Dynamic hydrogenation studies in a catalytic slurry reactor

Hydrogenation of α‐methyl styrene with Pd/Al 2 O 3 catalyst was studied in a three‐phase stirred slurry reactor. Responses to step inputs of H 2 in N 2 carrier gas provided temporal moments that allowed estimation of separate values for reversible adsorption and irreversible surface reaction rates for reactant H 2 . Mass transfer resistances are either estimated from other sources and shown to be small, or are evaluated from the flow rate dependence of the moments. The adsorption equilibrium constant for H 2 on the catalyst was measured with reaction product cumene as the solvent. For temperatures between 290 and 322 K adsorption appears to have the dominant influence on the overall rate of hydrogenation. The energy of activation for the adsorption step was found to be 8 kcal/mol.