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China Power

China Achieves Thorium-Uranium Conversion Within Molten Salt Reactor (scmp.com) 120

Longtime Slashdot reader hackingbear writes: South China Morning Post, citing Chinese state media, reported that an experimental reactor developed in the Gobi Desert by the Chinese Academy of Sciences' Shanghai Institute of Applied Physics has achieved thorium-to-uranium fuel conversion, paving the way for an almost endless supply of nuclear energy. It is the first time in the world that scientists have been able to acquire experimental data on thorium operations from inside a molten salt reactor according to a report by Science and Technology Daily. Thorium is much more abundant and accessible than uranium and has enormous energy potential. One mine tailings site in Inner Mongolia is estimated to hold enough of the element to power China entirely for more than 1,000 years.

At the heart of the breakthrough is a process known as in-core thorium-to-uranium conversion that transforms naturally occurring thorium-232 into uranium-233 -- a fissile isotope capable of sustaining nuclear chain reactions within the reactor itself. Thorium (Th-232) is not itself fissile and so is not directly usable in a thermal neutron reactor. Thorium fuels therefore need a fissile material as a 'driver' so that a chain reaction (and thus supply of surplus neutrons) can be maintained. The only fissile driver options are U-233, U-235 or Pu-239. (None of these are easy to supply.) In the 1960s, the Oak Ridge National Laboratory (USA) designed and built a demonstration MSR using U-233, derived externally from thorium as the main fissile driver.

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China Achieves Thorium-Uranium Conversion Within Molten Salt Reactor

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  • by klipclop ( 6724090 ) on Wednesday November 05, 2025 @02:28AM (#65774338)
    I remember years ago reading that the nuclear power construction companies purposely setup regulatory roadblocks so that the West would be stuck using 1940's ERA reactor designs originally for producing weapons grade uranium. It's sad that this is another breakthrough technology coming out of China due to the west not willing to move away from legacy nuclear power...
    • by Anonymous Coward

      I remember years ago reading that the nuclear power construction companies purposely setup regulatory roadblocks so that the West would be stuck using 1940's ERA reactor designs originally for producing weapons grade uranium. It's sad that this is another breakthrough technology coming out of China due to the west not willing to move away from legacy nuclear power...

      Hold that thought until we see actual operational systems in China. This is a proof of concept with an experimental reactor. Scale may prove to have its own challenges.

      Also hate reading headlines wondering how easily they will turn into hey, whatever happened to endings after a decade of waiting, because some billionaire coal pimp filed a patent infringement claim. When we find this purposely hidden technology is as old as Greed.

      • by HiThere ( 15173 )

        Scale *will* have its own challenges. So will maintenance. This is an "always true". They may well but soluble, but that sure isn't guaranteed.

      • by cusco ( 717999 )

        China is building new-technology nuclear reactors literally as fast as they can select sites and pour concrete. They've issued 30 permits for new plants in the last 3 years (and are exporting 15 more around the world), in spite of the average cost of $0.08/kwh (US cost is $0.18, Ireland is $0.45). This is yet another high tech industry that the West has given up on and allowed a country which a generation ago was clearly in the Third World to take over.

      • Hasn't India been working on this since the 1950s with it's three-stage program? Haven't kept up on how far their FBR program has got because they kept running into delays, but at one point they were supposed to be running in 2022.
    • by AmiMoJo ( 196126 ) on Wednesday November 05, 2025 @05:15AM (#65774488) Homepage Journal

      There have been several experimental thorium based reactors developed in Western countries. They all ended in failure. New problems discovered, very expensive to fix and deal breakers for commercial operation.

      The reason they keep returning to old designs is because they are proven. Developing new reactors is expensive and slow. They are a huge financial risk, because they often don't work and not only is the investment is lost, there is a huge clean up cost too.

      Right now there is also the fact that renewables are much cheaper and rapidly gaining dominance, so even if your wonderful new reactor does work, will anybody want it in 20-30 years time? Maybe... If it provides weapons grade material.

      • Renewables still all come down to not being always available. Which means complex storage solutions, or generation by alternative means. Right now that's mainly natural gas and coal.

        Will people in 20-30 years want power at night in the middle of a large wind storm that requires the wind turbines to be parked? I'd wager so.

        • by AmiMoJo ( 196126 )

          It's fairly easy and cheap to get to 95% renewable power, and use gas for the rest. Offset or capture the gas emissions and you are at net zero, with that energy being incredibly cheap most of the time.

          • Gas takes time and money to get those boilers (steam engines) up and running... What is done, is that hydro is shutdown quicker so that the gas/coal/nuke can continue to run. Hydro is more like a mechanical battery (charged by the rain or a pump;) sadly, your gas actually reduces the hydro and battery usage. If we're talking adaptable grids, there is no practical place for this base load BS the industry argues to prolong their steam engines. The profitable times are during high demand and the losses are

            • Gas takes time and money to get those boilers (steam engines) up and running..

              Not really...relative to the other energy techs, gas is one of the quickest and cheapest to toggle on and off as needed. That's why they're ideal as peakers.

              • not ideal. batteries are ideal. hydro is ideal. Simply using distance grid transport is great too. They are still not great to flip on and off constantly. For short spikes, flywheels are probably better.

                Still, base load power for the grid is a myth; it's not going to be cost effective, it probably isn't already - not too many run those turbines very long.

            • by dryeo ( 100693 )

              Gas turbines spin up very quickly and produce electricity, though maximum output, using the waste heat to boil water is slower to ramp up.

          • by Kokuyo ( 549451 )

            That would be true if you could just scale the gas to this 5% load demand and let it produce 24/7 like that.

            The problem is that we have times where 50 or even 70% of renewable generation cuts out for twenty minutes. You cannot pay for 70% load in gas and you cannot turn it on fast enough to stop a cascade failure from happening.

            Numbers in the hands of quick draws are a dangerous thing. This is a complex problem. Simple solutions to complex problems are always false.

            • by AmiMoJo ( 196126 )

              If 70% of renewables cut out for 20 minutes you would be more concerned with the on going huge natural disaster that probably brought down many of the power lines anyway.

              For hours of low output we have storage.

        • Renewables still all come down to not being always available. Which means complex storage solutions, or generation by alternative means. Right now that's mainly natural gas and coal.

          Will people in 20-30 years want power at night in the middle of a large wind storm that requires the wind turbines to be parked? I'd wager so.

          I have a solar battery system that has had 100 percent uptime since installed years ago. In the meantime, my mains power was off for over a week earlier this year, and a number of days last year. So that storm that knocks out wind will knock out any power source. Regardless energy storage isn't all that complex, given that hydraulic storage is in regular use, and the present electrical grid gets along pretty well via switching power. A cell array, battery array, charge controller, and inverter isn't te

          • For a single home? No, it's not that complex, but can be expensive depending on total needs. Average cost is $15-16,000 USD to start and goes up for more capacity.

            Grid level storage? Much more complex.

            The goal isn't to have 99.99999999% grid uptime. It would be supporting known common events. It's night? You don't have solar? Strong storm? Wind is parked. A foot of snow, and then overcast for the next week with the 8.5 hours of sunlight per day? Much more difficult.

            • by dryeo ( 100693 )

              Strong storms like you describe mean no power for a week, using traditional generating plants, hydro here. Just today there are all kinds of power outages with the current storm.
              Funny enough the last really big storm seen every highway wiped out from flooding, along with the train tracks and all pipelines shutdown. Gas rationing as it was barged in, yet the lights stayed on mostly.

      • by cusco ( 717999 )

        deal breakers for commercial operation.

        And that's the issue, isn't it? If it doesn't make money for someone within five years than it's no longer considered worth exploring since those executives will have moved to looting some other company by then. Once upon a time ATT could fund bleeding edge work in basic science without concerning itself whether Bell Labs would return a profit within the current CEO's term, and they were the world's technology leader in many fields. Those days have gone, we've passed the baton to China and India, who hav

        • by AmiMoJo ( 196126 )

          Investors are willing to throw money at nuclear fusion, but that's because it's actually reasonably clean and safe.

          Nuclear fission for energy production has been going since the 1950s, and 7 decades later it's still not really commercially viable or a safe investment. People keep claiming to have the next miracle solution for it, but I think most experts can see that none of them are very likely to make any real difference.

          Most of the basic science has been done here, it's really about figuring out how to h

          • by cusco ( 717999 )

            "it's still not really commercially viable or a safe investment" in the United States or EU.

            FTFY. We're not the whole world.

            • Spot on. (An EU guy)

            • by AmiMoJo ( 196126 )

              It's often worse elsewhere. They would need to develop a whole nuclear industry, and convince their neighbours that they aren't going to produce weapons.

              • by cusco ( 717999 )

                Not really, most of the countries which have nuclear power plants don't refine their own fuel. They buy a power station from (now China, formerly the US/EU) and then fuel from (now Russia, formerly the US/EU), and just send techs to be trained in its operation. As far as the power grid is concerned it's just another power station, it doesn't care where the electrons come from.

                This is why China has been able to sell 15 nuclear power plants just in the last few years to other BRICS+ countries around the wor

                • by AmiMoJo ( 196126 )

                  They need a nuclear industry for more than just refining fuel. They need to be able to run those plants, handle the waste, have regulatory oversight. Deal with the IAEA. Can't just pay China to come build a plant, set it and forget it.

                  They may well come to regret buying those plants, when they discover that they are dependent on China to keep them operating.

                  • by cusco ( 717999 )

                    Of course China and Russia are going to provide support, and they'll probably regret it a lot less than those countries which bought plants from the US!

          • by XXongo ( 3986865 )

            Investors are willing to throw money at nuclear fusion, but that's because it's actually reasonably clean and safe.

            Good lord, that's what they like to say, but nowhere near true. The only fusion reaction likely to be achieved soon is D-T, and that sprays neutrons out like a firehose. Everything nearby gets neutron activated. The reactor itself has only a finite lifetime before it's too radioactive to use.

    • Was it the power companies or the DoE and military? The military needs weapons-grade material, so the DoE made sure we built reactors that supplied it.
      • It's never one thing, it's never one group. It's always a cartel or conspiracy, there are always multiple goals being pursued, usually by individual participants let alone the aggregate of the groups.

  • Working out the waste and other problems is something they can now work on. We can't.
    • by HiThere ( 15173 )

      Waste from a molten salt reactor should be fairly stable. Put it in the center of a glass brick and use it as a low level heat source. (Actually, that's what I think they ought to do with most reactor waste except the stuff that's too hot for glass to hold. And you might need a couple of barriers within the glass. Glass would stop alpha and beta cold, but some gamma might need a lead foil screen.)

      Yes, there's a paper saying that given enough centuries the waste will slowly leach out. But the level of t

      • Re: (Score:2, Insightful)

        by cusco ( 717999 )

        Or you could bury it at the bottom of an oceanic trench, where "given enough centuries" it will be subducted into Earth's mantle.

        • Or you could bury it at the bottom of an oceanic trench, where "given enough centuries" it will be subducted into Earth's mantle.

          This has been studied and it's not that simple. First you have to get it there, then you have to ensure it doesn't break open and spread before it gets subducted. I had the same idea, it just turned out to not be a good one.

          • by cusco ( 717999 )

            Glassification works for the majority of the waste, and if a glass block "breaks open" nothing spills out. While mining at extreme depths is problematic the opposite, burying something, should not pose much difficulty if it's done robotically. We've been exploring the ocean trenches for a couple of decades now with robots, and the advances in the technology the last few years is amazing. Life in sediment at the benthic depths is mostly limited to the upper few meters because of the lack of gas exchange,

            • Glassification works for the majority of the waste, and if a glass block "breaks open" nothing spills out.

              Glassification is viable in every way but financially. It's incompatible with capitalism.

        • by spitzak ( 4019 )

          I think your idea of how fast subduction happens is a little off by some orders of magnitude.

          However encasing it in something that won't leak (like glass) and dumping it in a very deep and dead part of the ocean is plausible and may be the best idea we have. There is no need to aim for the subduction fault, that makes no difference.

        • by HiThere ( 15173 )

          In addition to the other objection, "low level heat" is a useful commodity. Why not use it rather than throwing it away.

  • by Qbertino ( 265505 ) <moiraNO@SPAMmodparlor.com> on Wednesday November 05, 2025 @04:32AM (#65774446)

    ... up with a method to convert radiation to electricity directly, we'd be ready to back to nuclear power.
    Until then it remains a dead end.

    Nuclear fuel or power isn't the problem. Nuclear Fission steam power and nuclear waste is.

  • We should hear from him. He must be having multiple Os over this.

  • .. we are saved !! Long live beautiful beautiful China,!!!
  • by packrat0x ( 798359 ) on Wednesday November 05, 2025 @07:34AM (#65774612)

    From https://world-nuclear.org/info... [world-nuclear.org]

    "The TMSR-LF (liquid fuel) stream claims full closed Th-U fuel cycle with breeding of U-233 and much better sustainability but greater technical difficulty. SINAP aims for a 10 MWt pilot plant by 2030 and a 100 MWt demonstration plant by 2040."
    The fuel is both corrosive (F) and Toxic (Be). Still better than *radioactive*.

    "A TMSR-LF fast reactor optimized for burning minor actinides [from LWRs] is to follow"
    This design minimizes nuclear waste, similar to a breeder reactor.

    "SINAP sees molten salt fuel being superior to the TRISO fuel in effectively unlimited burn-up, less waste, and lower fabricating cost, but achieving lower temperatures (600ÂC+) than the TRISO fuel reactors (1200ÂC+). Near-term goals include preparing nuclear-grade ThF4 and ThO2 and testing them in a MSR. The US Department of Energy (especially Oak Ridge NL) is collaborating with the Academy on the program, which had a start-up budget of $350 million."
    We already have proof of concept in Tennessee.

    "However, the primary reason that American researchers and the China Academy of Sciences/ SINAP are working on solid fuel, salt-cooled reactor technology is that it is a realistic first step. The technical difficulty of using molten salts is significantly lower when they do not have the very high activity levels associated with them bearing the dissolved fuels and wastes. The experience gained with component design, operation, and maintenance with clean salts makes it much easier then to move on and consider the use of liquid fuels, while gaining several key advantages from the ability to operate reactors at low pressure and deliver higher temperatures."
    Solid fuel is practice reactor.

    "Accelerator-driven reactors: A number of groups have investigated how a thorium-fuelled accelerator-driven reactor (ADS) may work and appear. Perhaps most notable is the âADTRâ(TM) design patented by a UK group. This reactor operates very close to criticality and therefore requires a relatively small proton beam to drive the spallation neutron source. Earlier proposals for ADS reactors required high-energy and high-current proton beams which are energy-intensive to produce, and for which operational reliability is a problem."
    So, no more U233 or U235 required to to start the MSR?

    • by AmiMoJo ( 196126 )

      Small demonstration plant by 2040, so useless for addressing climate change. Even if the demonstration plant works, commercial scale will still be decades away.

      Nothing about them being able to use less enriched fuel or make it impossible to produce weapons grade material. The fuel being illegal has been an issue for some projects.

      The thing that usually kills MSRs is the corrosive nature of the salt.

      • Small demonstration plant by 2040, so useless for addressing climate change.

        If you are around in 2040 you will still be complaining about continued fossil fuel use and that nuclear takes too long.

      • Small demonstration plant by 2040, so useless for addressing climate change.

        Climate change is a long term problem. We will still need energy sources in 2040.

        Nothing about them being able to use less enriched fuel or make it impossible to produce weapons grade material.

        That's one of the selling points of thorium cycles, that it's more difficult to use to make weapons grade materials. Note "more difficult" may not mean "completely impossible."

        The fuel being illegal has been an issue for some projects.

        That would be highly-enriched uranium ("HEU"), not thorium

    • by 602 ( 652745 )
      FYI Abilene Christian University is currently building a small research molten salt reactor, although not with thorium I think.
  • I thought that adding to the nucleus (232 -> 233) requires fusion. Can someone please explain?
    • At the heart of the breakthrough is a process known as in-core thorium-to-uranium conversion that transforms naturally occurring thorium-232 into uranium-233 – a fissile isotope capable of sustaining nuclear chain reactions.

      This transformation occurs through a precise sequence of nuclear reactions. The thorium-232 absorbs a neutron to become thorium-233, which decays into protactinium-233 and then further decays into the final product – a powerful nuclear fuel.
    • I thought that adding to the nucleus (232 -> 233) requires fusion. Can someone please explain?

      Neutron capture is not usually considered fusion.

      • But how do you go from Thorium to Uranium without fusion?
        • But how do you go from Thorium to Uranium without fusion?

          Thorium 232 captures a neutron, turning into Thorium 233. Thorium 233 decays to Uranium 233 by successive beta decays.

  • by mrspoonsi ( 2955715 ) on Wednesday November 05, 2025 @10:30AM (#65774976)
    Wait until they have it running for 10 years and see what that salt has done to the internals. Like dipping something metal in sea water for 10 years, except access is limited due to radioactivity. (used to work in Nuclear reactors and corrosion, that was standard high pressure reactors).
  • The Fort St. Vrain commercial reactor in Colorado was gas-cooled and ran on a Th232-to-U233 fuel cycle. Fissile U235 was used to get started, but almost all of the energy output was from fissioning U233 produced in the reactor.
  • was going to have 5 Thorium reactors on line this year.... Guess that didn't work out so well.

  • Another rich target missed...

  • In the near past, we Westerners would take any claims of success from China with a grain of salt. It's probably vaporware, etc etc.
    Not so much now. Meanwhile, the US is making coal great again, handing out new drilling leases, powering data centers with methane from the fracking fields.

The unfacts, did we have them, are too imprecisely few to warrant our certitude.

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