The search for new adsorbents with enhanced capacity and selectivity, suitable for application on large-scale simulated moving-bed units for separation of p-xylene, requires efficient, reliable, and fast adsorbent characterization methods for this specific separation. Fixed-bed experiments were carried out under the conditions of the Parex process to evaluate a faujasite-type zeolite as adsorbent for the separation of p-xylene from its isomers in the proportions of the real Parex feed stream. The experimental breakthrough curves were used to evaluate the selected adsorbent in terms of nonselective and selective volumes, adsorption capacity, selectivity, and productivity, which can be applied to identify the feasible separation region for different operating conditions.