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I saw "The Death of Stalin" last night.

Being familiar with the history of this event, and kind of curious about it since I couldn't imagine how someone could rearrange the end of the horror of Stalinism into a comedy I went to see the movie The Death of Stalin last night by myself, as both my wife and my son at home are working like crazy on their intellectual pursuits.

I couldn't imagine I would laugh, but laugh I did. It was hysterically absurd.

Steve Buscemi, playing Khruschev - who in real life was actually a crude and uneducated, if highly intelligent man - steals the show. He plays Khruschev sort of the way he played the Carl Showalter in Fargo, although also adding a level of something quite different.

I have always hated the real life Beria, a rapist, torturer and murderer, and Simon Beale does a pretty good job portraying this awful man, although his physical resemblance is not quite that strong to the real Beria, who had a thin and almost intellectual look, although he was one of history's greatest beasts.

Michael Palin is wonderful as Molotov as well.

If you are interested at all in the tawdry history of Stalinism, as well as possessed of a somewhat offbeat sense of humor, don't miss it.

A Minor Problem With Visible Light Up-conversion to UV for Pollutant Destruction: It's a Myth.

Since the mid-20th century, a large amounts of seriously recalcitrant organic pollutants - most often organohalides - have been accumulating, sometimes at dangerous levels, particularly in the tissue of animals high in the food chain, including but not limited to human beings. One can read lots of papers about these molecules in breast milk (and the milk of other species) for example.

The long term persistence of these molecules is related to the strength of the chemical bonds that define them, and these in turn are defined, in quantum mechanical terms by a set of molecular orbitals, most often characterized mathematically as three dimensional wave functions. In quantum mechanics, the transition from one state (represented by its wave function) to another state (represented by a different wave function) requires a certain minimal energy, to wit: It is not possible for a large number of energy packets (quanta of light) to break a bond whose energy transition exceeds the energy associated with its wavelength/frequency.

The energy of light is of course, described by the famous Planck equation, which most people who take science courses encounter in high school, or in the worst case, early in their college careers:

An unfortunate feature of our times, wherever environmental issues are discussed, is sun worship - an enthusiasm for all things "solar" - that may hark back to some ancient religious fervor, I don't know, as I'm not a participant.

Scientists are not magical beings separate from humanity; they are pretty much like everyone else, and as such they can get caught up in popular fads, and run with ideas that prove to be nonsensical. Some years back, stuck in some airport somewhere and bored out of my mind with nothing to read, I came across a delightful little book all about these kinds of adventures in scientists kidding themselves, this one: Yes, We Have No Neutrons: An Eye-Opening Tour through the Twists and Turns of Bad Science. It's all about "Cold Fusion," "IQ testing" "N-rays" etc, etc, etc...

A fun read, take it as you will...

By the way, bad science does not always involve bad scientists. Highly intelligent and highly competent people can often mislead themselves terribly. Martin Fleischmann of "Cold Fusion" fame was throughout his career highly regarded as an electrochemist, the author of more than 250 scientific papers, which is why when he erroneously reported "cold fusion" he was taken - initially at least - seriously.

To return to the point of recalcitrant pollutants, it should be pretty clear that since they often appear in surface waters - the Hudson River has long been polluted with polychlorobiphenyls (PCBs) - solar energy doesn't do a very good job at decomposing them. If it did, they would tend to disappear, at least on sunny days in summer.

They, um, don't.

This is because visible light, although it is sufficiently energetic to break some chemical bonds - notably the hydrogen-oxygen bond in water, which is, of course, how photosynthesis works - is insufficiently energetic to break the (aromatic) carbon chlorine bond in a PCB.

At a minimum, higher frequency radiation is required to break these bonds, at a minimum short wavelength ultraviolet radiation, although x-rays and gamma rays are even better. Now even though humanity is working hard at destroying the ozone layer which absorbs and degrades UV radiation, it's a good thing that we can't have "solar remediation" of PCB's, since energy at the wavelength that destroys them would also destroy many of the molecules in our flesh; a fact that is connected with the ever rising rates of melanoma, a largely still incurable cancer that is involved in primitive or more sophisticated sun worship.

However the culture of enthusiasm of all things solar so much as it appears in science has lead many people to speculate that it is possible to "upconvert" visible wavelengths of light into UV light which is known to work, particularly in the presence of titanium dioxide catalysts to degrade recalcitrant pollutants.

I am hardly an expert in the theory of this stuff, by the way. In fact the first time I heard of it is in the paper from the primary scientific literature written by scientists at Yale and Clemson, that I will now discuss, which claims, that the whole affair is, in fact, a myth: The Myth of Visible Light Photocatalysis Using Lanthanide Upconversion Materials. (Cates et al, Environ. Sci. Technol., 2018, 52 (5), pp 2973–2980)

From the introduction, which covers the very real basics about titanium dioxide catalysts and the mechanism of their actions, and a brief summary of the controversy:

Heterogeneous photocatalysis has maintained a strong foothold in water treatment technology research since the explosion of studies involving TiO2 began in the 1990s. Among the many uses of semiconductor photocatalysts proposed by academia in the environmental fields, advanced oxidation is the most common; therein, production of hydroxyl radicals by catalyst suspensions in photoreactors is seen as a “chemical free” alternative to H2O2 and O3-based unit processes for destruction of recalcitrant water contaminants.1,2 While the most effective photocatalytic materials have band gap energies (Eg) that demand UV-range excitation wavelengths, many groups have pursued catalysts that are activated instead by lower-energy visible light.3−6 These efforts are motivated by the prospect of replacing energy-intensive UV lamp reactors with solar reactors, though the operational practicality of this concept has been debated.7 The primary route to visible light activation of semiconductors is through the use of materials with sufficiently low Eg or intraband states to absorb such light and promote valence electrons into the conduction band. Inherently, however, a lower Eg generally implies weaker redox potential of the resulting conduction band electrons (e− cb), valence band holes (h+ vb), or both.8

Here's a picture of the proposed mechanism that people reporting "upconversion" claim:

The caption:

Figure 1. Mechanism of visible-to-UV upconversion sensitized photocatalysis disputed herein. Green circle, UC phosphor particle; white circles, semiconductor photocatalyst particles.

In the paper the authors describe the synthesis of some of these putative upconversion catalysts and their characterization and the proposed mechanism under which they work.

The authors discuss the mechanism of upconversion, which by the way is according to them, as I understand it, a known phenomenon, but one which has very limited intensity:

The caption:

Figure 2. (A) Mechanisms of visible-to-UVC conversion by YSO: Pr3+.(16,17) (B) Primary mechanism of visible-to-UV conversion by Er3+-doped phosphors.(35) (C) Upconversion emission spectra of phosphors under 488 nm laser excitation (140 mW); inset shows YAG:Er3+ and undoped YAG spectra with adjusted axes. The peaks seen at >430 nm are due to leakage of the excitation light from the monochromator.

Anyway, they make the catalysts and then test them against a series of well known persistent organic pollutants, dyes used in the preparation of clothing.

Figure 4. (A) Decoloration of MB by phosphor-TiO2 composites under 488 nm laser irradiation. (B) MB decoloration by composites and controls under white LED irradiation. (C) Degradation of various dyes by composite materials under white LED irradiation for 240 min; solid and striped bars depict Ln3+-doped and undoped phosphor materials, respectively. (D) Degradation of phenol under white LED irradiation. Error bars denote standard deviations of experiments performed in triplicate.

They compare these unimpressive results with actual direct irradiation of "MB" methylene blue with UV radiation not resulting from "upconversion:"

Figure 5. Effect of isopropanol •OH scavenging on photocatalytic degradation of MB by YSO: Pr3+/TiO2 composite particles under W-LED (visible) and UVA irradiation. Error bars indicate standard deviations of triplicate experiments.

In their discussion the authors write:

Above we have shown that UV UC is not responsible for enhanced dye degradation rates by phosphor/TiO2 composite materials; however, our experiments did indicate that the presence of the YAG:Er3+, YSO : Pr3+, or undoped host enhanced dye degradation rates by phosphor/TiO2 composite materials; however, our experiments did indicate that the presence of the YAG : Er3+, YSO : Pr3+, or undoped host components may result in statistically significant MB degradation enhancements compared to TiO2 alone. This is enhancement is only observed when the system is excited within the MB absorption range, and it does not require absorption by the Ln3+/dielectric component. Control experiments using simple, unfused mixtures of phosphor and TiO2 particles resulted in no enhancement (SI Figure S7), thus clearly indicating that the presence of epitaxial YSO/YAG− TiO2 interface is required for the catalytic effect.

They offer some reasons for why they think that many of the papers on this subject are not reproducible or valid:

In our opinion, the overwhelming majoring of UC-PC literature exhibits three critical experimental flaws: first, the syntheses and quality of the UC materials are highly questionable, typically using low purity stock chemicals and showing XRD patterns that indicate phase impurities (e.g., see ref 21, Figure 1a and b therein). It is well-known that optical propertiesespecially in UC materialsare highly affected by certain transition metal impurities, necessitating the use of 99.99% purity or greater stock chemicals.50 Second, in order to conclude that UC is responsible for the catalytic enhancements, the use of the nonactivated phosphor host material (e.g., undoped YAP or YAG) in control experiments is required in order to confirm that opticaland not chemicaleffects are responsible. Only the study by Feng et al. included such a control, finding that their YAG:Er3+ sample enhanced MB degradation to a greater extent than YAG under white fluorescent lamp excitation (∼12% vs ∼8% degradation after 2 h), though both performed better than TiO2-only (∼5% degradation).10

Finally, UC-PC authors rarely include UC emission spectra of the materials in their publications, which is certainly a minimum requirement for demonstrating UC capability prior to applying this phenomena to environmental technology. Studies unrelated to photocatalysis have shown visible-to-UV conversion by the same aforementioned Er3+-doped systems, though they used single crystals under pulse laser excitation with sophisticated detection systems.35−37,51 Furthermore, the UC spectrum of YSO: Pr3+ provided by Wu et al., as well as one in a more recent YSO: Pr3+ UC-PC paper, were measured with fluorescence spectrometers equipped with a xenon lamps.22,52 Based on our experience in characterizing YSO: Pr3+, cyan or blue laser excitation in excess of 50 mW and phase-sensitive detection are required to resolve the visible-to-UV anti-Stokes emission spectrum.13,26 Their spectra instead appear to be normal Stokes emission that resulted from unintentional UV excitation of the sample by second order diffraction from the source monochromator in the absence of appropriate long-pass filters. This same instrumental blunder has been implicated in false reports of UC by carbon quantum dots,53 and illustrates the importance of avoiding accidental UV excitation when attempting to measure upconverted visible light.

Too bad. One kind of wishes it worked. We could just dump titanium oxide doped with lanthanides in the Hudson River and be done with it, but we won't done with it.

Right now the PCB contaminated riverbed of the Hudson River is being dredged, but the real problem is that this is just moving a pollutant from one place to another: There is no safe place to dispose of the dredged soils really.

Speaking of another "solar will save us" degradation, the degradation of the planetary atmosphere, the vast "solar revolution" has been notoriously ineffective on that score as well. The Mauna Loa observatory seemed to be off line for a few days - I thought Trump and Pruitt had defunded it in my less than inappropriate paranoia, but it came back on line. The reported concentration on April 21, 2018 was 411.14 ppm which is, to my knowledge, the highest value ever measured there.

Be that as it may, we seem to be falling asleep worshiping the sun.

Metaphors aside, don't do it yourself. Melanoma is a tough disease: I lost two good friends to it.

Have a pleasant Sunday.

I have a good friend whose name is Michael Cohen.

Wonderful guy, very intelligent, very liberal, a good and supportive friend, but I haven't been in touch with him for a few years.

I called him up this week to make fun of him and his name.

Those of us who have common names that are shared with famous people take a certain amount of crap about it. I've had it my whole life, and it was nice to kid him about it.

Of course, as I know full well, people making jokes about you sharing a name with a famous person always think they're being original and funny and of course, you've heard those jokes 10,000 times, and I'm sure he's going through that, but having been a victim myself, I just couldn't restrain myself.

I try to have a good nature about it, and so did he.

At least the person(s) with whom I share a name aren't going to prison for helping a racist criminal into the White House.

If this state of affairs is a tragedy for our country and the world, a small silver lining for me was to connect with an old friend with whom I needed to be in touch.

Michael Burlingame on Lincoln's Relationship to African Americans.

An interesting lecture by Historian Michael Burlingame, a prominent Lincoln Expert.

In a time where official government racism is regrettably ascendant, it is a remarkable exposition with considerable research and evidence showing a President moving well beyond his country and his times in favor of human decency.

CSPAN History African Americans and Abraham Lincoln

The remarks on why Lincoln died, and the reference placing him in the company of more modern Americans of the 20th century would alone make it worth watching.

Chinese scientists demonstrate complete mineralization of the persistent pollutant PFOA.

Recently in this space, we learned about the pollution of wells, fish in a Michigan unincorporated area:

200 Homes In Oscoda, MI Using Bottled Water; PFAS From Closed Airbase In Wells, Lake Huron, Fish

PFAS is a broad chemical class of compounds and is an abbreviation for "perfluoroalkylated substances."

Since the US EPA has been effectively shut down to serve the interests of a corrupt member of the Trump crime family, who squanders money on first class flights for himself and his friends in order to prevent it being spent on the Environment, it is necessary to refer to a document from a European agency, in this case the European Food Safety Authority, to give a comprehensive description of what these compounds are, and something about their health implications: Perfluoroalkylated substances in food: occurrence and dietary exposure

One may find a list of the compounds in this document.

The report, which is a report in meta-analysis of a wide variety of published data, assembles data from studies involving over 50,000 samples, and concludes that most concentrations in food stuffs in Europe are below actionable limits, the "TDI" or "Tolerable Daily Intake" but are nonetheless clearly detectable in pretty much everything. The data evaluated was collected over six years from 2006 to 2012.

The compounds do accumulate in tissue, particularly adipose tissue, and they do not degrade in tissue, nor are they generally excreted.

Although the report indicates that the problem is not yet represent a major health risk from the foodstuffs analyzed, it does list the toxicological and human health concern after stating the sources of these pollutants:

Public health concern towards PFASs was raised after several studies indicated that PFOS and PFOA are present in the environment including the human body. Several adverse health effects e.g. hepatotoxicity, developmental toxicity, neurobehavioral toxicity, immunotoxicity, reproductive toxicity, lung toxicity, hormonal effects, as well as a weak genotoxic and carcinogenic potential have been demonstrated in experimental studies in animals (Lau et al., 2007; Zhang et al., 2008; Shi et al., 2009; Peden-Adams et al., 2009; Eriksen et al., 2010; Pinkas et al., 2010). Recently, an epidemiological study performed on a children cohort in the Faroe Islands indicated that high exposure to PFASs was associated with reduced humoral immune response to immunisations in children (Grandjean et al., 2012). Many studies have reported the presence of PFASs in food indicating fish and other seafood as the most contaminated commodities (Berger et al., 2009; Delinsky et al., 2009; Haug et al. 2010a; Schuetze et al., 2010)...

In the general scientific literature the most commonly mentioned PFAS that I see are PFOS and PFOA, respectively perfluorooctanoic sulfonic acid and perfluorooctanoic acid.

The paper I will site below referring to the title here - happily it is open access - refers to the latter compound.

If you're wondering by the way, where these compounds come from, they were widely used in a wide range of consumer products and materials, one of the most famous of such compounds was the now reformulated (and not necessarily harmless) product Scotch Guard, which keeps your furniture stain free. (Aren't you lucky?)

When reading the post above about the unfortunate Oscoda region, in a response I proposed to write about an interesting paper I came across in my general reading about a new kind of laser material for putting out short wavelength (high energy) UV radiation at wavelengths that have been shown to degrade PFOA, albeit slowly, UV radiation at 185 nanometers. This material was said to lase at wavelengths at 177 nm, and therefore should work. This paper is here:

CsSiB3O7: A Beryllium-Free Deep-Ultraviolet Nonlinear Optical Material Discovered by the Combination of Electron Diffraction and First-Principles Calculations (Sun et al, Chem. Mater., 2018, 30 (7), pp 2203–2207)

As interesting as this paper is, it appears that this material is still a laboratory curiosity, an impurity discovered in a similar compound, a single mm scale crystal does not appear to have been grown, so with dreams of beryllium free UV lasers aside for now, I did a quick search to see the latest and greatest path to actually remediating this worldwide environmental problem via radiation, radiation being the only tool for degrading PFAS that will work.

So, I won't be discussing this interesting paper on this website any further.

You may not like that bolded statement, an inconvenient truth if you will, but having just returned from my local "March for Science" nominally dedicated to "facts" and having heard a pompous airhead from the Sierra Club having no facts to support his absurd argument, I'm trying to still believe that facts matter, whether people who hate them are nominally either on the left or the right.

Ignorance from the leadership of the leadership of putative self declared "Environmental Organizations" is no less toxic than ignorance on the far right. Sorry but it's true. Your Sierra Club calendar at Christmas may not be helping to address environmental problems; it may be hurting.

The paper I found is this one: Complete mineralization of perfluorooctanoic acid (PFOA) by γ-irradiation in aqueous solution (Sheng et al, Scientific Reports volume 4, Article number: 7418 (2014))

Although the paper is open sourced and you can read it yourself at the link, I'll take the liberty of reproducing the opening paragraphs here:

A class of fully fluorinated hydrocarbons known as perfluorocarboxylic acids (PFCAs, CnF2n + 1COOH) has been widely applied in various ranges for several decades. They are receiving increasing attention because of their easy bioaccumulation and persistent toxic environment impact. Perfluorooctanoic acid (C7F15COOH, PFOA), as a PFCA has already been detected in environment waters, human bodies and wildlife1,2,3,4. As a ubiquitous environmental contaminant, PFOA has the following features: extremely resistant degradation, bioaccumulation in food chains, and long half-lives in human bodies, all of which present characteristics of persistent organic pollutants5,6. The major human exposure sources to PFOA and other PFCs include drinking water7 and edible fish8 etc, and can lead to several chronic and developmental problems, such as children attention deficit/hyperactivity disorder9 and lowered immune response to vaccinations10. Statistic survey shows that its concentration in human bodies and wildlife continues to increase in certain location globally11.

However, PFOA is very stable and considered almost non-biodegradable under natural environments because of the strong C-F bonds (116 kcal/mol). Besides, some researchers reported that PFCAs could almost not be degraded by advanced oxidation process. The principal reason may be that C-F bonds can't be destroyed effectively by hydroxyl radicals (·OH)12,13. Various treatments for PFCAs including adsorption14, photocatalysis15,16, photolysis17, thermolysis18, sonochemical19 and other methods20,21 have been tested for decomposing PFCAs. However, harsh reaction conditions at high temperatures and high pressures are usually needed18,19. Furthermore, the mineralization and defluorination of PFCAs always could not be achieved completely, and toxic by-products might be formed during the decomposing processes12. Thus, it is highly desirable not only to decompose the PFCAs, but also to defluorinate the toxic by-products for complete mineralization of PFCAs. A novel method for PFCAs mineralization with high efficiency is still highly desired.

...highly desired indeed.

They have such a method, and its described in the paper, which again you can read without traveling to a science library.

Here's a relevant graphic from the paper:

The best pathway involves basic solutions, so it's not a slam dunk direct drinking water approach, although it is very easy to remove calcium hydroxide from water simply by bubbling air through it, especially now since our air is so enriched in the dangerous fossil fuel waste carbon dioxide. Calcium hydroxide would be preferred since calcium fluoride, a component of many dental preparations, is completely insoluble, thus negating any effects from either hydrogen fluoride or soluble fluoride salts.

But it works apparently.

In this paper, the source of γ radiation was cobalt-60. My personally preferred source of γ radiation is cesium-137, which is readily available from used nuclear fuel, and in fact is available to USDOE licensees from stock, as I noted in a previous post in this space.

16 Years of (Radioactive) Cesium Recovery Processing at Hanford's B Plant.

The Ba-137m gamma ray available from the decay of cesium-137 is only about half as energetic as the Co-60 gamma ray, but it is well known to produce solvated electrons, which according to this paper on PFOA degradation is the key intermediate.

The degradation pathway, which is something along the lines I imagined, but also slighly different, is also shown:

This shows that the pathway is sequential and takes place at the functionalized end of these molecules. It is entirely possible that other pathways, removing fluorine atoms on the interior chain might have a toxicological footprint that is worse - possibly, but not definitively - and so the shown mechanism is to be preferred, since these intermediate perfluoro shorter chained alkanoic acids are already in the environment, some still in commercial products. Thus stopping the radiation process before completion is not likely to make things worse as opposed to better.

Nevertheless, with enough exposure, they will definitely entirely degrade these compounds to carbon dioxide and calcium fluoride, the mineral fluorite.

Have a nice Saturday evening.

16 Years of (Radioactive) Cesium Recovery Processing at Hanford's B Plant.

If you want to get a rise out of people with a modicum of understanding of environmental issues, and certain primitive ideas about it, one can mention the Hanford "Nuclear Waste" tanks on the Hanford Reservation, the location of the Pacific Northwest National Laboratories.

This plant was the site of production for the majority of the plutonium used in the production of the American Nuclear Weapons arsenal, an arsenal that I personally believe to need that "swords into ploughshares" approach. Operations began there in the early 1940's, and plutonium production at the site continued until 1987, when the N-reactor - a nuclear reactor with a basic design similar to the Chernobyl reactor, although unlike Chernobyl reactor the N reactor featured a negative void coefficient - was shut and the United States announced it had all the plutonium it would ever need.

(This, by the way, in my opinion, is an incorrect statement. My view is that we need more plutonium, not less of it, the idea behind this view being to ban most mining for energy for several centuries, until some future generation, unlike ours, gets it head on straight. Converted to plutonium, the uranium (and thorium) already mined and isolated could supply all of humanity's energy needs for centuries, but no matter.)

Understandably, since almost everything about the "new" element, plutonium, was unknown - even though some of the best minds in the United States (and elsewhere) were studying it - the chemical processing of plutonium was more or less ad hoc, conducted on the fly, without much long term environmental thinking, or, in fact, much long term thinking about anything.

Macroscopic quantities of plutonium can only be made in a nuclear reactor; and this requirement dictates that when formed it will always be formed in the presence of fission products. In commercial nuclear reactors, the mass ratio of plutonium formed to fission products is roughly 1:4.

At Hanford, these fission products - for almost the entire history of nuclear energy fission products have been arbitrarily assigned the term, "nuclear waste" - were dumped into a series of now famous "waste" tanks, tanks which are now being "cleaned up" at a cost of billions of dollars because they are leaking radioactive stuff.

Oh my God!!! They're leaking!!!

Many fission products have relatively short half-lives and decay to stable isotopes while still in the reactor, generating about 3% of the heat utilized - in commercial nuclear reactors - the heat that drives the turbines. Examples of such products are all of the fission products having a mass number of 133, or a mass number of 138, or a mass number of 127, or mass number 98...

Others famously do not.

Some radioactive isotopes will not decay to stable isotopes in the lifetime of the planet. For instance, fission isotopes having a mass number of 115 will decay into the radioactive (and apparently toxic) element indium, Indium is one of the only radioactive elements - along with tellurium and rhenium - to possess a stable isotope (in the case of indium it's the 113 isotope) which is present in quantities smaller than the radioactive isotope in all of its mined ores. In fact, natural indium contains only roughly 4% stable indium-113, and roughly 96% radioactive indium-115. If you have a cell phone in your pocket, you have radioactive indium in your pocket.

The reason that there isn't much stable indium on the planet is because all of the world's cadmium is radioactive, and contains the radioactive isotope Cd-113, the precursor of In-113, blocking the formation of Indium-113 from the primordial nuclear events that created all the heavy elements on this planet. Cd-113 has been decaying into indium since the formation of this planet, and it will be doing so around the time the sun reaches red giant stage and eats this planet whole. However it is decaying very slowly: It's half life is 77 quadrillion years, and it has survived since the formation of the earth and makes up about 23% of "natural" cadmium.

As is the case with the long lived isotope uranium-238 - so called "depleted uranium" - the chemical toxicity of both radioactive naturally occurring cadmium and radioactive naturally occurring indium vastly outstrips the radiotoxicity, which in all three cases is trivial, but not zero.

Cadmium, Indium, and Tellurium (again, in the same class as indium with respect to ratios of stable to radioactive isotopes) are all used in solar cells, meaning that the chemotoxic wastes that into which they will all be transformed will all be radioactive waste as well, much like the thorium containing mine tailings for all the lanthanides mined to make electric cars and wind turbines. However, the longer an isotope's half-life, the smaller its radiologic risk will be. The radioactivity of cadmium, indium, cadmium and thorium probably account for less than 10 deaths (out of tens of millions of deaths) each year.

As far as I can tell, nobody in the general public cares very much about cadmium or indium in Hanford's tanks, apart from the scientists involved in the clean up who realize that these elements must be there, because, um, they're scientists.

What really get's the public imagination going is the element cesium, the same stuff that prominently leaked, generating millions of barely literate news stories and internet posts - out of the Chernobyl and Fukushima reactors. Those old enough to remember, will recall that cesium isotopes also generated huge panics during the era of open air nuclear testing many years before Chernobyl and Fukushima. Cesium's most famous radioactive isotope is the 137 isotope, which has a half-life of 30.23 years and is very, very, very radioactive and in secular equilibrium with an even more radioactive isotope, Ba-137m, which exists a few minutes before decaying into stable nonradioactive Ba-137.

If you were born after 1945, you have lived your entire life being exposed to Cs-137 in amounts that grew continuously until roughly 1963, and have tapered off since, with a few spikes from Chernobyl and Fukushima. Up until 1963, with rare exceptions thereafter, the stuff was routinely vaporized in the planetary atmosphere, and somehow did less damage than the currently ongoing practice of vaporizing coal on a far more massive scale. Vast quantities of coal are being vaporized today.

I have been reading about the chemistry and physics of radioactive elements associated with nuclear energy, as well about topics in nuclear engineering, for more than 30 years, relying heavily on the primary scientific literature to do so. And while I am always interested in the geochemistry of radioactive materials that have been added to the environment from nuclear fuel reprocessing, nuclear accidents, nuclear weapons testing, and nuclear war - the number of nuclear wars being one, in contrast to the number of oil wars, which is considerably greater than one - I can't say that it amounts to more than 10% of my readings on nuclear issues. Readings about Hanford, in general, represent in turn only a small percentage of that 10%. The truth is that I am far more interesting in the processing and use of fission products than their environmental fate, since as environmental issues go the effects of radiation are trivial when compared to the effects of air pollution and climate change.

Whenever I've been presented with idiotic stuff about Hanford - a recent example consisted of a very stupid interaction with a commentator about the collapse of a tunnel at Hanford, this on a planet where 19,000 people will die today from air pollution - I am usually dismissive: I like to note that even if the 44,000 people living in Richland, WA, the "home town" of the Pacific Northwest National Laboratory at Hanford, were all wiped out by Hanford "nuclear waste," the disaster would amount to a little over two days worth of deaths from air pollution. Of course, Hanford hasn't been wiped out by radioactive stuff, and frankly, it won't be.

Whenever I hear or read about cesium plumes under leaky Hanford tanks, I generally sigh to myself, without paying much attention, "Why the hell don't they just run that crap through an ion exchange resin and be done with it?"

Recently in my regular reading in one of the journals I regularly read, I came across a paper that has increased my attention to the fascinating issue of the Hanford tanks, specifically, this one: Review of the Scientific Understanding of Radioactive Waste at the U.S. DOE Hanford Site (Peterson et al, Environ. Sci. Technol., 2018, 52 (2), pp 381–396).

The paper is so interesting that I did something that is somewhat unusual, I downloaded pretty much every scientific reference in the paper, with a few inaccessible omissions, and then references in the references.

I won't talk more about this paper itself in this post although I may do so in the future here, but will instead site one of the references, a document entitled, "Sixteen Years of Cesium Recovery Processing at Hanford's B Plant" (RHO-RE-SA-169). You can find this document in full on the internet, but it took me a while to find it before downloading it, and I'm too lazy to find it again, so I won't link it here.

"Why the hell don't they just run that crap through an ion exchange resin and be done with it?..."

Well, it appears that they pretty much did that.

The text referring to RHO-RE-SA-169 from the Peterson paper cited above is this:

Strontium and Cesium Separations.

Strontium-90 (t1/2 = 28.6 y) and 137Cs (t1/2 = 30.2 y) are major contributors to the heat generated from nuclear fission wastes. These isotopes also have potential commercial value 90Sr as a source of 90Y used in medical applications,18−20 and 137Cs as a source of γ rays (through decay of its daughter 137mBa, which emits a 662 keV γ ray) for sterilization applications.21 Megacuries of these two isotopes have been separated from acidic process solutions and from tank waste at Hanford.22

The cited reason that Cs-137 is valuable, by the way, is somewhat superficial. Cs-137 can be and is used for sterilization, but this is only a tiny reflection of its utility. Gamma radiation can solve some otherwise very intractable environmental problems, in particular those involving pollution with legacy (for example DDT, CFC and PCBs) and ongoing chemical pollution of the atmosphere and bodies of water, among other things. Regrettably this utility is vastly under explored and utilized.

Following references in reference 22 leads one to the "Sixteen years" report, which was published based on a talk given at a meeting of the American Nuclear Society at Niagara Falls, NY, in September 1986, a little more than 5 months after Chernobyl blew up. Chernobyl was the event that lead me to serious reading about nuclear energy, and the more I read, the more I found reason to change my mind about lots and lots and lots of things, only one of which involved the question of whether nuclear energy was a bad thing or a great thing.

The "Sixteen Years" document refers to operations at Hanford to recover Cs-137 that began shortly after Christmas in 1967 and was ended after 1979, with processing of the recovered cesium continuing for several years after that, continuing until 1984.

The separation process, was, in fact, an ion exchange process.

"Why the hell don't they just run that crap through an ion exchange resin and be done with it?..."

By the way, the events described in "Sixteen Years" were not the first attempt to separate cesium from the fission products that went into the Hanford tanks.

In 1957, near Kyshtym in the former USSR, there was a chemical explosion at the Soviet nuclear weapons plant in the closed city Mayak, which served the exact same function for the Russian nuclear weapons program that Hanford played for the Americans. The explosion is said to have involved nitrates used in the separation plants. Although this was a chemical explosion similar to the explosion that the domestic terrorist Timothy McVeigh used to strike Oklahoma City and not a nuclear explosion, it took place in a storage tank that was more or less the equivalent of the Hanford tanks, a highly radioactive mishmash of fission products. It is estimated to have released 20 million curies of radioactivity, two of which were aerosols and were distributed over a wide area.

Nitrates were also used in American operations, but along with something else, nickel ferricyanide. The heavy group one elements potassium, rubidium and cesium all form insoluble salts with iron and nickel cyano complexes, in the iron case referred to as ferrocyanides. (Ferroferricyanide salt is a chemical compound formerly used as a dye known as "Prussian Blue," which was sometimes used as a wet analytical test for iron.)

In the early 1950's ion exchange technology, while known, was in its infancy. In 1954 a flow sheet was published for the removal of cesium-137 from fission products in order to reduce the heat load in the Hanford Tanks being filled at that time. (cf HW-30399, AEC Research and Development Report, 1954.)

Decades later, when the contents of the tanks were being investigated, scientists recognized that the material dumped into the tanks from this process, along with hot radioactive materials might well explode. Between 1954 and 1958 about 140 metric tons of ferricyanide found its way into 18 Hanford tanks.

At the same time, nitrate wastes - nitric acid was widely used in the PUREX plutonium separation process to recover plutonium - also found their way into the tanks.

A very exothermic reaction between sodium nitrate and nickel ferricyanide in which the two compounds react explosively to form nitrogen gas, sodium carbonate, nickel (II) oxide, iron (II) oxide and carbon dioxide. This reaction releases 9 MJ of energy per kg. (cf. HNF-SA-3126-FP, Resolution of the Hanford Ferricyanide Safety Issue.) This implies that were the ferricyanide evenly distributed among each of the 18 tanks, that each tank would contain about 7.8 tons of ferricyanide, and the chemical explosion in a tank would release about 73 GJ of energy, equivalent to a 17 "Megaton" chemical explosion.

That would have been bad.

It turns out that the cyanide in the tanks was radiolytically decomposed resulting in a much milder reaction that essentially ate up all that dangerous stuff.

And now about the "Sixteen Years."

Three forms of ion exchange were utilized. The first one of which was Linde AW-500, an aluminosilico zeolite. The uptake of cesium was recorded in a straight forward manner. The "waste" solutions were passed over columns at a rate of about 40 gallons per minute, and the radioactivity of the eluent was monitored. When radioactivity began to show up, it the resin was fully loaded, and the elution was stopped and the cesium removed from the resin by elution with ammonium carbonate, evaporated, and sent for processing. When the Linde AW-500 was found to show poor long term stability under radiation loads, it was replaced with Norton Zeolon 900, also an aluminosilicate zeolite. When this too showed poor long term stability under radioactive loading, they were ultimately replaced with an organic ion exchange resin, Duolite ARC-359, a sulfonated phenolic formaldehyde resin.

Apparently over 116 million curies of cesium-137 was recovered in this way, almost six times the amount of radioactivity released in the Mayak disaster.

All of this cesium was immobilized in the form of a cesium phosphotungstate having a ratio of sodium to cesium of 10:1 and encapsulated into 1500 stainless steel containers, in which they remain today, with some having been distributed to licensees for use.

The 116 million curie figure is kind of ambiguous, since the cesium was undergoing radioactive decay throughout the 16 year process. It may refer to the amount loaded or the final amount at the end of the campaign in 1986. For simplicity, I will assume the latter.

In 1986, 116 million curies of cesium-137 - given the specific activity of cesium at 4.4 hundred trillion Becquerel per mole, would amount to 1.34 tons of the stuff.

In equilibrium with Barium-137m, it can be shown that in 1986, 116 million curies of cesium would be putting out about 1.26 MW of power.

By 2018, this material has decayed to 47.8% of the original amount, and now represents about 683 kg, putting out about 604 kW of power.

My kid is in his first year of college and is taking a course in differential equations and another in the thermodynamics of materials. I asked him to set up an equation and solve it to demonstrate what volume of the water contaminated with PCB's in the Hudson River superfund site, which is now being dredged even though there is actually no safe place to put the dredgings, could be heated and boiled off in a reactor heated with this much energy, in the process destroying and mineralizing the PCB's.

He blew me off. I don't blame him. He's busy. Anyway a soxhlet type arrangement extracting the PCB out of the dredgings with isopropanol would be superior for this purpose, and the thought experiment actually proposed a dumber idea than a practical use.

The point I wanted to make for him, since his generation will need to clean up our mess since we didn't give a shit about future generations when we made this mess, is that these kinds of radioactive materials can be very useful for this purpose. He didn't solve the problem - which has a simpler solution actually than one involving differential equations - but he got the point.

In fact, not all of the cesium remains at Hanford. Recently I got to see a photograph of one of the canisters while attending a lecture on radiologically stable artificial muscles (which were ultimately tested in space, where the radiation field is constant) but before being flown in the space station were subjected to ground based gamma radiation.

A video of that lecture is here: Science on Saturday: Synthetic Muscle for Deep Space Travel

Here's something interesting to ponder if you actually made it through this too long post: The Hanford clean-up is a mess that a previous generation left for our generation to clean up. It's likely very possible to clean it up by the way, challenging, expensive if interesting, but clearly possible.

The ultimate death toll of the Hanford tanks will be thankfully small, probably not zero, but certainly not more than the equivalent of a few hours - if that - of air pollution deaths.

Our generation is leaving all future generations fracking fields bleeding all sort of chemicals and elements, some of which, chiefly radium and its daughters, are highly radioactive. No one is cleaning it up. We're pretending it's not there, just like the people who were working at Hanford didn't worry about the long term consequences of what they were doing.

Much worse than the fracking fields is the condition of our atmosphere. This week, after years of jaw boning, we're at 410 ppm of carbon dioxide in the planetary atmosphere, and rising, rising fast.

I spend a lot of time wondering if it is even possible to clean up the mess we're leaving, a mess that dwarfs Hanford, dwarfs Chernobyl, dwarfs Fukushima, and is not limited to specific geographical areas but involves the entire planet.

If we complain about the indifference of the people who filled the Hanford tanks, we will be Trumpian in our hypocrisy. We will be Trump scale liars, because what we are doing is far worse, and far less possible to solve, even with hundreds of trillions of 2018 dollars.

I wish I lived in a time where people, in general, could get beyond emoting and simply think.

Simply think...

Enjoy the rest of the weekend.

I wake up each morning looking for a beautiful thing. This morning its the square Archimedian...

...antiprism structure of ZrF8.

I know I'm something of a strange bird, but I'm a strange bird who has the great fortune of feeling how wonderful it is to have lived.

Life is very beautiful, if you let it be so.

Tracking the Source of Fecal Contamination in Recreational Freshwater.

You see stuff like this, and you really don't want to believe it:


Solar Works Wherever People Live


It is a bourgeois conceit - and regrettably it is prevalent on our end of the political spectrum - that so called "renewable energy" is a viable solution to poverty on this planet, poverty being something about which very few of us actually know anything at all and about which we care even less.

Here's a clue: The overwhelming majority of people who live in bamboo and grass huts are not looking for a solar cell to power their video games. In fact, the main effect that solar cells is likely to have in the third world will be to raise the serum levels of toxic metals in children of all ages when this stuff turns into electronic waste - which it will before most middle aged bourgeois people die - and is sent to third world countries to be "recycled" so everyone in rich countries can feel all "green."

Solar energy is useless in the first world, and if anything it is worse than useless in the third world, given, as is the case with everything else, the lives of third world human beings are considered expendable in order to provide for the smug complacency associated with citizens of the first world. The third world is where the most toxic materials for "green" renewable energy is mostly mined, and it will be the place where most of it will end up being dumped.

It's disgusting.

One of the largest health risks in the third world, besides air pollution for which the solar industry has just racked up half a century of doing nothing to address - is the lack of adequate sanitation.

Some notes from the World Health Organization's "fact sheet" associated with this issue:

13% of the global population (0.9 billion people) used toilets or latrines where excreta were disposed of in situ.

68% of the world’s population (5.0 billion people) used at least a basic sanitation service.

2.3 billion people still do not have basic sanitation facilities such as toilets or latrines.

Of these, 892 million still defecate in the open, for example in street gutters, behind bushes or into open bodies of water.
At least 10% of the world’s population is thought to consume food irrigated by wastewater.

Poor sanitation is linked to transmission of diseases such as cholera, diarrhoea, dysentery, hepatitis A, typhoid and polio.

Inadequate sanitation is estimated to cause 280 000 diarrhoeal deaths annually and is a major factor in several neglected tropical diseases, including intestinal worms, schistosomiasis, and trachoma. Poor sanitation also contributes to malnutrition.

WHO Fact Sheet: Sanitation

We may all feel smug about this not being our problem, although I can tell you my septic system failed a few years back and I got a new appreciation of this issue, even though I'd been considering it sometime.

A paper published in the current issue of Environmental Science and Technology suggests that even if it's not the same level of problem as it is for people living in grass huts powered by swell solar cells, maybe cadmium telluride babies, it's not entirely trivial for first world bourgeois types.

The paper is here:

Application of SourceTracker for Accurate Identification of Fecal Pollution in Recreational Freshwater: A Double-Blinded Study (Sadowsky et al, Environ. Sci. Technol., 2018, 52 (7), pp 4207–4217)

From the introductory text:

Fecal pollution of water is a significant global health issue due to the likely presence of waterborne pathogens. Therefore, identification of the source(s) of fecal pollution is critical for implementing appropriate remediation strategies and protecting human health risks associated with water use and reuse. Fecal pollution of environmental waters has been historically assessed by enumerating fecal indicator bacteria (FIB), such as Escherichia coli, Enterococcus spp., and Clostridium perfringens using culture-based methods.(1) However, monitoring FIB in environmental waters does not provide information on the source of pollution, e.g., human or animal feces,(2) or naturalized FIB in the environment,(3,4) necessitating the use of microbial source tracking (MST) methodologies. Early MST tools were library-dependent and required isolation and typing of hundreds-to-thousands of FIB from human and animal feces to generate source-associated libraries.(5−7) Conversely, library-independent methods target a gene fragment from a taxonomic group that typically coevolved, or is otherwise associated (e.g., by infection), with a specific host, providing a host-associated marker typically enumerated by quantitative PCR (qPCR).(2)...

The authors note that the most modern methods, based on qPCR technology, for determining the source of fecal matter has demonstrated ambiguities which they seek to resolve using machine learning type algorithms.

The goal is to distinguish fecal sources from horse, cows, cats, dogs and wastewater treatment plants (WWTP). The study was double blinded to determine the accuracy of their methods.

I don't have much time this evening, and won't go through the paper in any detail, but will show some pictures from the paper along with captions, and then offer some text from the conclusion:

The caption:

Figure 1. Principal coordinate analyses of Bray–Curtis dissimilarities among source bacterial communities. Samples were broadly grouped to host categories including A) domestic (r2 = 0.43); B) livestock (r2 = 0.82); C) avian (r2 = 0.30); D) wildlife (r2 = 0.47); E) WWTP (r2 = 0.71); and F) WWTP + avian (r2 = 0.52). MN: Minnesota. The five most abundant genera in each host category are shown and were overlaid on the ordination using the corr.axes command in mothur

The caption:

Figure 2. Linear discriminant analyses of effect sizes (LEfSe) showing differentially abundant OTUs classified to genera. Sources were broadly grouped to host categories which included A) domestic, B) livestock, C) avian, D) wildlife, E) WWTP, and F) WWTP + avian. All analyses were performed at LDA ≥ 4.0. Abbreviations: CA: California; Chick: chicken; H: Hobart; Kang: kangaroo; M: Melbourne; QLD: Queensland.

An "OTU" is an "Operational Taxonomic Unit."

Figure 3. Sink predictions among source categories, with respect to geography, in the initial library. Sources were broadly grouped to host categories which included A) domestic, B) livestock, C) avian, D) wildlife, E) WWTP, and F) WWTP + avian. Approximately half of the samples in each category were assigned as a source and the other half used as sink (shown in parentheses). Error bars reflect standard deviations. The “Unknown” prediction refers to the proportion of the community that was not assigned to a source. Abbreviations: B: Brisbane; CA: California; Chick: chicken; H: Hobart; M: Melbourne; MN: Minnesota; P: Perth; QLD: Queensland.

Figure 4. Genera classifications of OTUs assigned to sinks from the respective source using SourceTracker. Sources were broadly grouped to host categories which included A) domestic, B) livestock, C) avian, D) wildlife, E) WWTP, and F) WWTP + avian. Approximately half of the samples in each category was assigned as a source, and the other half was used as sink. Abundances were normalized to the total sink prediction for each source (Figure 3). Abbreviations: CA: California; Kang: kangaroo; QLD: Queensland.

Some concluding remarks:

Results of this study indicate that identification of fecal source contamination in recreational freshwater using SourceTracker is dependent on the inclusion of geographically associated source samples present in the source library. Using an initial library with geographically divergent sources, but no representation from local sources, blinded source samples could not be unambiguously defined, with mean similarities of blinded source communities <7% to sources in the initial fecal library. Furthermore, despite a great overlap in community composition among certain host species, e.g., avian species, the algorithm was generally able to assign >80% of the sink community to the correct source and geography. These results suggest that, despite taxonomic similarity in the fecal microbial community among closely related sources,(40) individuals vary by geographic region and specific species compositions (here assessed as OTUs), as has been well documented among humans.(41,42)

If you're curious about actual sources of actual shit, you may click on the link to the paper, which is probably not open sourced, and then find the "SI" supplemental information PDF link and open it. This should be open sourced, and you can learn whence shit in recreational waters comes.

You know, we're surely not perfect on the left, and it is not enough to say we're not as bat shit mad as the people on the right, including the orange baboon in the White House. It is not enough to be "not as bad as..."

The challenge is to be good; to be decent, and decency involves, well, to go with the theme here, "giving a shit."

We should care as much about the people in the third world who are described in the WHO fact sheet, as we do about how bad walking our dogs on the beach is for water skiiers.

Just saying...

We can be so clueless:

Solar cells on grass huts...you see this kind of thing, but you really don't want to believe it.

Have a nice "hump day" tomorrow.

Upgrading Low Quality Iron Ores With Biomass Gasification/Coal Tars.

I have no use whatsoever for the ethically vacuous "free marketeer" philosophy, since it posits that some human beings have the right to destroy arbitrarily the lives of other human beings solely for their self interest.

This said, there are two kinds of appeals to "free market" nonsense, the puerile and the sophisticated.

The puerile type consists of the destructive nonsense put out by that vicious and despicable muddled self declared "thinker" Ayn Rand, who unfortunately lived at all - never mind too long - and is embraced by middle aged eternally intellectually teen aged muddle heads like, say, Paul Ryan, whose life experience should have been limited to playing video games in their parents bedrooms, but nevertheless have ended up defending overt racists in, of all places, the House of Representatives.

The sophisticated type is the one that points out that most of us - at least in the so called "First World" - are culpable in the amoral destruction of other human lives - the lives I personally rail about, spitting in the wind, are the lives of all future generations - and that we are by definition hypocrites if we object to the outcome and implication of our lifestyles with respect to other human beings, current and future.

I admire and often study the thinking of the great technological philosopher and scientist Vaclav Smil, whose rhetoric is often of the second type. Note that this is decidedly not of the discipleship type characterized by the Ayn Rand/Paul Ryan Bozo cartoon type, and their "Objectivist" pseudoathesim in which they nonetheless grovel at the foot of a clay goddess who authored holy books for the mindless. No, by contrast, when I read Smil it is often (but not always) to be challenged to find ways to argue that he might be made wrong, even if he is right now.

One of Smil's writings that has challenged me concerns iron - hence the title of this post - this one: The Iron Age & Coal-based Coke: A Neglected Case of Fossil-fuel Dependence.

I never tire of saying that I feel that it is a moral imperative to entirely end dependence on fossil fuels, since they are clearly not sustainable, and yet, as Smil points out, we live and have lived for well more than a millennium, in an age of iron, in modern times, complex steel alloys, all of which rely on the use of carbon, carbon almost always obtained from coal.

Our generation has consumed the best ores for pretty much all of the essential elements in the periodic table, and what remains for the future generations is our table scraps, our garbage and the poor pickings of future generations. This is true to some extent even for very common elements like aluminum and iron. (In the former case, cryolite mines in Greenland were completely depleted by the 1980's and all modern cryolite - the flux intermediate for the Hall electrolysis process by which all aluminum is made is now synthetic.)

It is thus with some interest that I came across this paper in the scientific journal Energy and Fuels that discusses a process for upgrading the low quality iron ore Goethite by combining tars that derive not only from coal, but from biomass gasification. The paper is this one: Integrated Pyrolysis–Tar Decomposition over Low-Grade Iron Ore for Ironmaking Applications: Effects of Coal–Biomass Fuel Blending (Akiyama et al, Energy Fuels, 2018, 32 (1), pp 396–405)

Biomass gasification is one of a few technologically feasible paths for removing the dangerous fossil fuel waste carbon dioxide from the atmosphere - but only if the heat is provided by nuclear energy, and not by combustion. However, in the case of many of these processes, most of them in fact, a side product remains, "tars" and/or "asphaltenes."

From the introductory text:

Presently, ironmaking industries face problems related to the depletion and shortage of both high-grade iron ores as raw materials as well as carbonaceous material as a primary reduction agent. The effective utilization of low-grade ores, such as goethite (FeOOH), in the modern ironmaking industry is highly attractive to solve problems related to the depletion of high-grade iron ores. Goethite, however, cannot be directly charged into a blast furnace as a result of its high combined water content.(1-6) Previous researchers proposed a new process called the integrated biomass or coal pyrolysis–tar decomposition process that solves these problems simultaneously. This process aims to reduce tar by decomposing it as deposited carbon over low-grade iron ore as well as using chemical vapor infiltration (CVI) to produce carbonized ore.(7) The report described fundamental experiments of an ironmaking process that used low-grade iron ore and woody biomass. The decomposition of biomass tar produced carbon that deposited within the iron ore pores, resulting in partial reduction of the iron. Furthermore, nanocracks suitable for carbon deposition were initiated and propagated during this dehydration. Carbon tar completely filled the nanocracks and increased the carbon content, which could be used as a potential reduction agent.(8) A similar method was applied using steelmaking slag as supplementary fuel in a sinter machine.(9) The CVI ore can then be used for ironmaking applications because it has a higher reduction reactivity as a result of the nanoscale contact between iron oxide and carbon.(10) Investigations have been performed on the carbon deposition of various solid fuels, including high-grade bituminous coal, low-grade lignite coal, and biomass palm kernel shells.(11) However, a new challenge was introduced: to produce a CVI ore with a higher carbon content as a reduction agent.

In modern blast furnace operation (typical case in Japan), 385 kg of coke per ton of hot metal is needed, while 112 kg of pulverized coal per ton of hot metal is injected.(12) For every ton of coke produced, around 1.6 tons of coking coal is used.(13) However, because high-grade coal (coking coal) tends to be expensive with limited availability, the utilization of biomass (mainly wood) as a substitution for coal (which is a non-renewable carbonaceous material) also gained much attention in an attempt to reduce greenhouse gas emissions. Furthermore, utilization of any individual biomass material normally faces several problems, such as seasonal harvesting, which limits year-round availability, higher transportation costs, and lower fuel qualification properties.(14)...

The chemistry of biomass is extremely complex, especially since practical sources of it involves hundreds if not thousands of species grown under variable conditions. Further adding to this complexity, a plethora of strategies for processing it into gaseous compounds exist. The authors offer a brief description of a current highly sophisticated effort to rationalize some of these parameters by referring to what is called the "Distribution Activation Energy Model" or DAEM, which evokes a beautiful looking equation.

The authors write:

The basic assumption of the DAEM is that many solid fuel decomposition reactions take place during pyrolysis. It can be simply approached as a sum of an unlimited number of parallel first-order decomposition reactions. When multiple Gaussian distributions of activation energy are applied, the DAEM equation can be written as

where Xcalc is the calculated residual volatile fraction of solid fuel at a given time, n is the number of activation energy distributions, β is the heating rate (K s–1), k0i is the pre-exponential factor of constituent i (s–1), σi is the activation energy variance of constituent i (kJ mol–1), E0i is the mean activation energy of constituent i (kJ mol–1), R is the gas constant (J mol–1 K–1), and T is the absolute temperature (K).

The authors walk us through a few iterations of this equation to get an even more beautiful looking equation, this one:

At this point, I plainly confess that the actual use of this equation if over my head, despite the obvious appeal to the Arrhenius law in the integral in the exponent of another integrated exponential, but that's OK, because this is the first time in my life I ever heard about DAEM related work with respect to biomass gasification. Playing with that equation has to be fun. I do hope to find the time to get to the references some day and learn about this beautiful thermodynamics.

You learn something every day...if you're lucky, and I am lucky, bourgeois piece of crap that I am.

Anyway, the authors get down to performing some experiments with biotars and coal tars.

Here's a schematic of their apparatus:

The caption:

Figure 1. Apparatus configuration for integrated pyrolysis–tar decomposition–carbon deposition over iron ore.

It looks like a mini-retort.

They study their process by the use of thermogravimetric analysis, (TGA), a TGA being a device that measures the loss of mass as a substance is heated. This is plotted along with the DTG, the "Differential Thermogravimentric" curve, which represents the rate of decomposition, in essence the derivative of the TGA output as a function of temperature.

The caption:

Figure 2. TG/DTG profiles and the highest decomposition rate temperatures for coal–biomass blending with different BBRs during pyrolysis. Coal and biomass particle size = 125–355 μm.

Here "BBR" refers to the biomass blending ratios, the ratio of biomass to coal.

It is useful to stop here to speak about the coal component of this system, since many of my writings on the internet are adamant that coal mining and use should be phased out rapidly. With due deference to the exceptional mind of Vaclav Smil, I do believe that synthetic coal that will be superior to mined coal is in the realm of possibility and further, with input of energy, and I also believe it is technically feasible to make synthetic coal from, um, carbon dioxide. The path for doing this would involve (besides procuring the carbon dioxide) a metal based carbon dioxide splitting thermochemical system driven by nuclear heat or by reformation of either waste plastic or biomass with carbon dioxide as an oxidant. The resultant carbon monoxide could then be disproportionated into pure carbon and carbon dioxide using a chemical equilibrium - also a function of temperature - known as the Boudouard equilibrium, CO2 <-> CO + C.

All that is required is energy, which at least in theory is available in unlimited supply since uranium is available in unlimited supply, since there is so much uranium on this planet that humanity could never consume all of it without vaporizing the planet, something that is obviously to be avoided, even if it is possible.

With appropriately Rube Goldbergish heat flows, this need not be all that expensive for future generations, who couldn't possibly be more stupid than our generation, a generation that has allowed an orange baboon with a poor intellect and a non-existent ethical matrix that is Ayn Randian in dimension into the White House.

In any case, coal that finds its way into steel making is at least partially sequestered more or less permanently, at least in high carbon steels.

On this score, it is popular on the American left - and I say this criticizing my own demographic - to pretend that "coal is dead," because the orange baboon has represented that he was going to restore allegedly "dead" coal in the United States. The American left also likes to pretend that the "fastest growing source of energy" on this planet is so called "renewable energy," one component of which, wind energy, is highly reliant on access to steel.

Neither of these pretensions are even remotely true, as I repeatedly point out by reference to the International Energy Agency's World Energy Outlook 2017 report:

IEA 2017 World Energy Outlook, Table 2.2 page 79

Converted MTOE in the original cited table table in the report to the SI unit exajoules in this text one can learn that allegedly "dead" coal has been for the entire 21st century the fastest growing source of energy on this planet, having increased by 60.1 exajoules in the period between 2000 and 2016, 2016 being the last year for which data has been fully compiled. Overall the consumption of coal has risen to 157.2 exajoules out of 576 exajoules the report says was being consumed as of 2016. This makes coal only second to dangerous petroleum as a source of energy on the planet, which grew by "only" 30.1 exajoules to a total of 183.7 exajoules.

The entire so called "renewable energy" scheme, after sucking trillions of dollars out of the world economy does not produce even 10 exajoules of energy, 9.4 to be more precise, having grown by only 6.9 exajoules in the 21st century, or a little more than 11% as fast as coal, never mind dangerous petroleum and dangerous natural gas.

Anyway, back to steel making with biomass cut with a little dangerous coal:

The authors work to explore the parameters in the DAEM equations evoked above and, then, continuing to look at the pictures as a way of understanding this work they produce the following bar graph:

The caption:

Figure 4. Carbon yield product distribution of integrated pyrolysis–tar decomposition in a N2 atmosphere at a pyrolysis temperature of 1073 K and a tar decomposition temperature of 873 K for 40 min. Case A, co-pyrolysis only; case B, co-pyrolysis with tar decomposition over porous iron ore (3 g).

Here's a blurb from the text discussing the bar graph:

The integrated coal–biomass co-pyrolysis–tar decomposition over low-grade iron ore was designed to reduce the tar product while simultaneously converting it to carbon deposited into the iron ore. Moreover, production of high carbon content carbonized ore is desired. Figure 4 shows the product distribution carbon yields from integrated coal–biomass pyrolysis, for both pyrolysis only (case A) and pyrolysis–tar decomposition over porous iron ore (3 g) (case B). The observed pyrolysis products were the carbon yield of char, heavy tar, light tar, deposited carbon in iron ore (case B only), and gas at any BBR. Heavy tar and light tar in this experiment were separated by the boiling point according to the International Energy Agency (IEA) tar protocol, in which the components with the boiling point higher than 378 K could be categorized as the heavy tar fraction.(35) The deposited carbon in iron ore is the carbon amount of solid fuel that deposited in the iron ore bed during the CVI process, which was evaluated from mass balance. In contrast, the carbon content in iron ore was measured by the CHN/O/S elemental analyzer. The term of the deposited carbon and the carbon content in CVI ore were introduced to distinguish the different points of view. It was obvious that the total carbon yield of the biomass pyrolysis product is lower than the coal product because biomass has a lower carbon content than coal. Total carbon yields of the coal–biomass blends gradually decreased at elevated BBRs.

Note that the main product here in terms of mass is gas. It is important to consider what these gases are, since coal is involved and the potential for dumping gases into the planetary atmosphere as fossil fuel waste is not acceptable, even if almost universally practiced.

Another figure from the text, showing gas compositions:

The caption:

Figure 7. Effect of co-pyrolysis at different BBRs on gas H2, CH4, CO, and CO2 product distribution of integrated pyrolysis–tar decomposition in a N2 atmosphere for 40 min at a pyrolysis temperature of 1073 K and tar decomposition temperature of 873 K. Case A, co-pyrolysis; case B, co-pyrolysis with tar decomposition over porous iron ore (3 g).

The point here was to convert a low grade iron ore, goethite, the table scraps we leave for future generations as an expression of our generalized contempt for our children and their decedents - our contempt for humanity as a whole - into an ore of a quality that we enjoyed but squandered on quixotic enterprises like cars and idiotic wind turbines, magnetite. This has been achieved by this process.

By reference to the immediate figure above, a note is in order about the composition of the gas component.

Here is the chemical equation for the pyrolysis reactions:

The authors write:

The significant increase of H2 and CO2 at higher BBRs could be correlated to the presence of water from biomass pyrolytic tar-promoting steam reforming, as in eq 8, and water-gas shift reaction (WGSR), as in eq 9.

The "water gas shift reactions" are these:

The gases above, as mixtures of carbon oxides and hydrogen are forms of what are known as "synthesis gas" or "syn gas" for short, from which pretty much any modern commodity carbon compound may be formed. (Such practices may require hydrogen from thermochemical or biomass reforming based water or carbon dioxide splitting.) To the extent that such practices result in polymers, or engineered carbon products such as carbon fibers, graphene or carbon based ceramics such as metal carbides and MAX phases, they represent economically valuable carbon sequestration.

They need not be dumped in the atmosphere as waste, despite our current practice.

A better world is possible, even if it is less and less likely.

Enjoy the weekend, and if you come from a Christian cultural background, have a happy Easter.

I had a Freundlich exponent when I was a kid, but I went away for a weekend and my Mom...

...forgot to feed and it and died.

I've been absorbed in grief ever since.

I don't know why I had to say that, but I just did.

Go back to your normal lives...
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