The missing puzzle piece appears largely to be one of the *confinement* of such reactions. The highly unconsolidated (albeit homogeneous) nature of the sawdust oxygen mixture allows the mass to disassemble itself in a weak deflagration analogous to a pile of black powder on a table being ignited. When confined in a rigid container however, (possibly only even in a glass cold trap) both mixtures absolutely will detonate violently.
Yeah with confimenment you can certainly make it more dangerous, but I was not to keen on experimenting with that and getting accused of bomb building. XD
it does, nitroglycerin will actually just puff into smoke but there are stories of people using c4 instead of a portable solid fuel for cooking MREs in the army, its one of the few things the mythbusters did that really really shocked me, cant find the mythbusters episode but there are some vids on yt @@Boomchacle
The actual danger of liquid oxygen is saturating stuff you don't want to burn, like clothes on your body, with it without noticing and then being turned into a human blow torch so quickly you can't react to it before being covered in 3rd degree burns because of static discharge.
Static discharge is actually really bad at lighting this, but if you get very unlucky anything can be really dangerous. I guess driving a car is generally a lot more dangerous.
@@EliasExperiments The thing is, oxygen saturated clothing means that if another thing goes wrong, it goes really, really, REALLY wrong, as in, the life you had before the accident is over. In other words, if there is a 1 in 100000 chance you turn into a human flare, will that number comfort you when you're in a burn ward after the freakest accident actually happens? Comparing it to car accidents doesn't really fit if you consider the billions of dollars worth or R&D spent to make cars and roads safer because humans are easily distracted monkeys with ego problems. Also, a dismissive attitude about safety - even jokingly - has claimed many lives of those who thought it couldn't happen to them. Wood burning microwave transformers come to mind - total widowmakers.
So I am perfectly aware that what I did in this video could have gone horrible wrong. The thing is anything you do in live can go very horribly wrong. You can't have no risk in life. If you don't do anything to avoid making mistakes you will probably regret it at the end of your life and that would be a horrible tragedy in itself. Why can I not compare it to car accidents? Should I compare it to extreme sports, or overeating, or what would you prefer? No matter what you do tragedy and horror lurks everywhere. If you have a solution to safely avoid tragedy I would love to hear it. I am by no means dismissive about safety. I am dismissive about a wrong perception of reality and not putting actions into proper perspective. Like this video vs. car driving, extreme sports, overeating etc. There are always two extremes: Being safe and being completly irresponsible are two nice opposites. However being on the safety extreme it no good either in my opinion. I think it is far better to learn how to deal with dangerous stuff instead of trying to hide from it. That would be the lesson of sleeping beauty ;-) So how about you pick your poison, I will chose mine? ;-)
@@EliasExperiments It’s just good to be aware of what the dangers are. Your clothes were in a plume of concentrated oxygen vapor when trying to cool that propane. Maybe it would be better to just use nitrogen when trying to cool something. That pan of wood dust had potential to blow violently if there was a slightly different amount of oxygen, or different mixing or type/point of ignition. The propane thing managed to blow up just from a flame in an open container. Most things that do that are things you don’t want to stir or shake by hand.
@@EliasExperiments I guess the point is, there’s little moments of danger that aren’t as obvious as what you would see when driving. I probably missed a lot more than I noticed. Just because something like this worked 11 times doesn’t mean it will work safely the 12th.
Im a pyrotechnician from germany and i think i have a valuable comment: in my experience things that combust in a harmless manner when unconfined can make a surprising boom when confined. When the hot gases cant escape temperature and pressure build, im sure everyone was aware of that. That on itself speeds up the reaction. But i think more importantly for a application like this is that the turbulent flow of gases mixes the fuel and oxidiser when confined, while it separates them while unconfined. The effect of which is bigger than one might expect. In a low explosive like black powder the effect of that is likely not to big because fuel and oxidiser are quite well mixed already and still we can observe a slow burn turning into a pretty snappy boom. But in a scenario like this where fuel and oxidiser would likely not be well mixed that effect could make drastic differences. I would reserve judgement about the actual danger at hand until tested in a confinement similar to a real application such as in a cold trap. To be clear i am **not** suggesting to make a experiment in confined conditions. With the passion for safety you guys show here that might not end well haha. I just want to say a conclusion such as "its not dangerous" from these tests alone is likely deceiving and could give a false sense of safety.
Thank you for the additinal insight. Using an actual cold trap to test that, would have certainly been better, but then we would also have to test, how easy it is to ignite accidentally, which would make this whole thing a lot more difficult. I did not conclude that any of this is safe. I only concluded that the reactions I observed were a lot less violent then what I would have expected.
Explosives need fragmentation to damage you or something that burns longer to light you up. If you have neither then it's mostly safe aside from the "soaking in liquid oxygen" scenario
Thanks Elias. Just think of a confined automatic mixer thus time. Even gasses explode with 4km/s blastwave, so plz keep your extremities (i was close to losing mine a few times).
With the LOX+propane mixture the initial flame is the propane burning by combining with the oxygen in the air above it and the second much more impressive boom is from the boundary with the LOX igniting
LOX doesn't burn, for it supports combustion. Many of these mixtures may not do as expected because the fuel-to-oxidizer ratio is too far off to support burning, deflagration, or explosion.
I’m glad you went through with the experiment to ensure people understand the *reality* vs the myth of the chemistry. Respecting the chemistry is always wise, but being reasonable about the magnitude of effects is also important. I’m glad you cleared the hype.
The flash point of propane at standard conditions is -104°C so it takes at least a bit of energy to get it to ignite. I think it's hard to get that going when the solution is so cold unless you use something like a sparkler to ignite, I assume this is what you do when it works. Also, once it ignites most of the liquid is blown away by the pressure before it has time to react in liquid phase, so you get the big fireball instead. The final pop is presumably a residual mixture of the gases. I speculate that a wide, shallow vessel like the trays you use in the beginning would have a better result. Shredded sponges could also be a useful medium to absorb both liquids, but this is even more speculative.
I think that this video demonstration actually serves a very useful purpose: it helps people visuallize a little better the processes involved, and would help us to feel a little more relaxed if we had to work around something like this. If there were ever some crazy emergency that came up, we could have a little better assessment of our risk, and thereby avoid panicking and making a bad decision. Like if you were on the third floor of a building and something happened with liquid oxygen, you wouldn't want to panick and go jump out of the window. Now anything that were to happen indoors is way more dangerous though, because the wind can't disperse the explosive mixtures. But this demonstration at least shows how much safer it is to be outdoors with any really flammable or potentially explosive mixtures.
@@EliasExperiments Imagine if there were some sort of emergency where someone spilled liquid oxygen outside while doing an experiment, but the person was also injured and needed help. Prior to watching this video we might be inclined to think that there would almost certainly be a dangerous explosion any second, so we might be inclined to grab the injured person and drag them as quickly as possible away from the spilled oxygen, which could end up doing additional injury to the person. By having a general idea of what the actual risk is, we can make a better decision and avoid unnecessary further injuries. This is obviously an extremely unlikely hypothetical scenario, but just in general people tend to panic when they are suddenly put into a situation with something that is perceived as extremely dangerous and not well understood, and panicking in of itself can sometimes be worse than the incident that gave rise to it.
What's probably going on is that in liquid form O2 won't easily react since you're removing a lot of heat. As soon as that oxygen comes back up to room temperature, and you've created an oxygen rich environment, almost anything will burn. You're really lucky nothing caught prematurely.
The reaction with the sponges tells us that the contact area and mixture of the LOx is probably what limits the other reactions. The sponges absorb the LOx into every pore. The wood dust and sugar probably pack together too tightly. The charcoal probably only absorbs LOx into the outer surface.
Haha! I have rarely laughed and cringed so much at the same time watching a video :D We should definitely repeat such a day! It was a lot of fun! Super cut and I also like the thumbnail very much!
No need to cringe, you added a lot of value to the video! I am sure that we will definetly repeat such a day. For the thumbnail I had some help, this is beyond my capabilities :P
I imagine whats causing the explosion with the propane and oxygen mix is largely similar mechanics to a fuel air bomb once the mix is right from the initial fireballs force
If we are looking for dangerous things to do with liquid oxygen, aerosolising it in cryogenic conditions with something like propane would be a wild ride. SpaceX has manage to produce some impressive explosions with the mixture in the past few years.
There is a difference between bravery and stupidity. I think this is the later. Look at the actors. It is clear they don't really know what will happen.
you're becoming my favorite channel, I LOVE THIS, I had this idea for so long and couldn't find out why nobody has tried it! also, I'm checking out thy labs and advanced tinkering as well :D seems like they have similar content! P.S. I made sodium using the downs process recently, not much, but enough to hold and see! which is particularly impressive because nobody else on youtube has done it on a small scale that I know of, they all just do the castner process.
@@EliasExperiments yeah, me too, I'm still busy helping my family through harvest season... farming is boring for me though, and I would love to make a chemistry TH-cam channel. its been a dream for a while now. thanks for the reply!
I just got recommended this channel from the algorithm, and I love it! Keep up the great work, I think your channel is gonna do really well! Thanks for mythbusting this, people really freak out about oxygen. Ive had so many try to tell me that oxygen is flammable.
Had always heard that liquid oxygen spill on asphalt was especially hazardous. Not only for the potential energy of the reaction, but that the two became unstable and could be detonated by impact. Have never seen anyone willing to try an oxy-asphalt mix on video, so there MIGHT be something to the level of hazard there.
Since you are obviously German, how long did it take before the first random person demanded to see your liquid oxygen license or at least threatened to call the police on you?
You know, if you used a stake, a string and a swivel you could pour stuff into the other container from a safe distance. It would save you a whole lot of running and probably be a lot less stressful.
That wood dust burn off was pretty cool! Nice lil bang there at the end. Enjoyed watching guys being guys, and no one lost a hand, so that’s always nice.
It´s great seeing a new "energetic video" from Elias. So it just takes liquid O2, liquid propane and a bunch of "daredevils" to create some Hollywood-like blasts. Many thanks for the exciting entertainment and please more of the good stuff!💥💥💥
I know German is closely related with English. But it's really surprising how they are so fluent and sound really good with English. On the other hand, we can't understand German by default.
I think it's more about poorly-ventilated confined rooms with textiles like carpets, chairs, clothes; which unknowingly absorb a large excess of oxygen, over time nitrogen and argon are displaced, then if a tiny spark drops on the floor you have a massive flash fire because everything is suddenly burning, including your lab coat, hair, etc.
Very interesting results in many of these combinations. Agree with the other commenters about the containment factor being a key component of the reactions. It is fascinating to know that technically you don't need separate tanks for a liquid propane / oxygen rocket as it will separate by its density on its own. You'd just have to know where to draw the different fuels out of that tank. The sugar/oxygen one seems very promising as a rocket motor fuel.
@@EliasExperimentsDidn't the Germans come up with a thermobaric bomb during WW2 using coal dust and liquid oxygen? There's not much information out there about it other than it's existence and that it was extremely powerful for the time. If you're ever in the mood to add containment into future experiments, I'd really like to see it with coal dust (+ burster and ignition charges😊).
I have no idea, I would have to research that for myself. The wikipedia articel oxyliquid at least states that LOX and charcoal powder has been used as an explosive in the past, but was too unreliable. The thing about adding containment is, that you quickly wander into illegal territory.
@@EliasExperiments An excellent point! I thought you were going to have a "mini bleve" with the lox/LNG but it didn't do what I thought it was going to do at all - proving why experimenting and actual science are still incredibly important; because sometimes real results just aren't what you think they are going to be.
I'd be curious to see what happens if you match the temps better. the propane and the LO2 have vastly different boiling points, so I wonder if giving them both a bath in LN2 to supercool them to identical temps if they would mix better I would imagine that if you are worried about atmospheric air condensing in lab equipment, anything that makes it to that point is going to be the same temp as the LO2, Also, I bet if you tried this in anything with a constricted opening, that energy level is going to go up up up. You got a decent bang and that container was blunderbuss shaped. *any* confinement and you're going to exponentially increase that speed So please use a plastic soda bottle next time 😉😉
As soon as the liquids are in the same container their temperatures will be equal quite quickly. So freezing everything with liquid nitrogen won't help mixing the liquids. It might help freezing everything solid and mixing it as a powder, but that sounds very dangerous with substances like that. Plastic soda bottle certainly sounds like a very fun idea :D
@@EliasExperiments I was more thinking that the lo2 is colder than the lp, but they are both fighting to equalize temps. My thought is that if both are super cooled past their boiling points to equal temps, they will play together better than the lo2 furiously boiling to try to keep the lp cold
During World War 2, experiments were carried out to see whether a small cargo vessel with both a liquid fuel and liquid oxygen could spill its cargo in a harbour and blow everything up. I seem to recall that the experiments were not sufficiently successful to be pursued.
Even if they were successful - there's got to be some very major benefits compared to conventional fuel-air explosives to warrant such a complicated endeavor. Why carry the oxidizer with you, in a dangerous cryogenic form no less, if it's everywhere around you anyway after all? Edit - Maybe that's how they came up with fuel-air explosives in the first place.
I used to work for a gas company. One time the valve that connects the trucks up to the giant tank of liquid oxygen via a tube caught on fire, the large metal valve! No idea how it started, but a large chunk of metal burnt away like it was burning plastic.
@@EliasExperiments haha! Good on you! This incident in that job actually caused so much fear in the truck driver who was filling his tank he had to take time off work and visit a therapist for PTSD. It's funny that you're trying to do it for fun (I'm on the same page as you really though, metal burning like plastic is brilliant).
I also understand the truck drivers perspective. If you really don't want something like this to happen it can be quite dramatic. Confronting something voluntarily always is something quite different psychologically :D
I wasn’t expecting to see a full on detonation from this experiment. I would love to see that recorded with a high speed camera at several thousand frames per second
The English used one ton aircraft bombs filled with a mixture of liquid oxygen and coal dust. They had a functional shelf life of four hours (they needed to be dropped within four hours to explode). Like gunpowder they need confinement to detonate. The major advantage is they were very very cheap to make.
The problem with the charcoal was that it was in lumps not powder. Lamp black is sold commercially as an explosive in sticks because there are no handling restrictions on it and when it's mixed with liquid oxygen it doesn't need a detonator and a primary explosive like ANFO just a simple igniter like they used here. Even so preparation of a large area with dozens of drilled boreholes for a mining operation is far more practical to setup with many boreholes connected by detcord over a period of days.
@EliasExperiments Lamp black is a rare more finely divided substance than ground charcoal because it's collected smoke. If you try it be aware that the equivalent of a stick of dynamite when fully soaked in liquid oxygen is around 50 grams.
So the basic question here is "is DDT occurring or not?" I really don't know if your propane-LOX mixture is reacting from the heat of nearby burning Propalox, or from compression by the explosion. If there is DDT it's probably only useful as an explosive. If there is no DDT then you could use it as a premixed propellant for a potato cannon or something.
I was first confused about DDT and thought of the insecticide. But I guess you mean deflagration to detonation transition. I am in no way qualified to answer your question.
When servicing USAF F-16 LOX bottles on the flightline we found LOX freezes water bugs (those get big in the Southern bases) mole crickets and frogs instantly which then shatter agreeably when tossed on the concrete ramp. LOX also does an amazing job chilling six packs (use a paper bag, NOT plastic which is petroleum). Do with that what you will.
My dad worked at an oil refinery and one day he accidently spilled propane odorant on himself. This stuff is really strong. You only need a pint of odorant to a rail care of propane. Mom burned the clothes he was wearing and he did everything he could to kill the smell, but it was still 2 or 3 weeks before the smell was gone. When he got home from work on the day, the smell was eye watering.
I believe they use ethyl mercaptan for that (it's used for natural gas). ALL mercaptans (thiols) are very odoriferous. My organic chemistry professor said that when he was an undergrad at UC Berkley, he made a small vial of butyl mercaptan, released it in San Francisco, and the police in Oakland, across the Bay, received calls about the stench.
An interesting thing about propane is it's melting point is below that of methane, ethane, ethylene (ethene), and propylene (propene) in spite of being a higher molecular weight, though propylene is the closest to it of those. Methane, ethane and ethylene all freeze above oxygen's boiling point (-183C), so you'd end up with hydrocarbon slush if mixed with LOX, but propane's MP is at -188C and propene's at -185.2C, so either of those would work. Also interestingly, the other two 3 carbon hydrocarbon molecules both have much higher melting points (propadiene and propyne AKA methyl acetylene) at -136 and -152.9 C, so trying to mix a MAPP gas blend with LOX would also end up with slush. (though that's not commonly available anymore, at least in the US due to manufacturing ceasing, and pure Propylene is used instead) Though as actual rocket fuel, this still leaves both propane and propene/propylene as interesting fuels given they can potentially be stored at the same temperature as LOX without freezing, even if the margin between the freezing point of fuel and boiling point of oxygen is still rather small, it's present, and would increase a bit if the oxygen stores could be held at even slightly above 1 atmosphere of pressure. Ethylene has a higher specific impulse than even methane, so a mixture containing that would be especially attractive. (though methane and propane would give the best economics) Though given the marginal difference is specific impulse even there, the greater density of propylene at LOX temperatures would be the greater advantage (higher density and better ISP than propane for comparison too, but propane has the cost advantage and even lower MP) Compared to hydrogen you have much lower specific impulse but also much higher bulk density and the ability to store close to the same temperature as LOX. Compared to kerosene rocket fuel (like RP-1), you have still significantly better specific impulse and also the ability to store at LOX temperatures. OTOH this also ignores the potential for eutectic mixtures to form with some of the above hydrocarbons (and possibly others not listed) as that could suppress the melting point well below that of the individual constituents. I can at least find an example for methane and ethane with eutectic point very close to a 50/50 mix (by mass, or 65/35 mix by mole fraction) with melting point suppressed to below 73K or -200C. (looks close to 72.5k) So that case would be quite useful for storage at LOX temperatures and relatively cost effective. I wonder if there are any useful eutectic mixtures formed with acetylene or even just good low temperature solubility in other hydrocarbon blends (without forming a true eutectic mixture) given acetylene specific impulse is very high, but melting point is only -80.8C, plus it becomes unstable under pressures much above 2 atm at room temperature (prone to spontaneous, explosive decomposition and polymerization when exposed to shock under those conditions), but is stable dissolved in acetone under pressure and should be considerably more stable at low temperatures, so solutions in cryogenic liquid hydrocarbons would seem ideal for this, though better still if they remain stable liquified under pressure at room temperature for easier storage and transportation. (OTOH acetylene could also be generated on-site using calcium carbide and blended into the desired composition with cryogenic liquid hydrocarbons on-site as well, and storing the blended mixture at capacities similar to those of on-site liquid hydrogen storage)
Have you considered the propane and oxygen mix could be made more reliable. instead of mixing the 2 together in a cup then igniting the layered mixture which doesn't always work, have a spraying stage using 2 nozzles set to deliver stoichiometric flow rates, to create a dense, uniform dispersal, with a well-timed ignitor/sparker to create quite an impressive fuel-air experience. You may need to be significantly further away when you do ignite it though, and for the love of god triple check your yield calculations.
3:31 to be fair, *any* pressure source can be made into a pipe bomb, by choosing the strength of the pipe correctly. And even without an actual exotherm, just boiling the O2 would release a lot of pressure. Add in the reaction between O2 and metal, the tendency of many metals to lose strength under even non-melting heat, the absence of gravity to separate the O2 from sugar, and the (at least) 17 kPa pressure difference (probably closer to either 21 or 100), and anyone trying to blow up that door, would blow it up pretty quick.
LOX isn't dangerous. Well mixed high volatility solvents and evaporating LOX are not a good combination. oxygen based detonation waves require pre mixing. Generally, this doesn't happen outside. Build a room hook up a gas line, bubble it through LOX. Wait a few hrs then turn on a compressor. You will successfully disassemble the room. You only achieved deflagration. The boom wasn't energetically driven it was a phase transition ...the heat from the burn just flash boiled the liquid oxygen. Sorry guys.
@@EliasExperiments you guys did a good job, and made a fun video! You didn't do anything too dangerous or risky. It's important to exercise caution when playing with this kind of thing. You definitely got some shock waves (1:1000 expansion ratio is no joke). Water is not "explosive," but it is just as dangerous as TNT when you start mixing it with steel and coal... there's some fascinating material science, chemistry and physics that can only be done using shock waves that should be explored and demonstrated to a general audience. The barrier to entry is of course safety and legal compliance. Good video!
Thank you! What do you mean water is as dangerous as TNT when mixed with steel and coal? The only time I have seen water go boom was when reacting water ice with 20 kg of thermite. Or when putting very hot half molten sodium chloride into it.
@@EliasExperiments read the books: Normal Accidents, or Atomic Accidents. The history of steam power is...messy... and that's AFTER the invention of the centrifugal governor! The expansion factor from liquid to gas is capable of driving significant shock waves. The brisance of the detonation wave may not be as high as with certain compounds but a driven shock front is still a driven shock front and only really depends on the mass & energy behind it. It doesn't matter how you produce the transformation from 1g/cc solid or 1/cc liquid to something that wants to exist at a density of 1mg/cc.
During ww2 when Germany was experiencing shortages of nitric acid they tried to use porous carbon with LOX as an explosive. Apparently it had the same performance as TNT(when initiated with blasting cap)but was far too sensitive
Great experiment. The missing element from this is that it was carried out at atmospheric pressure. A rule in mechanical workshops is to never oil the thread on compressed oxygen cylinder fittings. Someone must have done this at some time with bad results.
There are so many safety rules that are in place maybe because of one anecdotal not even officially confirmed incident. Or maybe just on the basis of theory, so it is always hard to tell what is actually dangerous and what not.
I have been wondering about this for a long time. If LO2 and propane were able to be mixed in the correct stoichiometric ratio, the energy density would be higher than any chemical explosive, including the weird ones like octanitrocubane. I would not have guessed that propane and LO2 were not miscible, since they should both be non-polar.
There are a lot of explosives that will burn if lit. The question is how many times you can burn it before getting a deflagration to detonation transition and you blow your face off. Also, a lot of these mixtures are known to detonate if dropped or impacted, and have low detonation initiation energy. Just because it doesn’t look like nitroglycerin doesn’t mean it won’t act like it…
I have tried LOx + charcoal before and it did work *A* *LOT* better. I did left the charcoal submerged into the LOx until the boiling stopped. They *exploded* well without confinement. Maybe different kind of charcoal? Maybe yours weren't fully absorbed with LOx?
They should have done it in an insulated container. It would be much more impressive. Also you need shitload of oxygen for carbon. I am glad they are not very good w explosives
I haven't finished the video yet, but perhaps try the sugar again, but after saturating it with liquid oxygen, stir it up for more surface area for the ignition to spread quicker? I'm not chemist or anything. Just a thought
Was ihr wirklich tun müsst ist: Nimmt flüssigen Propan/Ethan/Wasserstoff/oder was auch immer anderes Flüssiges Brennbares, schüttet es in eine (vorgekühlte) Thermosflasche, schüttet, in der richtigen molaren Menge, flüssigen Sauerstoff rein und verschließt es mit einer, mit Zündladung, modifizierten Thermoskappe. Das wird schallern! WICHTIG: Sorgt dafür, dass ihr die Flasche möglichst Ferngesteuert schließt, weil der entstehende Druck in der Thermosflasche *könnte* zu einer Selbstentzündung führen
I’m thinking you need to shock with an impact. C4 explosive if flammable like a lot of the mixtures yall used, but when struck with force would explode.
Very interesting series of experiments. The liquid propane/O2 reaction is especially so. Liquid propane is non-flammable until it reaches a gaseous state, then you can get significant energy if the fuel/air ratio is correct. The primary (blast) burners on hot air balloons use this principal; they are fueled by liquid propane but the propane transitions to vapor just after leaving the nozzles in the burner. The liquid is heated by those coils you see in the flame stream so it is ready to flash into vapor as soon as it exits those nozzles. The energy those burners produce is pretty amazing; one company used to claim over 30 MILLION BTU output for their burners (most claim about half that), but given the output of most home heating furnaces are 80-100K BTU output, even the more "modest" 15 Million BTU outputs of other burners is still a huge amount. Very likely what you were seeing was something similar to what is called a BLEVE (Boiling Liquid Expanding Vapor Explosion): Initial ignition of the vapor cloud above the container, followed by the liquid components heating to their vapor point/boiling, the vapors combining until optimum ratio was reached while burning at sub-optimal conditions and then detonating when a portion reached that optimum ratio. Any remaining liquids would be violently dispersed at that point, leading to even more violent combustion as more vaporized and combined at the right ratios. Of course, this all occurred very quickly after ignition. (NOTE: This is also a similar principal used in a fuel-air bomb like the MOAB) If you want to see a REALLY violent result, try putting some form of "expelling charge" (it needn't be flammable, a funnel & compressed air would work) in the bottom of your container of mixed liquid propane and O2 and igniting the cloud of expelled mist in the air above it - - but i would stand WAY BACK! (see Myth Busters and their experiments with igniting powdered creamer and other ingredients).
@@vrghr I think the fireball was from propane burning rich as it floats on LOX but the fact that it was literally in drink cups and leaving craters implies it did go high order likely as the liquid and solid mixture rather than expand out then explode. I might be wrong but the shock delivered to the ground seems to agree with what I'm thinking. If it was a volumetric explosion it would look a bit more like the one the hydraulic press channel did. More diffuse and less focused directly underneath the cup.
it should be noted that liquid oxygen fires/explosions perform far better under pressure, as the oxygen doesn't absorb as much heat as it reacts, leading to more heat which causes a faster reaction which causes more heat etc. as is, I believe that the oxygen is absorbing quite a bit of that possibly explosive energy as it boils during the reaction, leading to relatively lackluster results
Nitrous oxide mixes much better with nonpolar liquids like hydrocarbons (and doesn't mix well with LOX) Or semi-polar oganic compounds like ketones and ethers, and would be interesting to compare the hazards of with liquid oxygen. It's relatively soluble in acetone at room temperature and acetone's freezing point is well below nitrous oxide's boiling point, so those two should mix as well. The same for diethyl ether, which may be miscible with liquid nitrous oxide. It also dissolves into other organic compounds like fats and oils and/or dissolves them when in its liquid form, which might be the more dangerous thing for spills or leaks. OTOH handling supercooled acetone is probably more dangerous than LOX and liquid propane given it may stick to your skin and not simply boil off.
Charcoal soaked in LOX has been used for blasting. The charcoal is pulverized, a blasting cap is used, and the mixture is confined in a metal cylinder. The advantage of this explosive is that, if it fails to go off, you just have to wait for the O2 to evaporate, then it becomes safe. The disadvantage, of course, is the hassle in transporting the LOX to the site & making the charges.
I wouldn't necessarily trust Wikipedia. I've encountered errors there, a number of times. But consider.....An intense flame-front from a blasting cap, propagating through LOX saturated crushed charcoal. I don't see how there could NOT be an explosion. Maybe Wiki was saying that it was unreliable, if you waited too long to set it off, and the LOX evaporated.
I doubt if those mining engineers bothered to do the stoichiometry, measuring out LOX with graduated cylinders constructed like Dewar flasks! :) They just filled up the tubes to the max, which guaranteed an excess. So a little loss of O2 wouldn't be a big deal.
Guys I think you're finding out what being lucky vs unlucky is a lot more than actual safety information. The activation energy of that propane/oxygen mixture is so low and you're standing next to it in synthetic clothing? One stray bit of static and this video could have been really different. I'm all for having fun but lox is fickle. It's totally fine right up until one day it bites.
Of course you are right, that this video cannot be mistaken for proper safety training. Horrible accidents can certainly happen a lot faster then one can imagine. All I did was experiement how liquid oxygen behaves, when you mix it with certain substances and commenting on what I felt and observed. Yes it is certainly possible to do this more safely. I definetly will improve the safety aspect in the future.
To be fair to The Martian, in the book they say that the DIY bomb was made using also a closed container to increase it's power. I am also reasonably sure they allowed the oxygen to soak into it for a long white. Maybe if you try it again consider using powdered sugar instead of crystal for better mixing.
Was at a party once where a guy brought a potato gun that was feed with Propane, and O2. Ignited with a sparkplug and a battery. That produced QUITE a pop and blasted the potatoes!
A GA Pilot I know was flying some passengers cross country in a light plane. Because the plane was not pressurized they had all been on supplemental oxygen for several hours. The pilot told the passengers not to smoke until they had changed their clothes after the flight. When they stopped for fuel and to stretch their legs one of the passengers had gone behind a hanger to sneak a cigarette. The other passengers learned why they had been told not to smoke. It had nothing to do with the pilot not wanting to sit there smelling smoke smells. The screams told the pilot what had happened and even a fast response could not save the poor smoker.
Oh wow that sounds like a cruel story. I really wonder if oxygen get's adsorbed onto clothing that well. I have heard two or three similar stories in the comments and I find them hard to believe. Something I want to fact check! ;-) Thank you for the input!
@@EliasExperiments I'm not sure if "absorbed" is the correct word. There are plenty of sources you can find online that talk about the safety of oxygen. You don't have to take my word for it.
I am not talking about the safety of oxygen, I know it can be dangerous. What I am really interested in is this particular incident you described. If not "absorbed" what would you call it?
Mixtures of organic substances with liquid oxygen are full-fledged explosive mixtures that were previously used in the mining industry. Even a slight limitation of the space for the gases formed during combustion is enough, and an increase in pressure can lead to an increase in the combustion speed above the speed of sound, which is detonation. Although the brisance of such mixtures is low, it is easy to get contusions or injuries to the limbs and eyes.
Moit LOX based explosives can be compared to guncotton. To get detonation they must either be confined ( as mentioned by Muonium in the comment below ) or they must be ignited with a blasting cap/detonator. It would be very interesting if you made a new video where you tried to ignite some of the mixtures here, either confined in a metal casing or with a blasting cap.
Suspend a steel, glass ball or a rock directly above the liquids. Using a string as a trip wire, drop the object into the liquids as you ignite them. The splash will mix them. Glass, steel and rocks are theoretically projectiles..... But on the bright side, it can't hit all of you. 😁
You need to mix high pressure oxygen and hydrogen in a bottle next, it should make for some of the fastest low explosives possible. But beware of fragmentation...
Regardless of what language you speak or your country of origin, we all have the same "I am an adult doing something extremely unwise" laugh.
Lol, great point! XD
The missing puzzle piece appears largely to be one of the *confinement* of such reactions. The highly unconsolidated (albeit homogeneous) nature of the sawdust oxygen mixture allows the mass to disassemble itself in a weak deflagration analogous to a pile of black powder on a table being ignited. When confined in a rigid container however, (possibly only even in a glass cold trap) both mixtures absolutely will detonate violently.
Yeah with confimenment you can certainly make it more dangerous, but I was not to keen on experimenting with that and getting accused of bomb building. XD
Yep, even nitroglycerin or C4 will burn with an ordinary flame when ignited, it's all about the initiation energy and confinement.
@@flomojo2u Doesn't C4 require a blasting cap to actually detonate? That stuff is super stable.
it does, nitroglycerin will actually just puff into smoke but there are stories of people using c4 instead of a portable solid fuel for cooking MREs in the army, its one of the few things the mythbusters did that really really shocked me, cant find the mythbusters episode but there are some vids on yt @@Boomchacle
@@BoomchacleYes c4 (rdx) is a secondary explosive and requires a blasting cap to be set off.
The actual danger of liquid oxygen is saturating stuff you don't want to burn, like clothes on your body, with it without noticing and then being turned into a human blow torch so quickly you can't react to it before being covered in 3rd degree burns because of static discharge.
Static discharge is actually really bad at lighting this, but if you get very unlucky anything can be really dangerous. I guess driving a car is generally a lot more dangerous.
@@EliasExperiments The thing is, oxygen saturated clothing means that if another thing goes wrong, it goes really, really, REALLY wrong, as in, the life you had before the accident is over.
In other words, if there is a 1 in 100000 chance you turn into a human flare, will that number comfort you when you're in a burn ward after the freakest accident actually happens?
Comparing it to car accidents doesn't really fit if you consider the billions of dollars worth or R&D spent to make cars and roads safer because humans are easily distracted monkeys with ego problems.
Also, a dismissive attitude about safety - even jokingly - has claimed many lives of those who thought it couldn't happen to them. Wood burning microwave transformers come to mind - total widowmakers.
So I am perfectly aware that what I did in this video could have gone horrible wrong.
The thing is anything you do in live can go very horribly wrong.
You can't have no risk in life. If you don't do anything to avoid making mistakes you will probably regret it at the end of your life and that would be a horrible tragedy in itself.
Why can I not compare it to car accidents? Should I compare it to extreme sports, or overeating, or what would you prefer?
No matter what you do tragedy and horror lurks everywhere. If you have a solution to safely avoid tragedy I would love to hear it.
I am by no means dismissive about safety. I am dismissive about a wrong perception of reality and not putting actions into proper perspective. Like this video vs. car driving, extreme sports, overeating etc.
There are always two extremes: Being safe and being completly irresponsible are two nice opposites. However being on the safety extreme it no good either in my opinion. I think it is far better to learn how to deal with dangerous stuff instead of trying to hide from it. That would be the lesson of sleeping beauty ;-)
So how about you pick your poison, I will chose mine? ;-)
@@EliasExperiments It’s just good to be aware of what the dangers are.
Your clothes were in a plume of concentrated oxygen vapor when trying to cool that propane. Maybe it would be better to just use nitrogen when trying to cool something.
That pan of wood dust had potential to blow violently if there was a slightly different amount of oxygen, or different mixing or type/point of ignition.
The propane thing managed to blow up just from a flame in an open container. Most things that do that are things you don’t want to stir or shake by hand.
@@EliasExperiments I guess the point is, there’s little moments of danger that aren’t as obvious as what you would see when driving. I probably missed a lot more than I noticed. Just because something like this worked 11 times doesn’t mean it will work safely the 12th.
Laughing Germans blowing things up is never a good sign.
You better watch out! XD
@@EliasExperimentsJetzt hab ich Angst...
This is funny. I'm sorry, Germans.
it is the best sign there is
@@ryanrenolds Solltest du...
Im a pyrotechnician from germany and i think i have a valuable comment:
in my experience things that combust in a harmless manner when unconfined can make a surprising boom when confined.
When the hot gases cant escape temperature and pressure build, im sure everyone was aware of that. That on itself speeds up the reaction. But i think more importantly for a application like this is that the turbulent flow of gases mixes the fuel and oxidiser when confined, while it separates them while unconfined. The effect of which is bigger than one might expect. In a low explosive like black powder the effect of that is likely not to big because fuel and oxidiser are quite well mixed already and still we can observe a slow burn turning into a pretty snappy boom. But in a scenario like this where fuel and oxidiser would likely not be well mixed that effect could make drastic differences.
I would reserve judgement about the actual danger at hand until tested in a confinement similar to a real application such as in a cold trap.
To be clear i am **not** suggesting to make a experiment in confined conditions. With the passion for safety you guys show here that might not end well haha. I just want to say a conclusion such as "its not dangerous" from these tests alone is likely deceiving and could give a false sense of safety.
Thank you for the additinal insight.
Using an actual cold trap to test that, would have certainly been better, but then we would also have to test, how easy it is to ignite accidentally, which would make this whole thing a lot more difficult.
I did not conclude that any of this is safe. I only concluded that the reactions I observed were a lot less violent then what I would have expected.
"This is so blatantly irresponsible that it cannot be put into words"
😂
Haha exactly :D
POV: German scientist in 1943 experimentating the right mixture to find an efficient propeller for V2 rockets (colourized).
Haha lol, great comment! XD
Next video: pouring liquid hydrogen on solid oxygen
Liquid hydrogen will be coming up, so subscribe that you don't miss it! ;-)
Good blend of fun and terrifying! Amazed how tame most of them were.
Yes I was truly amazed too! Thank you for the feedback!
Explosives need fragmentation to damage you or something that burns longer to light you up. If you have neither then it's mostly safe aside from the "soaking in liquid oxygen" scenario
Now I want to see 2/3 liquid Hydrogen with 1/3 liquid oxygen
I will try to do it this winter!
Thanks Elias. Just think of a confined automatic mixer thus time. Even gasses explode with 4km/s blastwave, so plz keep your extremities (i was close to losing mine a few times).
@@dannydetonator Well they can't really confine anything without violating explosives laws.
With the LOX+propane mixture the initial flame is the propane burning by combining with the oxygen in the air above it and the second much more impressive boom is from the boundary with the LOX igniting
That could certainly be the case. This has to be investigated more closely haha.
LOX doesn't burn, for it supports combustion. Many of these mixtures may not do as expected because the fuel-to-oxidizer ratio is too far off to support burning, deflagration, or explosion.
@@EliasExperiments Needs to be filmed with both a thermal camera and a high speed camera
I’m glad you went through with the experiment to ensure people understand the *reality* vs the myth of the chemistry. Respecting the chemistry is always wise, but being reasonable about the magnitude of effects is also important. I’m glad you cleared the hype.
Thank you for the kind feedback!
It's probably not gonna be bad, but if it gets bad, it's gonna be REAL BAD....which is probably where the excessive caution comes in.
Yeah that's a good point.
I assume you've seen the old post of George Gobel dumping 10L of LOX onto 50 lb of charcoal and a lit cigarette? Good video.
Yes I have seen that :D
I used to freeze all kinds of things in leftover LOX we used to service aircraft in the military. Energy drinks make great instant Popsicles!
Oh wow that sounds really dangerous
that was a very nice blast, gas mixtures always give a nice sound.
Yeah certainly :D
@@EliasExperimentstry frozen acetylene and then powder that, acetylene has very worrying properties but isnt sensitive to hammer when frozen solid
The flash point of propane at standard conditions is -104°C so it takes at least a bit of energy to get it to ignite. I think it's hard to get that going when the solution is so cold unless you use something like a sparkler to ignite, I assume this is what you do when it works. Also, once it ignites most of the liquid is blown away by the pressure before it has time to react in liquid phase, so you get the big fireball instead. The final pop is presumably a residual mixture of the gases. I speculate that a wide, shallow vessel like the trays you use in the beginning would have a better result. Shredded sponges could also be a useful medium to absorb both liquids, but this is even more speculative.
Yeah that certainly could have work. So much to try for future experiments!
2:24 when you ask your chemist friend to light the barbecue... :D
He burns down the entire grill as well XD
I think that this video demonstration actually serves a very useful purpose: it helps people visuallize a little better the processes involved, and would help us to feel a little more relaxed if we had to work around something like this. If there were ever some crazy emergency that came up, we could have a little better assessment of our risk, and thereby avoid panicking and making a bad decision. Like if you were on the third floor of a building and something happened with liquid oxygen, you wouldn't want to panick and go jump out of the window. Now anything that were to happen indoors is way more dangerous though, because the wind can't disperse the explosive mixtures. But this demonstration at least shows how much safer it is to be outdoors with any really flammable or potentially explosive mixtures.
Thank you for the kind feedback! I am glad that I am doing something useful in your opinion :-)
@@EliasExperiments Imagine if there were some sort of emergency where someone spilled liquid oxygen outside while doing an experiment, but the person was also injured and needed help. Prior to watching this video we might be inclined to think that there would almost certainly be a dangerous explosion any second, so we might be inclined to grab the injured person and drag them as quickly as possible away from the spilled oxygen, which could end up doing additional injury to the person. By having a general idea of what the actual risk is, we can make a better decision and avoid unnecessary further injuries. This is obviously an extremely unlikely hypothetical scenario, but just in general people tend to panic when they are suddenly put into a situation with something that is perceived as extremely dangerous and not well understood, and panicking in of itself can sometimes be worse than the incident that gave rise to it.
Yeah that is definetly a great point. Thank you for mentioning that!
Oh man, don't go blaming me if something like this goes terribly wrong!
Wow I did not expect to see you here
Don't worry I will take responsibilty for my own actions ;-)
What's probably going on is that in liquid form O2 won't easily react since you're removing a lot of heat. As soon as that oxygen comes back up to room temperature, and you've created an oxygen rich environment, almost anything will burn. You're really lucky nothing caught prematurely.
That is certainly a very good point, that I didn't manage to articulate yet. Thank you for the input!
Was trained to service air craft with LOX.. was always told if you put oil in the LOX it would blow up.. or a tar ball.
There is certainly the risk, but definetly no guarantee :D
Risk is much higher if it is a used oil with metal particles. They will accelerate oxidation.
The reaction with the sponges tells us that the contact area and mixture of the LOx is probably what limits the other reactions. The sponges absorb the LOx into every pore. The wood dust and sugar probably pack together too tightly. The charcoal probably only absorbs LOx into the outer surface.
That is certainly a possible explanation. Further testing is required! :D
Haha! I have rarely laughed and cringed so much at the same time watching a video :D
We should definitely repeat such a day! It was a lot of fun!
Super cut and I also like the thumbnail very much!
No need to cringe, you added a lot of value to the video!
I am sure that we will definetly repeat such a day.
For the thumbnail I had some help, this is beyond my capabilities :P
I imagine whats causing the explosion with the propane and oxygen mix is largely similar mechanics to a fuel air bomb once the mix is right from the initial fireballs force
Yeah that might be. Sounds like an interesting hypothesis!
If we are looking for dangerous things to do with liquid oxygen, aerosolising it in cryogenic conditions with something like propane would be a wild ride.
SpaceX has manage to produce some impressive explosions with the mixture in the past few years.
Haha lol, but that is not exactly what we are going for XD
Impressive!
I'm not talking only about the spectacular reactions, but the bravery of the experimenters. :-)
Lol, thank you so much!
There is a difference between bravery and stupidity. I think this is the later. Look at the actors. It is clear they don't really know what will happen.
Is it possible that some of those mixtures were too oxygen rich?
Certainly ;-)
you're becoming my favorite channel, I LOVE THIS, I had this idea for so long and couldn't find out why nobody has tried it! also, I'm checking out thy labs and advanced tinkering as well :D seems like they have similar content!
P.S. I made sodium using the downs process recently, not much, but enough to hold and see! which is particularly impressive because nobody else on youtube has done it on a small scale that I know of, they all just do the castner process.
Thank you for the kind feedback!
I would definetly love to see your downs cell process in video format!
@@EliasExperiments yeah, me too, I'm still busy helping my family through harvest season... farming is boring for me though, and I would love to make a chemistry TH-cam channel. its been a dream for a while now. thanks for the reply!
Don't let your dreams be dreams! Haha
I just got recommended this channel from the algorithm, and I love it! Keep up the great work, I think your channel is gonna do really well! Thanks for mythbusting this, people really freak out about oxygen. Ive had so many try to tell me that oxygen is flammable.
Thank you for the kind words, I will try my best to continue!
Enjoyed this way more than I should, especially your banter!
Haha, thank you so much!
Had always heard that liquid oxygen spill on asphalt was especially hazardous. Not only for the potential energy of the reaction, but that the two became unstable and could be detonated by impact.
Have never seen anyone willing to try an oxy-asphalt mix on video, so there MIGHT be something to the level of hazard there.
I am certainly willing to try it. It is noted on my ideas for future video list!
Since you are obviously German, how long did it take before the first random person demanded to see your liquid oxygen license or at least threatened to call the police on you?
Lol I did this as an official event so it was all fine ;-)
@@EliasExperiments Ah, okay 😀
You know, if you used a stake, a string and a swivel you could pour stuff into the other container from a safe distance. It would save you a whole lot of running and probably be a lot less stressful.
Yes that is indeed a great idea! We did that in the past and we should really go back to it.
You guys had some hilarious comments. I would quote them here but there were too many. Loved it.
Haha, thank you for the kind feedback!
That wood dust burn off was pretty cool! Nice lil bang there at the end. Enjoyed watching guys being guys, and no one lost a hand, so that’s always nice.
Haha, thank you!
It´s great seeing a new "energetic video" from Elias. So it just takes liquid O2, liquid propane and a bunch of "daredevils" to create some Hollywood-like blasts. Many thanks for the exciting entertainment and please more of the good stuff!💥💥💥
Thank you for the kind feedback, I will try my best to do so!
"Welcome back to my laboratory where safety is number one priority!"
In this case it would be like third priority :D
Crazy Russian Hacker to be remembered 😂
So jealous knowing you guys are fluent in German and English. I can count in German, that's all....
I am sure you can learn it just like we did ;-)
I know German is closely related with English.
But it's really surprising how they are so fluent and sound really good with English.
On the other hand, we can't understand German by default.
I think it's more about poorly-ventilated confined rooms with textiles like carpets, chairs, clothes; which unknowingly absorb a large excess of oxygen, over time nitrogen and argon are displaced, then if a tiny spark drops on the floor you have a massive flash fire because everything is suddenly burning, including your lab coat, hair, etc.
Yes that would indeed be a big problem :D
Very interesting results in many of these combinations. Agree with the other commenters about the containment factor being a key component of the reactions. It is fascinating to know that technically you don't need separate tanks for a liquid propane / oxygen rocket as it will separate by its density on its own. You'd just have to know where to draw the different fuels out of that tank. The sugar/oxygen one seems very promising as a rocket motor fuel.
I wouldn't want to build a rocket with oxygen and propane in the same tank. That is crying for a disaster to happen lol.
@@EliasExperimentsDidn't the Germans come up with a thermobaric bomb during WW2 using coal dust and liquid oxygen? There's not much information out there about it other than it's existence and that it was extremely powerful for the time. If you're ever in the mood to add containment into future experiments, I'd really like to see it with coal dust (+ burster and ignition charges😊).
I have no idea, I would have to research that for myself. The wikipedia articel oxyliquid at least states that LOX and charcoal powder has been used as an explosive in the past, but was too unreliable. The thing about adding containment is, that you quickly wander into illegal territory.
@@EliasExperiments An excellent point! I thought you were going to have a "mini bleve" with the lox/LNG but it didn't do what I thought it was going to do at all - proving why experimenting and actual science are still incredibly important; because sometimes real results just aren't what you think they are going to be.
Yes exactly theory and practice are often two entirely different things.
I saw the title and I immediately thought “what kind of crazy person mixes liquid propane and smoked salmon?”
Lol now I get the salmon reference from other comments. Thank you for clearing that up! For me as a chemist LOX is only liquid oxygen haha :D
I'd be curious to see what happens if you match the temps better. the propane and the LO2 have vastly different boiling points, so I wonder if giving them both a bath in LN2 to supercool them to identical temps if they would mix better
I would imagine that if you are worried about atmospheric air condensing in lab equipment, anything that makes it to that point is going to be the same temp as the LO2,
Also, I bet if you tried this in anything with a constricted opening, that energy level is going to go up up up. You got a decent bang and that container was blunderbuss shaped. *any* confinement and you're going to exponentially increase that speed
So please use a plastic soda bottle next time 😉😉
As soon as the liquids are in the same container their temperatures will be equal quite quickly. So freezing everything with liquid nitrogen won't help mixing the liquids. It might help freezing everything solid and mixing it as a powder, but that sounds very dangerous with substances like that.
Plastic soda bottle certainly sounds like a very fun idea :D
@@EliasExperiments I was more thinking that the lo2 is colder than the lp, but they are both fighting to equalize temps. My thought is that if both are super cooled past their boiling points to equal temps, they will play together better than the lo2 furiously boiling to try to keep the lp cold
Maybe, but it is quite dangerous to play with stuff like that for any longer then we did.
During World War 2, experiments were carried out to see whether a small cargo vessel with both a liquid fuel and liquid oxygen could spill its cargo in a harbour and blow everything up. I seem to recall that the experiments were not sufficiently successful to be pursued.
Even if they were successful - there's got to be some very major benefits compared to conventional fuel-air explosives to warrant such a complicated endeavor.
Why carry the oxidizer with you, in a dangerous cryogenic form no less, if it's everywhere around you anyway after all?
Edit - Maybe that's how they came up with fuel-air explosives in the first place.
Wow that is very interesting, thank you for sharing that!
Geile Nummer😅 was mir am besten gefallen hat, war die mit der Länge des Video's "zunehmende" Professionalität😂
Haha, danke Dir!
I used to work for a gas company. One time the valve that connects the trucks up to the giant tank of liquid oxygen via a tube caught on fire, the large metal valve! No idea how it started, but a large chunk of metal burnt away like it was burning plastic.
Wow that sounds spectacular. I was trying to reproduce a similar effect, but I didn't have much sucess yet.
@@EliasExperiments haha! Good on you! This incident in that job actually caused so much fear in the truck driver who was filling his tank he had to take time off work and visit a therapist for PTSD. It's funny that you're trying to do it for fun (I'm on the same page as you really though, metal burning like plastic is brilliant).
I also understand the truck drivers perspective. If you really don't want something like this to happen it can be quite dramatic. Confronting something voluntarily always is something quite different psychologically :D
Fun times. I can still feel the sweat when pouring the oxygen in that bottle xD
Ah so that is your YT Channel! :P
@@EliasExperiments It is indeed :D
I wasn’t expecting to see a full on detonation from this experiment. I would love to see that recorded with a high speed camera at several thousand frames per second
That is certainly a great idea. Now I only need to get a high speed camera :D
Schönes Video wieder!
Thank you!
The English used one ton aircraft bombs filled with a mixture of liquid oxygen and coal dust.
They had a functional shelf life of four hours (they needed to be dropped within four hours to explode).
Like gunpowder they need confinement to detonate.
The major advantage is they were very very cheap to make.
That sounds very dangerous I don't think I wanna try it :D
The problem with the charcoal was that it was in lumps not powder. Lamp black is sold commercially as an explosive in sticks because there are no handling restrictions on it and when it's mixed with liquid oxygen it doesn't need a detonator and a primary explosive like ANFO just a simple igniter like they used here. Even so preparation of a large area with dozens of drilled boreholes for a mining operation is far more practical to setup with many boreholes connected by detcord over a period of days.
I am not sure if powdered charcoal would react so much more easily. Something to test for future experiments!
@EliasExperiments
Lamp black is a rare more finely divided substance than ground charcoal because it's collected smoke. If you try it be aware that the equivalent of a stick of dynamite when fully soaked in liquid oxygen is around 50 grams.
So the basic question here is "is DDT occurring or not?" I really don't know if your propane-LOX mixture is reacting from the heat of nearby burning Propalox, or from compression by the explosion. If there is DDT it's probably only useful as an explosive. If there is no DDT then you could use it as a premixed propellant for a potato cannon or something.
I was first confused about DDT and thought of the insecticide. But I guess you mean deflagration to detonation transition. I am in no way qualified to answer your question.
When servicing USAF F-16 LOX bottles on the flightline we found LOX freezes water bugs (those get big in the Southern bases) mole crickets and frogs instantly which then shatter agreeably when tossed on the concrete ramp. LOX also does an amazing job chilling six packs (use a paper bag, NOT plastic which is petroleum). Do with that what you will.
Oh wow it's impressive you had LOX to play with. I have rarely seen anyone who was not terrified to death of LOX.
My dad worked at an oil refinery and one day he accidently spilled propane odorant on himself.
This stuff is really strong. You only need a pint of odorant to a rail care of propane.
Mom burned the clothes he was wearing and he did everything he could to kill the smell, but it was still 2 or 3 weeks before the smell was gone.
When he got home from work on the day, the smell was eye watering.
Yeah we also had accidents with similar stuff at the institute I work at. It is more dangerous then one might think :D
I believe they use ethyl mercaptan for that (it's used for natural gas). ALL mercaptans (thiols) are very odoriferous. My organic chemistry professor said that when he was an undergrad at UC Berkley, he made a small vial of butyl mercaptan, released it in San Francisco, and the police in Oakland, across the Bay, received calls about the stench.
Yes that is quite dangerous :D
Black gunpowder if unconfined will just burn. But if you confine it, it will explode nicely.
Yes that is true, but the goal was not necessarily to create a big explosion, we just wanted to explore the reactivity of liquid oxygen.
An interesting thing about propane is it's melting point is below that of methane, ethane, ethylene (ethene), and propylene (propene) in spite of being a higher molecular weight, though propylene is the closest to it of those. Methane, ethane and ethylene all freeze above oxygen's boiling point (-183C), so you'd end up with hydrocarbon slush if mixed with LOX, but propane's MP is at -188C and propene's at -185.2C, so either of those would work.
Also interestingly, the other two 3 carbon hydrocarbon molecules both have much higher melting points (propadiene and propyne AKA methyl acetylene) at -136 and -152.9 C, so trying to mix a MAPP gas blend with LOX would also end up with slush. (though that's not commonly available anymore, at least in the US due to manufacturing ceasing, and pure Propylene is used instead)
Though as actual rocket fuel, this still leaves both propane and propene/propylene as interesting fuels given they can potentially be stored at the same temperature as LOX without freezing, even if the margin between the freezing point of fuel and boiling point of oxygen is still rather small, it's present, and would increase a bit if the oxygen stores could be held at even slightly above 1 atmosphere of pressure.
Ethylene has a higher specific impulse than even methane, so a mixture containing that would be especially attractive. (though methane and propane would give the best economics)
Though given the marginal difference is specific impulse even there, the greater density of propylene at LOX temperatures would be the greater advantage (higher density and better ISP than propane for comparison too, but propane has the cost advantage and even lower MP)
Compared to hydrogen you have much lower specific impulse but also much higher bulk density and the ability to store close to the same temperature as LOX. Compared to kerosene rocket fuel (like RP-1), you have still significantly better specific impulse and also the ability to store at LOX temperatures.
OTOH this also ignores the potential for eutectic mixtures to form with some of the above hydrocarbons (and possibly others not listed) as that could suppress the melting point well below that of the individual constituents. I can at least find an example for methane and ethane with eutectic point very close to a 50/50 mix (by mass, or 65/35 mix by mole fraction) with melting point suppressed to below 73K or -200C. (looks close to 72.5k) So that case would be quite useful for storage at LOX temperatures and relatively cost effective.
I wonder if there are any useful eutectic mixtures formed with acetylene or even just good low temperature solubility in other hydrocarbon blends (without forming a true eutectic mixture) given acetylene specific impulse is very high, but melting point is only -80.8C, plus it becomes unstable under pressures much above 2 atm at room temperature (prone to spontaneous, explosive decomposition and polymerization when exposed to shock under those conditions), but is stable dissolved in acetone under pressure and should be considerably more stable at low temperatures, so solutions in cryogenic liquid hydrocarbons would seem ideal for this, though better still if they remain stable liquified under pressure at room temperature for easier storage and transportation. (OTOH acetylene could also be generated on-site using calcium carbide and blended into the desired composition with cryogenic liquid hydrocarbons on-site as well, and storing the blended mixture at capacities similar to those of on-site liquid hydrogen storage)
Wow those are some very interesting insights thank you for sharing that! ;-)
Have you considered the propane and oxygen mix could be made more reliable. instead of mixing the 2 together in a cup then igniting the layered mixture which doesn't always work, have a spraying stage using 2 nozzles set to deliver stoichiometric flow rates, to create a dense, uniform dispersal, with a well-timed ignitor/sparker to create quite an impressive fuel-air experience. You may need to be significantly further away when you do ignite it though, and for the love of god triple check your yield calculations.
Yeah that certainly sounds like a safe and simple way to do it XD
Or in other words the injection head of a rocket engine, just not in a combustion chamber
3:31 to be fair, *any* pressure source can be made into a pipe bomb, by choosing the strength of the pipe correctly.
And even without an actual exotherm, just boiling the O2 would release a lot of pressure. Add in the reaction between O2 and metal, the tendency of many metals to lose strength under even non-melting heat, the absence of gravity to separate the O2 from sugar, and the (at least) 17 kPa pressure difference (probably closer to either 21 or 100), and anyone trying to blow up that door, would blow it up pretty quick.
Yeah I didn't think about it that deeply, but it is certainly a great point!
LOX isn't dangerous. Well mixed high volatility solvents and evaporating LOX are not a good combination. oxygen based detonation waves require pre mixing. Generally, this doesn't happen outside. Build a room hook up a gas line, bubble it through LOX. Wait a few hrs then turn on a compressor. You will successfully disassemble the room.
You only achieved deflagration. The boom wasn't energetically driven it was a phase transition ...the heat from the burn just flash boiled the liquid oxygen. Sorry guys.
Could be, but the goal wasn't to disassemble a room, it was just to learn more about liquid oxygen ;P
@@EliasExperiments you guys did a good job, and made a fun video! You didn't do anything too dangerous or risky. It's important to exercise caution when playing with this kind of thing. You definitely got some shock waves (1:1000 expansion ratio is no joke). Water is not "explosive," but it is just as dangerous as TNT when you start mixing it with steel and coal... there's some fascinating material science, chemistry and physics that can only be done using shock waves that should be explored and demonstrated to a general audience. The barrier to entry is of course safety and legal compliance. Good video!
Thank you! What do you mean water is as dangerous as TNT when mixed with steel and coal? The only time I have seen water go boom was when reacting water ice with 20 kg of thermite. Or when putting very hot half molten sodium chloride into it.
@@EliasExperiments read the books: Normal Accidents, or Atomic Accidents. The history of steam power is...messy... and that's AFTER the invention of the centrifugal governor! The expansion factor from liquid to gas is capable of driving significant shock waves. The brisance of the detonation wave may not be as high as with certain compounds but a driven shock front is still a driven shock front and only really depends on the mass & energy behind it. It doesn't matter how you produce the transformation from 1g/cc solid or 1/cc liquid to something that wants to exist at a density of 1mg/cc.
Thank you for the book recommendations! Sounds interesting!
During ww2 when Germany was experiencing shortages of nitric acid they tried to use porous carbon with LOX as an explosive. Apparently it had the same performance as TNT(when initiated with blasting cap)but was far too sensitive
What I have read was, that it was far too unreliable.
Aah I probably misunderstood the report... I guess at lox temperatures primary explosives would be too cold to detonate
Really nice video!
Thank you so much!
You are my favorite TH-cam chemistry channel.
I am glad you like it! ;-)
You should try freezing gasoline with liquid oxygen and then igniting it.
That would certainly be an interesting idea for an upcoming video!
That was a great idea having Advanced tinkering and Thy labs help. Why blow off your fingers when you can have them do it for you.
Exactly!
Great experiment. The missing element from this is that it was carried out at atmospheric pressure. A rule in mechanical workshops is to never oil the thread on compressed oxygen cylinder fittings. Someone must have done this at some time with bad results.
There are so many safety rules that are in place maybe because of one anecdotal not even officially confirmed incident. Or maybe just on the basis of theory, so it is always hard to tell what is actually dangerous and what not.
So did the oxygen-propane mixture undergo detonation? It seemed like after the initial flame there was no flame when it exploded?
I don't know if you can call it that. I have heared differnt opinions about that here in the comments. I would have to research that for myself.
I have been wondering about this for a long time. If LO2 and propane were able to be mixed in the correct stoichiometric ratio, the energy density would be higher than any chemical explosive, including the weird ones like octanitrocubane. I would not have guessed that propane and LO2 were not miscible, since they should both be non-polar.
Why would you guess they are not misicible when both are non-polar? As far as I know liquids with similar polarities can mix quite well.
@@EliasExperiments I think I worded that poorly. My guess was that they should be miscible, for the reasons you outlined.
There are a lot of explosives that will burn if lit.
The question is how many times you can burn it before getting a deflagration to detonation transition and you blow your face off.
Also, a lot of these mixtures are known to detonate if dropped or impacted, and have low detonation initiation energy. Just because it doesn’t look like nitroglycerin doesn’t mean it won’t act like it…
That's a fair point. Certainly an interesting aspect to investigate for future experiments ;-)
@@EliasExperiments … from a distance 👍🏻
I have tried LOx + charcoal before and it did work *A* *LOT* better. I did left the charcoal submerged into the LOx until the boiling stopped. They *exploded* well without confinement.
Maybe different kind of charcoal? Maybe yours weren't fully absorbed with LOx?
All of that could be true, or we added to much liquid oxygen, which cooled the reaction.
They should have done it in an insulated container. It would be much more impressive. Also you need shitload of oxygen for carbon. I am glad they are not very good w explosives
I haven't finished the video yet, but perhaps try the sugar again, but after saturating it with liquid oxygen, stir it up for more surface area for the ignition to spread quicker? I'm not chemist or anything. Just a thought
That might help, but from what I have seen with the sawdust, I don't think it will be much more spectacular.
Was ihr wirklich tun müsst ist: Nimmt flüssigen Propan/Ethan/Wasserstoff/oder was auch immer anderes Flüssiges Brennbares, schüttet es in eine (vorgekühlte) Thermosflasche, schüttet, in der richtigen molaren Menge, flüssigen Sauerstoff rein und verschließt es mit einer, mit Zündladung, modifizierten Thermoskappe. Das wird schallern!
WICHTIG: Sorgt dafür, dass ihr die Flasche möglichst Ferngesteuert schließt, weil der entstehende Druck in der Thermosflasche *könnte* zu einer Selbstentzündung führen
Das klingt nach einer wirklich extrem gefährlichen Angelegenheit haha.
@@EliasExperiments Das ist ja der Sinn der Sache
Everything not to do while experimenting.
Pretty much, yes :D
The dangerous part is indeed the change from liquid state to gas, when it suddenly needs a lot of space, don't try this in a sealed container ...
That would certainly make it a lot more dangerous.
I’m thinking you need to shock with an impact. C4 explosive if flammable like a lot of the mixtures yall used, but when struck with force would explode.
That is if the goal it to create a detonation, which was not the primary objective.
Very interesting series of experiments. The liquid propane/O2 reaction is especially so. Liquid propane is non-flammable until it reaches a gaseous state, then you can get significant energy if the fuel/air ratio is correct. The primary (blast) burners on hot air balloons use this principal; they are fueled by liquid propane but the propane transitions to vapor just after leaving the nozzles in the burner. The liquid is heated by those coils you see in the flame stream so it is ready to flash into vapor as soon as it exits those nozzles. The energy those burners produce is pretty amazing; one company used to claim over 30 MILLION BTU output for their burners (most claim about half that), but given the output of most home heating furnaces are 80-100K BTU output, even the more "modest" 15 Million BTU outputs of other burners is still a huge amount.
Very likely what you were seeing was something similar to what is called a BLEVE (Boiling Liquid Expanding Vapor Explosion): Initial ignition of the vapor cloud above the container, followed by the liquid components heating to their vapor point/boiling, the vapors combining until optimum ratio was reached while burning at sub-optimal conditions and then detonating when a portion reached that optimum ratio. Any remaining liquids would be violently dispersed at that point, leading to even more violent combustion as more vaporized and combined at the right ratios. Of course, this all occurred very quickly after ignition. (NOTE: This is also a similar principal used in a fuel-air bomb like the MOAB)
If you want to see a REALLY violent result, try putting some form of "expelling charge" (it needn't be flammable, a funnel & compressed air would work) in the bottom of your container of mixed liquid propane and O2 and igniting the cloud of expelled mist in the air above it - - but i would stand WAY BACK! (see Myth Busters and their experiments with igniting powdered creamer and other ingredients).
Wow that is all very interesting! Thank you for the additional info!
@@EliasExperiments You're very welcome!
@@vrghr I think the fireball was from propane burning rich as it floats on LOX but the fact that it was literally in drink cups and leaving craters implies it did go high order likely as the liquid and solid mixture rather than expand out then explode. I might be wrong but the shock delivered to the ground seems to agree with what I'm thinking. If it was a volumetric explosion it would look a bit more like the one the hydraulic press channel did. More diffuse and less focused directly underneath the cup.
it should be noted that liquid oxygen fires/explosions perform far better under pressure, as the oxygen doesn't absorb as much heat as it reacts, leading to more heat which causes a faster reaction which causes more heat etc.
as is, I believe that the oxygen is absorbing quite a bit of that possibly explosive energy as it boils during the reaction, leading to relatively lackluster results
That could certainly be a contributing factor. Explosives generally perform better under pressure haha.
I think a more stoichiometric mixture is needed. It seems like way too little oxygen give the amount of fuel you are throwing at these reactions.
Could be, more experiments are needed ;-)
when someone says something is a terrible idea i need to try it
Well good luck and have fun :D
Nitrous oxide mixes much better with nonpolar liquids like hydrocarbons (and doesn't mix well with LOX) Or semi-polar oganic compounds like ketones and ethers, and would be interesting to compare the hazards of with liquid oxygen. It's relatively soluble in acetone at room temperature and acetone's freezing point is well below nitrous oxide's boiling point, so those two should mix as well. The same for diethyl ether, which may be miscible with liquid nitrous oxide.
It also dissolves into other organic compounds like fats and oils and/or dissolves them when in its liquid form, which might be the more dangerous thing for spills or leaks.
OTOH handling supercooled acetone is probably more dangerous than LOX and liquid propane given it may stick to your skin and not simply boil off.
That sounds like a great idea to see if liquid nitrous oxide can mix with liquid propane :D
This really is the meaning of "me and the boys:"
Haha, right!
It's funny that it bangs twice, first with the gaseous oxygen in the air and only then with the liquid oxygen below for the big badda-boom!
Yeah that's very interesting.
Charcoal soaked in LOX has been used for blasting. The charcoal is pulverized, a blasting cap is used, and the mixture is confined in a metal cylinder. The advantage of this explosive is that, if it fails to go off, you just have to wait for the O2 to evaporate, then it becomes safe. The disadvantage, of course, is the hassle in transporting the LOX to the site & making the charges.
Yeah and explosives like that are quite unreliable according to wikipedia :D
I wouldn't necessarily trust Wikipedia. I've encountered errors there, a number of times. But consider.....An intense flame-front from a blasting cap, propagating through LOX saturated crushed charcoal. I don't see how there could NOT be an explosion. Maybe Wiki was saying that it was unreliable, if you waited too long to set it off, and the LOX evaporated.
My guess is that it is unrealiable, because it is really hard to always have the same amount of oxygen due to evaporation.
I doubt if those mining engineers bothered to do the stoichiometry, measuring out LOX with graduated cylinders constructed like Dewar flasks! :) They just filled up the tubes to the max, which guaranteed an excess. So a little loss of O2 wouldn't be a big deal.
Yes, but too much LOX would also cause a weaker explosion, because a lot of the energy will get lost just to evaporate the LOX.
0:14 I actually didn't know liquid oxygen was used in space rockets! Very cool 😮
Thank you for the kind feedback!
@@EliasExperiments no problem!
@@EliasExperimentsare you fine with video recommendations? I have something want to see but it might be a tad bit dangerous 😅
Guys I think you're finding out what being lucky vs unlucky is a lot more than actual safety information. The activation energy of that propane/oxygen mixture is so low and you're standing next to it in synthetic clothing? One stray bit of static and this video could have been really different.
I'm all for having fun but lox is fickle. It's totally fine right up until one day it bites.
Of course you are right, that this video cannot be mistaken for proper safety training. Horrible accidents can certainly happen a lot faster then one can imagine.
All I did was experiement how liquid oxygen behaves, when you mix it with certain substances and commenting on what I felt and observed. Yes it is certainly possible to do this more safely. I definetly will improve the safety aspect in the future.
FYI, no cured salmon was wasted in this video. My TH-cam algorithm was just confused.
Lol yes that is correct :D
"A modern recreation of the German rocket program."
Lol certainly :D
This all comes down to surface area exposed to outside atmospheric pressures it seems
Definetly!
To be fair to The Martian, in the book they say that the DIY bomb was made using also a closed container to increase it's power. I am also reasonably sure they allowed the oxygen to soak into it for a long white. Maybe if you try it again consider using powdered sugar instead of crystal for better mixing.
I am not saying it can't be done as described in The Martin, but it also isn't super easy.
Was at a party once where a guy brought a potato gun that was feed with Propane, and O2. Ignited with a sparkplug and a battery. That produced QUITE a pop and blasted the potatoes!
Oh wo that sounds fun :D
A GA Pilot I know was flying some passengers cross country in a light plane.
Because the plane was not pressurized they had all been on supplemental oxygen for several hours.
The pilot told the passengers not to smoke until they had changed their clothes after the flight.
When they stopped for fuel and to stretch their legs one of the passengers had gone behind a hanger to sneak a cigarette.
The other passengers learned why they had been told not to smoke. It had nothing to do with the pilot not wanting to sit there smelling smoke smells.
The screams told the pilot what had happened and even a fast response could not save the poor smoker.
Oh wow that sounds like a cruel story. I really wonder if oxygen get's adsorbed onto clothing that well. I have heard two or three similar stories in the comments and I find them hard to believe. Something I want to fact check! ;-)
Thank you for the input!
@@EliasExperiments I'm not sure if "absorbed" is the correct word.
There are plenty of sources you can find online that talk about the safety of oxygen. You don't have to take my word for it.
I am not talking about the safety of oxygen, I know it can be dangerous. What I am really interested in is this particular incident you described. If not "absorbed" what would you call it?
Mixtures of organic substances with liquid oxygen are full-fledged explosive mixtures that were previously used in the mining industry. Even a slight limitation of the space for the gases formed during combustion is enough, and an increase in pressure can lead to an increase in the combustion speed above the speed of sound, which is detonation. Although the brisance of such mixtures is low, it is easy to get contusions or injuries to the limbs and eyes.
Hm that's interesting.
Super fun and exciting video. Wondered since I was a kid what lighting liquid gas rocket fuel would look like. Wasnt dissapointed.
Thank you for the kind feedback!
How much difference would there been using liquid O3. We had tanks of liquid O3 in a factory I worked in. Needed it for the cutting torches
It would make a huge difference and a couple of things would probably already ignite on contact.
5:02 Advanced Sinkering
Haha, nice!
How do you obtain these gasses in liquid form?
By cooling them with a cryocooler.
Moit LOX based explosives can be compared to guncotton. To get detonation they must either be confined ( as mentioned by Muonium in the comment below ) or they must be ignited with a blasting cap/detonator. It would be very interesting if you made a new video where you tried to ignite some of the mixtures here, either confined in a metal casing or with a blasting cap.
Yeah that would certainly be interesting, but also very difficult territory legally :D
Welcome to my laboratory where safety is number one priority. 👍
Maybe like number three haha :D
Flüssigsauerstoff und LPG vielleicht mit etwas Emulvin damits sich besser mischt?
Ja das wird mit Sicherheit funktionieren bei diesen Temperaturen :D
Suspend a steel, glass ball or a rock directly above the liquids. Using a string as a trip wire, drop the object into the liquids as you ignite them. The splash will mix them.
Glass, steel and rocks are theoretically projectiles..... But on the bright side, it can't hit all of you. 😁
That is a very interesting idea. Magnetic stirring was another suggestion, or a blender XD
@@EliasExperiments blenders make sparks, so use a looooooong extension cord 😁
You need to mix high pressure oxygen and hydrogen in a bottle next, it should make for some of the fastest low explosives possible. But beware of fragmentation...
I will try to make liquid hydrogen next haha