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GOOD NEWS!!!!!!! India's carbon dioxide emissions will "only" double by 2030.

Good News

Currently the per capita carbon dioxide emissions of an Indian is roughly 1.7 MT/yr, compared to 16.6 for Americans.

The caption:

Energy-related CO2 emissions history of China (red), the US (yellow), the EU28 (blue) and India (purple). Per capita figures in 2014 are given to the right-hand side of the chart. Note that the data in this figure include negligible amounts of non-CO2 gases from other fuels and fugitive emissions which could not be segregated in the dataset. Source: WRI Climate Analysis Indicators Tool (CAIT)

We are superior, of course, to Indians, since we worship Elon Musk and Tesla cars, but a bad person not prone to celebrating our grand victory over climate change here by continuous chanting of "watts...watts...watts" might note that if India, with a population estimated at 1.324 billion people had per capita consumption equal to the United States, 16.6 tons per human being, their emissions would be 22 billion tons.

Despite the grand victory of solar and wind, last year the world dumped approximately 35 billion tons of carbon dioxide into the planetary atmosphere, a world record. We zipped past 400 ppm of carbon dioxide in the atmosphere two years ago, and no one now living will ever see a quantity smaller than that ever.

But, old person that I am, so ignorant as to believe that a political philosophy that ignores human poverty is both morally bankrupt and environmentally unsustainable, well, I need to get with the program.

ELON MUSK IS SAVING THE WORLD!!!!! Rocket ships!!!!!! Electric Cars!!!!!! Solar Roofs!!!!!

Anyway. How dare Indians think they should live as we do?

I have to stop giving a shit; I have to stop believing that reality matters; I have to stop caring about the future...

Who do I think I am?

There is no political will, anywhere, to do anything other than mutter platitudes.

Spitting in the wind only leaves you with drool on your face.

A Scientific Rationale For Pursuing New Immobilization Forms For So Called "Nuclear Waste."

The paper from the primary scientific literature that I will discuss in this post is this one: Hierarchical Materials as Tailored Nuclear Waste Forms: A Perspective, (Hans-Conrad zur Loye et al, Chem. Mater., 2018, 30 (14), pp 4475–4488). This paper was formally released last month.

Let me state at the outset, as anyone who is familiar with my writings will know, I disagree with the concept of there being such a thing as so called "nuclear waste," my objection stemming from the belief that nothing which is extremely useful can be considered as "waste."

Let me be clear:

As I approach the end of my life, I am more and more firmly convinced that all of the materials is used nuclear fuel are not merely useful, but that their use will be essential - absolutely critical! - to future generations if they are to recover from the brutal and criminal destruction of the planetary ecosphere that our generation has foisted through indifference, wishful thinking, pure ignorance and pure self absorption and venality on all future generations.

This is the thesis of nearly all of my writings in this space.

Although we have clearly behaved as we hate all young people, it is my privilege, via contact with them through my two sons, to have met many of these young people who will suffer the consequences of what we have done. My general impression is that these young people coming up have the "right stuff." They are smarter than we are or than any of us were. Many seem to have the power to "think anew," to use Lincoln's beautiful locution. Previous generations far more admirable than ours proved to be derived their greatness from great challenges. Probably no generation has faced a challenge greater than the one we are leaving, the destruction of the planetary atmosphere, but perhaps, with the "right stuff," perhaps they'll rise to a kind of greatness the world has never seen.

One can only hope.

Earlier generations had some idea about the value of fission products and behaved accordingly. A while back in this space I wrote about the recovery of cesium-137 from the "waste" tanks at the Hanford Nuclear Weapons plant: 16 Years of (Radioactive) Cesium Recovery Processing at Hanford's B Plant. Some of the radiocesium sources obtained from this effort have been distributed for use, not as many as should have been so distributed to be sure, but the idea that these materials have value was clearly in the minds of the people who composed the esoteric document referenced in that post which described the processing, a document with the less than poetic title, "RHO-RE-SA-169."

The accumulation and fate of fission products is covered by what are known as the Bateman equations.

One (albeit greatly simplified) result from the use of these equations which I am particularly fond of utilizing in my private calculations is this one:

(This image comes from this link: OSU extended campus NES481/581.)

It should be obvious to anyone having completed a basic pre-calculus course in high school or college that as x → ∞ this function approaches zero.

This is an equation for secular equilibrium in a system in which the rate of formation is constant, in which the accumulation of a radionuclide asymptotically approaches a maximum dictated by its decay constant, λ, the decay constant in turn being nothing more than the natural logarithm of the number 2 divided by the half-life of the radionuclide in question. Ap in this equation is itself a function of the creation rate of the radionuclide. The creation rate for any nuclear power plant or, for that matter, all of the world's nuclear power plants can be estimated with fair accuracy if one has a feel for the fission yield of a particular nuclide being fissioned in the fuel and if the power of the reactor is more or less constant. Information about fission yields in turn is readily publicly available, for example from the National Nuclear Data Center at Brookhaven National Laboratory.

For example, using this resource, one can calculate that the sum of all fission produced nuclei decaying through the particularly valuable radionuclide cesium-137 to stable barium-137 in my personally preferred fission system, the fast fission of plutonium, is, to a first approximation, 6.49%.

Note as well, however that the aforementioned equation is not the equation for secular equilibrium between two radioactive species, since Ap here is essentially a constant, whereas the parent nucleus in a secular equilibrium between two radioactive species is itself also decaying.

In the 21st century, largely owing to the selective attention of anti-nukes who couldn't give a shit about how many people die from air pollution, heat waves, or for that matter, fecal waste, the nuclear industry effectively didn't grow at all. This is a great tragedy for humanity as a whole, and will cause great loss and suffering, but it is a fact. The amount of primary energy produced by the nuclear industry has remained more or less constant, somewhere around 28.4 EJ/year out of 576 exajoules that were being consumed each year as of 2016.

IEA 2017 World Energy Outlook, Table 2.2 page 79 (I have converted MTOE in the original table to the SI unit exajoules in this text.)

This figure, 28.4 exajoules, by the way, dwarfs the amount of energy produced by the popular but otherwise toxic, expensive and useless solar and wind industries combined, but it is what it is. Public appeals to stupidity, fear and ignorance are often successful, which explains why we have an ignorant, orange, corrupt, racist pig living in the White House, among other things. Anti-nuke rhetoric has been successful at stopping the growth of nuclear energy, through exactly the same kind of qualitative appeals to fear and ignorance. Conceivably, over the long term, the damage done by anti-nukes will actually outstrip the damage done by the orange pig in the White House.

Many years ago I built a spreadsheet using the equation above that I use to do back of the envelope calculations of the maxima that can be obtained for any particular nuclide that is decaying outside of a neutron flux, i.e. those resulting from direct fission or the decay of short lived precursors, isotopes that some people call nuclear "waste," at least for those nuclei that have very low neutron capture cross sections.

(This spreadsheet would not be useful for nuclei having as themselves, or as precursors, high neutron capture cross sections. For example it would not be useful for calculating the amount of Cesium-135 in used nuclear fuel because its precursor, Xenon-135 has one of the highest neutron capture cross sections known and is thus this isotope is nearly quantitatively consumed in the reactor, becoming the stable xenon isotope 136, and thus preventing the accumulation of much cesium-135. The high neutron capture cross section of Xenon-135 is responsible for the effect discovered by Manhattan Project scientists known as Xenon poisoning – misplaced concern that this effect would interfere with the unauthorized experiment being conducted that played a role in the poor decisions that led to the reactor explosion at Chernobyl.)

If one types in a particular annual energy figure (in exajoules) in a cell in one of these spreadsheets, it will calculate the maximal amount of a neutron transparent nuclide that can calculate at that power level, power referring to the total energy production divided by one year's time. (As I often point out, I can't stand the scientific illiteracy routinely exploited by the failed, expensive, and toxic solar industries when they deliberately misrepresent peak power as being the equivalent of energy.) It will also calculate the amount of such a fission product present any particular year, as the system approaches, again asymptotically, the level at which it is decaying at the same rate as it is formed.

Two major radionuclides found in used nuclear fuel are more or less transparent to neutrons, Sr-90, and Cs-137. Their half-lives are each on the order of three decades. Thus they are not subject to facile transmutation, at least not with thermal fission neutrons. The former, a pure beta emitter, is generally only useful as a source of portable heat and as a source of its short lived radioactive decay product yttrium-90 for medical treatment, but the latter has many more important uses. I will therefore focus on Cs-137 here.

It can be shown to a first approximation that at 28.4 exajoules per year of primary energy using the fission yield of U-235 which is still (albeit regrettably) the major nuclide powering fission reactors, that the maximal amount of Cs-137 that can be obtained would be - after hundreds of years at this power level - would be approximately 577 metric tons. The amount that actually exists 18 years into the 21st century and created in this century, is roughly 195 metric tons, with the growth rate now diminished to 8.9 tons per year from the figure 18 years ago, which was 12.8 tons per year during the first year of this century.

Humanity will almost certainly not survive in a form we would recognize today if this level of nuclear energy were not to increase drastically over a period of the next 32 years, but at the 50 year point at 28.4 EJ/year, cesium-137 would be accumulating at 4.2 tons per year, with, because of the larger inventory at that point, roughly 395 tons, 8.6 tons would be decaying to stable barium-137 each year.

These figures are, by the way, only a fraction of the total Cesium-137 available, since they account for only the cesium accumulated in the world's power reactors in this century, and they do not account for fission products accumulated in the 20th century, including materials available at places like Hanford. For example, 33.8% of the Cs-137 from my much beloved nuclear reactor at Oyster Creek, which is near where I live, that was originally in the fuel removed after its first fuel cycle in 1971, is still present, with 76.2% of it having decayed, without a single loss of life, to stable non-radioactive Ba-137.

Thus the total amount of Cs-137 available to do work to restore the environment is small. Nevertheless, it has properties which make it possible for it to do things that no other substance can do as well.

Suppose for instance, as a thought experiment, that we had 1370 tons of Cs-137 available, 10,000 moles, and that we chose to utilize the well-known ability of aqueous solutions cesium hydroxide, CsOH, to capture carbon dioxide from the air. Suppose, optimistically, that we arranged the system in such a way that it could cycle through 6 capture and release cycles day, each absorbing one mole of carbon dioxide (as bicarbonate) per mole of cesium hydroxide, while, as a side benefit, destroying several major ozone depleting and greenhouse gases polluting our atmosphere.

CsOH + CO2 + ↔ CsHCO3

Thus we would be able to capture only 60,000 moles of carbon dioxide per day, or a little over 2600 tons of CO2 per day, a little less than a million tons per year. This is a trivial amount compared to the 35 billion tons per year (95 million tons per day) we are now dumping each year as we sit Godot like, chanting about the grand "renewable energy" nirvana that never comes.

Of course, even though carbon dioxide's effect on the weather is dramatic, the actual concentration is rather low, having risen to only 411 ppm, with average increases in the 21st century having risen to approximately 2.2 ppm/year. This means to remove 1 million tons of carbon dioxide from the atmosphere using the cesium-137 system I described above, the amount of air that would need to be processed would be 2.4 billion tons.

The total dry mass of the atmosphere is taken to be 5.1352 exakilograms, (5.1352 X 10^18 kg) or 5.1352 petatons. Thus the amount of air to be processed by a cesium-137 carbon dioxide capture system to capture 1 million tons of carbon dioxide in a year would be insignificant relative to the total mass of the atmosphere. Only 0.000047% of the atmosphere would be processed in an entire year.

This should give a sense of exactly how difficult an engineering challenge the reversal of our generation's irresponsibility and contempt for future generations is. (Happily, the difficulty is somewhat ameliorated by the fact that the volume concentration of carbon dioxide - as carbonate, bicarbonate, and soluble carbon dioxide in seawater is much higher than it is in air - any remotely workable path toward the removal of carbon dioxide from the atmosphere must proceed through the avenues of seawater and, to a lesser viable extent, the capture of carbon dioxide from biomass combustion or - better - reformation.)

However another factor comes into play which might actually be more important, and that, again, is this cesium-137 mediated process would effectively destroy a number of other important climate forcing gases, including many which are major players in the destruction of stratospheric ozone which protects life on earth from UV radiation. (Life on land became possibly when the atmosphere began to obtain quantities of oxygen high enough to generate an ozone layer.)

Here is a nice list, from the Lawrence Berkeley Livermore National Laboratory of climate forcing gases, their global climate forcing potential, their concentrations, and their atmospheric lifetime: Recent Greenhouse Gas Concentrations. Two of the gases listed are utilized in radiation dosimeters, the dielectric transformer and energy conservation gas sulfur hexafluoride and nitrous oxide - “laughing gas,” – a substance produced by the breakdown of fertilizers. Such use implies that they are rapidly degraded by radiation, and in fact, the radiation flux in the upper atmosphere is their only natural sink. Of these two, nitrous oxide is also a powerful ozone depleting agent, one that cannot be, by the way, banned by treaty, since it is a byproduct of agriculture.

Eight of the gases are CFC's which were banned by the only successful international treaty ever put into effect, the Montreal Protocol, although recently it has been learned that China is cheating on this treaty. (The Kyoto protocols and the Paris agreement have been, obviously, ineffective and useless. Some of this result comes from general contempt for science by certain governments, including the government of the United States, and some from the quixotic attempt to make the solar and wind industries significant checks on climate change, something they have not been able to do, are not able to do, and will never be able to do.)

One of the listed gases is increasing because of the increasing reliance on dangerous natural gas to cover for the grotesque failure of the wind and solar industries to become effective; this of course, is methane.

Another of the gases is ozone itself. While stratospheric ozone is essential for terrestrial life on earth trophospheric ozone is a health hazard for plants and animals, including among the most dangerous animals, human beings.

Of course, CFC's (and nitrous oxide) destroy ozone, but only when they are exposed to radiation . Right now, the only major source of high energy radiation in the upper atmosphere, is UV radiation, and x-rays emitted by the sun. The destruction of ozone by CFC's and by nitrous oxide is a chain reaction; essentially they are catalytic reactions wherein the original compound is reformed by recombination.

Here's a picture, among many available on the internet, showing the reaction for CFC-12:


Note that in this picture, one possible fate for the chlorine radicals present and catalyzing the destruction of ozone is to recombine with the difluorochloromethane radical to regenerate the original CFC-12, meaning that not only is the chlorine radical catalytic, so is the CFC-12 itself. However, no catalyst, neither one intentionally designed nor one unintentionally active, is immortal. All are eventually rendered inactive or, in the case of CFC's, destroyed.

The ultimate destruction of a CFC – it may go through thousands of catalytic cycles before the reaction takes place – is this: Radiation splits water as well as CFC’s, thus producing the highly oxidizing ●OH radical and the hydrogen radical. If either of these radicals were to react with the chlorodifluoromethane radical, the catalytic nature of the molecule would be terminated, more readily so in the case, where the ●OH radical were the combining agent. The combination of an ●OH radical with a chlorodifluoromethane radical produces hydroxychlorodifluoromethane. Hydroxydifluorochloromethane is unstable: It rearranges, eliminating hydrochloric (or hydrofluoric) acid and fluorophosgene aka difluorocarbonyl (often written as “fluorocarbonyl”), aka COF2, or chlorofluorophosgene, aka chlorofluorocarbonyl, aka COFCl.

By the way, one of the interesting things I learned while researching this post is that my long held assumption about the stability of trifluoromethanol, a compound related to chlorodifluoromethanol, which I assume spontaneously and quantitatively decomposed to give fluorophosgene with fast kinetics, with a half-life at best in seconds, turns out not to be true. The half-life of trifluoromethanol’s decay into fluorophosgene or chlorofluorophosgene is on the order of hours, not even seconds, never mind nanoseconds.

Atmospheric Chemistry of Hydrofluorocarbon 134a. Fate of the AlkoxyRadical CF30● (Wallington and Sehested, Environ. Sci. Technol., Vol. 27, No. 1, 1993)

If these reactions sound scary, they are nonetheless taking place right now. They have been taking place ever since the CFC's were introduced.

There is a long history of detecting these toxic compounds in the atmosphere:

First global observations of atmospheric COClF from the Atmospheric Chemistry Experiment mission (2004-2007) Fu et al Journal of Quantitative Spectroscopy & Radiative Transfer 110 (2009) 974–985.

Vertical Column Abundances of COF2 Above the Jungfraujoch Station, Derived from Ground Based Infrared Solar Observations Rinsland et al Journal of Atmospheric Chemistry 29: 119–134, 1998. (Rinsland was the first to actually detect the molecule in the atmosphere, back in 1986, although its presence had long been suspected.)

Hydrogen fluoride total and partial column time series above the Jungfraujoch from long‐term FTIR measurements: Impact of the line‐shape model, characterization of the error budget and seasonal cycle, and comparison with satellite and model data (Duchatelet et al 2010 Journal of Geophysical Research Atmospheres Volume 115, Issue D22 27 November 2010)

Nevertheless the observed kinetics of these reactions are slow; the CFC’s banned by the Montreal protocol that were released before the treaty took effect are still present, albeit in lower amounts.

There are several reasons for this. One is that the pressure is very low in the upper atmosphere and molecules don’t meet often enough to react. In terms of the destruction of a CFC, it is essential that a hydroxide radical (or hydrogen radical) provided by splitting water collide with a radical formed by a CFC radical formed by radiolytic splitting off of a chlorine radical, the latter running about an catalytically breaking up ozone molecules catalytically. However the vapor pressure of water is extremely low in the upper atmosphere, with the majority of the water actually being in the form of ice. Although it is known that reactions can and do take place on ice crystals, it is almost certain that the majority of radiation mediated water splitting takes place in the gas phase, i.e on the other side of the sublimation line in the phase diagram of water. More over the tendency for water to liquefy or solidify and fall as rain or snow removes water from the upper atmosphere, further diluting it.

Another factor is that the ozone depleting gases are relatively heavy. CFC-12 for instance has a molar mass of 120.9, compared with the mean molecular mass of air which is 29. By appeal to a distribution law known as the barometric distribution law it can be shown that even though enough CFC’s make it to the upper atmosphere to cause big trouble, the overwhelming bulk of them are concentrated in the lower atmosphere, the troposphere where far less radiation permeates, with the upper atmosphere being enriched in lighter gases relative to the heavier pollutants.

The upper border of the troposphere – the part of the atmosphere in which we live and which all weather basically takes place – is roughly 10,000 m, depending on the time of the year and temperatures. The decomposition of CFC’s takes place in the upper stratosphere. It can be shown by fairly straight-forward calculation using the barometric law, treating CFC-12 as an ideal gas, that 293K (room temperature) 99.2% of CFC-12 is present in the troposphere and only 0.8% is present in the stratosphere and ionosphere, whereas only – by the same calculation – 66.9% of “average” air is in the troposphere under the same conditions. (By the same crude calculation, 72.4% of the world’s oxygen is in the trophosphere.)

With this consideration it is easy to see why CFC’s (and for that matter HFC’s, their replacement) reside in the atmosphere for a long time if the only sink is solar based irradiation.

Now let’s consider the difference in a situation where air is pumped into a container having a solution of radioactive cesium-137 hydroxide near sea level. In the first kilometer of the troposphere, 38.3% of all atmospheric CFC-12’s are present, as opposed to 0.8% in the stratosphere. Since cesium-137 generates heat as it decays, the warm water exerts a significant vapor pressure, as does, albeit to a comparatively minor extent, the heat generated from the exothermic combination of acidic carbon dioxide with the hydroxide ion to form carbonate. Moreover the radiation field is far more intense. We know that the radiation we experience on a plane flight, while higher than what we experience at sea level is not particularly dangerous, whereas it is straight forward to make a solution of cesium-137 radioactive enough to be able to kill a human being with a short exposure at a few meters. Moreover, most of the decomposition molecules are either acidic or rapidly destroyed by strong base, cesium hydroxide being the strongest base that is stable in water.

When I was a kid I had a job doing organic synthesis using the war gas phosgene as a symmetric acylating agent. Phosgene is dicarbonyl chloride, COCl2, a molecule very similar to, albeit slightly less reactive than, COF2 (known, again, as fluorophosgene) or COClF (chlorofluorophosgene). The way I used to destroy excess phosgene was to bubble it through a solution of ammonia – it reacts with ammonia to form urea – and then, for any that go through the ammonia intact with a solution of sodium hydroxide, whereupon it formed sodium carbonate and sodium chloride in solution. Trust me, these reactions work quite well to destroy phosgene and its analogues.

Under these conditions we should expect that all of the CFC’s would have very short half-lives, and that in fact, the HFC’s as well. Moreover, a solution of radioactive cesium hydroxide will always contain some barium hydroxide formed as the decay product. Thus barium fluoride formed by the decomposition of these gases would precipitate out of solution: Barium fluoride is extremely insoluble.

An interesting thing about barium fluoride is that it is an excellent material for the down-conversion of gamma radiation into UV radiation. If titanium dioxide were present in some form in the system, one can imagine destroying a huge host of pollutants now troubling humanity.

Other gases destroyed would be N2O – decomposing into nitrogen and oxygen gas - and SF6, both greenhouse gases. SO3, sulfur trioxide, a serious acid rain pollutant, would also be removed; it would react with the basic solution to form sulfate, and ultimately barium sulfate (the mineral barite), also very insoluble. Moreover, by the same reactions that take place in the far more dilute upper stratosphere, tropospheric ozone – itself a serious air pollutant when it appears in the lower atmosphere – would be effectively reduced or destroyed completely.

Earlier I mentioned that if we had 10,000 moles of cesium-137 we’d be able to remove about 1 million tons of carbon dioxide per year. However, by appeal to the Lawrence Berkeley Lab tables linked above, accounting for all of the greenhouse gases destroyed – the exception being methane and even it might be converted to methanol, formaldehyde, formic acid or carbon dioxide under these conditions – and weighted for their much higher global warming potential with respect to carbon dioxide, that this process with 10,000 moles of cesium-137 would actually be the equivalent of removing 1.2 million tons of carbon dioxide.

Nevertheless, as aforementioned, this is still a trivial amount of carbon dioxide, approximately 0.0034% of the amount of carbon dioxide, 35 billion tons we are currently dumping into the planetary atmosphere each year while we wait for the grand “renewable” energy nirvana that never comes.

As a practical matter, albeit in this impractical thought experiment, the amount of carbon dioxide removed would undoubtedly be somewhat larger, since cesium-137 would also contain the only natural isotope of cesium, cesium-133, itself a fission product, as well as small amounts of cesium-135, the formation of which would be limited, again, by the extraordinarily high neutron capture cross section of its xenon-135 precursor. Cesium-134 would also be present, although it does not form by direct fission simply because its putative precursor is the stable gaseous isotope xenon-134. Cesium-134 would only form by neutron capture in non-radioactive cesium-133. Also, there would be no good reason to remove the fission product rubidium, a cogener of cesium. (Natural rubidium is, by the way, radioactive, because of the presence of the very long lived isotope Rb-87 which has survived since the supernova nuclear explosion that created the majority of the elements found on this planet.)

Moreover, in order to produce 6 cycles a day, perhaps using radiostrontium oxide formed by the calcination of strontium carbonate using some, if not only, self-generated heat to rapidly regenerate the cesium hydroxide from the cesium bicarbonate solution, pumps would be required, and pumps require energy. Probably, since the decay of cesium generates heat, it would be possible to affect this system by simply compressing air over the radioactive solution, causing the compressed air to heat, and, upon release, allow it to expand against a turbine, i.e. use it a Brayton cycle type arrangement. However, the power output of 10,000 moles of cesium-137 is very modest, roughly 1.3 MW, enough to run an industrial scale compressor perhaps suitable for processing a few billion tons of air, as well as a few water pumps and filtration devices, but not much else.

Were we to make what I personally regard as the right choice, in lieu of the unworkable and continuously failing choices we are in fact making, and produce all, or nearly all, of our primary energy by nuclear means, let’s say 580 exajoules, the maximal amount of Cs-137 that could accumulate before it was decaying as rapidly as it is formed is on the order of 12,000 tons. We may compare this with US coal power carbon dioxide emissions in 2014, which was approximately 1,600,000,000 tons of carbon dioxide in the United States alone, and could ask ourselves which would be easier to contain for eternity. (We could ask ourselves, but we don’t ask ourselves, and that is the problem.) At 580 exajoules per year produced by nuclear fission, it would take more than 83 years for 10,000 tons of cesium-137 to accumulate. This is only a single order of magnitude higher than the figures I suggested above in my thought experiment. We might increase the amount of radioactive cesium by placing largely decayed cesium into a reactor’s neutron flux, by activating residual Cs-133 by transmuting it into Cs-134 and boosting the low activity of Cs-135 by transmuting it into Cs-136 (and smaller amounts of new cesium-137) but still, we wouldn’t be anywhere near producing enough radioactive cesium to make a real difference.

In the best case, therefore the system I proposed in the elaborate thought experiment above, using liquid solutions of radiocesium hydroxide to capture carbon dioxide, destroy HFC, CFC’s, N2O, and sulfur hexafluoride would remain trivial, and thus unlikely to be economically viable.

Nevertheless, it is a shame that the radiation generated by the decay of cesium is not doing whatever small work it might do for humanity, if not in removing carbon dioxide by a Rube Goldberg array of pumps, filters, turbines and compressed air tanks containing radioactive solutions, then at least in destroying the problematic greenhouse gases listed in the Lawrence Berkeley listing.

This aside disposed, the idea of using radiation to destroy the minor greenhouse and ozone depleting gases finally brings me to paper I promised to discuss above before launching into this elaborate diatribe of no consequence. That paper, again, is this one: Hierarchical Materials as Tailored Nuclear Waste Forms: A Perspective, (Hans-Conrad zur Loye et al, Chem. Mater., 2018, 30 (14), pp 4475–4488).

It's useful to reproduce the introduction of this paper, albeit including several statements that I regard as highly questionable:

The United States has spent more than half a century developing the nation’s nuclear arsenal and nuclear energy infrastructure. The scale of these activities has, and will continue to result in a significant quantity of radioactive waste. These materials are generally classified and dispositioned according to their hazard level. In the United States, three main categories are recognized: low-level waste (LLW), high level waste (HLW), and transuranic (TRU) waste. These wastes must be processed so that the radioactive and hazardous constituents become permanently stabilized and safely sequestered from the biosphere for millennia.

LLW contains short-lived radionuclides in relatively small amounts and includes materials like consumables, process chemicals, tools, etc. LLW poses relatively low risk to the biosphere and can be disposed of in shallow or above-ground vaults. HLW originates as irradiated reactor fuel, contains long lived radionuclides, and generally has high specific activity, which may be sufficient to generate significant heat. TRU waste, a classification unique to the United States, is that which is not classified as HLW but contains alpha-emitting TRU radionuclide elements in greater than 100 nCi/g concentrations and with half-lives greater than 20 years. TRU waste includes primarily contaminated tools, clothing, debris, process residues, etc., used in nuclear defense and energy program activities.1

Let me first dispose of the question of what the author's call "LLW" and suggest that a technology - one that I read about perhaps 5 or ten years ago, but which I assumed had not been commercialized – does in fact commercially exist for processing this material in a highly effective way.

A trade magazine description of the commercial process is here: Fluidized Bed Steam Reforming Technology.

Although the process is probably not identical, here is the paper, along similar lines I may have encountered years ago, which stuck in my mind, at least this is the paper I can easily find in my files touching on the subject: Recovery of radioactivity as solids from nonflammable organic low-level radioactive wastes using supercritical water mixed with RuO2 (Sugiyama et alJ. of Supercritical Fluids , 35 (2005) 240–246) The commercial process probably doesn’t use ruthenium dioxide (also available as a fission prioduct) but the idea upon which it touches is basically the same.

Under these conditions, all of the radioactive materials remain, in a more concentrated form, in the residues; the gases formed are almost certainly syn gas, a mixture of carbon oxides and hydrogen useful for making polymers, fuels, and other based carbon materials.

The radioactive materials left behind may be subject to treatment using the technologies considered in the paper now under discussion.

Now let me turn to the some comments in this intro which strike me, at least, as highly questionable. Let’s start with this one:

HLW, as its name suggests, generally poses the greatest risk to the biosphere and must be sequestered through deep geologic disposal, the safest established method.

While the word "generally" as used in this highly questionable sentence might be a useful qualifier, it's hardly strong enough to palliate the possibly absurd words I have place in bold, with special emphasis on the word "must."

I often link, in this space, published in one of the world's most prestigious medical journals with one of the highest impact factors among journals, Lancet, a comprehensive paper on risk assembled by a team of international experts funded by the Gates Foundation, that sought to examine all the measurable and major environmental factors responsible for mortality and morbidity in the entire world.

It's this one:

A comparative risk assessment of burden of disease and injury attributable to 67 risk factors and risk factor clusters in 21 regions, 1990–2010: a systematic analysis for the Global Burden of Disease Study 2010. (Updated reports from the Global Burden of Disease have recently been published, but I haven’t had a chance to go through it in its entirety and perhaps will discuss it in future posts.)

Since I'm generally referring to the indifference that anti-nukes who want to represent that Fukushima actually in important on scale - it isn't - I usually use it to point out that these people apparently don't give a shit about stuff that does matter, to wit, air pollution, I usually include this statement with the link:

For air pollution mortality figures see Table 3, page 2238 and the text on page 2240.

I just opened the full paper now. Table 3 is 3 pages long in small print and the air pollution death data represents, perhaps, 1/20th of page 2238, which is completely filled with 1/3 of table 3. Air pollution is further divided into three categories for 2010, ambient particulate air pollution, 3.5 million deaths, indoor air pollution, 3.2 million deaths, and ozone, 0.2 million deaths, for a total with 2 significant figures, of 6.9 million deaths, which I round up to 7 million given that the precision of these epidemiological measurements seems to be overstated, and that I'd guess that the accuracy (standard deviation) is probably, at best, +/- 10%. However imprecise the measurements are, they do get to a level of considerable detail, reporting for instance that occupational exposure to silica was responsible for about 16,000 deaths in 2010, occupational exposure to cadmium was responsible for about 550 deaths, and that occupational exposure to formaldehyde was around 700 deaths.

Nowhere in the paper does it refer to "occupational" exposure to what some people - idiots in my view - refer to as "dangerous nuclear waste."

Now this is not to imply that it is true that no one has ever been injured by handling nuclear fuel. It is known, for instance, that a criticality accident in Japan some years back killed a two people; it just wasn’t in 2010 – in was 1999. It may also be true that there are other deaths from handling nuclear fuel that may exist but are not measurable. However, this is speculation, and not science, since science is meaningless without measurement. Measurement, and only measurement distinguishes the truth or falsity of theory.

Facts matter, but only when they exist.

Of course, there are studies on the health of nuclear power plant workers. For example, here’s one: Mortality risk in a historical cohort of nuclear power plant workers in Germany: results from a second follow-up (Merzenich, H., Hammer, G.P., Tröltzsch, K. et al. Radiat Environ Biophys (2014) 53: 405). In this paper, it appears that overall, out of 8,972 nuclear power plant workers in 17 nuclear power plants, studied over a period between 1991 and 2008, 310 died, 126 of whom died from cancer. This is substantially less people than would have been expected to die both from cancer or from other causes in the general West German population. This is not to imply that radiation is good for you. It is possible that there is another cause for the general health of the workers that overwhelms the risk of radiation. The authors muse about the "healthy worker effect" which is simply a statement that in general, people who have good high paying jobs have better general health than those who are in low paying jobs or simply unemployed.

Germany by the way, has voted to kill people by shutting its nuclear plants.

Nevertheless, given the Lancet report stated above, and the absence of proof that nuclear power plant workers die at a rate substantially higher than coal miners it appears that there isn’t much data indicating anything at all about the safety of used nuclear fuels. Used nuclear fuels in many places, including the United States, are stored on the site they are generated, which is very different than, say coal waste, which is simply dumped in the atmosphere, thus guaranteeing that all living things will be exposed to it.

Thus a statement that anyone has demonstrated that any particular approach to handling used nuclear fuel represents the “safest established method” is at worst, pure speculation, and at best, theory. My guess is that it’s a little of both. It is difficult to establish that any particular choice is safer than another if no option has demonstrated a lack of safety, the endless and rather idiotic fetishes about so called “nuclear waste” notwithstanding.

Geologic disposal is a proposal to dump radioactive materials and then forget about them. By contrast, the use of radioactive materials to solve human problems is active; the people who are using them will be required to know where the materials are, how much there is, and what the effect of their use – which I contend will be generally positive – and thus, I speculate, will be much safer, since the uses I propose will save human lives.
Before proposing another thought experiment involving fission products that we might put in my backyard in order to reduce the environmental health risks that I, and my neighbors – whether they know it or not – face, let me return to some aspects of the first paper cited in this post.

The authors note that some earlier strategies for containing so called “nuclear waste” have major drawbacks. For instance, they write, about the traditional strategy of incorporating fission products in glass. These include crystallization events in some types of glasses so used, resulting in the formation of the sodium/potassium aluminosilicate nepheline which allows for the migration of certain radioactive elements within the structure. In addition they note the fact that the incorporation of volatile elements like cesium and (to a lesser extent) technetium involves heat resulting in radioactive vapors that can contaminate process equipment.

Nevertheless, radiocesium has been successfully incorporated into stable forms, as I noted elsewhere in this space and above, describing the isolation of what can be shown to be by direct calculation, ton scale quantities of cesium-137, and its incorporation into a phosphotungstate matrix, some of which has been distributed to licensees for use. Again: 16 Years of (Radioactive) Cesium Recovery Processing at Hanford's B Plant. (If one reads the original documents to which this post refers, one will learn that the process of isolation underwent several major changes over the 16 year period, the major changes being to the types of ion exchange agents utilized.)

Irrespective of this fact, the authors of the paper suggest that there are materials that may have properties that may well have properties that are superior to the cesium/sodium phosphotungstate utilized to create the Hanford radiation sources.

The discuss "hierarchical" materials. What are these? The authors write:

A simple and very practical working definition of a hierarchical structure is a material with structural motifs at various length scales, together forming a larger structure or framework. Nature has abundant examples of hierarchical materials and processes, a notable case being biomineralization, which is the process responsible for the formation of biomaterials, such as shells, bone, and teeth. These are formed by processes that generate hierarchically structured organic−inorganic composites. It is a bottom-up strategy starting at atomic and molecular scales with processes leading to the formation of higher scale building blocks, which in turn organize into complex hierarchical structures. Conceptually, hierarchical structures of interest for waste forms consist of porous assemblies, either repeating (crystallographically ordered) or nonrepeating (disordered), whose cavities will be occupied by crystalline or noncrystalline fillers. One approach to creating such materials relies on exploring porous structures such as crystalline salt inclusion materials (SIMs), metal−organic frameworks (MOFs), porous silica, and surface functionalized nanoparticles assembled into hierarchical constructs. Examples of fillers include salts, simple covalent molecular species, Prussian-blue analog (PBA) nanoparticles, and multimetallic nanoparticles, all either freely located inside molecular-scale framework structure pores or tethered/bonded to pore surfaces.

The multiscale motifs that assemble into the final hierarchical structure all play, individually as well as in the aggregate, important roles in potential waste sequestration materials. The multiscale structure allows us to optimize the chemical environments for different waste species and create a custom waste form that can simultaneously accommodate multiple, difficult to isolate radionuclides...

The authors then give a little tour of these types of structures, beginning with alloy nanoparticles that they model on the gold/copper (Au/Cu) system because this alloy is an alloy which forms spontaneously without melting, thus avoiding the need for high temperatures.

They share with us a little graphic of this system:

The caption:

Figure 1. Model Au–Cu system illustrating initial core–shell structure that can be processed at low temperatures to form a disordered alloy and/or intermetallic phase nanoparticle depending on composition. On the top are SEM images of particles represented by the drawings below.

This strikes me as interesting since, for a number of years, I've had an on and off interest in an interesting class of materials known as "Zintl Salts," which are salts inasmuch they are composed of both positive and negative ions. What makes these particular salts is that the negatively charged ions are pure metals, metals being species that are almost always under all other circumstances positively charged.

In fact, one of the most interesting such species is a Zintl salt of cesium, Cs4Pb9, in which a negative charge of -4 is distributed over a cluster of 9 lead atoms arranged in a nido-deltahedron, a monocapped square antiprism - a type of structure more typically associated with the structure of boranes and not, at least to my knowledge, not normally associated with lead. (cf. Deltahedral Clusters in Neat Solids: Synthesis and Structure of the Zintl Phase Cs4Pb9 with Discrete Pb9 4- Clusters (Evgeny Todorov and Slavi C. Sevov, Inorg. Chem. 1998, 37, 3889-3891)). This phase has some interesting thermodynamic properties (cf, for example Heat capacity of some liquid Zintl compounds: Equiatomic alkali–lead alloys (Marie-Louise Saboungi et al J. Chem. Phys. 89, 5869 (1988)) exhibiting heat capacity anomalies that suggests some wonderful nuclear applications, but as lead tends to shield radiation rather than allow for an intense flux, this type of application would not be useful for my thought experiment below. These heat capacity anomalies are thought to represent transitions “free metal atoms” and cluster forms, thought to persist through the liquid phase.

In any case, the authors of the hierarchical paper under discussion propose a three pronged approach to modeling alloys containing what they regard as “difficult to isolate” radionuclides. They write:

Efforts with model systems is leading to the fundamental understanding needed to develop systems containing problem radionuclides such as 137Cs and 99Tc, which will in turn be used to validate the approach. For that reason, a “Make, Measure, Model (3M)” strategy19 has been adopted to develop a quantitative understanding of the structure−composition− property relationships of multimetallic nanostructures through combined experimental and computational efforts integrating syntheses, characterization, and modeling.

The nanoscale nature of materials provides challenges in characterization and computational studies, further complicated should disorder occur. For example, a global challenge in the study of guest radionuclide atoms or ions in disordered nanoscale materials is differentiating between the signatures of the guest atom/ion, disorder, and size effects an exercise which is necessary to quantitatively describe the structure and predict properties. To address these, novel approaches are being introduced which are expected to provide new insights into the atomic and mesoscale structures.

(Again I have a problem with their locutions; I see 137Cs and 99Tc not as "problem radionuclides" but as "opportune radionuclides." )

Their modeling consists of straight up density functional theory (DFT) as well as a technique with which I personally have little familiarity and thus must learn more about, pair distribution functions, (PDF). They offer us some graphics - referring to their model alloy system, the gold copper system - detailing the kinds of results that PDF type calculations give.

The caption:

Figure 2. Examples of atomic structures that arise due to different combinations of first and second coordination shell chemical correlations in a nominal 50/50 Au/Cu solid solution. Positive correlations imply like pairs are preferred while negative correlations imply unlike pairs preferred. Gold colored spheres correspond to gold atoms, while blue ones correspond to copper atoms.

Now things get a little more interesting, as the authors describe a class of materials know as "salt inclusion materials," "SIMS."

They write:

Salt-Inclusion Materials. Another approach to the targeted development of new waste forms that simultaneously capture and store multiple radionuclides, including difficult to contain elements, such as cesium, technetium, and iodine, is salt-inclusion materials (SIMs). It is possible to create hierarchical, salt-containing framework structures that have the ability to trap numerous radionuclides through ion exchange, where a nonradioactive salt is replaced by radionuclides that are thereby immobilized within the covalent framework for long-term storage. Using high temperature molten salts as the reaction environment,26 we have prepared numerous examples of an intriguing class of materials, SIMs, that are inorganic framework structures containing voids occupied by an ionic salt lattice. This salt lattice can range from very simple molecular structure, a halide anion surrounded by several alkali cations,27 to more complex dimers,28,29 chains,30,31 slabs,32 and even interwoven 3D salt constructs.

They then describe in the text a structured uranyl silicate containing potassium/sodium fluoride salt trapped (actually complexed) within nanopores in the structure, and helpfully provide us with a picture worth a few hundred words:

The caption:

Figure 3. Hierarchical structure of a prototypical SIM, [Cs3F]-
[(UO2)(Si4O10)], and the ion exchange process.

The point that the authors make about this kind of material capable of exchanging a naturally occurring essential but slightly[ radioactive element, potassium, and a non-radioactive element, sodium for a radioactive element, cesium (or perhaps another element) is that it accomplishes two tasks simultaneously. I'll put what they say in bold:

SIMs are noteworthy because as “stuffed” porous materials, they may lead to waste forms that simultaneously capture and store multiple radionuclides.

Further they write, indicating that these type of structures are not limited to the one they have pictured in their cartoon immediately above:

The structures can be tuned to accept sets of ions of interest via ion exchange, with an individual structure thus hosting multiple radionuclide waste elements. Furthermore, after the exchange process (performed post-synthesis in an aqueous environment), the entrances may be sealed to isolate the elements. Problematic radionuclides such as cesium and technetium can thus be transformed from volatile species to those of low chemical activity through capture in SIMs, making this potentially another extremely versatile multiradionuclide waste form.

I have more to say about this paper, but at this point, I'd like to do the second thought experiment of this post and talk about my backyard, since we often hear from anti-nukes repetition of the dumb ass clichéd platitude, "Duh...would you like to have "nuclear waste" in your backyard?" This, they apparently believe, passes for wit.

Since I know a lot about so called "nuclear waste," I can definitively answer, "yes," based on the thought experiment I will now suggest, since by doing so, I could improve my health and that of my neighbors by appeal to the same kind of air chemistry I described above for the low capacity - only a million tons per year - of the CO2 capture system I described above.

Suppose authorities came to me and said, "NNadir, you pronuke asshole, we want to put "nuclear waste" in your backyard!"

I’d say, “Sure, as long as I can define, the kind of fission products you can put here, since I’d like to protect myself and my neighbors from health risks.”

Assuming they accept my negotiating stance and allow me to design such a device, here’s what I’d propose and here’s why I’d propose it:

I'd ask them to dig two deep bore holes next to each other, each about half a meter to 1 meter in diameter, with type of cap that would leave them open to the air, this sort of thing:

Since I live in a town in New Jersey with an elevation of about 60 meters above sea level, and thus in order to take advantage of the barometric distribution described above, I might ask that the boreholes be 100 meters deep, so that the lower reaches actually are below sea level. I would ask that the two boreholes have a link drilled between them. At the bottom, a small electric pump to pump out any water that finds its way into the system, which will allow for an option I'll describe below.

As the following graphic shows, New Jersey, the entire state, is sort of a hot spot for ozone pollution:

Source: Tropospheric Ozone Assessment Report: Present-day ozone distribution and trends relevant to human health (Fleming ZL, Doherty RM, von Schneidemesser E, Malley CS, Cooper OR, Pinto JP, et al.. Tropospheric Ozone Assessment Report: Present-day ozone distribution and trends relevant to human health. Elem Sci Anth. 2018;6(1):12.)

The SIM graphic above shows the nanostructure of a so called "nuclear waste" material, but for the macroscopic form, I might ask that the SIM be formed into 50 mm spheres, coated with a specialty ceramic coating containing barium fluoride and titanium dioxide, and that these spheres, and that these spheres be placed in cylindrical containers with free air exchange and placed at the center of one of the bore holes. The air flow would be convective: The so called "nuclear waste" releases heat, heating the air to rise, and the make up cool air comes from the second bore hole, enriched in the air pollutants ozone, nitrous oxide, all of the CFC's and all of the HFC's...etc...maybe some PFOS containing dust.

The difference between the first thought experiment and the second is that in the second case, the system is continuous as opposed to batch: The air that flows into the chamber is always at the highest possible concentration of pollutants, and as it rises to the upper portion, they are all destroyed, particularly if we assure that the humidity in the chamber remains high - which it often is in New Jersey. By contrast, the batch process would involve treating air that was partially cleansed (by containment) by exposure to radiation.

Of course, we can assure that the humidity remains high deliberately; by use of optional approaches. We could, for example, arrange for a film of water to flow down the chamber walls and be pumped out as it reaches the bottom. If the water is in fact a solution of sodium hydroxide – or even better, despite a slightly higher expense, potassium hydroxide, it would not only hydrolyze any residual phosgene derivatives that survive at parts per trillion or parts per quadrillion levels – as opposed to the problematic ozone concentrations of 10’s of parts per billion – and of course, as the case with first thought experiment, carbon dioxide.

I live about a kilometer or two from a light industrial zone. If we located a small nuclear reactor there of a design that is the subject of other thought experiments I conduct, designed to operate at very high temperatures in a fluid phase suitable for distilling cesium (and rubidium and a few other elements) out of the fuel continuously to prevent the buildup of possibly uncontrolled inventories of these elements, a reactor operating at say 10-20 MW(th), we could easily recover this carbon dioxide to make carbon free motor fuels to run the county diesel buses in my area, most of which operate with dangerous diesel fuel and/or dangerous natural gas. This would involve, piping the carbonate solution from the ozone destroying device in my back yard to the reactor, precipitating the carbonate with lime, regenerating the lime with nuclear heat, and hydrogenating the carbon dioxide with nuclear hydrogen to make the wonder fuel dimethyl ether. This system would be entirely carbon neutral, cleaner than the existing system, and infinitely safer than the existing system.

My neighbors, of course, might object, having been bombarded with idiot rhetoric about Fukushima and other highly uneducated selective attention that is destroying our environment but, depending on the distance from my backyard and diffusion rates of the toxic air pollutant ozone, the cost of this system would be offset - perhaps even completely covered - by better health and thus lower health costs connected with the serious waste problem that, by comparison with the trivial problem of so called “nuclear waste.” This would be true whether my neighbors know it or not. Many of us even on the left like to carry on with Ayn Randian bullshit about "cost." Suppose the destruction of ozone in my back yard doesn't cover the financial cost represented by the reduced requirement for health related treatment costs.

Well, I argue, liberal that I am, that moral costs actually matter. It's not all about money. It's about our responsibility to the future. Our refrigerators and the refrigerators in them, our swell Tesla cars, all of our cars, all of us waiting around mindlessly for the grand so called "renewable energy" nirvana that never comes, all of these things have implications for all future generations.

The second (and last) thought experiment out of the way, let me now return to the rest of the paper:

The authors turn to a class of materials that are being widely studied in recent years, metal organic frameworks or "MOFs." They write:

Actinide-Based Metal−Organic Frameworks. The unprecedented modularity and porosity of metal−organic frameworks (MOFs) make them cornerstone materials for a number of emergent applications, including gas storage, separation, sensing, and heterogeneous catalysis.47−51 Yet, another unrealized potential for MOFs lies in the utilization of their unique topologies and tunable pores for development of novel architectures for effective radionuclide sequestration. The potential benefits of MOFs arise from the multiple approaches to actinide (An) integration within the framework structure. One of the main advantages is covalent bond formation, which significantly impedes leaching from the framework. Moreover, more homogeneous distribution of actinides in the structure decreases the accumulation of radiation damage. To date, there are only a few reports covering radionuclide-incorporated frameworks.

Of concern to people who think in terms of "nuclear waste," as opposed to "nuclear resources," are chiefly the elements neptunium (which is part of the only extinct decay chain, the curium-245 decay chain, among the three naturally occurring major actinide decay chains, those originating with, U-238, Th-232, and U-235), americium, (isotope 241, widely used in smoke detectors, is part of the extinct decay chain, isotope 243 is part of the U-235 decay chain), and various isotopes of curium, including the long lived isotope curium-247, an extinct nuclide from which a significant part of the existing planetary inventory of natural U-235 probably derived. These are members of a class of compounds generally referred to as the "minor actinides."

I consider that three isotopes in this class are probably key to vastly reducing the ease of manufacturing nuclear weapons to a ridiculously low level, those being Np-237, Am-214, and Cm-242, the latter being an isotope with a relatively short half life which may be synthesized using Am-241. All of the others, especially since I believe it is critical for humanity to switch to fast neutron nuclear fuel cycles in order to ban energy mining, have use as fuel. However, as we shall see when I turn briefly to the famous tunnel collapse at the Hanford nuclear weapons site, some of these are present in dilute amounts that are nonetheless thought to be problematic.

In terms of MOF's the authors discuss a number of approaches and offer us a nice graphic describing in a general cartoon form, their thinking:

The caption:

Figure 4. A schematic representation of framework modularity for actinide (An) integration on the examples of Zr- and An-based scaffolds. The integrated actinide-containing species are shown in orange and red colors: red and orange spheres represent An-based metal nodes; gray spheres, Zr-based metal nodes; gray solid sticks, organic linkers used for framework synthesis; blue sticks, capping linker; and yellow spheres, An-containing guest species.

Zr here is zirconium. Zirconium is, by the way, a fission product itself.

The authors describe different types of systems for capturing and storing actinides:

Metal Nodes:

The simplest way to prepare actinide containing materials is via direct synthesis, i.e., heating an An salt and an organic linker in a polar solvent such as N,N′-dimethylformamide (DMF). This solvothermal approach commonly used for MOF preparation is advantageous for working with radioactive species mainly due to the moderate temperatures used for An integration, which therefore does not typically lead to the creation of volatile radioactive species, in contrast to the ∼1000 °C temperature regime required for the preparation of radionuclide-containing borosilicate glasses. In general, this synthetic method is used for An immobilization inside the metal nodes of the MOF of interest. Recently, additional synthetic strategies for An integration have been implemented, including metal node extension and postsynthetic cation exchange in which uranium and thorium were integrated into metal nodes.(69) In some cases, two An elements can be integrated through direct synthesis, via processing with two actinide salts and an organic linker...

They give us a nice picture of some "organic linkers:"

The caption:

Figure 5. Actinide integration through coordination of radionuclides to the specific linker anchors.

These "anchors" are designed to capture as well as store actinides, and thus are useful for dilute sources.

I'm particularly enamored of the central structure in this picture, which has a melamine core, since it contains a lot of nitrogens. This summer my son went to Europe to gain exposure to a relatively new area in materials science, polymer derived ceramics. Melamines are multifunctional compounds demonstrating symmetry (D3h) and thus are suitable for polymerization. An important class of ceramics are the nitrides, and given what I've learned of the area in which my son's research will be, it occurs to me that this class of compounds offers some special opportunities for the incorporation of radionuclides into structures useful for things like my thought experiments, as well as for the recovery of actinides from dilute sources.

Speaking of dilute sources of actinides, I'd like to turn briefly to the Hanford facility, where the availability of this kind of actinide capturing species might have prevented an event there that garnered some negative and typically paranoid attention. (I learned of this event right here at DU from an antinuke who made it to my happy and wonderful ignore list, the worst kind of anti-nuke, the sort of liar who says "I'm not against nuclear power but..." where the "but" is followed by some specious bull focusing on some triviality that is nowhere near as important as the observed collapse of our planetary atmosphere that has lead to growing deaths from heat waves and the destruction of huge areas of ecosystems by intractable fires. Antinukes are a trivializing bunch.)

In 1964, some chemical reactors used in processing reactor fuel in order to extract weapons grade plutonium for nuclear weapons, were loaded on to nine rail cars. At the time, it was thought that the chemical reactors were "too radioactive" to ship anywhere, so the administration at the time decided to build a tunnel, a Quonset hut derived tunnel, supported by wooden beams, and push the rail cars into it. Then nobody thought very much about these old reactors, and they remained there more or less forgotten until 2017 when, the wooden support beams having rotted from rain or whatever, the tunnel collapsed, generating all sorts of news reports all over the world, apparently.

I have been unable to learn what radioactive species in the chemical reactors caused the people in 1964 so much concern, but subsequent the tunnel has been filled with grout, and probably monitored for sometime and forgotten. Now, if the radioactive nuclide that made the reactors "too radioactive" in 1964, was cesium-137, in 2018, the reactors are only 28% as radioactive as they were then. More likely though, the reactors were contaminated with actinides, probably plutonium. A problem in historic plutonium separations using either the bismuth phosphate process or the still utilized (but probably needing to be replaced) Purex process is that plutonium (IV) oxide can under the right circumstances for an insoluble polymeric form that is very difficult to dissolve. The existence of this polymer is great if one is seeking to prevent plutonium migration, but on the other hand it's a problem if you're trying to isolate plutonium to reduce to the metal to make a nuclear weapon. One option is to subject the plutonium to a very powerful oxidant to oxidize it to soluble plutonium VI compounds, but of course such an oxidant might also dissolve the chemical reactor if the reactor has not be designed to handle such materials.

In 1964, no one knew about MOF's with "linker anchors" but had they, they might have chosen to cut the reactors up, dissolve them in a powerful oxidant, whereupon any actinides would be present in dilute solution, pass them over a selective MOF, capture the actinides, (and anything else of interest). There would have then been no tunnel, and no collapse and no problem. Of course the fact that people were able to completely forget about the tunnel suggests that it wasn't a huge risk in the first place. It's not like thousands of people were dropping dead because it was there, and thus it was possible to not notice it.

It is, by contrast, almost impossible to not notice that the State of California is on fire and that people are dropping dead from heat waves, even it is has long been possible to ignore that while airheads carry on about tunnels at Hanford, seven million people die every year from air pollution.

A collapsed tunnel at Hanford doesn’t matter; climate change does.

A little more from the paper:


The MOF “classical” applications including gas storage and separation are based on utilization of their main property—intrinsic porosity. This phenomenal porosity is also a key factor for efficient capture of radionuclide-containing species with further sealing of An-containing guests inside the cavity through installation of additional linkers as pore caps (described above). For instance, MOF porosity and modularity could potentially solve current concerns in nuclear waste management associated with capture and sequestration of highly volatile gases produced from nuclear fission (e.g., iodine) or pertechnetate species.(78−80)

However, efficient utilization of nanoporous materials to capture volatile radionuclide species requires mechanistic studies of adsorption/desorption kinetics, as well as development of synthetic routes for modification of pore microenvironment to enhance iodine-binding affinity.(81) The incorporation of guest species inside a porous framework can be achieved not only by a diffusion route but also through an ion-exchange process.(82) Thus, due to the high surface area and low structural density, these materials can potentially contain a significant An content.

Since the design space for actinide MOFs is virtually unlimited, the utilization of theoretical/computational methods is necessary to accelerate the development of novel, potentially stable MOF architectures. As an example, online databases of MOF structures could be used to sample representative potential host structures, and those energetically favorable to incorporate a radionuclide could be identified. Thus, we believe that synergy between experiment and theory/modeling are necessary to delineate the energetically favorable actinide-containing structural motifs, thereby allowing the identification of further MOF candidates as bases for improved nuclear waste forms. Efforts to use electronic structure calculations in identifying MOF structures for sequestering radionuclides are being pursued...

And some remarks on another system useful for sequestering cesium, the "Prussian blue analogues" in porous silica:

Porous Silica with Multiple Scales of Porosity for Capturing Radionuclides
Nuclear waste management generally overlooks the step between the synthesis process of a specific waste form structure and the actual waste (liquid or gaseous). Indeed, an extraction step, from the liquid or gaseous waste, is needed to obtain an initial flow that can be used directly as raw material for a specific containment matrix. In this context, the concept of a porous silica or glass-based material with the dual function of entrapment and confinement was developed within a hierarchical material approach. Research is thus being conducted to assemble a robust confinement vehicle using monolithic supports with a continuous three-dimensional multiscale porous structure to house the nanoparticles. The main properties desired of these hierarchical materials include (a) the ability to extract the targeted radionuclide from diverse liquid nuclear waste (different pH, different salinity...) or from gaseous waste streams, in cases of volatile radionuclides such as iodine; (b) a high capacity and selectivity in order to minimize the volume of the final waste form; (c) long-term resistance to both radiation and chemical damage; and (d) an optimized porous structure for high capacity and efficient extraction.

A number of materials have been developed to selectively extract radionuclides from different liquid waste streams, focusing primarily on volatile and hazardous radionuclides such as Cs, Sr, and I.(84) Among these, ferrocyanide compounds were shown to be excellent candidates for Cs entrapment,(85) while zeolitic structures can readily entrap Sr and, to a lesser extent, Cs,(86,87) and silver-nitrate phases for iodine species.(88) All of these bulk materials are extremely efficient for the selective extraction of the targeted materials; however, the significant challenge for these is low loading in the final waste form...

...One remedy is to utilize the entire volume of the adsorbent by using nanoparticles that effectively provide 100% exterior surface, thereby not only reducing the overall volume of the waste form but also improving the kinetics of absorption.(90) As shown in Figure 6a, the micrometer-sized PBA particles are able to entrap about 0.75 mmol of Cs per gram of PBA, whereas the nanosized particles have a capacity of 1.2 mmol of Cs per gram of PBA. Furthermore, these nanosized PBA particles greatly reduce the time it takes to extract Cs (Figure 6b).

The utilization of loose nanoparticle-based materials by themselves is, for obvious safety reasons, not an acceptable approach for either extraction or confinement, and thus, the creation of a hierarchical structure consisting of a monolithic support in which the nanoparticles are bound and confined is being pursued. Specifically, research is being conducted to assemble continuous three-dimensional multiscale porous structures to house the nanoparticles, similar to the approach for catalytic materials.(91) Nanoparticles can be grafted to the inside of such monoliths, securing the nanoparticle but retaining the ability to efficiently and selectively entrap the targeted radionuclides. Once the radionuclides are absorbed, the pores can be sealed to create a robust containment matrix in a hierarchical waste form...

Figure 6b:

Its caption:

Figure 6. Cs extraction using Prussian-Blue Analogous (PBA) adsorbent inserted into a inorganic support. Effect of the size of PBA and of the porosity of the support. (a) “Nanosize” corresponds to KCu-PBA nanoparticles inserted into silica materials,(95,111) and bulk corresponds to micrometer-sized KCu-PBA.(94) (b) Mesoporous support corresponds to KCu-PBA nanoparticles inserted into silica materials and dense support to KNi-PBA loaded into a dense zirconia matrix.(112)

There's a few more interesting remarks in the paper and a couple more cool pictures, but let's cut it here.

While my most recent favorite dumb ass anti-nuke comment is the one about the Hanford tunnel, I of course, have had a wonderful opportunity to hear thousands upon thousands of them over the years, most of them "renewable" horse manure about how Fukushima and Chernobyl are the only energy related disasters we should think about; nothing else matters nearly as much.

Of course, a pretty common one I get here is when some illiterate anti-nuke chimes into to say "Nobody reads anything written by that asshole NNadir...." or something along those lines. Besides being poorly educated, apparently their are some anti-nukes who are a bit solipsistic inasmuch as they assume they speak for "everyone."

Of course, I doubt that many people actually do care to read this stuff, but my purpose in writing this post was as much to clarify my own thinking as it was to hope that someone might read and value the content. It was to teach myself, which I regard as my primary responsibility, even as my life approaches its end.

We live in the TWITter age, where twits live and die by "tweets." There is little use these days, more than ever, for deep reflection.

And speaking of twits:

Anti-nukes bet the future of humanity on so called "renewable energy." It didn't work; it isn't working; it won't work.

What is telling, besides their selective attention, is that they were disinterested in banning fossil fuels - their bullshit redundant systems depend on access to and use of dangerous natural gas, this in a particularly wasteful fashion - but were interested in attacking nuclear energy, an activity in which - unlike whatever small interest they may have had in saving the environment - they've been successful, at the expense of all future generations.

This summer of a burning planet should demonstrate even to the impossibly stupid community of anti-nukes who prattle on endlessly with their “by 2100” or “by 2050” or “by 2080,” garbage empty promises by which they excuse their enormous contempt for future generations. Climate change is not "by 2100." It is now.

It is now apparent that we must find a way to remove the carbon dioxide already dumped, never mind stop dumping it, an incomprehensibly large engineering challenge that will require massive amounts of energy, sustainable energy.

There is one, and only one form of energy that is concentrated enough and sustainable enough to do the job. It's nuclear energy.

Have a pleasant Sunday evening.

Klansman in Chief Looks Like the Fat Particles in his Fat Head Are About to Explode.

I can only watch the racist nincompoop with the sound off, but I'm enjoying the football players telling him and his fellow klansmen to go to hell.

NFL players kneel, raise fists or sit out National Anthem as preseason gets in full swing

(I just came back from watching BlackKKKlansman, and it makes it exactly clear what this useless parasite pig is.)

If the pariah split a vein open and bled to death in his own vomit in one of his tirades, no one with a brain would mourn his useless and worthless life...

Ken Seddon died this year.

I'm sure that for many people, the overwhelming majority of people on the planet, this man, Ken Seddon, is obscure and without meaning, but he was the sort of man on whom the world depends, more than most people know, a scientist with extreme passion.

Recently, going through a back issue of the scientific journal Green Chemistry, I came across his obituary:

Obituary: Kenneth R. Seddon: 1950–2018

An excerpt:

Prof. Ken Seddon died on 21 Jan 2018 and the green chemistry community has lost one truly original character. Ken was in many ways a larger than life figure and the image he cultivated was one designed to elicit a reaction. Like the ionic liquids he devoted much of his career to, this often resulted in polarisation into positives and negatives. He could be in equal measure, generous, supportive, challenging, and yet also dismissive, quick to judge and then as immovable as a rock. Amongst those of us around the world who counted him as a colleague, supervisor, mentor, or collaborator though, he evoked deep-seated loyalty and friendship. He could be gracious, charming and thoroughly inclusive and had an infectious enthusiasm for science.
Let's consider just what it was that Ken achieved. He published over 400 papers with 44 of these in Green Chemistry, starting with one in the very first issue (Diels–Alder reactions in ionic liquids. A safe recyclable alternative to lithium perchlorate–diethyl ether mixtures, Green Chem., 1999, 1, 23–25). In 2011, he found himself as the highest ranked UK chemist in the Times Higher Education ‘Top chemists of the past decade’ survey, and was awarded an OBE in 2015 for his services to chemistry.

But let's be clear, Ken did not invent ionic liquids, and he never claimed to have! He was not even the first to make use of ionic liquids in electrochemistry, synthesis, catalysis, or as new solvents.

What he did do, and he did this remarkably well, was to recognise that there was a need to unify the disparate niche research areas where ionic liquids were under investigation and to create a broader new research landscape. As such, his greatest impact on science, and on green chemistry in particular, is through the popularisation of the idea that ionic liquids might actually be interesting and useful liquids to study – indeed, that they might be ‘neoteric solutions’.

Perhaps the most important "ionic liquid" is the one in your brain - whether you know it or not - the neurotransmitter acetylcholine, which has this structure:

Ionic liquids are salts, generally of a positively charged organic molecule and a negative charged molecule, also often organic. There are, in theory, an infinite number of them. Here's an example of one, utilized as a catalyst for the preparation of biodiesel apparently:

I met Ken Seddon once, when he gave a lecture at a company where I worked; we had some interest in the commercial synthesis of imidazoles, important building blocks of a class of ionic liquids, alkyl imidazolium salts. I actually didn't stay with that company very much longer, and in my career, ionic liquids didn't play all that much of a role. But I remember his talk, and his passion, that he carried right through lunch at a little restaurant besides a beautiful harbor in Massachusetts.

But nevertheless, in the light of his passion, I began to follow that chemistry, and it does seem to me that compounds of this type might well be extremely useful to save what's left of the world we are so hellbent on destroying. Learning about ionic liquids changed my life.

In Google Scholar, as of this morning, there are nearly half a million hits for the topic "ionic liquids."

This man had a lot to do with the scientific popularity of this set of molecules. Even if few people know who he was, he was important, and a valuable citizen of the world.

The Laos disaster reminds us that local people are too often victims of dam development

On July 22, the Xepian-Xe Nam Noy hydropower dam under construction in Laos’ Attapeu Province collapsed. Flash flooding inundated eight villages, killing at least 29 people and leaving 131 officially reported missing. The final number of casualties could be much higher.

Disaster response activities are ongoing. The deputy secretary of the province claimed that more than 1,100 people were still unaccounted for, as of July 27. Laotian authorities are investigating whether the collapse was caused by heavy rainfall, inadequate construction standards, or a combination of the two...

...On July 22, the Xepian-Xe Nam Noy hydropower dam under construction in Laos’ Attapeu Province collapsed. Flash flooding inundated eight villages, killing at least 29 people and leaving 131 officially reported missing. The final number of casualties could be much higher.

Disaster response activities are ongoing. The deputy secretary of the province claimed that more than 1,100 people were still unaccounted for, as of July 27. Laotian authorities are investigating whether the collapse was caused by heavy rainfall, inadequate construction standards, or a combination of the two...

The Laos disaster reminds us that local people are too often victims of dam development

Don't worry; be happy. Despite the tremendous triumph of "green" energy that we all hear all about all the time, climate change seems more real than ever, and that should help us be done with those nasty rivers once and for all.

How a moral philospher justifies his carbon footprint.

I recently flew to Florida to visit family. My round-trip economy seat emitted roughly two tonnes of carbon dioxide, according to one carbon offsetting website. By contrast, the average person in Britain is responsible for roughly seven tonnes for the entire year, already quite high by global standards.

This makes me a climate change villain. Dumping such huge amounts of carbon into the atmosphere seems clearly morally wrong, because of the harm this will cause others. But carbon offsets let me fly with a clear conscience – for now.

When I buy an offset, carbon emissions are reduced elsewhere, cancelling out those from my flight. It might involve planting or preserving trees, or installing cheap and efficient stoves. Offsetting my Florida trip cost £13 – a couple of drinks in the departures lounge.

Convenient. But perhaps too easy? Offsetting clearly raises the scientific question of whether a purchase will really reduce global carbon emissions. This is difficult and controversial stuff, better suited to climate scientists and economists.

Philosophers, by contrast, deal in hypotheticals...

How A Moral Philosopher Justifies His Carbon Footprint.
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