Thinking Inside of the Box

Carbon capture and storage technologies trap the carbon emissions from an industrial source such as a power plant to limit the emissions that can enter the atmosphere. As climate change becomes an evermore concerning issue, so too does this technology become an increasingly popular research topic. 

Despite the excitement and rush to implement carbon capture, researchers still have a lot of work to do to make carbon capture accessible, stable and environmentally friendly. At the University of California, Davis, one student team of chemical engineers is thinking inside the box to do it.  

Cubes for Carbon Capture

The ChemECube student team is a competition sub-group of the American Institute of Chemical Engineering, or AIChE, where team members are challenged to create a 1-cubic-foot power plant that solves a specific problem. 

In March 2024, a team of eight UC Davis students, including third-year chemical engineering students, Nicholas Braga and Ariana Amjad, took on the identified challenge: direct air capture.  

The first step in the ChemECube competition was a virtual competition held in April, which would determine whether or not a team could compete as a finalist.  

“We had to make a presentation based on what we would be making if we were in the competition,” said Braga. “That meant creating a virtual 3D model of what our design would look like, outlining how it would work, defining the safety measures and explaining some of the economic implications.” 

Science in a Box

Out of 38 teams that competed at AIChE’s qualifying competition in April 2024, the UC Davis team was one of 18 selected to go to the next round. From there, they had until AIChE’s Annual Student Conference in October to build their cube and test it.  

“For direct air capture, you want to selectively take carbon dioxide away from the environment,” Braga said . “We used something called sodium mordenite. It exists naturally, but you can also make it synthetically in order to fine-tune properties that will increase how much CO2 it can capture.”  

They then 3D printed two cylinder vessels that had the sodium mordenite in them and at the top and bottom of the cylinders there were inlets and outlets for air to be pumped into it. One of the cylinders would have air running through it and the other would be more static.  

“One would be regenerating, meaning that we would be letting the CO2 go from the absorbent material so that we can collect it as a pure stream of carbon dioxide,” Braga said. “The other cylinder would be the one that was capturing, or having ambient air run through it. The point of that was to keep cycling between those two, so one would be regenerating while one would be capturing.” 

After a certain amount of time, a system of valves controlled by an Arduino would switch which cylinder was capturing and which was regenerating. The reason this happens is because they always need a pure CO2 source, which is what the regenerating cylinder was doing.  

This was supposed to represent how the system would work if it was scaled up into a life-size direct air capture plant.  

Upping the Cube Game  

The AIChE Annual Student Competition took place in San Diego in October and consisted of two days of competition: business day and engineering day.  

On “business day,” teams were required to pitch what they built by attempting to sell their product to mock investors. On “engineering day,” they operated their cube against other competitors’ cubes and presented their research poster to explain the design and chemistry behind their cube.  

The UC Davis team placed seventh out of 18 teams including the University of California, Los Angeles, Massachusetts Institute of Technology and Virginia Tech. They look forward to competing again this year under the same problem theme. The prompt states they must make a physical change to their design.  

“Given that we have seen the designs that beat our designs, we are striving to find more innovative and efficient solutions through scientific literature research and creativity,” Braga said. 

Some of that research is in ChemECube’s own figurative backyard. At UC Davis, professors and researchers are also innovating ways to solve this global problem. Associate Professor of Chemical Engineering Ambar Kulkarni, who advised the ChemECube team, investigates catalysts as a means of capturing carbon, while Assistant Professor of Materials Science and Engineering Erika La Plante has started a company dedicated to capturing carbon and turning it into hydrogen. Elsewhere, Sabbie Miller, an associate professor of civil and environmental engineering, is researching ways of storing carbon in building materials like concrete.  

Building the Team

The qualifying presentation will take place at the end of April. As they approach the competition they are looking for more members to join their team.  

“If you're interested, if you're passionate, we want more people to help out,” said Amjad, Braga’s teammate. “For the competition team, we want people who are committed and know a little about the design process.” 

This competition covers a large range of majors and tasks that require assistance from other areas of study, so the ChemECube team also hopes to fill that gap.  

“Our long-term goal is to get a lot of other fields and majors involved, because this competition, it's not only just for chemical engineers,” Amjad said. “As a chemical engineer, I'm learning a lot about electrical engineering and mechanical engineering. I'm learning a lot about business, economics and environmental science. I think students in those fields would benefit greatly from this experience.”