Optimum Yield of the Purely Heterogeneous Oxidative Dimerization of Methane
- Creators
- Colussi, A. J.
- Amorebieta, V. T.
Abstract
The optimal C_2-yield per pass for the purely heterogeneous catalytic oxidation of methane by O_2 on Sm_2O_3 under continuous cofeed operation: η_(opt) ≤ 0.22 ± 0.03, is computed from actual kinetic data for all the pseudoelementary chemical reactions involved. The optimization dispenses with adjustable kinetic parameters, and explores the combined effects of CH_4 and O_2 flow rates, catalyst mass, residence time, and temperature variations on the objective function η = methane conversion × C_2-selectivity for the scheme: CH_4 (+O_2) ⇒ CH_3(→) 1/2 C_2H_6⇒ 1/2 C_2H_4⇒ CO. The fact that the derived η_(opt) value essentially coincides with the largest C_2-yields reported on a myriad catalysts under vastly different conditions: (1) proves that the ceiling to selectivity is solely determined by the competition among heterogeneous processes and (2) implies a substrate-independent selectivity pattern for the species formed in O_2 dissociative chemisorption. We briefly analyze the physical basis of these propositions and of the prospects of improving C_2-yields beyond 25%.
Additional Information
© 1997 Academic Press. Received November 26, 1996; revised February 28, 1997; accepted March 3, 1997. This project was financially supported by CONICET/Argentina under Grant PID1131/91.Additional details
- Eprint ID
- 58501
- Resolver ID
- CaltechAUTHORS:20150623-154802540
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)
- PID1131/91
- Created
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2015-07-29Created from EPrint's datestamp field
- Updated
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2021-11-10Created from EPrint's last_modified field