The gas phase oxidative dehydrogenation of ethane (ODHE) has been investigated, both experimentally and through kinetic modeling and simulation, as a potential alternative to steam cracking for ethylene production. The experiments were carried out at isothermal conditions and atmospheric pressure by using a quartz tube flow reactor (2 mm i.d.) with a volume of 0.110 mL. A gas phase kinetic model with 134 elementary reaction steps and 25 species was adopted from the literature, and the parameters were adjusted by best fitting of the experimental data based on the sensitivity analysis of the kinetic model. Further, the model was reduced based on the contribution analysis and a kinetic model of 41 steps involving 23 gas phase species was established. The kinetic analysis of the gas phase ODHE reaction is performed by means of the established kinetic model to provide the reaction pathways for ethylene and other byproducts formation, providing a better understanding of the radical chemistry for limiting the ethylene selectivity. The reactor simulations are performed under different conditions such as C 2 H 6 /O 2 ratios and temperatures to search for the upper bound of the ethylene yield in the gas phase ODHE. An upper bound ethylene yield of 53.5% (C 2 H 4 selectivity, 65.4%) is predicted at 1173 K and C 2 H 6 /O 2 = 3.33 with a residence time of 0.1 s at atmospheric pressure.
The autothermal gas-phase oxidative dehydrogenation of ethane (ODHE) in a tubular reactor was analyzed by one-dimensional (1D) and two-dimensional (2D) reactor simulations coupling with a detailed kinetic model, where effects of the reactor configuration and operating conditions such as the C2H6/O2 ratio, inlet temperatures, and oxygen distribution on the ethylene yield were analyzed and optimized. An inlet temperature of 1023 K and a C2H6/O2 ratio of 3.3 were found as the best-operating conditions for the gas-phase oxidative dehydrogenation of ethane with autothermal operations. Multiple injections of oxygen feed are analyzed and used to optimize the ethylene yield using an overall C2H6/O2 ratio of 3.3. An ethylene yield of 57.8% (C2H4 selectivity 70.2%) is predicted for an inlet temperature of 1023 K. The results demonstrated the importance of small gradients of oxygen and temperature in the reactor for both the axial and radial directions to gain a high ethylene yield. A multitubular reactor with a relatively small diameter and multiple axial oxygen injections is recommended.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.