Articles tagged with "graphite"
US lab makes graphite from coal waste, can be used in nuclear reactor
The US National Energy Technology Laboratory (NETL) has developed a novel low-temperature catalytic process to produce high-quality graphite from coal waste and other carbon-rich materials such as coal char, bio-char, petroleum coke, and plastic waste. This innovative method uses earth-abundant catalysts like iron to facilitate the formation of highly crystalline graphite at temperatures below 1,500 degrees Celsius, significantly lower than the conventional 3,000 degrees Celsius. The process is also faster, reducing production time from weeks to hours, and the catalyst can be recycled indefinitely, improving economic viability. Graphite produced through this method performs comparably to commercial graphite in applications such as lithium-ion battery anodes. Graphite is classified as a critical mineral in the United States due to its essential role in manufacturing, including battery electrodes, steel production, and nuclear power, combined with supply chain vulnerabilities. Currently, the global graphite market is heavily dominated by China, which produces about 70% of natural graphite and 60% of synthetic graphite.
materialsgraphitecoal-wastebattery-technologyenergy-storagecritical-mineralsmanufacturing-innovationNuclear reactor fears eased as US lab clears graphite of safety risk
Researchers at Oak Ridge National Laboratory (ORNL) have resolved a decades-old debate regarding the impact of microscopic pores in graphite used in nuclear reactors. Their study, published in the journal Carbon, confirms that the natural porosity within graphite blocks does not affect the material’s atomic vibrations or its fundamental neutron moderation properties. This finding is significant because graphite has been a key component in nuclear reactors since the first reactor in 1942, valued for its ability to withstand extreme temperatures and slow down neutrons to sustain controlled nuclear chain reactions. The research provides greater confidence in the safety and design of current and next-generation reactors, including very high-temperature reactors (VHTRs) and molten salt reactors. The study addressed a critical flaw in previous models that treated graphite porosity by randomly removing atoms, which artificially distorted the material’s vibrational properties and led to overestimations in reactor criticality calculations. Using advanced neutron scattering experiments combined with machine-learned atomic potentials, the ORNL team demonstrated that the increased neutron
energynuclear-reactorsgraphitematerials-scienceneutron-scatteringreactor-safetyhigh-temperature-reactorsMIT study could help predict graphite lifespan in nuclear reactors
A recent MIT study has advanced understanding of how graphite, a critical material in nuclear reactors, behaves under radiation. Graphite is widely used as a neutron moderator and reflector in reactors, playing a key role in sustaining controlled nuclear chain reactions. However, radiation exposure causes graphite to deform through swelling, shrinking, and cracking, complicating predictions of its lifespan. The MIT team applied a statistical method called the Weibull Distribution alongside X-ray scattering techniques to analyze irradiated graphite samples from Oak Ridge National Laboratory. Their research revealed unexpected pore behavior: initially, pores fill as graphite degrades, but over prolonged irradiation, a recovery or annealing process occurs where new pores form and existing pores smooth and enlarge, influencing the material’s volume changes. This discovery sheds light on graphite’s complex composite structure—comprising crystalline filler particles, a less crystalline binder matrix, and pores ranging from nanometers to microns—that affects its radiation response. The study’s findings could lead to more accurate, non-destructive predictions of graphite’s
materialsgraphitenuclear-reactorsradiation-damagematerial-lifespancomposite-materialsenergy-materialsChina Dominates Global Trade of Battery Minerals - CleanTechnica
battery-mineralslithiumcobaltgraphitebattery-supply-chainenergy-storageclean-technology