Catalysis Today, Vol.274, 109-115, 2016
The delaminating and pillaring of MCM-22 for Fischer-Tropsch synthesis over cobalt
To investigate the effect of structural evolution of layered zeolite on the performance of Co/MCM-22 derived zeolites for Fischer-Tropsch (FT) synthesis, the MCM-22, MCM-36 and delaminated zeolite characterized by different arrangement of MWW nanosheets were prepared through directly calcination, pillaring and delaminating of the layered precursor of the MCM-22 (MCM-22(P)). The results show that the extent of reduction of cobalt was increased over Co-supported pillared and delaminated zeolites, and the activities of the catalysts (i.e., CO conversions) were increased in the order of Co/MCM-22 < Co/Al2O3-MCM-36 < Co/SiO2-MCM-36 < Co/delaminated zeolite. Compared to Co/MCM-22, the selectivity of CH4 over Co-supported pillared and delaminated zeolites was decreased clearly. Moreover, Co-supported SiO2-MCM-36 and Al2O3-MCM-36 can effectively narrow the product distribution of FT synthesis showing clearly increased C-4-C-12 selectivity. However, the selectivity of C-21+ hydrocarbons over Co/delaminated zeolite was significantly increased. The results are well explained based on the structural and acidic properties of the MCM-22 derived zeolites together with the reduction behaviors of the catalysts. (C) 2016 Elsevier B.V. All rights reserved.