPE APPLICATIONS
KINETICS
METALS
MOLYBDENUM COMPOUNDS
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
REACTION KINETICS
SOLVENTS
TRANSITION ELEMENT COMPOUNDS
YIELDS
400301* - Organic Chemistry- Chemical & Physicochemical Properties- (-1987)