This study evaluates the performance of three adsorbents, ETS-4, MSC 3K 172, and Norit RB3, for a 68/32 %vol CH4/N2 separation in biogas upgrading, using a two-stage Pressure Swing Adsorption (PSA) system modeled in Aspen Adsorption. Sensitivity analysis indicated that adsorption pressure, desorption pressure and adsorption time significantly influence methane recovery and product purity. Among the materials tested, ETS-4 demonstrated the highest N2 selectivity and most favorable breakthrough behavior, followed by MSC 3K 172 and Norit RB3. Under optimized conditions, ETS-4 achieved up to 85% CH4 recovery at 81% purity. These results provide a robust benchmark for the development of high-efficiency PSA-based upgrading systems.