Modelling product distribution of pyrolysis gasoline hydroprocessing on a Pt–Pd/HZSM-5 catalyst

The hydrocracking of pyrolysis gasoline (70 wt% of aromatics) has been studied using an integral fixed bed reactor with a Pt–Pd/HZSM-5 (0.2 wt% Pt, 0.48 wt% Pd; SiO2/Al2O3 = 19) catalyst over a wide range of experimental conditions: 350–450 °C; 20–50 bar; PPyGas = 1 bar, H2:PyGas molar ratio (nH2nH2), 20–49; WHSV, 2.7–32 h−1; Under these experimental conditions the deactivation is negligible and therefore data in the stationary state have been reported. Based on previous models for the hydrocracking of model compounds (methylcyclohexane and toluene), we have proposed a kinetic diagram and kinetic equations that satisfactorily describe the product distribution under the experimental conditions studied. The experimental data have been fitted to the proposed model and its parameters have been estimated. The kinetic model is used for reactor simulation and optimization.

► Pyrolysis gasoline with aromatic content higher than 70 wt% must be upgraded.
► Hydroprocessing PyGas yields alkanes for boosting olefin production in steamcrackers.
► Kinetic model able to predict product distribution in the hydroprocessing of PyGas.
► The kinetic model is based on the hydroprocessing of methylcyclohexane and toluene.