Non-oxidative methane aromatization by bimetallic (La, Co, Pd and Pt) M-Zn/HZSM-5: Impact of propane addition

Document Type : Article

Authors

1 Catalyst Research Group, Petrochemical Research and Technology Company, National Petrochemical Company

2 Chemical Engineering Department, Amirkabir University of Technology

3 Department of Civil and Environmental Engineering, University of Alberta, Edmonton

Abstract

The non-oxidative aromatization of methane was studied over M-Zn/HZSM-5 (M=La, Co, Pd, and Pt) catalysts using propane as a co-reactant. The catalysts were characterized by BET, SEM, NH3-TPD and XRD techniques. Catalytic tests were performed in a fixed-bed reactor at 823 K, using a mixture of methane, propane, and nitrogen with ratio of 6/1/1.3, respectively. Propane conversion was above50% and remained stable in the first 12 hours on stream; however, the methane conversion rapidly dropped from a high of about 10% to zero within 4 hours, implying the absence of a stoichiometric reaction between the reactants. Both zinc and the second metal (M) had a beneficial effect on aromatic selectivity and Pt-Zn/HZSM-5 exhibited the highest aromatic yields and catalyst stability. The results of the present study showed that co-feeding of methane with propane cannot successfully induce methane to participate in aromatization reactions.

Keywords

Main Subjects


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