Article,
Catalytic partial oxidation of higher hydrocarbons: reactivities and selectivities of mixtures
Chemical Engineering Science, 59 (22-23): 5501-5507 (2004)
Abstract
Model hydrocarbon mixtures (n-octane + i-octane, n-decane + n-hexadecane,
n-decane + naphthalene) were reacted with air over a rhodium-coated
monolith in an effort to determine relative reactivities of various
homologues in gasoline and diesel fuels. This information is required
to determine the appropriate operating conditions for achieving maximum
syngas yields from these fuels. We find that the overall reactivity
of these fuel mixtures is not simply an average over the reactivities
of constituent molecules. Results indicate that, whereas i-octane
is more reactive than n-octane in the mixture at all C/O feed ratios,
n-decane is more reactive than n-hexadecane in the mixture only at
ratios leaner than the syngas stoichiometry (based on the mixture)
and this trend reverses as the C/O feed ratio increases. Addition
of 10 mol% naphthalene to n-decane successfully produces syngas in
selectivities exceeding 70%. This demonstrates the ability of the
rhodium-monolith reactor to partially oxidize a wide variety of hydrocarbon
mixtures, including the hydrogen-deficient poly-aromatic compounds,
to syngas and olefins without any evident deterioration in performance.
