Production of Linear Octenes from Oligomerization of 1-Butene over Carbon-Supported Cobalt Catalysts
- Univ. of Wisconsin, Madison, WI (United States)
- The Dow Chemical Company, Freeport, TX (United States)
Here, linear octenes were produced in high (70–85%) selectivity from oligomerization of liquid 1-butene using carbon-supported cobalt oxide catalysts in a continuous flow reactor. The liquid products were characterized by two-dimensional gas chromatography–mass spectrometry. Above 95% of the oligomers were C8 olefins, with the other products primarily being branched C12 olefins. The linear octene products at a conversion of 9.77% decreased in selectivity according to 3-octene > trans-2-octene > cis-2-octene > 4-octene. Methyl-heptenes including trans/cis-5-methyl-2-heptene > trans/cis-5-methyl-3-heptene > trans-3-methyl-2-heptene (at the lowest conversion) were the other major products summing to 15.6%. The selectivity of linear octenes decreased from 84 to 78% as the conversion increased from 10% to 29%. The product distribution suggests the reaction pathway involves a head-to-head coupling of two 1-butene molecules to form internal linear octenes. Head-to-tail coupling of two 1-butene molecules or a coupling between 1-butene and 2-butene forms the observed methyl-heptenes. The rate of head-to-head coupling is higher than the rate of head-to-tail or the rate of 1-butene to 2-butene coupling as indicated by the higher selectivity of linear octenes. The activated catalyst contained both Co3O4 and CoO as confirmed by X-ray diffraction (XRD), in situ Raman spectroscopy, and X-ray absorption spectroscopy. The cobalt oxide particle size was estimated to be between 5 and 10 nm by high-resolution transmission electron microscopy and XRD. The Co3O4/CoO ratio decreased with increasing pretreatment temperature. Metallic cobalt, which has a low catalytic activity, formed at 550 °C.
- Research Organization:
- Argonne National Laboratory (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
- Sponsoring Organization:
- The Dow Chemical Company
- OSTI ID:
- 1257483
- Journal Information:
- ACS Catalysis, Journal Name: ACS Catalysis Journal Issue: 6 Vol. 6; ISSN 2155-5435
- Publisher:
- American Chemical Society (ACS)Copyright Statement
- Country of Publication:
- United States
- Language:
- ENGLISH
Similar Records
Epoxidation of lower olefins with hydrogen peroxide and titanium silicalite