Methane dehydroaromatization over Mo-modified H-MFI for gas to liquid catalysts.
For direct gas to liquid (GTL), a novel process producing energy sources for methane dehydroaromatization is needed. Supporting MoO3 on H-MFI zeolite shows the high catalytic capacity and a selective activity for dehydroaromatization of methane to benzene at 973 K in a fixed bed reactor. On the other hand, deactivation by coke on the active sites in all the catalysts is formed during the reaction. H2 co-feed suppressed the deactivation, which is probably due to the decrease in coking amount. Mo K-edge X-ray absorption fine structure (XAFS) results showed the formation of dispersed Mo2C species with low crystallinity after dehydroaromatization. Mo L(III)-edge XANES (X-ray absorption near-edge structure) indicated the formation of active Mo species including Mo2C and Mo-oxycarbide (MoOxCy), where the redox state should be independent in the absence/presence of H2. It is concluded that Mo-oxycarbide species act as highly active species, and their stability affected the durable activity in the presence of H2.
Department of Applied Chemistry, Saitama Institute of Technology, Fukaya, Japan. aritani@sit.ac.jp
Hirofumi
H
Aritani
Hiromi
H
Shibasaki
Hitoshi
H
Orihara
Atsushi
A
Nakahira
D002384:Catalysis; D005740:Gases / Q000737:chemistry*; D008697:Methane / Q000737:chemistry*; D008982:Molybdenum / Q000737:chemistry*; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry; D014961:X-Ray Diffraction; D017641:Zeolites / Q000737:chemistry*
D005740:Gases; D017641:Zeolites; D008982:Molybdenum; D008697:Methane; D010100:Oxygen