Part 2 of 2 Parts (Please read Part 1 first)
     The main political problem that causes concern for the adoption of MSRs is the fact that they are perceived pose a nuclear weapons proliferation problem. Non-proliferation experts state that as soon as the cladding of a nuclear fuel rod is cut open, it poses a proliferation danger. Obviously, because the fuel in a MSR is already exposed in a vat of molten salt, it is already part way to a useful material for making nuclear bombs.
1. Protactinium-233 decays to pure, weapons-grade U-233 – Many thorium-cycle MSRs have to capture protactinium as it is produced, remove it from the reactor while it decays to U-233 and then mix it back in with the molten salt. This is necessary because Pa-233 absorbs so many neutrons that it prevents the maintenance of a fuel breeding cycle. The problem with this process is that U-233 is pure weapons grade uranium which could be used to make a bomb. The U-233 is usually mixed with zirconium but the zirconium is easy to remove. Most common power reactors do not require such a proliferative stage in their fuel cycle. In addition, many types of MSRs do not carry out such a process. Liquid fluoride thorium reactors (LFTR) do require this process. This means that anyone who is operating a LFTR could be producing nuclear bombs. There are many suggestions of how to mitigate this problem such as deliberately using U-232 to contaminate and denature the U-233 would only serve to prevent diversion by criminal or terrorist third parties. However, for the owners of a LFTR nuclear plant, it would be easy to deal with most of the fixes suggested.
2. Inventory tracking is difficult – Because a lot of the materials in the fuel will plate out in the fuel vat and the chemical plant, it can be very difficult to keep precise records of all of the actinides. The International Atomic Energy Agency (IAEA) requires the installation of safeguards in reactors to ensure that all the actinides are accounted for. This is done to prevent proliferation. However, it can be difficult for the IAEA to separate plate out losses from proliferation diversion.

     There are a few other problems but they will probably have practical solutions.
1. Unknown waste form – Since MSRs are a new technology, it is not yet clear exactly what the waste from MSRs will look like. The molten salt is not stable enough to be put in a repository. There will have to work on the development of a stable waste form for the molten salt.
2. Electrical heaters are required to stay liquid – During a long power outage, the colder parts of the heat transfer loop in the MSR could solidify. This could result in temperatures to rise in the core. This could be a problem.

     In order for MSRs to breed in a thermal spectrum, if there is lithium in the mixture, it must be enriched to very pure Li-7. Li-6 is a very strong neutron poison which becomes tritium. FliBe is a molten salt of beryllium fluoride and lithium fluoride. FliBe is a controlled substance and it has some weapons applications. It is also a very dangerous materials when inhaled. In chloride salts, the chloride must be enriched to pure Cl-37. Cl-35 is a strong neutron poison which will prevent nuclear fission. The activation product of Cl-36 is long-lived, water soluble, and a hard beta particle emitter which complicates waste disposal. These enrichments increase the cost and complexity of the MSR fuel cycles.
     There are more specific problems with each specific type of MSRs in addition to the problems mentioned above. MSRs are underdeveloped and will require a great deal more research, especially with respect to corrosion issues before they will be ready to be added to the world fleet of commercial nuclear fission power reactors. They may ultimately be viable sources of electricity but that remains to be seen.

Ambient office = 100 nanosieverts per hour

Ambient outside = 108 nanosieverts per hour

Soil exposed to rain water = 106 nanosieverts per hour

Jalapeno pepper from Central Market = 133 nanosieverts per hour

Tap water = 97 nanosieverts per hour

Filter water = 80 nanosieverts per hour

Part 1 of 2 Parts
     I have written about molten salt reactors (MSRs) in the past. In a molten salt reactor, the fuel is mixed with a molten salt. The mixture not only acts as the fuel but also acts as the coolant. There are supporters of this technology who point out that tit will be much safer because MSRs cannot possibly melt down. They can be refueled without shutting down. Fuel is just dumped into the vat to melt into the mix and there is no needed for creating fuel rods and all the machinery they require. MSRs can run at higher temperatures which should make them more efficient. However, they do have problems and challenges which help explain why they have not been adopted for commercial power production even though they have been researched since 1964.
     The main problem with MSRs is that the radioactive fission products in the fuel can easily escape. The fuel is not in tubes covered with cladding but is just sitting in a big vat mixed with a molten salt. The vat can be enclosed in multiple layers of containment but it is still difficult to track and trap all the radioactive materials. In addition to the radioactive fission products and actinides in the vat, there are also chemicals which can corrode the containment vessel.
1. Material degradation – The molten salt fuel in the vat contains about half the elements in the periodic table. That means that all of these elements are in contact with the containment vessel and this raises serious concerns about corrosion. Noble metals include rhenium, ruthenium, rhodium, palladium, silver, osmium, iridium, platinum, and gold. They will naturally plate out on cold metal. In a nuclear power reactor, a heat exchanger will be the coldest metal available. This means that the heat transfer surfaces will need periodic replacement. Inside the Molten-Salt Reactor Experiment at the Idaho National Laboratory, tellurium caused the Hastelloy-N material to crack. This was solved by chemically treating the fuel, but the same type of problem could plague commercial reactors with long life-spans.
2. Tritium production – If lithium is one of the ingredients for the fuel, tritium will be produced. Tritium is the radioactive isotope of hydrogen. It is extremely mobile and can easily move thru metals. At the Oak Ridge National Laboratory, they used a special sodium fluoroborate intermediate salt to capture most of the tritium produced but a great deal still escaped into the environment. 
3. Complex Chemical plant – It will be fairly easy to remove some of the fission products from the fuel. However, more serious fission product (or actinides) separation will require complex processes such as the liquid bismuth reduction process, volatilization or electroplating. These have been exhaustively researched but they are complex enough to be a challenge.
4. Remote Maintenance – The chemical plants associated with MSRs will need periodic maintenance but all of the equipment at the MSR will be highly radioactive. Remote maintenance is necessary and will be expensive. If a graphite moderator is used, it will be expensive to replace it with remote manipulation equipment.
Please read Part 2 next

Ambient office = 93 nanosieverts per hour

Ambient outside = 126 nanosieverts per hour

Soil exposed to rain water = 125 nanosieverts per hour

Parsely from Central Market =93 nanosieverts per hour

Tap water = 80 nanosieverts per hour

Filter water = 66 nanosieverts per hour

      The National Nuclear Laboratory (NNL) is a U.K. government owned and operated nuclear fission services technology provider covering the whole nuclear fuel cycle. They have just launched their strategic plan which they call “This is NNL”. They are working towards legally binding targets in the U.K. to achieve net-zero greenhouse gas emissions by 2050. More than one hundred and twenty other countries are working towards the same goal.
     The NNL will focus on four strategic areas of national importance:
1. Clean Energy – “A thriving nuclear power sector is an essential component of the UK’s path to net zero.”
2. Environmental Restoration – “For 65 years, the UK’s nuclear power stations have generated electricity, successfully providing nearly a fifth of its current overall power needs and two-fifths of its clean electricity.”
3. Health and Nuclear Medicine – “Each year, thousands of National Health Service patients benefit from the advances of nuclear medicine in their treatment.”
4. Security and Non-proliferation – “It is clear that nuclear science holds the keys to advancing many areas of our lives and can help governments and industry to create a better planet for us all.”
     In attacking these four areas, NNL says that it will also be supporting the creation of high-skilled, high-paid jobs predominantly in the North West of England because all four of the national laboratories involved in NNL are located in that area.
     Paul Howarth is the NNL Chief Executive Officer. He said, “Without nuclear, the UK will not meet this target on time. And without NNL’s work, the UK nuclear sector cannot deliver what is required. Whether it is accelerating a UK demonstration program for Advanced Modular Reactors or delivering our first indigenous supply of medical radioisotopes since the 1960s, NNL will be at the forefront of game-changing advances that will help to transform the environment and people’s lives, now and into the future.”
     The published materials on “This is NNL” includes an interview with Fiona Rayment who is the Chief Science and Technology Officer of NNL. She said, “Our Focus Areas make perfect sense because they all have three qualities in common: they are all greatly needed by the UK, they are all areas we are working on now, and they all are areas where we have the capability – by which I mean the infrastructure and skills – to expand and work with the whole of the nuclear sector to successfully contribute.”
      Rayment also said, “Collaboration is key in the nuclear sector, because no single area of expertise resides in just one organization. We would like to be in a situation where we operate a user facility for our infrastructure, so that academia, other national labs and the entirety of the supply chain can all access it. It will be the nuclear industry that goes on to sell and utilize reactor technology but our role is to underpin what the technology does, so that it can be successfully deployed within the commercial marketplace.”
     Anne-Marie Trevelyan is the Energy Minister of the U.K. In the same publication, she says that new and advanced nuclear technologies are key parts of the government’s Ten Point Plan for a Green Industrial Revolution because they believe that nuclear power provides a reliable source of low-carbon electricity. “The National Nuclear Laboratory is at the forefront of pioneering innovation and remains a world leader in nuclear research and development. I am delighted that NNL is playing a critical role in developing next-generation nuclear fuels and fuel cycles, helping us build back greener and eliminating the UK’s contribution to climate change.”

Ambient office = 121 nanosieverts per hour

Ambient outside = 143 nanosieverts per hour

Soil exposed to rain water = 147 nanosieverts per hour

Red bell pepper from Central Market = 112 nanosieverts per hour

Tap water = 140 nanosieverts per hour

Filter water = 126 nanosieverts per hour