SoylentNews is people
SoylentNews
Chemists have found a new use for the waste product of nuclear power - transforming an unused stockpile into a versatile compound which could be used to create valuable commodity chemicals as well as new energy sources.
Depleted uranium (DU) is a radioactive by-product from the process used to create nuclear energy. Many fear the health risks from DU, as it is either stored in expensive facilities or used to manufacture controversial armour-piercing missiles.
But, in a paper published in the Journal of the American Chemical Society, Professor Geoff Cloke, Professor Richard Layfield and Dr Nikolaos Tsoureas, all at the University of Sussex, have revealed that DU could, in fact, be more useful than we might think.
By using a catalyst which contains depleted uranium, the researchers have managed to convert ethylene (an alkene used to make plastic) into ethane (an alkane used to produce a number of other compounds including ethanol).
Their work is a breakthrough that could help reduce the heavy burden of large-scale storage of DU, and lead to the transformation of more complicated alkenes.
Prof Layfield said: "The ability to convert alkenes into alkanes is an important chemical reaction that means we may be able to take simple molecules and upgrade them into valuable commodity chemicals, like hydrogenated oils and petrochemicals which can be used as an energy source.
"The fact that we can use depleted uranium to do this provides proof that we don't need to be afraid of it as it might actually be very useful for us."
Journal Reference:
Nikolaos Tsoureas, Laurent Maron, Alexander F. R. Kilpatrick, Richard A. Layfield, F. Geoffrey N. Cloke. Ethene Activation and Catalytic Hydrogenation by a Low-Valent Uranium Pentalene Complex. Journal of the American Chemical Society, 2019; 142 (1): 89 DOI: 10.1021/jacs.9b11929
(Score: 2) by Immerman on Monday January 13 2020, @04:08PM (2 children)
>If it is highly radioactive that means it is still fuel.
Actually, no. Most nuclear fuel is not appreciably radioactive, it's the fission products created by the reaction (the waste) that are radioactive, and they're pretty reliably not fissile, so can't be used as nuclear fuel. They can be used in far lower power radiothermal batteries and the like, .
There is a related issue though that you might be thinking of: most nuclear "waste" is in fact still perfectly good fuel - most modern reactors only use about 5-10% of the fuel before the waste products poison the reaction so badly that the fuel can no longer sustain a chain reaction and needs to be replaced. In a sane world that fuel would be reprocessed, extracting the 5-10% of short-lived highly radioactive waste for disposal, and sending the rest back to be re-used in the reactor as perfectly good fuel. It's a dangerous and expensive process, but was actually standard in the early days of nuclear power, before advances in uranium mining and refining technologies made producing fresh fuel substantially cheaper than reprocessing. *
Which gets us to the current situation - rather than just sequestering short-lived, highly radioactive waste that would be safe to handle within a few centuries, we're storing it thoroughly mixed with 10x as much fission fuel, which fissions in response to some of the radiation, producing fresh waste products in a process that will ensure it remains dangerously radioactive for millions of years. But we do intentionally store the "waste" in ways that will make it relatively easy for our descendants to extract and reprocess it somewhere down the line...aside from the ridiculous radiation levels at least.
* Alternatively it's possible to build reactors that "burn" (almost) all the fuel in a single pass, drastically reducing the amount of reprocessing needed to only dispose of actual waste.
(Score: 0) by Anonymous Coward on Monday January 13 2020, @04:39PM (1 child)
Actually, yes. If it is meaningfully radioactive (enough to be dangerous) then it is a possible source of energy, ie fuel.
(Score: 2) by Immerman on Monday January 13 2020, @04:58PM
Not nuclear (fission or fusion) fuel though. And the energy that can be extracted from it is almost nonexistent compared to what was available in the original fuel. Nobody is going to be shutting down uranium mining in favor of converting radiation from waste into energy - all the waste produced by the entire world to date probably doesn't produce as much power as a single decent-sized fission reactor. Not to mention most of the radioactivity disappears quickly - within a few decades you'd only be getting a fraction of the power it's releasing today.