As a ChemE at Lehigh, you really get to have well rounded ChemE experience. Other than exciting technical plant design and hands-on lab operations, you get to learn much more. For my CHE 376, Energy: Issues and Technology class, we were required to give a 20 minuted quick presentation on a type of technology that we can use that will address some of the current energy issues. My group and I decided to take on the topic of Syngas Producion via Co-electrolysis of CO2 and H2O. We think it’s a good topic because this technology was able to successful make use of the CO2 in our atmosphere, and convert it into something useful such as CO, H2 (Syngas), and O2. As you know, CO2 caused global warming is currently a major problem for this world. And there is a increase in energy demand with increasing population around the world. By the electrolysis of CO2 into syngas, the energy demand would be alleviated while maintaining a sustainable world.
Co-electrolysis of CO2 and H2O is a two step process where the first step converts CO2 and H2O to CO, H2 and O2, and the second step is the production of liquid fuel through Fisher-Tropsch process. The Fisher-Tropsch process converts a mixture of CO and H2 into liquid hydrocarbons, which can be used in cars and other industrial applications. Generally, the closed loop process goes like this:
In the above diagram, the CO2 is captured from the atmosphere and it goes through a co-electrolysis process in a solid oxide cell to produce syngas. And then an electrolysis-based synthetic fuel production process, with fischer-Tropsch Fuel synthesis, produces synthetic gasoline. This process sounded amazing and all. However, there’s a few cons associated with it. First of all, the dominant costs of this process are the electricity cost and capital cost of the electrolyzer, which are ridiculously expensive. In addition, capturing CO2 from atmosphere is very difficult and sometime impossible. Other issues such as electrode corrosion and catalyst for ideal conversion also posts challenges to this technology.
If/When additional technology advancement takes place and make this process more viable, the system should be able to operate 70% electricity-to-liquid fuel efficiency and that the price of electricity needed to produce competitive synthetic gas is 2-3 US cents per kWh. We’re still doing more researches on this topic, and I hope to find some idea that could potentially make this process more appealing.