Low-temperature catalytic upcycling of petroleum coke into battery-grade graphite

Abstract Petroleum coke, a low-value byproduct of oil refining, is widely used as an industrial fuel with significant carbon and sulfur emissions. Converting petroleum coke into battery-grade graphite reduces its environmental footprint while meeting the rising demand for sustainable energy materials. Conventional graphitization, however, requires extreme temperatures (>3000 °C) and long processing times, limiting industrial adoption. We demonstrate a catalytic graphitization process that transforms the coke into graphite at <1600 °C within hours, using iron (Fe) as a recoverable and reusable catalyst. Structural analyses confirm a high degree of graphitization, and electrochemical testing shows lithium-ion battery anode performance comparable to commercial graphite. By operating at reduced temperature and shortening reaction time, our method theoretically lowers energy by more than 9-fold as compared to the conventional process. By reducing energy demand and enabling resource recovery, this method offers a scalable, energy-efficient route to valorize petroleum coke. Our results highlight catalytic graphitization as a practical pathway to reduce emissions from oil refining byproducts while supporting sustainable energy storage technologies.