Thorium - Revision history

RichardWSmith: /* Carbonyl chemical reactions */ Added link.

2024-09-23T22:25:03Z

Carbonyl chemical reactions: Added link.

RichardWSmith: Added link.

2024-08-26T18:40:51Z

Added link.

RichardWSmith: Removed redundant sentence because it was not needed and because it was repetitive. Also two sentences said the same thing twice.

2024-08-26T18:38:38Z

Removed redundant sentence because it was not needed and because it was repetitive. Also two sentences said the same thing twice.

RichardWSmith: /* Concentration of thorium */ Fixed grammar.

2024-08-26T18:31:58Z

Concentration of thorium: Fixed grammar.

RichardWSmith: /* Concentration of thorium */ fixed grammar in sentence.

2024-08-26T18:31:23Z

Concentration of thorium: fixed grammar in sentence.

RichardWSmith: Added citation. Made wishy-washy sentence clearer & stronger.

2024-08-26T18:29:58Z

Added citation. Made wishy-washy sentence clearer & stronger.

Michel Lamontagne at 19:08, 29 November 2022

2022-11-29T19:08:54Z

RichardWSmith: Added a reference.

2022-11-24T06:14:55Z

Added a reference.

RichardWSmith: Added an additional problem with delaying processing the fission products.

2022-11-24T06:11:00Z

Added an additional problem with delaying processing the fission products.

RichardWSmith: /* Concentration of thorium */ Added reference.

2022-11-23T18:39:05Z

Concentration of thorium: Added reference.

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 ==Carbonyl chemical reactions==
-This paper suggests that Th can form carbonyl compounds from carbon monoxide gas.<ref>https://escholarship.org/uc/item/06g0m4mr</ref>  Since carbonyl reactors will likely be used on Mars, if thorium can be concentrated this way, it would be a 'free' by-product of pulling nickel, cobalt, iron, titanium, vanadium, ruthenium, chromium, and other metals out of the regolith.  (This won't really be free, because each carbonyl would require different temperatures & pressures to form; spending time and power for each.  So the reactor would run at one set of conditions to extract one type of metal, and then run at different temperatures and pressures to extract the next.  But so long as the thorium carbonyl can be formed within the range of the reactor, it won't require exotic efforts to pull it out of the low grade ore.)
+This paper suggests that Th can form carbonyl compounds from carbon monoxide gas.<ref>https://escholarship.org/uc/item/06g0m4mr</ref>  Since carbonyl reactors will likely be used on Mars, if thorium can be concentrated this way, it would be a 'free' by-product of pulling nickel, cobalt, iron, titanium, vanadium, ruthenium, chromium, and other metals out of the regolith.  (This won't really be free, because each carbonyl would require different temperatures & pressures to form; spending time and power for each.  So the reactor would run at one set of conditions to extract one type of metal, and then run at different temperatures and pressures to extract the next.  But so long as the thorium carbonyl can be formed within the range of the reactor, it won't require exotic efforts to pull it out of the low grade ore.) See [[Metal carbonyl]] for more information.
 ==References==

← Older revision		Revision as of 18:40, 26 August 2024
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	Note that as the U233 is bred, a small amount of U232 is also created. This decays releasing powerful gamma rays twice in its early decay chain, which is bad and good. (Bad in that the reactor core is even MORE radioactive, good in that in makes U233 less attractive for atom bomb making.)		Note that as the U233 is bred, a small amount of U232 is also created. This decays releasing powerful gamma rays twice in its early decay chain, which is bad and good. (Bad in that the reactor core is even MORE radioactive, good in that in makes U233 less attractive for atom bomb making.)
		+
		+	A molten salt reactor called a [[LFTR]] is designed to breed Thorium into U233.

	==Cost to refine & use thorium==		==Cost to refine & use thorium==

@@ Line 9: / Line 9: @@
 ==Concentration of thorium==
-The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>.  See map.  Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration from 500ppm to 25,000 ppm of Thorium.  Naturally concentrated deposits are welcome, but are not needed to make Thorium economical on Mars.<ref>https://aip.scitation.org/doi/pdf/10.1063/1.4972913</ref> <ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> Mines producing other metals could be utilized, many which produce a waste stream enriched in thorium.<ref>https://trace.tennessee.edu/cgi/viewcontent.cgi?article=3397&context=utk_chanhonoproj</ref> Other mines occasionally produce tailings enriched in thorium.<ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref>
+The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>.  See map.  Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration from 500ppm to 25,000 ppm of Thorium.  Naturally concentrated deposits are welcome, but are not needed to make Thorium economical on Mars.<ref>https://aip.scitation.org/doi/pdf/10.1063/1.4972913</ref> <ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> Mines producing other metals could be utilized, many which produce a waste stream enriched in thorium.<ref>https://trace.tennessee.edu/cgi/viewcontent.cgi?article=3397&context=utk_chanhonoproj</ref><ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref>
 This page: [[Radioactive Rarity on Mars]] discusses the apparent rarity of radioactive elements on Mars.

@@ Line 9: / Line 9: @@
 ==Concentration of thorium==
-The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>.  See map.  Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration from 500ppm to 25,000 ppm of Thorium.  Naturally concentrated deposits are welcome, but not needed to make Thorium economical on Mars.<ref>https://aip.scitation.org/doi/pdf/10.1063/1.4972913</ref> <ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> Mines producing other metals could be utilized, many which produce a waste stream enriched in thorium.<ref>https://trace.tennessee.edu/cgi/viewcontent.cgi?article=3397&context=utk_chanhonoproj</ref> Other mines occasionally produce tailings enriched in thorium.<ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref>
+The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>.  See map.  Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration from 500ppm to 25,000 ppm of Thorium.  Naturally concentrated deposits are welcome, but are not needed to make Thorium economical on Mars.<ref>https://aip.scitation.org/doi/pdf/10.1063/1.4972913</ref> <ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> Mines producing other metals could be utilized, many which produce a waste stream enriched in thorium.<ref>https://trace.tennessee.edu/cgi/viewcontent.cgi?article=3397&context=utk_chanhonoproj</ref> Other mines occasionally produce tailings enriched in thorium.<ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref>
 This page: [[Radioactive Rarity on Mars]] discusses the apparent rarity of radioactive elements on Mars.

@@ Line 9: / Line 9: @@
 ==Concentration of thorium==
-The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>.  See map.  Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration from 500ppm to 25,000 ppm of Thorium.  Naturally concentrated deposits are welcome, but not needed to make Thorium economical on Mars.<ref>https://aip.scitation.org/doi/pdf/10.1063/1.4972913</ref> <ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> mines could be utilized, which typically produce a waste stream enriched in thorium.<ref>https://trace.tennessee.edu/cgi/viewcontent.cgi?article=3397&context=utk_chanhonoproj</ref> Other mines occasionally produce tailings enriched in thorium.<ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref>
+The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>.  See map.  Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration from 500ppm to 25,000 ppm of Thorium.  Naturally concentrated deposits are welcome, but not needed to make Thorium economical on Mars.<ref>https://aip.scitation.org/doi/pdf/10.1063/1.4972913</ref> <ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> Mines producing other metals could be utilized, many which produce a waste stream enriched in thorium.<ref>https://trace.tennessee.edu/cgi/viewcontent.cgi?article=3397&context=utk_chanhonoproj</ref> Other mines occasionally produce tailings enriched in thorium.<ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref>
 This page: [[Radioactive Rarity on Mars]] discusses the apparent rarity of radioactive elements on Mars.

@@ Line 6: / Line 6: @@
 |abundance=}}Thorium, ''[[Elements on Mars|Periodic table]] Th'', is present on [[Mars]], however, its surface concentration seems to be lower than on Earth.<ref name=":12">Map of Martian Thorium at Mid-Latitudes,  JPL '' Map of Martian Thorium at Mid-Latitudes '', https://www.jpl.nasa.gov/spaceimages/details.php?id=PIA04257, March 2003.</ref> Thorium can be used to produce fuel for [[Nuclear power|nuclear reactors]] on Mars, including [[LFTR|Liquid Fluoride Thorium Reactors]], [[Nuclear_thermal_propulsion|nuclear thermal propulsion]] and [[Ion_thruster#Pulsed_Fission_Fusion_.28PuFF.29|nuclear pulsed propulsion]].
-Note that Thorium has a very long half life of 14 billion years, so the majority of the thorium that existed when the Earth formed is still here (Earth is 4.5 billion years old).  Thorium is not fissile, but it is fertile.  In other words, thorium does not spontaneously fission, but with neutron bombardment, it will transform into fissionable U233.
+Note that Thorium has a very long half life of 14 billion years, so the majority of the thorium that existed when the Earth and Mars were formed is still here (the planets are is 4.5 billion years old).  Thorium is not fissile, but it is fertile.  In other words, thorium does not spontaneously fission, but with neutron bombardment, it will transform into fissionable U233.
 ==Concentration of thorium==
-The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>.  See map.  Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration from 500ppm to 25,000 ppm of Thorium.<ref>https://aip.scitation.org/doi/pdf/10.1063/1.4972913</ref>  Naturally concentrated deposits would need to be found to make the use of Thorium economical on Mars in the long term.<span style="color: blue><sup>Citation Needed</sup></span>  Alternately the tailings of [[Rare Earths|rare earth elements]] mines<ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> mines could be utilized, which typically produce a waste stream enriched in thorium.<ref>https://trace.tennessee.edu/cgi/viewcontent.cgi?article=3397&context=utk_chanhonoproj</ref> Other mines occasionally produce tailings enriched in thorium.<ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref>
+The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>.  See map.  Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration from 500ppm to 25,000 ppm of Thorium.<ref>https://aip.scitation.org/doi/pdf/10.1063/1.4972913</ref>  Naturally concentrated deposits might need to be found to make the use of Thorium economical on Mars in the long term.<span style="color: blue><sup>Citation Needed</sup></span>  Alternately the tailings of [[Rare Earths|rare earth elements]] mines<ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> mines could be utilized, which typically produce a waste stream enriched in thorium.<ref>https://trace.tennessee.edu/cgi/viewcontent.cgi?article=3397&context=utk_chanhonoproj</ref> Other mines occasionally produce tailings enriched in thorium.<ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref>
 This page: [[Radioactive Rarity on Mars]] discusses the apparent rarity of radioactive elements on Mars.

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 * The next assumption that the thorium would burn up 100% is more suspect.  Typical fission power plants burn only 0.5% of their fuel before it is 'spent' and sent to long term waste.  However, current light water reactors were designed 70 years ago, and are WILDLY inefficient.  They use SOLID fuel oxides, clad in zirconium alloy cladding.  As the U235 fissions, the fuel elements swell and crack, releasing fission products (especially Xenon gas which is the worse neutron poison).  The fuel cylinders swell which puts pressure on the Zr cladding.  The zirconium cladding becomes brittle from neutron bombardment.  So before they break, the fuel rod is removed (say after 17 months), and a new one is put in its place.  The old fuel rods should be dissolved in acid, the fission products discarded, the 99.5% unburnt uranium recovered, converted back into a solid oxide and put back in a new fuel rod.  But the fission products are wildly, dangerously radioactive, and this chemical processing is expensive (especially considering the radioactivity).  Fresh fuel is so cheap, that it is more profitable to discard the used fuel rods, even tho more than 99% of the uranium has not fissioned.
-A LFTR burning thorium has a different philosophy.  The unburnt fuel STAYS in the reactor until it 'burns'.  The best place for these heavy nucleotides, is ''inside'' the reactor.  Ideally, the only thing leaving the reactor is heat and fission products. The molten salt is a LIQUID so you can do chemical processes on it directly.  Helium gas can be bubbled thru the working salt to pull out gases (such as xenon, radon, and tritium).  Some elements will plate out on cool surfaces.  (Tiny quantities of platinum, gold, iridium, etc. can be gained this way.)  As for metals that will dissolve in the molten salt, they can be removed with some effort which requires many successive chemical steps.  Originally it was intended to remove them constantly, but recently the idea is to let these products build up for a couple years, then remove the salt to a specialized plant to remove these wastes.  While the wastes are in the reactor, they will take up a small amount of volume, reducing the reactor's efficiency slightly (trivial), but some are neutron poisons which lower the reactor efficiency (important).  (This waste processing is the least developed part of LFTR.  It has been designed on paper, but little practical work has been done.)
+A LFTR burning thorium has a different philosophy.  The unburnt fuel STAYS in the reactor until it 'burns'.  The best place for these heavy nucleotides, is ''inside'' the reactor.  Ideally, the only thing leaving the reactor is heat and fission products. The molten salt is a LIQUID so you can do chemical processes on it directly.  Helium gas can be bubbled thru the working salt to pull out gases (such as xenon, radon, and tritium).  Some elements will plate out on cool surfaces.  (Tiny quantities of platinum, gold, iridium, etc. can be gained this way.)  As for metals that will dissolve in the molten salt, they can be removed with some effort which requires many successive chemical steps.  Originally it was intended to remove them constantly, but recently the idea is to let these products build up for a couple years, then remove the salt to a specialized plant to remove these wastes.  While the wastes are in the reactor, they will take up a small amount of volume, reducing the reactor's efficiency slightly (trivial), but some are neutron poisons which lower the reactor efficiency (important).  (This waste processing is the least developed part of LFTR.  It has been designed on paper, but little practical work has been done.)<ref>https://en.wikipedia.org/wiki/Liquid_fluoride_thorium_reactor#Removal_of_fission_products</ref>
 However, if the reactor only burns up (say) 80% of its fuel rather than 100%, the cost of the fuel is still insignificant compared to value you can gain from the reactor.  (You can also make the reactor (say) 25% bigger if the amount of energy is a concern.)