Molecular simulation calculation has been performed to investigate the catalytic performance of metal-modified ((Fe, Co, Ni) SAPO-34 in methanol-to-olefins (MTO) process. Adsorption amount and adsorption heats of the reactant, methanol, and the main products, ethylene and propylene, in SAPO-34 and MeAPSO-34 (Me = Fe, Co, Ni) zeolites were analyzed and compared both in single adsorption and co-adsorption process with a Monte Carlo (MC) simulation method. On the other hand, with a molecular dynamics (MD) simulation method, the system energy of the molecules in three different positions was calculated and compared. The simulation results show that modifying SAPO-34 with Fe, Co, and Ni is beneficial to improve the selectivity of light olefins during the MTO process, especially for that of ethylene. And among the three MeAPSO-34 zeolites, the catalytic performance of NiAPSO-34 is the best.
Keywords: Light olefins; MTO; Molecular dynamics; Monte Carlo; SAPO-34.