From cleaner “cracking” to black gold

In Götz Veser’s lab at the University of Pittsburgh Swanson School of Engineering, then-PhD candidate Aime Laurent Twizerimana was pumping ethane through molten metal at temperatures below 1,000 degrees Celsius when something unexpected happened. The carbon byproduct that rose to the surface appeared “fluffy.” That byproduct turned out to be high-quality graphite.

While researching a cleaner, more efficient way to produce ethylene, Twizerimana had struck the new “black gold,” as graphite is known in high-tech and automotive industries. This graphite is a key ingredient in lithium-ion batteries, which are essential to electric vehicles, modern electronics, and green energy storage. However, current methods for producing the graphite, which require temperatures of 3,000ºC, are far from energy efficient, and today 95 percent of the material comes from China.  

Recognizing the need to produce domestic graphite and hydrogen more efficiently, the Pitt team of Veser and Twizerimana, with Assistant Professor Mohammad Masnadi and PhD student Nader Sawtarie, filed for a provisional patent and launched the startup Graphonos Materials (formerly Grapheon). The company has demonstrated its novel technology in the lab and has caught the attention of venture capitalists, most recently at the Rice Business Plan Competition, where it won a $20,000 Aramco Innovator Prize.

An unexpected discovery

“A holdup in the transition to cleaner energy is the attitude that you’re either for or against renewable energy,” said Veser, professor of chemical and petroleum engineering at the Swanson School and the Leonard Peters Faculty Fellow in the Covestro Circular Economy Program. “My research explores ways to connect the processing of fossil fuels to a more sustainable future, supporting this transition.” 

With Masnadi, who also now serves as chief sustainability officer of Graphonos Materials, Veser has been investigating new methods to separate, or “crack,” ethane, a main ingredient in the natural gas found in Western Pennsylvania. Cracking ethane into ethylene requires heat and generates solid carbon from side reactions, and the most common approach involves pumping steam into a reactor to avoid plugging the reactor tubes.

“It’s a very energy- and emission-intensive process, where carbon build-up in the reactor requires regular process shut-downs for cleaning,” said Veser, who is also chief technology officer of Graphonos Materials. “In looking for a cleaner alternative, we turned to molten metal catalysis, a technique that isn’t widely used but that has been around for almost a century already.”

Instead of using a solid metal catalyst, the researchers pumped the ethane through molten metal, where it dehydrogenates. “Molten metals have an amazing advantage,” Masnadi said. “Because of the extreme density of the liquid metals, the carbon floats out to rest on the top.”

For his PhD research, Twizerimana, now CEO of Graphonos Materials and a postdoctoral researcher at the Swanson School, was investigating this process. As he said, “It was toward the end of my PhD, and I realized that with some of the metals we used, the carbon that formed came out differently, fluffier. We decided to look more closely at that.”

Twizerimana turned to Sawtarie, a fellow graduate student who was researching the unique properties of 2D metals in Professor Susan Fullerton’s Nanoionics and Electronics Lab. “Part of my PhD research involved graphene, a form of graphite,” said Sawtarie, the chief product officer at Graphonos Materials. “I characterized the byproduct, which turned out to be incredibly valuable.”

A trip to “the Super Bowl”

“While searching for new ways to crack ethane, we found that we could produce battery-quality graphite by heating the ethane to temperatures below 1,000ºC,” Twizerimana said. “We produce graphite in a more sustainable and economically competitive process, with hydrogen generated as a valuable co-product.”

Most of the battery-quality graphite today is produced in China through an extremely energy-intensive process. Crystalline petroleum coke, called needle coke, is heated to 3,000ºC in a very slow batch process, where a single batch can take up to three weeks. Domestic graphite producers exist, using this intensive process, but the graphite is more expensive than in China, which dominates the market. 

The Pitt team developed and validated a process that spanned two Swanson School labs and produced two key ingredients for a cleaner energy future. As they launched Graphonos Materials, they found valuable support at Pitt’s Big Idea Center. The Center helps students and faculty entrepreneurs realize their ideas and develop and deliver their pitches.

This support would help lead Graphonos Materials to what Pitt Professor Christopher Wilmer calls “the Super Bowl of pitch competitions.” Of the more than 550 teams worldwide that applied to compete in the Rice Business Plan Competition, 41 were selected along with Graphonos Materials.

This April at the competition, they were one of 15 teams to reach the semi-finals and one of two teams capturing a $20,000 Aramco Innovator Prize. According to Aramco Ventures, this prize “recognizes the most forward-thinking and high-impact solutions at this year’s competition and celebrates entrepreneurs who embody this spirit of discovery and technical excellence.”

At Pitt, the team also won the $25,000 Big Idea Competition Grand Prize. Together, the prizes validated their work and its potential to transform how graphite and hydrogen are produced. “We have learned that there is a strong need for low-cost, sustainable graphite in the market,” Twizerimana said. “Now is the right time to fill it.”

“We’re raising money to develop our first fully integrated bench-scale system, which will enable us to produce kilograms per day and will give us the engineering basis to design a pilot skid,” Veser said. If successful, it will allow the team to turn Western Pennsylvania’s ethane into two products essential to the transition to cleaner energy, right here in Pittsburgh.