(509ci) Autothermal Reactor Design and Development for the Oxidative Dehydrogenation of Ethane

Ethylene is a key platform chemical used in the production of a variety of bulk chemicals such as polyethylene, ethylene dichloride, and ethylene oxide. Despite the oxidative dehydrogenation of ethane (ODHE) being extensively investigated as an alternative to steam cracking processes currently used to produce ethylene, a reactor design that can plausibly be implemented on an industrial scale has not yet been proposed in the literature. In this work, we use a combination of theory and experiment to demonstrate that ODHE can be operated autothermally at high pressures with ambient temperature feeds and no external heat input.

A global kinetic model that accurately describes ODHE catalysis between 330- 430°C and 0-6 bar total pressure on a MoVTeNbO_x catalyst was developed using a combination of reaction kinetics experiments and mathematical modeling. Parity plots point to good agreement between model predictions and experimentally measured rates over a wide range of experimental conditions. F-values and t-values as well as the confidence intervals were utilized to evidence the global significance of proposed kinetic models. These global kinetic models were used to conduct bifurcation analysis and identify plausible regions of autothermal operation that were then validated using lab-scale experiments. Our results demonstrate that autothermal reactors can be used to achieve higher ODHE reactor productivity compared to traditional fixed-bed reactors, especially at higher pressures, with their advantages becoming more amplified for highly active catalysts. The results of the study create opportunities for the intensified production of ethene in compact, modular reactors that can operate in concert with renewable sources of electricity that are inherently intermittent in nature.