Oxidation and ammoxidation of propylene to acrolein and acrylonitrile with bismuth molybdates

Conference · Thu Sep 01 00:00:00 EDT 1983 · Am. Chem. Soc., Div. Pet. Chem., Prepr.; (United States)

OSTI ID:6805130

Goddard, W A; Allison, J N

Under appropriate conditions, bismuth molybdates can catalyze a number of transformations of olefins with selective oxidation being of particular importance. Experimental evidence suggests that the propylene is activated to an allylic species by a site associated with the Bi and that the oxidation step occurs at an Mo site. In order to address the mechanistic steps associated with these Mo sites. The authors discuss the chemistry of terminal oxo and imido groups. They find that for surface sites such as 1 about, 2 about and 3 about, the presence of two double bonds leads to a much more active species than those with a single multiple bond. This leads to a situation similar to that in olefin metathesis by high oxidation state Mo catalysis where the (spectator) oxo group species promotes formation of the metallacycle intermediate by formation of a partial Mo==O triple bond that stabilizes the intermediate. Calculations suggest that the magnitude of the spectator oxo activation is 35 kcal for species such as 1 about and 2 about and that the spectator imido stabilization is 15 kcal for species such as 1 about and 3 about. In addition, the calculations show some special coupling effects of the lone pairs of the Mo==NH groups that affect the geometries and possibly the mechanisms. The results of reactions of various organic substrates with species 1 about-5 about will be used to assess various steps in the mechanisms for 3) and 4), with the emphasis on 4). These results lead to support for the main features in the Barrington-Grasselli mechanism.

• Research Organization: Arthur Amos Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, California
• OSTI ID: 6805130
• Report Number(s): CONF-830814-
• Journal Information: Am. Chem. Soc., Div. Pet. Chem., Prepr.; (United States), Vol. 28:5; Conference: 186. national meeting of the American Chemical Society, Washington, DC, USA, 28 Aug 1983
• Country of Publication: United States
• Language: English

Related Subjects

10 SYNTHETIC FUELS
ACROLEIN
PRODUCTION
ACRYLONITRILE
ALKENES
AMMONOLYSIS
OXIDATION
PHASE TRANSFORMATIONS
BISMUTH OXIDES
CATALYTIC EFFECTS
MOLYBDENUM OXIDES
CHEMICAL REACTION KINETICS
SUBSTRATES
ALDEHYDES
BISMUTH COMPOUNDS
CHALCOGENIDES
CHEMICAL REACTIONS
DECOMPOSITION
HYDROCARBONS
KINETICS
MOLYBDENUM COMPOUNDS
NITRILES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
REACTION KINETICS
SOLVOLYSIS
TRANSITION ELEMENT COMPOUNDS
090121* - Hydrocarbon Fuels- Chemical Synthesis- (1976-1989)