Ethylene and power cogeneration from proton ceramic fuel cells (PCFC) : a thermo-electrochemical modelling study

Abstract

Ethylene is a vital chemical worldwide but its production is very energy-intensive with high CO2 emissions. C2H6-fueled proton ceramic fuel cells (PCFCs) are promising electrochemical processes for cogeneration of ethylene and electric power with high performance and low emission. Herein, a tubular thermos-electrochemical model is established to investigate the characteristics of C2H6-fueled PCFC. Parametric studies are performed to examine the effects of operating voltage, inlet fuel flow rate, and inlet temperature on PCFC cogeneration performance. PCFC under open-circuit voltage (OCV) condition at 700 °C, the ethane conversion and ethylene selectivity are 15.69% and 99.47%, respectively. The ethylene production is enhanced by the electrochemical reaction. At 0.4 V and 700 °C, the conversion of ethane is increased to 32.59% and the PCFC can deliver a peak power density of 146.12 mW cm−2. Increasing the inlet temperature significantly improves the cogeneration performance of PCFC but also increases the temperature gradient in the cell. In addition, H2 depletion in the anode results in local electrochemical performance degradation. The results demonstrate the enhanced ethylene production by electrochemical processes and the operating and structural parameters can be optimized in the subsequent study to further improve ethylene production.