Iron hydrous titanium oxide catalysts for the dehydrogenation of ethylbenzene to styrene
Hydrous titanium oxide (HTO) supports are amorphous, high surface area materials which can be loaded with highly dispersed catalytically active metals by ion exchange. Fe/HTO catalysts possess significant activity and selectivity for the dehydrogenation of ethylbenzene (EB) to styrene at 873 K. The most active Fe/HTO incorporates silicon into the HTO support to stabilize surface area. Conversions obtained with the best Fe/HTO catalysts studied to date are only 50-70% as great as those obtained with commercial bulk iron oxide catalysts. However, at least two potential improvements to the Fe/HTO catalysts have been identified which could increase activity significantly. First, previous work with HTO supports has shown that iron loadings can be at least doubled from the nominal 2 wt% iron loadings used in this study. Second, the Fe/HTO shrinks by 37% to 58% during reaction, decreasing the volume of the catalytic zone and thus reactant residence times compared to the residence time using bulk iron oxides. Several strategies are proposed for pre-shrinking the HTO`s to allow more active sites to be loaded into a given reactor volume. In addition to their potential superiority in bulk form, HTO`s can also be coated as thin films on a wide variety of substrates. Formation of such catalytically active films on membrane surfaces offers potential advantages in catalytic membrane reactor applications.
- Research Organization:
- Sandia National Labs., Albuquerque, NM (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC04-94AL85000
- OSTI ID:
- 10144198
- Report Number(s):
- SAND-93-2070C; CONF-940433-3; ON: DE94010381; TRN: 94:005068
- Resource Relation:
- Conference: Spring meeting of the American Institute of Chemical Engineers,Atlanta, GA (United States),17-21 Apr 1994; Other Information: PBD: Feb 1994
- Country of Publication:
- United States
- Language:
- English
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