Mechanical engineers at The University of Texas at Austin have developed a new method to address the issue of climate change resulting from an unabated increase in carbon dioxide (CO2) emissions.
The idea involves trapping and locking CO2 from the atmosphere into crystalline structures called hydrates. These are compounds of water and CO2 , which form at high pressure and temperatures around the freezing temperature of water. In fact, CO2 hydrates look and feel very much like frozen ice. Hydrates are a compact way of capturing large volumes of CO2 gas for long-term storage.
While hydrates have been known for more than 200 years, and occur naturally, making hydrates in lab conditions is very challenging. The thermodynamics involved in hydrate formation and the slow reactions make it very difficult to make hydrates artificially.
Now, a team led by Associate Professor Vaibhav Bahadur has come up with a simple technique to make CO2 hydrates faster. They discovered that aluminum metal significantly speeds up hydrate formation. According to Bahadur, “You can wait for hours and even days for hydrates to form. We were therefore pleasantly surprised to discover that aluminum acts as a catalyst. What is even more interesting is that other metals do not show any benefits, so there is something magical about aluminum.”
Detailed findings and the science behind the benefits of aluminum are reported in an article in The Journal of Physical Chemistry Letters. This finding overcomes a well-known issue concerning hydrates, and Bahadur believes that it can enable the development of new carbon sequestration technology that was previously unrealizable. In his words, “We are just getting started, there is lots more to do in terms of advancing this technology. My hope is that we can offer a technological solution to the problem of climate change, and minimize global temperature rise.”
Other researchers in UT Austin’s Walker Department of Mechanical Engineering who are working on this solution include PhD students Palash Acharya, Aritra Kar, Awan Bhati and Postdoc Arjang Shahriari.
Water drops converting to CO2 hydrates
