Conversion of methane to benzene over transition metal ion ZSM-5 zeolites : I. Catalytic characterization

TLDR: In this paper, the conversion of methane to benzene in the absence of oxygen has been investigated over different TMI/H-ZSM-5 zeolites (with TMI=Mo, Fe, V, W, and Cr) as a function of preparation and treatment method, the metal ion loading, and the zeolite acidity.

About: This article is published in Journal of Catalysis.The article was published on 1998-04-25 and is currently open access. It has received 264 citations till now. The article focuses on the topics: Induction period & Catalysis.

Figures

FIG. 4. (A) Effect of reduction temperature and (B) reduction time on the conversion of methane over 2.0 wt% Fe/H-ZSM-5 prepared by impregnation. The catalytic reaction was at 750◦C, 1 atm, and GHSV= 800 h−1. For experiment A, the reduction time was 6 h, whereas the reduction temperature was 500◦C for experiment B.

FIG. 5. Effect of calcination temperature on CH4 activation over 0.6 wt% Fe/H-ZSM-5 prepared by impregnation and prereduced at 500◦C for 6 h in CO. The catalytic reaction was at 750◦C, 1 atm, and GHSV= 800 h−1.

FIG. 8. Infrared spectra of 2 wt% Cr/H-ZSM-5 zeolites that contained different concentrations of Brönsted acid sites. Samples were prepared by ion exchange in 1 M solutions containing (A) NH4NO3, (B) 5 : 1 NH4NO3 : NaCl, (C) 3 : 1 NH4NO3 : NaCl, (D) 2 : 1 NH4NO3 : NaCl, and (E) NaCl. Materials were subsequently impregnated with CrO3, dried and calcined at 500◦C for 5 h.

FIG. 6. Effect of reaction temperature on the conversion of methane over 0.6 wt% Fe/H-ZSM-5 prepared by impregnation and prereduced at 500◦C for 6 h in CO. The catalytic reaction was at 1 atm and GHSV= 800 h−1.

FIG. 7. Effect of GHSV on the conversion of methane over 0.6 wt% Fe/H-ZSM-5 prepared by impregnation and prereduced at 500◦C for 6 h in CO. The catalytic reaction was at 750◦C and 1 atm.

FIG. 9. Effect of the number of Brönsted acid sites on CH4 activation over 2 wt% Cr/H-ZSM-5 prepared by impregnation and prereduced at 500◦C for 6 h in CO. The catalytic reaction was at 750◦C, 1 atm, and GHSV= 800 h−1.