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NNadir

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Gender: Male
Current location: New Jersey
Member since: 2002
Number of posts: 26,612

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The Mirror of Life

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Henry Koerner (1915-1991), (Austrian, American) Mirror of Life, 1946. Oil on composition board, 36 × 42in. (91.4 × 106.7 cm). Whitney Museum of American Art, New York

Addressing the Flammability of Lithium Batteries Using Polystyrene Ionogels.

My son just finished his first semester, very successfully, in Engineering School; I'm a happy and proud dad.

One of the pleasures of having him home is to watch Air Disasters on the Smithsonian Channel, which is a wonderful show to watch with a budding engineer, particularly a budding materials science engineer, since many aircraft failures turn out to be problems in materials science.

The job of engineers is to make the lives of human beings safer and more sustainable, and one of the most important tasks in this enterprise is failure analysis, which is what "Air Disasters" is all about, failure analysis.

(There is good television, if you look.)

A recent episode, which I had to watch alone, concerned the crash of UPS 6, a cargo plane that crashed in Dubai in 2010 despite a heroic effort by its two crew members to land the plane after it has caught fire spontaneously.

The cause of the fire was determined to be spontaneous combustion of lithium batteries. Lithium batteries, of course, are widely used in computers, cell phones (including the Samsung Galaxy 7), and stupid electric cars, and, as Dubai is an air cargo transportation hub for shipping electrical components, it was hauling a few tons of highly flammable lithium batteries.

It was thus with interest that I came across a paper in the scientific literature which is about research into a means to address this problem - the flammability of lithium batteries is tied to the organic solvents utilized as electrolytes, generally organic carbonates, both symmetric and asymmetric. The paper is here: Syndiotactic Polystyrene-Based Ionogel Membranes for High Temperature Electrochemical Applications (Jana, et al (ACS Appl. Mater. Interfaces, 2017, 9 (36), pp 30933–30942)

Some excerpts from the introduction to the paper:

A new generation of high-temperature materials for energy storage applications is the need of time owing to the rise of usage of high-power electric vehicles, aircraft, and pulsed power systems that require energy storage devices for their functions often at elevated temperatures.(1) Lithium-ion batteries (LIBs) present the most suitable storage technology for electric vehicles (EVs) due to their high energy density and better cycling performance over other battery chemistries.(2)...

...Current LIB technologies show thermal stability up to 50 °C; at higher temperatures, LIBs lead to hazards like thermal runaway, gas evolution, and ultimately fire; the primary responsible factors are the volatile liquids used as the electrolytes.(3) The battery packs of hybrid electric vehicles (HEVs) and electric vehicles (EVs) are cooled to ambient temperature to prevent the hazards.(1, 4) The most common cooling agent is air, while more effective liquid-based cooling systems are incorporated to keep up with the increasing demand of higher power in cars that use big battery packs. It is reported that these liquid coolants can be conductive when hot and can, in turn, cause the short circuit of the cells.(5) In this context, a high temperature Li-ion battery (HT-LIB) that is stable and produces higher power density can potentially reduce or even eliminate the energy requirements to cool the battery packs and to allow an overall simplified vehicle cooling system.(4)

Traditionally, the cathode and the anode of the LIBs are highly researched areas, while the electrolytes and separators receive much less attention.(6, 7) A major source of hazards in LIBs originates from the use of highly volatile organic liquids as the electrolytes.(7-9) The carbonate-based liquids are often limited to usage temperatures below 50 °C due to their high volatility and flammability that often lead to such risks as fire and explosions. Ethylene carbonate (EC), propylene carbonate (PC), and diethyl carbonate (DEC) are the most commonly used carbonate-type liquids used in LIBs.


In general, although there is much pop rhetoric to the contrary by people who consider themselves to be environmentalists without actually appreciating the cold hard facts associated with environmental issues, a battery is not a device that increases energy efficiency. Quite the opposite is true. The second law of thermodynamics, which cannot be repealed, dictates that a battery is a device that always wastes energy. It follows that an electric car is also a device that wastes energy, a matter of high environmental relevance in the case where electricity is generated using dangerous fossil fuels, which overwhelmingly, is how most electricity is generated.

This paper adds another point, which is that cooling batteries - anything that needs to be cooled is dumping energy into the environment where it cannot be recovered - can and often does even waste more energy to run the cooling device.

The authors note that the recall of the Samsung Galaxy 7 smart phone because of the spontaneous outbreak of fires originating in the battery was tied to this issue and give the motivation for the research is to address this very real problem:

...The root causes for battery failure were identified as inadequate volume to accommodate the negative electrode and the defects originating from welding.(11) The associated thermal run-away events causing explosion and fire were the products of high volatility of the organic liquids. This work provides an alternative to alleviate the concerns associated with the use of highly volatile liquids and thermal stability of the polyolefin membranes currently used in fabrication of LIBs...


Their work involves the synthesis and evaluation of a syndiotactic polymer impregnated with the salts of an ionic liquid, and ionic liquid being a low melting salt of one or two stable organic ions.

Here is their description, not a bad one, of the relevant points associated with ionic liquids, which is that they don't really have a vapor pressure - a tendency to evaporate - and they therefore are not generally flammable, except at extremely high temperatures, temperatures not found in batteries that are not on fire:

The ionic liquids have the potential to replace the hazardous carbonate-type liquids in LIBs due to their nonvolatile nature, nonflammability, and high ionic conductivity.(12, 13) Their properties can be tuned using several combinations of cations and anions. In this regard, pyrrolidinium-based ionic liquid, for example, 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide (PYR14TF2N) is suitable for high temperature applications as it is thermally stable up to 300 °C and provides ionic conductivity greater than 1 × 10–3 S/cm.(14-16) Pyrrolidinium cations offer broad electrochemical window in comparison to imidazolium cations when combined with the same TF2N anions in the IL molecular structure.(17) The presence of such ILs allows the use of anode materials with low electrode potential such as graphite. In this work, the ILs are introduced in LIBs in the form of ionogels where the meso- and macropores of a polymeric gel substrate with porosity greater than 90% are filled with the ILs



The authors go on to describe in considerable detail, the process by which they prepare their new electrolyte and then study it using instruments like DSC (differential scanning calorimetry) and TGA (thermogravimetric analysis) as well as evaluating its chemoelectronic properties as an electrolyte.

They compare the performance of their new material with the commercial product in use in lithium batteries today, a product called Celgard 3501.

Their conclusion:

This paper reported a simple two-step procedure for fabrication of sPS ionogel membrane, which was found to be stable for high temperature electrochemical operation, such in LIBs. The porosity of sPS ionogel membranes was significantly higher than that of Celgard-3501 ionogel membranes, which accounted for high IL to polymer weight ratio in the membranes and produced high room temperature conductivity of 6.33 × 10–4 S/cm. The contact angle data showed better wettability of sPS membrane with IL and EC/DEC electrolytes. The high porosity and better wettability of sPS by the electrolyte resulted in lower impedance for sPS ionogels compared to Celgard-3501 ionogel membranes at 25 and 100 °C. The impedance spectroscopy data indicated low bulk charge transfer resistance of sPS-ionogel attributed to better wettability and electrolyte retention of sPS-IL system. The LSV data show improved performance for sPS ionogel membrane over Celgard ionogel membrane at 25 °C. The sPS ionogel membrane also indicated stable electrochemical window up to 4.8 V at 100 °C. This electrochemical and thermal stability of sPS-ionogel allowed continuous operation of LIB cell at 100 °C.


Current lithium batteries can burst into flame at temperatures in excess of 50 °C.

I am not a big fan of storing energy in batteries, except as absolutely necessary. I think that the enthusiasm for them, particularly as macroscale storage devices is misplaced, and is based on the mistaken belief that so called "renewable energy" is sustainable and practical. It hasn't been; it isn't; and it won't be.

My own ideas about energy storage all involve thermal storage, usually in very high temperature materials like, say, supercritical fluids.

But it is very unlikely the need to utilize batteries, particularly in small personal electric devices will go away in the lifetime of anyone now living. Thus this is important research.

I note with less than concealed disgust that this research and all research like it is under threat because a cadre of short sighted and mindless officials holding our government hostage despise science.

I hope you will have a happy and prosperous New Year, and that the New Year will involve the restoration of sanity if not to the White House where fear and ignorance is highly prized, at least then to Congress, now controlled by awful, stupid and extremely ignorant men.

Work for the election of Democrats in 2018!

Get any great surprise books for Christmas?

It's winter break for my boys - they're off from their colleges - and I loved the surprise gifts, history books, with which they surprised me.

One is The Half Has Never Been Told, about how American wealth and its capitalist economic system was generated and sustained through human slavery; the slaves built this country.

The other is The Spy Who Changed the World It's about the nuclear spy/physicist Karl Fuchs, who fed Manhattan Project and British nuclear secrets to the Soviets.

His punishment for his crime - as I told my boys, and they liked the joke - was that he had to live the rest of his life in East Germany.

Distribution of plutonium, uranium and thorium in the tissues of deceased nuclear weapons workers.

In the cold war era there were a number of accidental - and regrettably a number of deliberate - exposures of human beings to nuclear materials.

Some of this has been covered in Eileen Welsome's excellent book The Plutonium Files.

Wandering around, and correctly filing some files I've collected over the years and never read, I came across a cool paper published a few years back about the distribution of the actinide elements plutonium, uranium and thorium, in nuclear workers who were inadvertently exposed to these elements on the job. The tissues were obtained from those collected from those workers after their deaths. The paper is here: Elemental Bio-imaging of Thorium, Uranium, and Plutonium in Tissues from Occupationally Exposed Former Nuclear Workers (Doble et al Anal. Chem., 2010, 82 (8), pp 3176–3182)

The paper includes a description of each of the nuclear workers' accidents, as well as their age at the times of their deaths as well as the cause of death.

The text describing the cases of three sampled workers is worth repeating:

USTUR Case 0303
Case 0303(21) was employed for 30 years at the Hanford complex. He was involved in several minor plutonium exposures and a major exposure in 1968, when he punctured his protective glove and cut his finger on Pu-contaminated equipment. The wound was heavily contaminated with soluble plutonium. Tissue surrounding the wound was excised and intravenous administration of Ca-DPTA enhanced his urinary excretion of plutonium. He did not work with uranium. The registrant died in 2008 at age 87. A tracheobronchial lymph node (taken at autopsy) was studied here.

USTUR Case 0246
This registrant was employed at the Hanford nuclear materials complex in Washington, USA for 25 years.(22) In 1976, an ion-exchange column containing approximately 100 g of 241Am that he was working on exploded, causing him severe acid burns and cuts to his face and upper body. Intravenous Ca-DPTA treatment was commenced promptly, followed by several years of intravenous Zn-DPTA chelation therapy. The Registrant died in 1987 at 75 years of age, from emphysema. Prior to his accidental 241Am exposure, he had suffered a myocardial infarction and coronary artery disease. A right lung superior lobe (taken at autopsy) was studied here.

USTUR Case 1060
This Registrant worked at the Hanford complex for 40 years, where he was chronically exposed to uranium from 1948 to 1950 while working in the uranium melt plant.(23) The form of the uranium was most likely U3O8. Urinalysis suggested there was a single acute incident of uranium exposure occurring in 1948 in addition to chronic U dietary intake. This registrant was also involved in several plutonium contamination incidents and was potentially exposed to elevated airborne plutonium concentrations on two occasions, but only one urine measurement exceeded the minimum detectable activity (MDA) for plutonium. The registrant died (in 2008) at age 83, of a cerebral infarct due to thrombosis of the left carotid artery. A left parabronchial lymph node (taken at autopsy) was studied here.


Laser ablation mass spectrometry imaging is a remarkable analytical technique that has been utilized and advanced notably by Dr. Richard M. Caprioli at Vanderbilt University's Mass Spectrometry Research Center. The technique usually involves imaging of biomolecules (by advanced, but traditional organic molecule focused mass spectrometry) in tissues taken from diseased and healthy patients and represents a tremendous tool for the elucidation of the molecular biology of human disease. It is known by the acronym MALDI-TOF and related terms.

This paper represents one of the few papers I've seen that utilizing LA-ICP/MS (for Laser Ablation Inductively Coupled Plasma Mass Spectrometry) which measures inorganic atoms, in this case actinides.

Here is an image from the tissue of subject USTUR case 407:



The caption: Figure 1. Photomicrograph (top) and m/z 232, 238, 239, and 240 images (65 μm scan spot) of paratracheal lymph node from USTUR case 0407.

This subject's history is not given in this paper, but googling information about him (or her) I was able to learn that he or she lived 47 years after the exposure and died from a Subarachnoid Hemorrhage.

Here's another image from subject USTUR 0303:



Caption: Figure 4. Photomicrograph (top) and m/z 232 and 238 images (65
μm scan spot) of right tracheobronchial lymph node from USTUR case
0303.

Note that the concentrations of these elements are on the order of 100 ng/g (nanograms per gram). Modern mass spectrometry is sufficient these days to measure concentrations of bioactive pharmaceuticals and biomarkers that are 3 orders of magnitude lower, at a level of pg/g (picograms per gram), and a few very advanced accelerator based mass specs even lower than that femtograms/gram.

Many compounds are known to be toxic a pg/g levels.

I wish you happiness and success in the coming year.

Oxygen Isotope Ratios at the Trinity Nuclear Test Site and Laser Fluorination Extraction.

Recently I have been interested in the properties of actinide nitrides - which feature very high melting points - and their use in multiphasic nuclear reactors featuring low melting plutonium/neptunium eutectic liquid fuels, reactors about which I've been musing for some time. It seems to me that these types of reactors could be designed to run, without refueling, for more periods well longer than half a century in a "breed and burn" scenario, where the actinide nitride is UN, uranium nitride consisting of unreacted uranium in used nuclear fuels or depleted uranium, thus eliminating, ultimately, the need for mining anything, oil, gas, coal and, um, uranium for a very long time, for generations.

Nitrogen consists of two natural isotopes, N-14 and N-15 which represent respectively, 99.6% and 0.4% of the content of natural nitrogen. Interestingly Nitrogen-14, the most common isotope by far is, parenthetically, the only stable nuclide in the entire table of nuclides to feature both an odd number of neutrons and an odd number of protons.

In a neutron flux, N-14 undergoes a 14N[n,p]14C reaction during which it is converted into radioactive carbon-14. Carbon-14, as I recently confirmed in a search of the literature, itself has a very low neutron capture cross section which means that it would be extremely useful in actinide carbide fuels which also have extremely high melting points, as well as in known carbide refractories such as silicon carbide, titanium carbide and carbon containing MAX phases. Low capture cross section elements in materials increase neutron efficiency and thus breeding ratios.

(Any attempt to reverse the oxidation of carbon to fight climate change - a formidable engineering task to be sure - will require access to extremely refractory materials to provide high temperatures to produce hydrogen from water thermochemically and carbon monoxide from carbon dioxide, also thermochemically.)

Most of the nuclear scientists whose lectures I have the opportunity to attend are fusion people. They are interested in various cross sections of the light elements, whereas generally, I am not, except as described above, in the case of there presence in fusion fuels. (While their work is fun, none of it will become practical in any time remotely capable of addressing climate change; there are far too many practical issues to address for which they only have a loose approach to addressing.)

I should pay more attention though to the light elements though; their nuclear behavior is important in both fusion and fission systems.

A few years back, in some of my desultory wanderings in the scientific literature, I came across an interesting paper relating to the capture cross sections of light elements. Specifically, the material being tested was "trinitite," the glass material that was first observed after the first nuclear weapons test at the Trinity test site in 1945.

That paper is here: Oxygen Isotope Composition of Trinitite Postdetonation Materials (Koeman et al, Anal. Chem., 2013, 85 (24), pp 11913–11919)

To my personal surprise, they find that the oxygen isotopic ratios at the Trinity test site are not significantly altered, indicating that there was very little neutron capture resulting from the high neutron flux associated with the test, which was, after all, a ground test. The oxygen isotopic ratios were consistent with the natural isotopic fractionation that goes on during the formation of various minerals at the site, which consists of arkosic sands.

(A marker for the neutron flux was the radioisotope 152Eu, which formed from neutron capture in natural 151Europium in the sands. This isotope has a half-life of 13.54 years, and a little more than 2% is still present today at the test site.)

What is also very interesting is the analytical technique that was utilized in determining these oxygen isotope ratios, a beautiful extraction technique called "laser fluorination." This technique is described in the following paper authored by French scientists: IR Laser Extraction Technique Applied to Oxygen Isotope Analysis of Small Biogenic Silica Samples (Alexandre et al Anal. Chem., 2008, 80 (7), pp 2372–2378).

In this technique oxygen is liberated from a sample by oxidation by the powerful oxidant BrF5.

A description from the paper:

Oxygen Extraction Using the IR Laser-Heating Fluorination Technique and δ18O Measurement.

Molecular O2 was extracted from silica in a laser extraction line close to the one described by Sharp.35 A Merchanteck 30 W CO2 IR laser was used. The nickel sample holder was loaded in the sample chamber, prefluorinated with 50 mbar of BrF5 for 1 h and pumped for several hours. In an atmosphere of 100 mbar of BrF5, samples were preheated for 20 s with a 2000 μm diameter laser beam, increasing the power of the laser beam until the particles start moving:  from 0% to 3.6% of the laser full power for fine quartz, 2.2% for diatoms, and 2.6% for phytoliths. The laser emission was stopped after 30 s. Quartz grains and phytoliths were then heated with a 2000 μm diameter laser beam at 30−35% of its full power (11−12 W), starting at the center and slowly moving the laser beam following concentric circles until a bowl of liquid silica formed. Diatom samples were heated with a 2000 μm diameter laser beam, starting at the edge and progressively increasing the laser power from 0% up to 30−35% of its full power (11−12 W), slowly moving the laser beam following concentric circles. For all samples, when a bowl of liquid silica formed, the laser beam was then focused at 1000 μm of diameter until the liquid disappeared. The remaining particles were heated with a focused 200 μm of diameter laser beam. Laser emission was stopped when no more reaction to the laser beam occurred. Some residues remained for the diatom subsamples. They decreased from KYO 40 to KYO 90. These protocols prevented ejecta.

The liberated oxygen was then purified and trapped by adsorption in a microvolume filled with 13X molecular sieve and cooled in liquid nitrogen. The oxygen gas was then heated at 100 °C and directly sent to the sample bellow of the dual-inlet mass spectrometer (ThermoQuest Finnigan Delta Plus).

In order to get a sufficient 34/32 signal (2−3 V), the oxygen from 0.3 mg aliquots was concentrated in the mass spectrometer in an autocooled 800 μL microvolume filled with silica gel and directly connected to the dual-inlet system.


Cool I think, at least if you think a certain way. Analytical inorganic chemistry can be very beautiful.

I wish you a happy and prosperous New Year.

Bill Clinton's book review of Chernow's "Grant."

I have long felt that the Presidency of Ulysses S. Grant, often rated by academic historians as disastrous and failed, needs serious reassessment, which happily is now going on, particularly at a time when we have a "President" who is actually worse than Andrew Johnson, one of the worst Presidents ever, who was impeached but not convicted.

I happen to believe that Ulysses S. Grant was a great President, the second most important President of the 19th century, responsible for one of the most important and necessary changes to the US Constitution, the 15th amendment, which happily was recently responsible for the election of Doug Jones in Alabama.

It is very unlikely that the country would have survived at all without Grant's Presidency; without him the Union victory in the Civil War would have been undone as the country lapsed into continuous guerrilla warfare.

The reassessment of the Grant's Presidency is well underway - the low ranking having been fostered on historians by an odd coalition of overt racist "lost cause" advocates and self described "reformers" - and is being advanced at an increasing pace, something that satisfies me personally very much, as I have long admired President Grant.

I wrote about my admiration of Grant elsewhere a long time ago: US Grant and the Worst President Stuff (2007)

The second President to be impeached but not convicted, and who was actually quite a good President, is of course, Bill Clinton, and interestingly, he has reviewed Ron Chernow's best selling book on the 18th President of the United States.

NY Times Book Review of Cherow's "Grant" by Bill Clinton

Clinton writes:

The Union that Grant had been instrumental in saving as a general was splintering anew even before he took his oath of office. As Chernow writes, “If there were many small things Grant didn’t know about the presidency, he knew one big thing: His main mission was to settle unfinished business from the war by preserving the Union and safeguarding the freed slaves.”

And there was a very real chance Grant, and with him the country, would fail.

For that new mission, Grant needed cabinet members, staff and advisers every bit as masterful as his wartime lieutenants. His choices were notably hit-and-miss, but his very first appointee from a Confederate state proved to be one of his best. Amos T. Akerman of Georgia, Grant’s second attorney general, was “honest and incorruptible” and “devoted to the rule of law.” When Congress created the Department of Justice the same week as his appointment, the attorney general became overnight the head of “an active department with a substantial array of new powers.” Those powers were sorely needed to fight the Klan and what Chernow appropriately calls “the worst outbreak of domestic terrorism in American history.”...

...Chernow shows a fine balance in exposing Grant’s flaws and missteps as president, and the ill-fated turn that Reconstruction took after a promising start, while making it clear that Grant’s contributions after Appomattox were as consequential to the survival of our democracy as any that came before. As Americans continue the struggle to defend justice and equality in our tumultuous and divisive era, we need to know what Grant did when our country’s very existence hung in the balance. If we still believe in forming a more perfect union, his steady and courageous example is more valuable than ever.


I almost agree.

Anyway.

In these times where racists are running wild in the Government, where corruption at a very high level is taking place, where the Government is being bankrupted by wealthy scammers and their collaborators, I think Chernow's book is very important.

I've asked Santa to buy it for me, and will be waiting up all night at the Christmas tree to yank that book out of the fat Elf's sack.

Accumulation of a very potent greenhouse gas has stopped.

Recently I was going through some papers I downloaded on the subject of the gas oxygen difluoride, OF2, which is of interest to me because of some ideas I've had about electrochemical/fluoride volatility approaches to the recovery of valuable materials from used nuclear fuels, specifically the elements ruthenium, rhodium, technetium, molybdenum, plutonium, neptunium and uranium.

To my surprise, one of the papers found by my Google scholar search and collected by me was this one: Identifying the Molecular Origin of Global Warming (Lee, Berra and Francisco, J. Phys. Chem. A, 2009, 113 (45), pp 12694–12699) which, it seemed to me, has nothing to do with nuclear fuel reprocessing or even the chemistry of OF2.

But for some reason, the gas OF2 appears in table 1 the paper with a list of gases with global warming potential, their atmospheric lifetimes, global warming potential, etc.

The atmospheric lifetime of OF2 is not listed, which is not surprising, it should be as close to zero as it can be without actually being zero. OF2 is one of the few molecules known in which a positive charge resides on the extremely electronegative atom oxygen. As such it is one of the most powerful oxidants known; it will rapidly and quantitatively oxidize water: OF2 + H2O -> 2HF + O2.

Possibly it was included because it is a powerful fluorinating agent and thus may be utilized in the production of some of the gases that are utilized to make gases like the perfluoroalkanes and hydrofluoroalkanes (HFCs) that have replaced ozone depleting chloroflouroalkanes (CFCs) banned under the Montreal Protocol in refrigeration systems, HFC's being gases that are not ozone depleting but are nonetheless global warming forcing gases.

Otherwise, almost all of the other gases in the table were familiar to me, varieties of the aforementioned CFC's and HFCs, nitrous oxide, N2O (a potent ozone depleting gas as well as a global warming forcing gas), SF6 which replaced polychlorobiphenyls (PCBs) in electronic equipment as is also used in "green" thermally insulating windows in "environmentally aware" McMansions and office buildings meeting LEED certifications...blah...blah...blah.


In contrast to the situation with oxygen, most bonds to fluorine are extremely stable, notably in the case of carbon fluorine bonds, nitrogen fluorine bonds and sulfur flourine bonds, and as a result these compounds can persist for a very long time and are only destroyed by exposure to high energy radiation, far UV, x-rays and gamma rays.

Then there in table 1 was one gas of which I'd never heard, and about which I knew zero, pentafluorosulfuryltrifluoromethane, SF5CF3.

I asked myself, what the hell is that and why is it there and what the hell do they use that for?

In the table, it is listed as the most potent global warming potential gas, said potential being 22,800 on a scale in which the dangerous fossil fuel waste carbon dioxide is defined as having a value of 1.

As for "what the hell do they use that for?" the answer is, apparently, "nothing." The gas was discovered in atmospheric samples in Antarctica in the year 2000 and reported in the journal Science: A Potent Greenhouse Gas Identified in the Atmosphere: SF5CF3 (Sturges et al Science ol. 289, Issue 5479, pp. 611-613) Since there was no known use for the gas, the authors speculated that the gas was being created in the high field electronic equipment in which SF6 was utilized by reaction with teflon components. (The HTML version of the paper is open sourced, the PDF is not.)

It turns out that the authors were wrong and cheerfully admitted as much: Emissions halted of the potent greenhouse gas SF5CF3 (Sturges et al, Atmos. Chem. Phys., 12, 3653–3658, 2012) This paper is also open sourced as a PDF, but I'll excerpt it anyway.

Immediately following publication of our article, however, an open letter to the publishing journal from the company 3M stated that “one source of this compound is as a by-product of the manufacture of certain 3M fluorochemicals” (Santoro et al., 2000). It transpired that the relevant process was electrochemical fluorination for the production of perfluorooctanyl sulphonate, (PFOS) and other fluorosurfactants, used in the manufacture of foams and stain-resist coatings.

They went on to note that these production operations were to be imminently curtailed in the USA. In a subsequent personal communication, their bottom-up emission estimates were evidently close to the global emission rate that we had deduced from observations. We have updated the time series of atmospheric measurements from our original publication, and find that SF5CF3 has ceased to increase in the atmosphere, whereas the abundance of SF6 has continued to rise unabated. This clearly demonstrates that our original supposition that SF5CF3 originates from the degradation of SF6 was incorrect, and that all evidence now points to 3M being correct in their earlier assertion and that, as they predicted, emissions of this greenhouse gas have subsequently reduced to the point where they are no longer distinguishable by observation from zero.


PFOS is a serious persistent pollutant in its own right with a seriously long lifetime. I have written quite a bit about this compound which is also only degraded by high energy radiation, more or less, although some metabolism into potentially worse pollutants has been observed. PFOS can be pretty much detected in every living thing on the planet, particularly in lipids. 3M sold it until early 2000 in the product Scotch Guard which was very popular for protecting furniture.

(Other very persistent pollutants are also related to furniture as well, the flame retardants known as PBDE's, polybromodiphenyl ethers: These are also being phased out in furniture and clothing. They are also highly stable and only degraded radiochemically.)

To the credit of 3M, once they became aware of the persistence problem they voluntarily stopped making the product, which was a big seller, rather than manufacture ersatz "science" proving it was harmless - the Exxon approach.

They also immediately and voluntarily "'fessed up" about the source of SF5CF3, as noted by authors.

It does seem, happily, that this gas will not be growing in the atmosphere, even if most greenhouse gases will continue to rise unabated because, basically, we just don't care.

Have a happy holiday season.

Have you considered the meaning of the word "worthy?"

One of the great pleasures in life is to read and re-read the works of the great historian David McCulloch, and one of his greatest books of course is John Adams. (The HBO film series based on it is also excellent.)

I was leafing through it this morning and came across this excerpt of a letter from Adams, late into his retirement, to his grandson John Smith and in these awful times bears repeating:

Have you considered the meaning of the word "worthy?" We it well...I had rather you should be a worthy processors of one thousand pounds honestly acquired by your own labor and industry, than of tens of millions by banks and tricks. I should rather you be worthy shoemakers than secretaries of states or treasury acquired by libels in newspapers. I had rather you should be worthy makers of brooms and baskets than unworthy presidents of the United States procured b intrigue, factious slander and corruption.


(cf, David McCulloch, John Adams, Simon and Schluster, 2001 pg 608-609)

The bold is mine, but is actually apropos to the present state of affairs, one of the darkest periods in American history through which I've lived, and I lived a long time.

Franklin Roosevelt had these words, written by his predecessor Adams inscribed on the mantle of the fireplace of the White House"

"May none but Honest and Wise Men ever rule under This Roof."


This has obviously failed to be true, and the White House is actively being defiled by a racist pig who obviously can neither think, read or reflect. If he ever bothered in his sneering ignorance to read these words - he would simply continuing sneering at his country using his well known contempt for humanity and his country.

Both Presidents must be rolling in their graves.

A critical issue of critical materials; my holiday science reading list.

I have 10 glorious days off from paid work this holiday, and plan to catch up on some reading for which I've had little time.

One important task will be to write to an on line friend about what I've learned about her great niece's diffuse intrinsic pontine glioma, a very dangerous (and rare) pediatric brain cancer which has been the subject of considerable research.

It's frightening, but I believe I'm an old Obama boy; I believe in hope. I'll do what I can to be of any help.

Another is to catch up on some reading about the broader challenges to humanity beyond any individual beautiful and threatened child.

Tonight in my files, I came across a highly cited paper which I have not read; it's on my holiday reading list, this one:

What Do We Know About Metal Recycling Rates? (Graedel et al, Journal of Industrial Ecology Volume 15, Issue 3 June 2011 Pages 355–366)

A few years back, around this time of year, I came across an interesting (if unappreciated) book in the New Books rack in Princeton University's Engineering Library, a sort of shrine that I visit often on my path to peace. It's this one: Thanatia

The above cited paper was in fact a reference from this book.

Thanatia s a little rapped up in this Gaia/not Gaia sort of touchy feely stuff, but I think a somewhat poetic description of a critical issue about which too little public discussion takes place.

The preface of the book, which is now in my files, states issue it addresses quite well:

The extraction of fossil fuels and mineral resources has grown exponentially since the early 20th century and far from decelerating, it is expected to increase in the coming decades. "The Limits to Growth" (Meadows et al., 1972) already alerted that if demand of metals and fossil fuels maintained the same trend, mankind would sooner or later be close to collapse. The book provoked a strong controversy between those that considered that the Earth was plentiful of non-renewable resources (technooptimists) and those who believed in the need for a rational management of the planetary mineral endowment.

Forty years on society has experienced an unparalleled economic optimism (especially in the nineties and the first few years of the 21st century) and also the biggest economic crisis since the Wall Street crash in 1929. At the same time, computers, smartphones, the electric car, renewable energies, new materials and electronic appliances are renovating the optimism for a brighter future. Yet all these technoartifacts are deeply connected to the mineral endowment of the Earth. Elements like indium, gallium, germanium, rare earths, tantalum, zirconium, cobalt, tin, precious and platinum group metals, lithium, tellurium, phosphorous, etc, are profusely used without or with only minor recycling.

How long can society survive without a rational management of these scarce resources? Today, technology is employing all elements of the periodic table and their use is growing exponentially.-Yet this fact is barely discussed in conventional ecological discourse that preferably focuses on climate change, loss of biodiversity, deforestation or ecosystems destruction.


I am, even if I believe that the popular beliefs about sustainability are actually dangerously wrong headed - as much on the left as on the right - still a kind of "techno-optimist." I once spent an afternoon chatting with Freeman Dyson after all.

But as much as in my techno-optimism I believe that dire and extreme problems can be solved, I'm less and less inclined to have faith that they will be solved.

The Christmas season in the United States is a party time: I will participate. But there is some place in it as well, for me if not for everyone, for some sobriety.

Have happy holidays and if you can squeeze in some time, read some science. It's good for you, far better than egg nog.


A Nice Discussion of the Use of Desalination Brines for the Production of Caustic Soda (NaOH).

Many years ago, in this space, back when I was still a fan of so called "renewable energy," I wrote a brief discussion of the potential use of California's Salton Sea as a tool for energy recovery and desalination.

That post is here: I offer a crazy energy idea about which I've fantasized: The Salton Sea.

Many of my energy ideas have changed since I wrote that piece 12 years ago. This was, for example, before the planetary community invested trillions of dollars in so called "renewable energy," dominated by the useless solar and wind industries.

In November of 2005, the mean concentration of the dangerous fossil fuel waste as reported at the Mauna Loa carbon dioxide observatory was 378.29 ppm. In November of 2016, the most recent posted monthly mean posted there, the concentration was 405.14 ppm.

The average for all year to year monthly comparison figures recorded as increases in the 20th century was 1.30 ppm/year. Since November of 2005 to November of 2017, the same type of average is 2.24 ppm/year.

So called "renewable energy" is a grotesque failure. It has not worked; it is not working; it will not work, if the goal is to address climate change rather than to post "feel good" stuff on the internet about how wonderful solar and wind are and how wonderful it is to subsidize the billionaire Elon Musk to the tune of billions of dollars because he's so, um, "green."

However this may be, and however much I may have changed my mind about so called "renewable energy" since 2005, I am still very concerned about our absolute indifference on this planet to address climate change. Now, as the end of my life approaches filled with existential guilt about what my generation is leaving for future generations, I am very much trying to spend some portion of my time to thinking about ways to remove carbon dioxide from the atmosphere, in other words, how future generations might, to whatever extent possible, clean up the planetary superfund site with which we've left them.

Once consequence of climate change will almost certainly involve access to clean and fresh water. We have seen this in many places on this planet, most graphically and recently for those Americans who give a shit - this would leave out anyone involved with the Trump crime family - in California, where I used to live decades ago, and where I used to think all the time about water.

It does seem to me that the only approach to addressing this issue in places like California, and for that matter in places where water supplies depend on glaciers, which they do for billions of people will involve seawater desalination.

Desalination is not, in any way, environmentally benign, however. One of the most important issues involved is of course, energy. Unless clean carbon free sustainable energy is available - I never tire of pointing out that in my opinion only nuclear energy meets this criteria - all desalination schemes will be counter productive.

The other problem with desalination concerns the resulting brine. Most schemes for desalination return the concentrated brine directly to local waters. On a grand scale this has the potential for further environmental destruction not only because of the impact on local ecosystems, but also on the further destabilization of oceanic salt gradients, which in turn further destabilize climatic and temporal weather.

Although I still favor, for certain reasons, the same thing I proposed in 2005 for the Salton Sea, formally reduced pressure distillation, over all in the scientific literature, at least in my overall impression, much of the discussion has focused on membrane separation.

A very nice overview of a potential solution for the brine problem (with some impact on the energy problem as well) was recently published in the wonderful scientific journal ACS Sustainable Chemistry and Engineering by scientists out of MIT.

The paper is here: Utilization of Desalination Brine for Sodium Hydroxide Production: Technologies, Engineering Principles, Recovery Limits, and Future Directions (John Leinhard V, et al, ACS Sustainable Chem. Eng., 2017, 5 (12), pp 11147–11162)

All of the energy ideas I've had in my lifetime involve the utilization of by products of processes - often referred to as "waste" in our common parlance - as starting materials or tools to accomplish other tasks. (Mostly this involves material by products but also can include heat.) This is why this paper so pleases me. It proposes to use a waste product (brine) to make another value added product (caustic soda, NaOH).

The introduction to the paper addresses this nicely:

Environmental and economic factors have long motivated interest in reducing the amount of brine discharged back into the ocean by seawater desalination plants. Modern designs for brine outfalls can limit adverse environmental impacts to “tens of meters” from the discharge source(1, 2) but are high cost.(3) An emerging class of solutions, broadly titled waste-to-resource, aim to reduce brine discharge by transforming it into useful compounds.(4-7)

Many previous such studies focus on recovering salts, of which the largest by mass is sodium chloride. But in many countries, NaCl exists in abundant, cheap supply as rock salt or brine, meaning any competing source must be extremely low cost. [The US Geological Survey reports average US rock salt and brine prices ranging from 38–50 USD/ton and 8–9 USD/ton, respectively, from 2011–2015.(8)] Its chemical derivatives, primarily soda ash, caustic soda (“caustic”), and chlorine, however, may be much higher value. Nearly 30% of NaCl sold in the US(8) is used as a feedstock in the chlor-alkali process to manufacture the most common of these at large scale: NaOH and Cl2. Also, NaOH is frequently used within the desalination plant itself.

Consequently, producing NaOH from seawater reverse osmosis (SWRO) brine for reuse within the SWRO facility has the potential to benefit environment and plant economics. By replacing NaOH manufactured off-site using chlor-alkali by an on-site, lower-energy process (e.g., one producing HCl as a byproduct instead of Cl2), the environmental and economic footprints of NaOH generation and transport are reduced. By diverting a portion of the brine discharge, less salt flows into the ocean, resulting in lower salt concentrations around brine discharge ports, which lessen the plant’s impact on marine life. Further, since both benefits scale with the amount of NaOH produced, any other nearby consumers of the NaOH produced would serve to increase the positive environmental and economic impacts of this technology.


In the following text, the authors point to the use of NaOH within a desalination plant, albeit in this case of a "SWRO" plant (Seawater Reverse Osmosis) plant.

They write:

Caustic soda has myriad uses both internal and external to the desalination plant. Internally, treating seawater feed with caustic soda increases the pH. At higher pH, several compounds are better rejected by the RO membrane. Around pH 9, the better-rejected borate anion B(OH)4– supplants boric acid as the dominant aqueous boron species.(11) The dissolved silica system behaves similarly, with the dominant SiO(OH)3– and SiO2(OH)22– species above pH 9 yielding better silica rejection,(12) and above pH 8, dissolved inorganic carbon exists as bicarbonate and free carbonate, which are better rejected than aqueous carbon dioxide.(13) Evidence also shows reduced organic fouling at high pH.(14) Finally, caustic soda is an ingredient in cleaning solutions to remove organic, biological, and organic/inorganic colloidal foulants and silica scale.(15)

For internal reuse, caustic soda purity requirements are moderate. Membrane manufacturers manuals for reverse osmosis(16) rate technical grade as sufficient purity for membrane and system compatibility.


I should point out at this point that while this situation applies to SWRO plants, NaOH would be useful in brine resulting from other processes. In particular it might prove of great utility in the recovery of certain metals from seawater, notably magnesium and calcium (but also including others) and another constituent of prime importance which is much more concentrated in seawater than it is in the atmosphere, carbon dioxide, along with certain carbon compounds. This would, however, probably involve a huge scale up of NaOH production, although there are some very cool approaches to in situ partitioning of seawater into HCl and NaOH fractions which I have no time to discuss here.

The authors further discuss the economic importance and current production methods for the production of sodium hydroxide:

n addition to its use in controlling pH and neutralizing acids, caustic soda is used as a reagent in the production of many chemicals. About 59% of NaOH in the EU and North America is used in the pulp and paper, inorganic, and organic chemical industries.(19) Soaps and detergent manufacture also account for significant demand. For external reuse, quality requirements are application specific, and some commercially produced caustic soda is of insufficient purity for certain industries. For example, caustic soda produced using the diaphragm process is not suitable for manufacturing viscose, also known as rayon.(20, 21)

Industrial production of caustic soda is massive. Global manufacture exceeded 59 million tons in 2004,(19) with significant growth in demand and capacity expected in Asia.(20) Production is also scalable, with plant capacities ranging from about 4.4 kt/yr (Kapachim, Inofita Viotias, Greece) to 1744 kt/yr (Dow, Stade, Germany) in the EU(22) and about 2 to 3333 kt/yr (Olin, Freeport, TX) in the US(20, 23) on a dry basis. [Estimated from chlorine capacity at 1.1 kt NaOH/kt chlorine,(18) which is slightly less than stoichiometric.] On the small end, ThyssenKrupp Uhde GmbH offers standardized skid-mounted plants at up to 17 kt/yr, and AVS Technology AG offers plants as small as 1.1 t/d.

About 99.5% of global caustic soda production is by the chlor-alkali process.(24) Briefly, the process produces caustic soda and chlorine gas in equimolar amounts by electrolysis of aqueous sodium chloride. Direct synthesis of process products can also produce hydrochloric acid, though less than 10% of HCl is manufactured this way.(25) (Technical aspects of the chlor-alkali process and other methods are discussed in-depth below.) Three variants of the process exist in widespread commercial use, generally distinguished by how catholyte and anolyte are separated. The variants are known as the membrane, diaphragm, and mercury processes.


The authors then discuss that the chlor-alkali process produces equal molar amounts of chlorine gas and NaOH and that the demand for these two commodities is not always matched, even if some of the chlorine is diverted to make another commodity, HCl, hydrochloric acid. (Hydrochloric acid is often a waste product needing disposal. There are huge waste disposal issues with it, and one dubious approach to dealing with it has been deep welling it.)

This mismatch has lead to wide fluctuations in the price of NaOH, as a graph from the paper shows:



It is worth noting that the "mercury process" - which is happily being phased out - has resulted in a large contribution to the widespread contamination of the environment with mercury. Although the amount of mercury from this source is definitely dwarfed by mercury contamination deriving from coal exhaust, fly ash and ash, it is still significant.

(Sometimes I think the whole world is developing "mad hatter disease." How else can we account for the placement of incredible fools like the orange nightmare in the White House, and his foreign equivalents, Kim Jung Un, Rodrigo Duarte, Recip Erdoğan, to name just a few.)

The authors graphically show the current chlor-alkali processes industrially in use:



The rest of the article is involved with thermodynamic and the always related economic issues, along with some technical arguments connected with membrane technology (which is the focus of the paper.)

Also discussed is heat, which is also an issue in the reduced pressure schemes about which I often privately muse.

Overall, I like these kinds of papers and I thought I'd share this one for anyone who may find it interesting. Interested readers who can manage access, are invited to look the paper up.

Esoteric I know, but important.

Enjoy the coming work week.


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