(560g) Hydrogenation of 2-Methylnaphthalene over Bi-Functional Supported Nickel Catalysts

The products of thermal biomass conversion processes, such as pyrolysis, tend to be mixtures of aromatic and poly-aromatic compounds. While aromatics are desirable for gasoline (boiling point cuts below 200°C), they are not desirable in middle distillates. Instead, middle distillate fractions need to be hydrogenated and have naphthenic rings opened to improve the combustion characteristics for kerosene and diesel applications. Thermal DeOxygenation (TDO) is a thermal conversion process that converts organic acids in cellulose hydrolyzates to an essentially oxygen-free organic oil containing a large number of substituted naphthalene compounds.

The current study identifies catalysts and upgrading strategies for the TDO oil using 2-methylnaphthalene as a model compound. Although there have been many studies performed on monocyclic compounds, there have been fewer studies focused on the hydrogenation of naphthalene derivatives. We have focused on nickel as a catalyst because of its low cost and high tolerance to potential impurities in the oil. Furthermore, we have demonstrated that naphthols, which are the predominant oxygen species in TDO oil, are easily deoxygenated over high-surface-area nickel. However, this catalyst is not effective for opening rings. Therefore, a fixed-bed reactor operating in differential mode was used to test nickel supported on oxides with varying acidity to determine the activity and selectivity of the bi-functional catalysts for hydrogenation and ring opening.