The reactor is one of the most important equipment to be designed for optimal process operations. An appropriate reactor modeling leads to an efficient and optimal process conceptual design, simulation, and eventually construction. The key for success in this step is mainly related to kinetics. The present work is centered toward process simulation and aims at comparing three different kinetic models for methanol synthesis. The comparison shows how the refitted Graaf model, presented in a previous study, effectively predicts the performance of modern methanol synthesis loops. To pursue this objective, we simulated in Aspen HYSYS three methanol synthesis technologies (the most popular technologies in modern plants) and compared the results with industrial data. The proposed case study demonstrates that the refitted Graaf model is more accurate in output prediction than the wellestablished original Graaf and Vanden Bussche−Froment models, which are currently considered the industrial benchmark, thus showing how the refitted Graaf model is a potential candidate for future industrial applications.