The applicability of a monolith system to a retrofit application for the hydrogenation of pyrolysis gasoline (Pygas) is evaluated. A direct comparison between a trickle bed (extruded trilobe) and a washcoated monolith is made using a simulated model Pygas mixture. Comparable nickel impregnated onto alumina catalysts (trilobe and monolith) are evaluated in a laboratory recycle reactor operating under the same industrially relevant conditions of temperature, pressure, and liquid/gas flow rate. The inferred flow rates are an order of magnitude lower than those used in many monolith studies. The volumetric rate of reaction over the monolith is approximately twice that of the trickle bed. The trickle bed, operated in both the trickle-flow and transition regimes, is mass-transfer-limited. Monoliths appear to give a rate benefit by virtue of mass-transfer enhancement. The rate of hydrogenation at two different flow velocities gave almost identical results for all components. However, these rate enhancements may not be as significant as previously claimed when considering operation at equivalent superficial velocities. No significant changes in selectivity are observed between the trickle bed and monolith operation.