If you missed my comment edit, it's a lot less clear than I initially thought. Per Derek Lowe's blogpost, the ClO_x species supposedly don't migrate into the vapor phase. They're a component of the liquid fuel, but wouldn't necessarily end up in the exhaust.
- "...This mixture spontaneously ignites under the decomposition conditions, but it does not thermally decompose the underlying liquid. Meanwhile, at the anode, the perchlorate gets oxidized to chlorate and chlorite ions, but none of that shows up in the gas phase."
None of the credible end products are good, though.
Perchlorate itself is at least somewhat toxic. Chlorate and chlorite are, too, and efforts are made to reduce the amount in drinking water.
Chloride is relatively innocuous (people need quite a bit to be healthy), although it’s not great when it gets on metals due to corrosion issues. Bit chloride doesn’t exist by itself — it needs to be balanced by a positive charge somewhere.
So that leaves HCl? Hydrogen chloride gas is fairly nasty.
The best outcome I can think of for automotive use is to carry around a bunch of calcium carbonate, AdBlue style, and try to arrange for the end products to be CaCl and CO2, and to declare that this is somehow a good thing because the cars all emit a steady drip drip drip of deicing fluid.
Because the only actual problem in EVs is making a better battery. They solve a bunch of other problems. Far fewer moving parts, better packaging, massive gains in pure energy efficiency, no smog, a direction for Zero emissions. The Internal combustion engine, as someone who has owned multiple Manual Mazda Miatas, is seeing the end of it's times. It's a dead end in almost every situation. Additionally, this has none of the gains that are actually desired, they want efficiency and less emissions. Not chlorine gas.
Edit:
To be clear, I'm talking about Gasoline ICE applications in the context of this article, which is far more narrow than all of combustion. Most ICE applications that are not ground transport are Diesel, which is not applicable to this. This is not applicable to jet fuel. Most small engines (lawn care) are rapidly being replaced with electric power as well.
Combustion engines are still the only viable option for long-range, large-scale heavier-than-air flight, for marine transport (on oceans, and most lakes, rivers, and canals), for many mobile power operations ranging from handheld tools to remote power generation, and for much overland heavy cargo transport (trucks, much rail).
Some of those can be electrified, but there are likely always to be exceptions in which that is not possible. Electrification is most viable where usage is heavy. Tracked vehicles electrify more easily than road-based ones (though yes, trolley busses are in fact A Thing). Canal traffic can be electrified through use of onshore "mules" (electrified traction), though passing and overtaking become concerns. River and lake traffic is less suited to this (again, possible in cases but not entirety).
High-latitude sites as in Siberia, Alaska, Northern Canada, and Antarctica cannot rely on solar power, and would require either a fuel-based or nuclear-based generating capacity. (McMurdo Station on the Antarctic coast had a nuclear plant, that didn't go so well.)
Mind that not all of these uses have a high demand for low-flammability fuels, which applies most specifically to aircraft. But all tend to rely strongly on fuel-based energy systems, and substituting for those is exceedingly challenging. The alternatives are effectively:
- Continue use of fossil-based hydrocarbon fuels.
- Find an alternative non-fossil hydrocarbon fuel analogue. There's been interesting work, and commercial industrial creation, of synfuels dating to the 1940s, though that was coal-to-oil conversion in Germany and South Africa. Generating fuels from CO2 sourced from seawater or the atmosphere has been researched since the 1970s at M.I.T. and the U.S. Naval Research Lab (USNRL), with technical proof but to date no commercial success. Google's X Labs attempted commercialisation under Project Foghorn, but failed on economics: <https://x.company/projects/foghorn/>
(I've reasons to argue that it's the economics of fossil fuels, not synfuels, which is principally to blame here.)
(Biofuels are often suggested. The problem here is that the net likely capacity is at best a small fraction of present fossil fuel usage. We might feed 5--10%, with the upper bound being highly optimistic, but we're not going to replace 100% of present fossil fuel usage, let alone the future growth required to bring under-developed regions of the world to even a small fraction of industrialised nations' consumption.
- Substitute non-combustion energy plants. To date that's nuclear, which ... has its own challenges. For larger fixed-site locations, that's possibly viable, though there are numerous cautionary tales to heed. For mobile applications such as rail or marine transport, the compounded risks of already probable accidents make this highly unattractive.
- Substitute renewables. The prospect of resuming sailing ships for international sea cargo is floated, though cost and scale of ships would likely be impacted (rising and falling, respectively) tremendously.
- Drastically curtail or cease such activities. One of the realities of economics is that as expressed costs change, so too do activities in which those costs are incurred. The fossil fuel age has made transportation unbelievably inexpensive compared to pre-industrial times. It's possible that we'll see considerable back-sliding on both personal and cargo transportation as fuel costs rise. This will of course profoundly re-shape the world, in much the way that cheap transportation re-shaped in our recent past.
There will continue to be uses for gasoline and similar, but the usefulness of an engine relates to the availability of the fuel. Making a new kind of engine that runs on a new kind of fuel is somewhat of a dead end unless you're 1) envisioning a niche application or 2) expecting a wide take-up. But people are largely switching away from combustion engines, and synthetic fuels seem to work fine for the remaining ones. So I think we're going to end up with gasoline, diesel, and jet fuel compatible engines, not whatever this stuff is.
For those who don't pay much attention to ionic liquids, 1-butyl-3-methylimidazolium, or "bmim", is one of the most common — if not #1 — ionic liquids used in organic chemistry. This property is rather unexpected, but the compound is not itself new or unusual.
As for the perchlorate anion, it's a little surprising, but given the cost of bmim (which is unlikely to come down), I don't think the authors expect it to be cost-effective outside of safety-critical environments where a fume hood could be employed.
Yes. Diesel fires are pretty rare. If a diesel truck crashes on the highway, the biggest risk is to the environment (it's pretty toxic), and to the road (diesel dissolves asphalt).
Never thought about the asphalt part, but makes some sense. From what I understand, bitumen is basically the part of oil distillation left over after you distill away all the aromatic(liquid) stuff.
Kerosene is also very safe. Pprune is full of stories of technicians throwing burning cigarettes in kerosene to extinguish them (and to scare novice pilots)
Combustion is a function of surface area, fuel/air temperature, mixing, oxygen supply. If you were to vaporize this fuel in a hot, high-oxygen environment, it would burn, like pretty much any other fuel.
The title is a little misleading, the fuel is most certainly not fire-safe. It is, after all, a fuel. A better title might be "Scientists vaporize ionic combustion fuels using an electric current".
I suppose it is slightly misleading, but it still could be true for many intents and purposes. For instance, a fire marshal once explained that kerosene had a much higher temperature of evaporation than gasoline. You could put a cigarette out in the first but not the second. That can make a big difference even though kero will start on fire pretty quickly in other circumstances.
Here's a question: what criteria would a substance need to meet in order to be properly termed a fire-safe fuel? I'm thinking that for combustion fuels, fire-safe fuel may be a contradiction in terms, where no such criteria could be written.
So I looked it up. This group [a] had concerns about this ionic liquid class, because of the perchlorate, and they tried standardized impact- and friction- sensitivity tests. They looked at 1-ethyl-3-methyl-imidazolium perchlorate, [emim][ClO4]. The ionic liquid in OP is 1-butyl, [bmim][ClO4].
"Stability of [emim][ClO4]: With respect to the hazardous nature of organic perchlorates, we tested the stability of I according to the UN Test Series UN 3a to UN 3d..."
Here's their conclusion :
- "Despite being relatively stable against mechanical stress, the friction test leads to the conclusion that I has to be categorized as a hazardous explosive material. Therefore, I would not become a commonplace ionic liquid like [emim][NTf2]."
So, you apply a voltage to the fuel to produce gas by electrolysis, and then you ignite the gas. But, if you apply voltage and produce a sufficient amount of gas before igniting it, you could still trigger a pretty big explosion, right?
Readit News
(Also, what the fuck, this is a chlorine compound, as perihelions points out. WTAF.)
- "...This mixture spontaneously ignites under the decomposition conditions, but it does not thermally decompose the underlying liquid. Meanwhile, at the anode, the perchlorate gets oxidized to chlorate and chlorite ions, but none of that shows up in the gas phase."
https://www.science.org/content/blog-post/instant-flames-saf...
Perchlorate itself is at least somewhat toxic. Chlorate and chlorite are, too, and efforts are made to reduce the amount in drinking water.
Chloride is relatively innocuous (people need quite a bit to be healthy), although it’s not great when it gets on metals due to corrosion issues. Bit chloride doesn’t exist by itself — it needs to be balanced by a positive charge somewhere.
So that leaves HCl? Hydrogen chloride gas is fairly nasty.
The best outcome I can think of for automotive use is to carry around a bunch of calcium carbonate, AdBlue style, and try to arrange for the end products to be CaCl and CO2, and to declare that this is somehow a good thing because the cars all emit a steady drip drip drip of deicing fluid.
Edit: To be clear, I'm talking about Gasoline ICE applications in the context of this article, which is far more narrow than all of combustion. Most ICE applications that are not ground transport are Diesel, which is not applicable to this. This is not applicable to jet fuel. Most small engines (lawn care) are rapidly being replaced with electric power as well.
Some of those can be electrified, but there are likely always to be exceptions in which that is not possible. Electrification is most viable where usage is heavy. Tracked vehicles electrify more easily than road-based ones (though yes, trolley busses are in fact A Thing). Canal traffic can be electrified through use of onshore "mules" (electrified traction), though passing and overtaking become concerns. River and lake traffic is less suited to this (again, possible in cases but not entirety).
High-latitude sites as in Siberia, Alaska, Northern Canada, and Antarctica cannot rely on solar power, and would require either a fuel-based or nuclear-based generating capacity. (McMurdo Station on the Antarctic coast had a nuclear plant, that didn't go so well.)
Mind that not all of these uses have a high demand for low-flammability fuels, which applies most specifically to aircraft. But all tend to rely strongly on fuel-based energy systems, and substituting for those is exceedingly challenging. The alternatives are effectively:
- Continue use of fossil-based hydrocarbon fuels.
- Find an alternative non-fossil hydrocarbon fuel analogue. There's been interesting work, and commercial industrial creation, of synfuels dating to the 1940s, though that was coal-to-oil conversion in Germany and South Africa. Generating fuels from CO2 sourced from seawater or the atmosphere has been researched since the 1970s at M.I.T. and the U.S. Naval Research Lab (USNRL), with technical proof but to date no commercial success. Google's X Labs attempted commercialisation under Project Foghorn, but failed on economics: <https://x.company/projects/foghorn/>
(I've reasons to argue that it's the economics of fossil fuels, not synfuels, which is principally to blame here.)
(Biofuels are often suggested. The problem here is that the net likely capacity is at best a small fraction of present fossil fuel usage. We might feed 5--10%, with the upper bound being highly optimistic, but we're not going to replace 100% of present fossil fuel usage, let alone the future growth required to bring under-developed regions of the world to even a small fraction of industrialised nations' consumption.
- Substitute non-combustion energy plants. To date that's nuclear, which ... has its own challenges. For larger fixed-site locations, that's possibly viable, though there are numerous cautionary tales to heed. For mobile applications such as rail or marine transport, the compounded risks of already probable accidents make this highly unattractive.
- Substitute renewables. The prospect of resuming sailing ships for international sea cargo is floated, though cost and scale of ships would likely be impacted (rising and falling, respectively) tremendously.
- Drastically curtail or cease such activities. One of the realities of economics is that as expressed costs change, so too do activities in which those costs are incurred. The fossil fuel age has made transportation unbelievably inexpensive compared to pre-industrial times. It's possible that we'll see considerable back-sliding on both personal and cargo transportation as fuel costs rise. This will of course profoundly re-shape the world, in much the way that cheap transportation re-shaped in our recent past.
For those who don't pay much attention to ionic liquids, 1-butyl-3-methylimidazolium, or "bmim", is one of the most common — if not #1 — ionic liquids used in organic chemistry. This property is rather unexpected, but the compound is not itself new or unusual.
As for the perchlorate anion, it's a little surprising, but given the cost of bmim (which is unlikely to come down), I don't think the authors expect it to be cost-effective outside of safety-critical environments where a fume hood could be employed.
The title is a little misleading, the fuel is most certainly not fire-safe. It is, after all, a fuel. A better title might be "Scientists vaporize ionic combustion fuels using an electric current".
It's amazing how we live through our teenage years sometimes.
[a] https://sci-hub.se/https://doi.org/10.1002/ejic.201100529
"Stability of [emim][ClO4]: With respect to the hazardous nature of organic perchlorates, we tested the stability of I according to the UN Test Series UN 3a to UN 3d..."
Here's their conclusion :
- "Despite being relatively stable against mechanical stress, the friction test leads to the conclusion that I has to be categorized as a hazardous explosive material. Therefore, I would not become a commonplace ionic liquid like [emim][NTf2]."
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