In chemical reactions, a principal and influential parameter is particle size. The effect of HZSM-5 catalyst particle size on the kinetics of methanol conversion to gasoline has been investigated in this work. Three catalysts of 90 nm (Z1), 1 m (Z2) and 4 m (Z3) containing Si/Al ratios of 25, and a 90 nm sized with a Si/Al ratio of 50 (Z4) were prepared. The experiments were performed at temperatures of 598, 623 and 648 K at different feed rates. Chen and Schipper kinetic models, credible models for MTG process, were chosen to study the catalyst particle size effect on MTG process kinetics. R2 adj. values for each of the models show that the experimental data are in relatively good agreement with Chen and Schipper models. In order to check the results of modeling with experimental data, objective function parameter was applied as a criterion and Z1 catalyst showed the best performance using
Chen model, closely followed by Z2.