New technology has been developed that uses nuclear waste to generate electricity in a nuclear-powered battery. A team of physicists and chemists from the University of Bristol have grown a man-made diamond that, when placed in a radioactive field, is able to generate a small electrical current.
The development could solve some of the problems of nuclear waste, clean electricity generation and battery life.
This innovative method for radioactive energy was presented at the Cabot Institute’s sold-out annual lecture – ‘Ideas to change the world’- on Friday, 25 November.
Unlike the majority of electricity-generation technologies, which use energy to move a magnet through a coil of wire to generate a current, the man-made diamond is able to produce a charge simply by being placed in close proximity to a radioactive source.
Tom Scott, Professor in Materials in the University’s Interface Analysis Centre and a member of the Cabot Institute, said: “There are no moving parts involved, no emissions generated and no maintenance required, just direct electricity generation. By encapsulating radioactive material inside diamonds, we turn a long-term problem of nuclear waste into a nuclear-powered battery and a long-term supply of clean energy.”
The team have demonstrated a prototype ‘diamond battery’ using Nickel-63 as the radiation source. However, they are now working to significantly improve efficiency by utilising carbon-14, a radioactive version of carbon, which is generated in graphite blocks used to moderate the reaction in nuclear power plants. Research by academics at Bristol has shown that the radioactive carbon-14 is concentrated at the surface of these blocks, making it possible to process it to remove the majority of the radioactive material. The extracted carbon-14 is then incorporated into a diamond to produce a nuclear-powered battery.
The UK currently holds almost 95,000 tonnes of graphite blocks and by extracting carbon-14 from them, their radioactivity decreases, reducing the cost and challenge of safely storing this nuclear waste.
Dr Neil Fox from the School of Chemistry explained: “Carbon-14 was chosen as a source material because it emits a short-range radiation, which is quickly absorbed by any solid material. This would make it dangerous to ingest or touch with your naked skin, but safely held within diamond, no short-range radiation can escape. In fact, diamond is the hardest substance known to man, there is literally nothing we could use that could offer more protection.”
Despite their low-power, relative to current battery technologies, the life-time of these diamond batteries could revolutionise the powering of devices over long timescales. Using carbon-14 the battery would take 5,730 years to reach 50 per cent power, which is about as long as human civilization has existed.
Professor Scott added: “We envision these batteries to be used in situations where it is not feasible to charge or replace conventional batteries. Obvious applications would be in low-power electrical devices where long life of the energy source is needed, such as pacemakers, satellites, high-altitude drones or even spacecraft.
“There are so many possible uses that we’re asking the public to come up with suggestions of how they would utilise this technology by using #diamondbattery.”
Rutgers professor Ashutosh Goel invents way to contain radioactive iodine
How do you handle nuclear waste that will be radioactive for millions of years, keeping it from harming people and the environment?
It isn’t easy, but Rutgers researcher Ashutosh Goel has discovered ways to immobilize such waste – the offshoot of decades of nuclear weapons production – in glass and ceramics.
Goel, an assistant professor in the Department of Materials Science and Engineering, is the primary inventor of a new method to immobilize radioactive iodine in ceramics at room temperature. He’s also the principal investigator (PI) or co-PI for six glass-related research projects totaling $6.34 million in federal and private funding, with $3.335 million going to Rutgers.
“Glass is a perfect material for immobilizing the radioactive wastes with excellent chemical durability,” said Goel, who works in the School of Engineering. Developing ways to immobilize iodine-129, which is especially troublesome, is crucial for its safe storage and disposal in underground geological formations.
The half-life of iodine-129 is 15.7 million years, and it can disperse rapidly in air and water, according to the U.S. Environmental Protection Agency. If it’s released into the environment, iodine will linger for millions of years. Iodine targets the thyroid gland and can increase the chances of getting cancer.
Among Goel’s major funders is the U.S. Department of Energy (DOE), which oversees one of the world’s largest nuclear cleanups following 45 years of producing nuclear weapons. The national weapons complex once had 16 major facilities that covered vast swaths of Idaho, Nevada, South Carolina, Tennessee and Washington state, according to the DOE.
The agency says the Hanford site in southeastern Washington, which manufactured more than 20 million pieces of uranium metal fuel for nine nuclear reactors near the Columbia River, is its biggest cleanup challenge.
Hanford plants processed 110,000 tons of fuel from the reactors. Some 56 million gallons of radioactive waste – enough to fill more than 1 million bathtubs – went to 177 large underground tanks. As many as 67 tanks – more than one third – are thought to have leaked, the DOE says. The liquids have been pumped out of the 67 tanks, leaving mostly dried solids.
The Hanford cleanup mission commenced in 1989, and construction of a waste treatment plant for the liquid radioactive waste in tanks was launched a decade later and is more than three-fifths finished.
“What we’re talking about here is highly complex, multicomponent radioactive waste which contains almost everything in the periodic table,” Goel said. “What we’re focusing on is underground and has to be immobilized.”
Goel, a native of Punjab state in northern India, earned a doctorate in glasses and glass-ceramics from the University of Aveiro in Portugal in 2009 and was a postdoctoral researcher there. He worked as a “glass scientist” at the Pacific Northwest National Laboratory in 2011 and 2012, and then as a senior scientist at Sterlite Technologies Ltd. in India before joining the Rutgers faculty in January 2014.
The six projects he’s leading or co-leading are funded by the DOE Office of River Protection, National Science Foundation and Corning Inc., with collaborators from Washington State University, University of North Texas and Pacific Northwest National Laboratory.
One of his inventions involves mass producing chemically durable apatite minerals, or glasses, to immobilize iodine without using high temperatures. A second innovation deploys synthesizing apatite minerals from silver iodide particles. He’s also studying how to immobilize sodium and alumina in high-level radioactive waste in borosilicate glasses that resist crystallization.
At the Hanford site, creating glass with radioactive waste is expected to start in around 2022 or 2023, Goel said, and “the implications of our research will be much more visible by that time.”
“It depends on its composition, how complex it is and what it contains,” Goel said. “If we know the chemical composition of the nuclear waste coming out from those plants, we can definitely work on it.”
First evidence for new molecular structure could open doors to chemical solutions for environmental problems
Indiana University researchers have reported the first definitive evidence for a new molecular structure with potential applications to the safe storage of nuclear waste and reduction of chemicals that contaminate water and trigger large fish kills.
The study, which was published online Oct. 6 in the German scientific journal Angewandte Chemie International Edition, provides experimental proof for the existence of a chemical bond between two negatively charged molecules of bisulfate, or HSO4.
The existence of this structure — a “supramolecule” with two negatively charged ions — was once regarded as impossible since it appears to defy a nearly 250-year-old chemical law that has recently come under new scrutiny.
“An anion-anion dimerization of bisulfate goes against simple expectations of Coulomb’s law,” said IU professor Amar Flood, who is the senior author on the study. “But the structural evidence we present in this paper shows two hydroxy anions can in fact be chemically bonded. We believe the long-range repulsions between these anions are offset by short-range attractions.”
Flood is a professor in the IU Bloomington College of Arts and Sciences’ Department of Chemistry. The first author on the study is Elisabeth Fatila, a postdoctoral researcher in Flood’s lab.
In molecular chemistry, two monomer molecules connected by a strong covalent bond are called a “dimer.” (A polymer is a chain of many monomers.) In supramolecular chemistry, the dimers are connected by many weak non-covalent bonds. A negatively charged particle is an anion.
A key part of Coulomb’s law is the idea that two molecules with the same charge create a repellent force that prevents chemical bonding — like two magnets with the same end put into close contact. But recently, experts have begun to argue that negatively charged molecules with hydrogen atoms, such as a bisulfate — composed of hydrogen, sulfur and oxygen – can also form viable chemical bonds.
“Although supramolecular chemistry started out as an effort to create new molecular hosts that hold on to complementary molecular guests through non-covalent bonds, the field has recently branched out to explore non-covalent interactions between the guests in order to create new ‘chemical species,'” Fatila said. The negatively charged bisulfate dimer in the IU study employs a self-complementary, anti-electrostatic hydrogen bond.
The molecule’s existence is made possible through encapsulation inside a pair of cyanostar macrocycles, a molecule previously developed by Flood’s lab at IU. Fatila and colleagues were trying to bind a single bisulfate molecule inside the cyanostar; the presence of two negatively charged bisulfate ions was a surprise.
“This paper is inspirational because it may launch a new approach to supramolecular ion recognition,” said Jonathan Sessler, a professor of chemistry at the University of Texas at Austin who was not involved in the study. “I expect this will be the start of something new and important in the field.”
The ability to produce a negatively charged bisulfate dimer might also advance the search for chemical solutions to several environmental challenges. Due to their ion-extraction properties, the molecules could potentially be used to remove sulfate ions from the process used to transform nuclear waste into storable solids — a method called vitrification, which is harmed by these ions — as well as to extract harmful phosphate ions from the environment.
“The eutrophication of lakes is just one example of the serious threat to the environment caused by the runoff of phosphates from fertilizers,” Flood said, referring to uncontrolled plant growth that results from excess phosphate nutrients running into lakes and ocean. When these chemicals get into the water supply as runoff from fertilizer — produced by dairy farms and used to increase crop yields — they can trigger massive algae blooms that poison water supplies and kill fish in large numbers.
In August, Flood was also named the principal investigator on a new, separate grant from the National Science Foundation to specifically focus on removing these substances from the environment. The three-year, $600,000 award is a collaboration with Heather Allen, a professor at The Ohio State University, which is near a part of the country that has recently experienced large algae blooms due to agricultural runoff into Lake Erie.
During the existence of nuclear power industry a large number of channel uranium-graphite nuclear power reactors was built across the world. Only Russia operates 4 units of the Leningrad Nuclear Power Plant, 4 units of Kursk NPP, 3 units of Smolensk NPP and 4 units of Bilibino NPP. Also, 13 industrial uranium-graphite reactors were built (IUGR) have been built. To date, they all are on the output stage of the operation or decommissioning preparation. While, approximately 250,000 tons of irradiated graphite are accumulated in the world, including ~ 60,000 tons in Russia. Due to the specificity of irradiated graphite the treatment of this type of radioactive waste has not been determined yet.
At the moment, the problem of irradiated nuclear graphite has been partially solved only for a select group of industrial uranium-graphite reactors. This is possible by referring graphite waste to “special waste”. Thus, in September 2015 it was successfully completed a pilot project to establish a point of long-term preservation of special waste at the site of the industrial uranium-graphite nuclear EI-2 reactor. To implement this project the experts of JSC “PD UGRC” developed and patented the unique technology of IUGR output of operation. For a long time they together with leading institutions (IPCE RAS, NIKIET OKBM, MEPI, VNIINM, Institute of Nuclear Power Plant and others) have conducted R & D to develop techniques and technical solutions to treat graphite waste.
However, this technology is not applicable for most reactors
“From these reactors it is necessary to extract graphite, then process to remove the most active radionuclides. Therefore, it is required to develop technologies, devices and hardware systems to reduce radioactive waste activity, which will make disposal of graphite economically profitable,” explains Evgeniy Bespala, a PhD student from the Department of Technical Physics. – Disposal of different classes of waste has a different price: the price for disposal of high-level, intermediate-level and low-level waste differs enormously. If we reduce the amount of radioactive nuclides in reactor graphite, the cost of its disposal will be economically feasible.