Molten Salt Reactor: Rethinking the fuel cycle in the future of nuclear power?

By Fouad Sabry

What Is Molten Salt Reactor

A kind of nuclear fission reactor known as a molten salt reactor, or MSR for short, is one in which the main nuclear reactor coolant and/or the fuel is a mixture of molten salt. There have only ever been two MSRs in operation, and both of them were research reactors in the United States. The Molten-Salt Reactor Experiment of the 1960s aimed to prove the concept of a nuclear power plant that implements a thorium fuel cycle in a breeder reactor, whereas the Aircraft Reactor Experiment of the 1950s was primarily motivated by the compact size that the technique offers. The Aircraft Reactor Experiment was conducted in the 1950s. Increased research into Generation IV reactor designs started to reinvigorate interest in the technology, and as of September 2021, China was on the brink of beginning its TMSR-LF1 thorium MSR. This interest was sparked by the fact that numerous countries had projects using the technology.

How You Will Benefit

(I) Insights, and validations about the following topics:

Chapter 1: Molten salt reactor

Chapter 2: Nuclear reactor

Chapter 3: Pebble-bed reactor

Chapter 4: Breeder reactor

Chapter 5: Fast-neutron reactor

Chapter 6: Void coefficient

Chapter 7: Passive nuclear safety

Chapter 8: Nuclear fuel

Chapter 9: Generation IV reactor

Chapter 10: High-temperature gas reactor

Chapter 11: Thorium fuel cycle

Chapter 12: Alvin M. Weinberg

Chapter 13: Molten-Salt Reactor Experiment

Chapter 14: Liquid fluoride thorium reactor

Chapter 15: FLiBe

Chapter 16: Thorium-based nuclear power

Chapter 17: Integral Molten Salt Reactor

Chapter 18: ThorCon nuclear reactor

Chapter 19: Dual fluid reactor

Chapter 20: Stable salt reactor

Chapter 21: TMSR-LF1

(II) Answering the public top questions about molten salt reactor.

(III) Real world examples for the usage of molten salt reactor in many fields.

(IV) 17 appendices to explain, briefly, 266 emerging technologies in each industry to have 360-degree full understanding of molten salt reactor' technologies.

Who This Book Is For

Professionals, undergraduate and graduate students, enthusiasts, hobbyists, and those who want to go beyond basic knowledge or information for any kind of molten salt reactor.

• Language: English
• Publisher: One Billion Knowledgeable
• Release date: Oct 15, 2022

Book preview

Copyright

Molten Salt Reactor Copyright © 2022 by Fouad Sabry. All Rights Reserved.

All rights reserved. No part of this book may be reproduced in any form or by any electronic or mechanical means including information storage and retrieval systems, without permission in writing from the author. The only exception is by a reviewer, who may quote short excerpts in a review.

Cover designed by Fouad Sabry.

This book is a work of fiction. Names, characters, places, and incidents either are products of the author’s imagination or are used fictitiously. Any resemblance to actual persons, living or dead, events, or locales is entirely coincidental.

Bonus

You can send an email to [e-mail] with the subject line Molten Salt Reactor: Rethinking the fuel cycle in the future of nuclear power?, and you will receive an email which contains the first few chapters of this book.

Fouad Sabry

Visit 1BK website at

www.1BKOfficial.org

Preface

Why did I write this book?

The story of writing this book started on 1989, when I was a student in the Secondary School of Advanced Students.

It is remarkably like the STEM (Science, Technology, Engineering, and Mathematics) Schools, which are now available in many advanced countries.

STEM is a curriculum based on the idea of educating students in four specific disciplines — science, technology, engineering, and mathematics — in an interdisciplinary and applied approach. This term is typically used to address an education policy or a curriculum choice in schools. It has implications for workforce development, national security concerns and immigration policy.

There was a weekly class in the library, where each student is free to choose any book and read for 1 hour. The objective of the class is to encourage the students to read subjects other than the educational curriculum.

In the library, while I was looking at the books on the shelves, I noticed huge books, total of 5,000 pages in 5 parts. The books name is The Encyclopedia of Technology, which describes everything around us, from absolute zero to semiconductors, almost every technology, at that time, was explained with colorful illustrations and simple words. I started to read the encyclopedia, and of course, I was not able to finish it in the 1-hour weekly class.

So, I convinced my father to buy the encyclopedia. My father bought all the technology tools for me in the beginning of my life, the first computer and the first technology encyclopedia, and both have a great impact on myself and my career.

I have finished the entire encyclopedia in the same summer vacation of this year, and then I started to see how the universe works and to how to apply that knowledge to everyday problems.

My passion to the technology started mor than 30 years ago and still the journey goes on.

This book is part of The Encyclopedia of Emerging Technologies which is my attempt to give the readers the same amazing experience I had when I was in high school, but instead of 20th century technologies, I am more interested in the 21st century emerging technologies, applications, and industry solutions.

The Encyclopedia of Emerging Technologies will consist of 365 books, each book will be focused on one single emerging technology. You can read the list of emerging technologies and their categorization by industry in the part of Coming Soon, at the end of the book.

365 books to give the readers the chance to increase their knowledge on one single emerging technology every day within the course of one year period.

Introduction

How did I write this book?

In every book of The Encyclopedia of Emerging Technologies, I am trying to get instant, raw search insights, direct from the minds of the people, trying to answer their questions about the emerging technology.

There are 3 billion Google searches every day, and 20% of those have never been seen before. They are like a direct line to the people thoughts.

Sometimes that’s ‘How do I remove paper jam’. Other times, it is the wrenching fears and secret hankerings they would only ever dare share with Google.

In my pursuit to discover an untapped goldmine of content ideas about Molten Salt Reactor, I use many tools to listen into autocomplete data from search engines like Google, then quickly cranks out every useful phrase and question, the people are asking around the keyword Molten Salt Reactor.

It is a goldmine of people insight, I can use to create fresh, ultra-useful content, products, and services. The kind people, like you, really want.

People searches are the most important dataset ever collected on the human psyche. Therefore, this book is a live product, and constantly updated by more and more answers for new questions about Molten Salt Reactor, asked by people, just like you and me, wondering about this new emerging technology and would like to know more about it.

The approach for writing this book is to get a deeper level of understanding of how people search around Molten Salt Reactor, revealing questions and queries which I would not necessarily think off the top of my head, and answering these questions in super easy and digestible words, and to navigate the book around in a straightforward way.

So, when it comes to writing this book, I have ensured that it is as optimized and targeted as possible. This book purpose is helping the people to further understand and grow their knowledge about Molten Salt Reactor. I am trying to answer people’s questions as closely as possible and showing a lot more.

It is a fantastic, and beautiful way to explore questions and problems that the people have and answer them directly, and add insight, validation, and creativity to the content of the book – even pitches and proposals. The book uncovers rich, less crowded, and sometimes surprising areas of research demand I would not otherwise reach. There is no doubt that, it is expected to increase the knowledge of the potential readers’ minds, after reading the book using this approach.

I have applied a unique approach to make the content of this book always fresh. This approach depends on listening to the people minds, by using the search listening tools. This approach helped me to:

Meet the readers exactly where they are, so I can create relevant content that strikes a chord and drives more understanding to the topic.

Keep my finger firmly on the pulse, so I can get updates when people talk about this emerging technology in new ways, and monitor trends over time.

Uncover hidden treasures of questions need answers about the emerging technology to discover unexpected insights and hidden niches that boost the relevancy of the content and give it a winning edge.

The building block for writing this book include the following:

(1) I have stopped wasting the time on gutfeel and guesswork about the content wanted by the readers, filled the book content with what the people need and said goodbye to the endless content ideas based on speculations.

(2) I have made solid decisions, and taken fewer risks, to get front row seats to what people want to read and want to know — in real time — and use search data to make bold decisions, about which topics to include and which topics to exclude.

(3) I have streamlined my content production to identify content ideas without manually having to sift through individual opinions to save days and even weeks of time.

It is wonderful to help the people to increase their knowledge in a straightforward way by just answering their questions.

I think the approach of writing of this book is unique as it collates, and tracks the important questions being asked by the readers on search engines.

Acknowledgments

Writing a book is harder than I thought and more rewarding than I could have ever imagined. None of this would have been possible without the work completed by prestigious researchers, and I would like to acknowledge their efforts to increase the knowledge of the public about this emerging technology.

Dedication

To the enlightened, the ones who see things differently, and want the world to be better -- they are not fond of the status quo or the existing state. You can disagree with them too much, and you can argue with them even more, but you cannot ignore them, and you cannot underestimate them, because they always change things... they push the human race forward, and while some may see them as the crazy ones or amateur, others see genius and innovators, because the ones who are enlightened enough to think that they can change the world, are the ones who do, and lead the people to the enlightenment.

Epigraph

A kind of nuclear fission reactor known as a molten salt reactor, or MSR for short, is one in which the main nuclear reactor coolant and/or the fuel is a mixture of molten salt. There have only ever been two MSRs in operation, and both of them were research reactors in the United States. The Molten-Salt Reactor Experiment of the 1960s aimed to prove the concept of a nuclear power plant that implements a thorium fuel cycle in a breeder reactor, whereas the Aircraft Reactor Experiment of the 1950s was primarily motivated by the compact size that the technique offers. The Aircraft Reactor Experiment was conducted in the 1950s. Increased research into Generation IV reactor designs started to reinvigorate interest in the technology, and as of September 2021, China was on the brink of beginning its TMSR-LF1 thorium MSR. This interest was sparked by the fact that numerous countries had projects using the technology.

Table of Contents

Copyright

Bonus

Preface

Introduction

Acknowledgments

Dedication

Epigraph

Table of Contents

Chapter 6: Molten salt reactor

Chapter 2: Nuclear reactor

Chapter 3: Breeder reactor

Chapter 4: Breeder reactor

Chapter 5: Fast-neutron reactor

Chapter 6: Passive nuclear safety

Chapter 7: Nuclear fuel

Chapter 7: Nuclear fuel

Chapter 9: Generation IV reactor

Chapter 9: Supercritical water reactor

Chapter 11: Lead-cooled fast reactor

Chapter 12: Alvin M. Weinberg

Chapter 13: Molten-Salt Reactor Experiment

Chapter 14: Liquid fluoride thorium reactor

Chapter 15: Fuji Molten Salt Reactor

Chapter 16: List of small modular reactor designs

Chapter 17: Integral Molten Salt Reactor

Chapter 18: Thorium-based nuclear power

Chapter 19: Integral Molten Salt Reactor

Chapter 20: Transatomic Power

Chapter 21: Stable salt reactor

Epilogue

About the Author

Coming Soon

Appendices: Emerging Technologies in Each Industry

Chapter 6: Molten salt reactor

A kind of nuclear fission reactor known as a molten salt reactor, or MSR for short, is one in which the main nuclear reactor coolant and/or the fuel is a mixture of molten salt. There have only ever been two MSRs in operation, and both of them were research reactors in the United States. The Molten-Salt Reactor Experiment of the 1960s aimed to prove the concept of a nuclear power plant that implements a thorium fuel cycle in a breeder reactor, whereas the Aircraft Reactor Experiment of the 1950s was primarily motivated by the compact size that the technique offers. The Aircraft Reactor Experiment was conducted in the 1950s. Increased research on Generation IV reactor designs started to reinvigorate interest in the technology, with various countries having projects, and as of September 2021, China is on the brink of beginning its TMSR-LF1 thorium MSR reactor. [Citation needed].

MSRs are thought to be safer than conventional reactors due to the fact that they operate with fuel that is already in a molten state. Additionally, in the event of an emergency, the fuel mixture is designed to drain from the core and into a containment vessel, where it will solidify in fuel drain tanks. This eliminates the possibility of traditional (solid-fuel) reactors experiencing an uncontrolled nuclear meltdown as well as the related hydrogen explosions, as were seen during the nuclear tragedy at Fukushima. instead of raising the pressure within the fuel tubes during the life of the fuel, as is done in traditional solid-fuelled reactors, this kind of reactor maintains a constant pressure throughout. MSRs also have the ability to be refueled while they are functioning, which is effectively the same thing as online nuclear reprocessing. Conventional reactors, on the other hand, have to be shut down in order to be refueled (Heavy water reactors like the CANDU or the Atucha-class PHWRs being a notable exception).

A further key characteristic of MSRs is operating temperatures of around 700 °C (1,292 °F), significantly higher than traditional LWRs at around 300 °C (572 °F), offering a higher level of efficiency in the production of electricity, the potential of facilities that store energy for the grid, economical hydrogen production, and, in a few instances, options for reducing process heat.

The corrosivity of hot salts and the changing chemical composition of the salt as it is transmuted by the neutron flux in the reactor core are both relevant difficulties that must be addressed throughout the design process.

MSRs provide a multitude of benefits that are incomparable to those provided by conventional nuclear power reactors; but, for historical reasons, they have not been implemented.

In comparison to conventional reactors, MSRs, particularly those in which the fuel is dissolved in the salt, have a number of distinctive characteristics. The pressure within a reactor core could be rather low, yet the temperature might be quite high. In this regard, an MSR is more analogous to a light water cooled reactor that uses liquid metal for cooling than it is to a normal light water reactor. In contrast to the once-through fuel that is used in the majority of the United States' nuclear power plants at the present time, MSRs are often conceived of as breeding reactors equipped with closed fuel cycles.

For the purpose of limiting reactivity excursions, safety concepts depend on a temperature coefficient of reactivity that is negative and on a significant probable temperature increase. It is possible to install a second container that is passively cooled underneath the reactor as an alternate technique for shutting down the reactor. In the event that there is a malfunction, as well as for the purposes of routine maintenance, the fuel is drained from the reactor. The nuclear chain reaction is halted, and this also functions as a secondary cooling mechanism. For some very secure subcritical experimental designs, neutron-producing accelerators have been suggested as a solution.

MSRs have numerous potential benefits over the light water reactors that are already in use:

The removal of heat from the decay process is accomplished passively in MSRs, just as it is in all low-pressure reactor designs. Because the fuel and the coolant are the same fluid in certain designs, removing the coolant also removes the reactor's fuel. This is analogous to how removing the moderator in a LWR also removes the coolant in that design. In contrast to steam, fluoride salts have a difficult time dissolving in water and do not produce hydrogen that may be burned. Molten salts, in contrast to steel and solid uranium oxide, are not harmed by the neutron bombardment that occurs in the reactor core; yet, the reactor vessel still is.

Because a low-pressure MSR does not have the high-pressure radioactive steam that a BWR does, it does not experience leaks of radioactive steam and cooling water and does not require the costly containment, steel core vessel, piping, and safety equipment that is required to contain radioactive steam. The vast majority of MSR designs, on the other hand, provide for fluid carrying radioactive fission products to be in direct contact with pumps and heat exchangers.

Because MSRs are able to function with slow neutrons, there is a possibility that they will make closed nuclear fuel cycles more cost-effective. Any reactor that completes the nuclear fuel cycle and so decreases environmental consequences, provided that the plan is carried out in its whole, includes: Through a process of chemical separation, long-lived actinides are converted back into reactor fuel. The majority of the wastes that are released are fission products, often known as nuclear ashes, which have shorter half-lives. Because of this, the amount of time required for geologic containment is reduced from the tens of thousands of years required by spent nuclear fuel from a light-water reactor to only 300 years. Additionally, it allows for the use of alternative nuclear fuels like thorium.

Pyroprocessing might be used on the liquid phase of the fuel in order to extract fission products, also known as nuclear ashes, from actinide fuels. This may offer benefits over the more traditional method of reprocessing, despite the fact that significant development is still required.

The manufacturing of fuel rods is not necessary (replaced with fuel salt synthesis).

Some designs are compatible with the fast neutron spectrum, which may burn troublesome transuranic materials from standard light-water nuclear reactors, such as Pu240, Pu241, and higher (reactor grade plutonium).

In less than one minute, an MSR may respond to changes in the load (unlike traditional solid-fuel nuclear power plants that suffer from xenon poisoning).

Molten salt reactors are able to operate at high temperatures, which results in an increased level of thermal efficiency. This results in a reduction in size, costs, and affects on the environment.

MSRs have the potential to provide a high specific power, which refers to a high power at a low mass, as shown by ARE.

Because of its potential for a favorable neutron economy, the MSR is an appealing option for the neutron-deficient thorium fuel cycle.

Comparatively little progress when compared to the majority of Gen IV designs

In systems that use circulating fuel salt, radionuclides that are dissolved in the fuel come into touch with significant pieces of equipment like as pumps and heat exchangers, which would likely need maintenance to be performed remotely and might be costly.

For certain MSRs, on-site chemical processing is required in order to control core mixture and get rid of fission products.

Required modifications to regulations in order to accommodate significantly differing aspects of design

Nickel-based alloys are used in the construction of certain MSR designs in order to contain the molten salt.

Alloys based on nickel and iron are prone to embrittlement under high neutron flux.: 83

Corrosion risk.

Molten salts need vigilant monitoring of their redox state in order to mitigate the danger of corrosion.

This presents a unique set of challenges for systems that use circulating fuel salt, in which a complicated mixture of fissile and fertile isotopes, together with their respective products of fission, transmutation, and decay, is being pumped through the reactor.

Designs that use static fuel salt take use of the modularization of the issue. The fuel salt is stored inside fuel pins, which are replaced on a regular basis, mostly due to neutron irradiation damage, is a fundamental component of the operational concept; while the chemical make-up of the coolant salt is more straightforward, and, under suitable redox state control, does not put the fuel pins or the reactor vessel at danger of corrosion in any way.

(In reference to the control of redox states), Please refer to the descriptions provided for the fuel and coolant salts used in the stable salt reactor.

The MSRs that were created at ORNL in the 1960s could only be used in a risk-free manner for a limited amount of time, and operated at only about 650 °C.

Potential corrosion risks include dissolution of chromium by liquid fluoride thorium salts at >700 °C, thereby threatening stainless steel components.

Other typical alloying agents, such as cobalt and nickel, are susceptible to transformation by neutron radiation, shortening lifespan.

In the event that lithium salts (such as.

FLiBe), It is to one's advantage, if expensive, to make use of 7Li in order to cut down on tritium production (tritium has the ability to seep into stainless steels), cause embrittlement, and flee towards the surrounding surroundings).

Hastelloy N was created by ORNL in order to assist in addressing these challenges, in addition, there is work being done to get additional types of structural steel approved for use in reactors (316H),, 800H, inco 617).

Some MSR designs might be altered to create a breeder reactor that is able to generate nuclear material that is suitable for use in weapons.

Both the MSRE and the aircraft nuclear reactors employed enrichment levels that were so high that they were dangerously close to those used in nuclear bombs. These levels would violate the law under the vast majority of contemporary regulatory systems that are in place for power facilities. The vast majority of contemporary designs sidestep this problem.

The core lifespan of an MSR that makes use of moderated thermal neutrons may be shortened as a result of neutron damage to solid moderator materials. For instance, the MSRE was constructed with extremely loose tolerances for its graphite moderator sticks so that neutron damage may vary their size without causing any damage to the moderator sticks themselves. Because graphite changes size when it is blasted with neutrons, it is not possible to employ graphite piping in two fluid MSR designs. Graphite pipes would split and leak if they were used in these designs. Because of the need to prevent moderation, an MSR that uses fast neutrons cannot employ graphite anyhow.

Thermal MSRs have a slower doubling time than fast-neutron breeders, despite the fact that their breeding ratios are lower.

Molten salts are one of the many methods that may be used for the cooling of MSRs.

Molten-salt-cooled solid-fuel reactors go by a few different names, including molten salt reactor system in the Generation IV proposal, molten salt converter reactors (MSCR), advanced high-temperature reactors (AHTR), and fluoride high-temperature reactors. All of these names refer to the same type of reactor (FHR, preferred DOE designation).

FHRs are unable to simply reprocess fuel and have fuel rods that need to be produced and certified. This process may take up to twenty years from the time the concept is first conceived. The FHR maintains the safety and economic benefits of a low-pressure, high-temperature coolant, which are characteristics that are also shared by liquid metal cooled reactors. Notably, there is no production of steam in the core, as there is in BWRs, thus there is no need for a massive, high-priced steel pressure vessel (as required for PWRs). Because it can function at high temperatures, a Brayton cycle gas turbine that is both efficient and lightweight may be used for the process of converting the heat into power.

A significant portion of the research that is being done on FHRs right now is focused on developing tiny, compact heat exchangers that can cut down on molten salt volumes and the expenses that are connected with those quantities.

The corrosive potential of molten salts may be rather significant, and this potential grows as the temperature rises.

Regarding the main refrigeration circuit, It is essential to have a material that is resistant to corrosion even when subjected to high temperatures and strong radiation.

Experiments show that Hastelloy-N and similar alloys are suited to these tasks at operating temperatures up to about 700 °C.

However, There is a lack of operational experience.

Still higher operating temperatures are desirable—at 850 °C thermochemical production of hydrogen becomes possible.

There has been no testing done to validate materials for this temperature range, notwithstanding the fact that carbon composites, molybdenum alloys (e.g.

TZM), carbides, as well as the possibility of using ODS alloys or materials based on refractory metals.

A private researcher has proposed that a solution may be to employ the new beta-titanium Au alloys, since this would not only permit operation at very high temperatures, but it would also increase the safety margin.

The salt mixes have been selected in order to make the reactor more functional and secure.

Fluorine has only one stable isotope (¹⁹F), and under the influence of neutron bombardment does not readily become radioactive.

In contrast to chlorine and the several other halides,, Fluorine also has a lower neutron absorption rate and moderates (slows) neutrons more effectively.

High temperatures cause fluorides with low valence to boil, despite the fact that several pentafluorides and hexafluorides boil at very moderate temperatures.

Before they can be reduced to their component parts, they need to be heated to extremely high temperatures.

When kept substantially below their respective boiling temperatures, molten salts of this kind are said to be chemically stable..

The fluoride salts have a low solubility in water, and do not create burnable hydrogen.

Chlorine has two stable isotopes (³⁵Cl and ³⁷Cl), as well as a slow-decaying isotope between them which facilitates neutron absorption by ³⁵Cl.

The presence of chlorides makes it possible to build rapid breeder reactors.

There has been a significant reduction in the amount of research conducted on reactor designs using chloride salts.

Chlorine, unlike fluorine, must go through the purification process in order to separate the heavier stable isotope, ³⁷Cl, thus reducing production of sulfur tetrachloride that occurs when ³⁵Cl absorbs a neutron to become ³⁶Cl, then degrades by beta decay to ³⁶S.

Lithium must be in the form of purified ⁷Li, because ⁶Li effectively captures neutrons and produces tritium.

Even if pure ⁷Li is used, The creation of substantial amounts of tritium is triggered by salts containing lithium, analogous to nuclear power plants using heavy water.

In order to lower their melting points, reactor salts are often found in mixes that are near to eutectic. Because of its low melting point, salt may be melted more easily at startup, and there is less of a chance that the salt will freeze when it is cooled in the heat exchanger.

Because fused fluoride salts have a relatively large redox window, the redox potential of the fused salt system is amenable to modification. With the addition of beryllium, the compound known as fluorine-lithium-beryllium (or FLiBe) may be used to reduce the redox potential and almost do away with corrosion. However, due to the fact that beryllium is a very poisonous element, additional safety measures will need to be included into the design in order to prevent any of it from being released into the environment. A wide variety of different salts also have the potential to induce corrosion in piping, particularly if the reactor is hot enough to produce highly reactive hydrogen.

To date, The majority of studies have focused on FLiBe, mainly due to the fact that lithium and beryllium are relatively good moderators and combine to generate a eutectic salt combination with a lower melting point than each of the component salts.

In addition, neutron doubling may occur in beryllium, Increasing the efficiency of the neutron economy.

After taking in one neutron, the nucleus of beryllium will engage in this process, which will result in the release of two neutrons.

Because of the gasoline that contains salts, generally 1% or 2% (by mole) of UF4 is added.

Fluorides of thorium and plutonium were also used at one point.

ORNL was the first place in the world to discover methods for preparing and working with molten salt. The removal of oxides, sulfur, and metal contaminants is the objective of the purification process used on salt. The presence of oxides might lead to the deposition of solid particles during the operation of the reactor. At the operating temperature, sulfur's corrosive assault on nickel-based alloys necessitates their removal so that the process may continue. For the purpose of corrosion control, structural metals like chromium, nickel, and iron need to be removed.

A water content reduction purification stage using HF and helium sweep gas was specified to run at 400 °C.

Oxide and sulfur contamination in the salt mixtures were removed using gas sparging of HF – H2 mixture, with the salt heated to 600 °C.

An benefit that may come with using an MSR is the potential of online processing.

Processing on a continuous basis would result in a lower stockpile of fission products, By eliminating fission products that have a large neutron absorption cross-section, corrosion may be controlled and the neutron economy can be improved, especially xenon.

Because of this, the MSR is an excellent choice for use in the neutron-poor thorium fuel cycle.

Online fuel processing can introduce risks of fuel processing accidents,: 15 which can trigger release of radio isotopes.

In some circumstances involving the breeding of thorium, the intermediate product protactinium ²³³Pa would be removed from the reactor and allowed to decay into highly pure ²³³U, an appealing component for use in the manufacture of bombs.

Designs that are more up to date suggest using one with a lower specific power or a second thorium breeding blanket.

This results in a dilution of the protactinium to such a degree that only a small fraction of the protactinium atoms are able to absorb a second neutron or proton, via a (n, 2n) chemical reaction (in which an incident neutron is not absorbed but instead knocks a neutron out of the nucleus), generate ²³²U.

Because ²³²U has a short half-life and its decay chain contains hard gamma emitters, It reduces the desirability of the isotopic composition of uranium for use in bomb production.

This gain would come with the increased expenditure of a bigger fissile inventory or a two-fluid design with a significant amount of blanket salt. However, it would be possible to achieve this benefit.

Although the essential technology for recycling fuel salt has been shown, it has only been done so on a laboratory scale. The conduct of research and development to build an economically viable fuel salt cleaning system is a precondition for the construction of full-scale commercial reactors.

In nuclear power plants, reprocessing refers to the process of chemically separating fissionable uranium and plutonium from spent fuel.

A comprehensive literature assessment from the year 2020 comes to the conclusion that there is