A new carbon capture and storage technique has been developed by an international team of researchers, led by Professor Cafer T. Yavuz from King Abdullah University of Science and Technology (KAUST), along with Prof. Bo Liu from University of Science and Technology of China (USTC), and Prof. Qiang Xu from Southern University of Science and Technology (SUSTech).
The team focused on methane hydrate’s ability to capture and trap gas molecules, including carbon dioxide, under high pressure. However, recreating these conditions in the lab is difficult, and the approach requires a lot of energy because the methane-ice solid needs to be refrigerated.
To address these issues, the scientists used a salt called guanidinium sulfate to create lattice-like structures, or clathrates, that mimic the methane hydrate’s activity. These clathrates can trap CO2 molecules and are an energy-efficient way to contain greenhouse gases.
According to Cafer Yavuz, the guanidinium sulfate organizes and traps CO2 molecules without reacting with them, resulting in a rare example of a stable and non-corrosive clathrate at ambient temperature and pressure. This feature is highly desirable compared to other solutions such as ethanol amine and ammonia that are commonly used in carbon capture.
Previous methods of capturing carbon dioxide, such as chemisorption, involved the formation of chemical bonds between CO2 molecules and surfaces. While effective, these methods were costly due to the energy required to break down the chemical bonds. In contrast, the salt-based clathrate structure discovered by an international team of researchers, including Professors Cafer T. Yavuz, Bo Liu, and Qiang Xu, uses low-energy physisorption processes to capture CO2 without interference from water or nitrogen. This breakthrough offers a promising avenue for carbon capture and storage technologies, with the added benefit of rapidly solidifying CO2.
This novel approach allows for the storage and transportation of carbon dioxide in a solid state, rather than the conventional methods of dry ice or compressed gas cylinders. The salt clathrate method yields a high volume-to-weight capacity, making it the least energy-intensive option for real-world applications. According to Professor Yavuz, this innovation has far-reaching impacts, as industries and entities seek energy-efficient ways to capture, store, and transport CO2 without significant energy penalties.
This new method has the potential to significantly contribute to the fight against climate change, and the research team is optimistic about its potential for future improvements in stability, recyclability, sorption capacity, selectivity, and reducing regeneration energy penalties and costs. The study was conducted at several institutions, including the Southern University of Science and Technology, University of Science and Technology of China, and King Abdullah University of Science and Technology, with findings published in the Cell Reports Physical Science journal.