Zn-modified ZSM-5 zeolites with different zinc contents were successfully prepared by the impregnation method and compared with unmodified ZSM-5. Their potential for LPG (liquefied petroleum gas) aromatization and the conversion of pyrolysis gases obtained from recycled polypropylene was subsequently evaluated. In this process, various characterization tests were performed on the prepared catalysts, including SEM-EDS (scanning electron microscopy with energy-dispersive spectroscopy), TPD-NH₃ (temperature-programmed desorption of ammonia), and FTIR (Fourier-transform infrared spectroscopy). Under optimized conditions, the best results were obtained with 2% Zn/ZSM-5, which generated a higher production of BTX (benzene, toluene, and xylene) isomers, which are major components of gasoline. Likewise, in catalytic pyrolysis of recycled polypropylene, this catalyst generated a higher production of aromatic compounds. Therefore, this catalyst showed excellent performance in generating valuable hydrocarbons of great industrial interest, particularly aromatics.