Synthesis of CoMo catalysts supported on EMT/FAU intergrowth zeolites with different morphologies and their hydro-upgrading performances for FCC gasoline

摘要

The EMT, EMT/FAU intergrowths and FAU zeolites were synthesized and applied as the additives of the catalysts for FCC gasoline hydro-upgrading. The physico-chemical properties of the as-synthesized catalysts were characterized by various techniques including XRD, N-2 adsorption-desorption, HRTEM, SEM, etc. The results revealed that the zeolite-incorporated catalysts exhibited high specific surface areas, pore volumes and suitable acidities. Among the supported CoMo catalysts containing pure EMT zeolite with different particle sizes, the micrometer-sized EMT-incorporated catalyst CoMo/AE-3 showed the highest HDS efficiency (96.1%), but with the greatest loss of octane number (23 unit) due to its excessive olefin saturation. Moreover, compared with the supported CoMo catalysts containing micrometer-sized EMT and EMT/FAU intergrowth zeolites, the EMT/FAU-incorporated catalyst CoMo/AE-5 (CoMo/EMT/FAU-2-gamma-Al2O3) with excellent pore structure and suitable amounts of B and L acidity sites exhibited a good balance in HDS efficiency (94.6%) and RON preservation (0.5 unit). This could be ascribed to the synergy of zeolite EMT and zeolite FAU that balanced the functions among the HDS, aromatization and isomerization. (C) 2015 Elsevier B.V. All rights reserved.