NETL and collaborators are developing a technology for more cost-efficient and time-saving production of graphite — a critical mineral needed for high-value energy and consumer products like batteries, cement and polymer composites — from various grades of petroleum coke, a solid, carbon-rich material byproduct of oil refining.

Graphite is used in a wide variety of products. It is in batteries, pencils, lubricants, crucibles, foundry facings, polishes, brushes for electric motors, and even cores of nuclear reactors. Its high thermal and electrical conductivity make it a key part of steelmaking, where it is used as electrodes in electric arc furnaces.

While industries currently process high-grade petroleum coke for use in high-value products that are essential for energy security, low-grade petroleum coke has not been suitable for graphite production because of its high sulfur content.

NETL’s Congjun Wang explained that, working with researchers at Texas A&M and a company named Oxbow Carbon, the technology in development uses iron-based catalysts and heat in a process known as catalytic graphitization to change carbon into graphite from a range of petroleum coke grades.

A catalyst is a substance that speeds up a chemical reaction. During a chemical reaction, the bonds between the atoms in molecules are broken, rearranged, and rebuilt, recombining the atoms into new molecules. Using catalysts leads to faster, more energy-efficient chemical reactions.

Wang explained that “Our preliminary data shows that iron-based catalysts enable graphitization of a wide range of petroleum coke grades, complete with a catalyst recovery process. We believe the technology is successful at a much lower temperature and shorter process time to produce high-value graphite from low grade petroleum coke than traditional processes. The improvements can lead to lower costs and processing times for synthetic graphite production.”

Wang said it should also enable domestic supply chain security for the nation’s graphite needs.

In addition, the research features catalyst recycling, rapid quality control, testing in key applications like Li-ion battery electrodes and techno-economic analysis.

NETL’s Christopher Matranga added that the project plans to test the technology in a pilot plant and, if successful, eventual commercialization.

“We believe that these advancements will ultimately help establish a secure domestic supply chain for graphite, an increasingly important critical mineral,” Matranga said.

NETL is a U.S. Department of Energy (DOE) national laboratory dedicated to advancing the nation's energy future by creating innovative solutions that strengthen the security, affordability and reliability of energy systems and natural resources. With laboratories in Albany, Oregon; Morgantown, West Virginia; and Pittsburgh, Pennsylvania, NETL creates advanced energy technologies that support DOE’s mission while fostering collaborations that will lead to a resilient and abundant energy future for the nation.