I keep a bottle of water in my trunk (everyone should) but this time of year it freezes solid. If I ever needed that bottle of water I would have to thaw it out for an extended period of time before drinking. People backpacking or hunting in very cold places might have the same problem when packing water. Most solutions to this problem involve some way to thaw the water, but that takes time and energy.
Enter the un-freezable emergency water bottle. A plastic bottle with a large carbon filter on top, followed by a particulate filter. The bottle is filled with a 50/50 mix of H2O and C2H6O2, so it won't freeze. Squeeze the bottle to force the mixture through the filter and into your mouth. Don't worry, that sweet taste is normal.-- DIYMatt, Nov 11 2014 You could always add a bit of salt...-- RayfordSteele, Nov 11 2014 wikipedia "Ethylene glycol is moderately toxic, with children having been particularly at risk because of its sweet taste, until it became common to add bitter flavoring to consumer antifreezes containing it."
So just add water to a half empty bottle of antifreze ?-- popbottle, Nov 11 2014 I don't think a carbon filter will remove anti-freeze from water. Also, drinking sub-zero temperature liquid is probably bad for you.-- xaviergisz, Nov 11 2014 // C2H6O2 //
That's also the formula for methoxymethanol, a most interesting compound ...
// Ethylene glycol is moderately toxic, with children having been particularly at risk because of its sweet taste, until it became common to add bitter flavoring to consumer antifreezes containing it. //
Fortunately, it's still possible to get the pure stuff. And, handily, it's also extremely toxic to cats.-- 8th of 7, Nov 11 2014 Piezo-electric bottle-top, with little heater and a rechargeable battery, well insulated bottle, and a few fish-scented regurgitant tablets labelled "eat me". As the water heads towards freezing it expands, so pressing on the bottle-top, which makes leccy, which heats the water up.
Due to entropy, battery assist would be useful. Battery could also be recharged by sliding magnet/coil wossername, so getting recharged in just day to day driving.
Hand me that patent form...-- not_morrison_rm, Nov 11 2014 If you would just filter the water extremely well, going into the bottle, it would have no nucleation points around which to freeze. It would freeze as you pour it out, but so would your idea.
I agree with [xaviergisz]. Drinking cold water is bad for you, drinking super-cold water would be worse. (I don't mean sipping a cold drink on a hot day, I mean trying to rehydrate with icewater at any time. (The only thing worse is trying to eat snow to keep alive.)) If you *need* the water, you need it to not be cold.-- baconbrain, Nov 11 2014 A thermos is already a pretty good way of keeping water from freezing, especially if you start with boiling water.
For long term water storage (i.e. in the trunk of your car) a thermos could be fitted with a switchable thermal conductivity element. When the ambient temperature is above a threshold (e.g. 20ºC) the element becomes thermally conductive, and below the threshold is thermally non-conductive. The element could be as simple as a bi-metallic strip that selectively forms a thermal bridge between the inside and outside of the thermos.-- xaviergisz, Nov 12 2014 Just add an amount of ethanol adjusted for your expected climate. Somewhere around 60 proof is adequate to prevent freezing around Boston.
Of course if you bump it up a bit further, you have the advantage of being able to light it on fire for warmth.-- MechE, Nov 12 2014 //I keep a bottle of water in my trunk (everyone should)//
Well, okay. But I'll need your car keys and address first.-- AusCan531, Nov 12 2014 Munge it into your engine compartment, alongside the exhaust manifold cooking set.-- FlyingToaster, Nov 12 2014 How about a week solution of hydrogen peroxide. Suck it through a silver catalyst straw and the H2O2 will break down and add to the water plus heat it up. Probably wouldn't actually work since you'd need a very weak solution to avoid an effect similar to trying to drink from a rocket engine. I couldn't find the freezing point of weak solutions, but a 50% solution freezes at -51C.-- scad mientist, Nov 12 2014 Best solution (unavoidable pun) to the problem so far, scad mientist. From the diagram on wikipedia on Hydrogen peroxide it appears the melting point of hydrogen peroxide in water is roughly equal to the percent in solution, so 10% H2O2 has melting point of -10ºC, 40% has a melting point of -40ºC.
Rather than a straw, it should be a high surface area element that is plunged into the hydrogen peroxide water solution. The element is left in until the hydrogen peroxide is substantially decomposed and the water heated.-- xaviergisz, Nov 12 2014 Ah, I see. You nearly got it. Simply replace ethylene glycol with C2H5OH. A 50:50 solution of this with water would not freeze until things got rather insanely cold. As a bonus, I've heard that C2H5OH Is readily metabolized and routinely used by cold Russians.-- bs0u0155, Nov 12 2014 //A 50:50 solution of this with water would not freeze until things got rather insanely cold.// Google told me about -40C, which is pretty chilly but not //insanely cold//.-- DIYMatt, Nov 12 2014 why not just keep the bottle of water in the cab where it is presumable not freezing?-- evilpenguin, Nov 12 2014 A simple sleeve containing sodium acetate, a la a skiing handwarmer, would do the trick. But I suppose the land that gave birth to Eddie the Eagle probably doesn't know much about skiing accessories...-- RayfordSteele, Nov 12 2014 //Eddie the Eagle probably doesn't know much about skiing accessories...//
Given that nowhere in England is more than 70 miles from the sea, and nowhere more than 70 yards from a reasonably well appointed coffee shop, dying of cold and dehydration is more of a leisure pursuit for us. Robert Falcon Scott was simply a correspondent for the "Summer Getaway"s column in The Times.-- bs0u0155, Nov 12 2014 // Rather than a straw, it should be a high surface area element that is plunged into the hydrogen peroxide water solution //
Yeah, I think that would work better. For example, I suspect that a 10% solution would have too much energy, and if that freezes at -10C, it couldn't be sucked through a straw anyway. If the catalyst is put in contact with the frozen solution, assuming a reaction can get started, the heat should melt more, making more H2O2 available for reacting until it is all melted.
It still might be tricky to get a concentration that releases enough energy to deal with the phase change if it is frozen but not get the water too hot if it starts out at room temperature. I guess one solution would be to carry a half-full bottle of water and a half full bottle of H2O2 solution. If both are liquid, just use the water, or if you want it a little warmer, add a little H2O2 solution to the water and stir. If the water is frozen, pour in a bunch of H2O2 and stir. If they are both frozen, use the catalyst to melt the H2O2 solution. The concentration should be chosen so that when the H2O2 is just barely frozen, the final temperature will be less than scalding. The nearly scalding water can be transferred to the bottle with ice long enough to cool it to the desired temperature. If it starts out far below freezing temperature, the final temperature may still be somewhat cold. There could be a burn hazard if the user puts the catalyst in the H2O2 solution when it is liquid without diluting it first, but there can be a warning label, and hopefully the concentration would be low enough that it wouldn't vaporize and cause an explosion hazard.
Also, for the catalyst, it might be convenient to just use some very fine silver powder. Apparently it's not very toxic and should be fine for occasional emergency use. Maybe even have it as a suspension in water (colloidal silver is available as an alternative medicine) to help get the reaction going faster when it is frozen. We might need to make that suspension with a high salt concentration so it never freezes, but if a small drop of this is added to a quart of water, the final salt concentration should not be disagreeable for drinking.-- scad mientist, Nov 12 2014 //-40C, which is pretty chilly but not //insanely cold////
Odin's hairy crotch, man. To someone who lives at sea level within 1000km of the equator, -40C certainly suits the definition "insanely cold" to me.
Maybehaps the problem is people trying to abide within unrealistically inhospitable climates? Like complaining that your martinis keep evaporating while hollidaying on the surface of the sun?-- Custardguts, Nov 12 2014 I've calculated that complete decomposition of a 4% hydrogen peroxide water solution will heat the water 50ºC, 8% to heat 100ºC (someone should check the maths),
If you needed something to operate below -8ºC (the melting point of 8% concentration) you could have nested chambers of higher concentration H2O2 to do a 'cascading' defrost.
Of course we are overthinking this - There are plenty of exothermic reactions that could be initiated in a separate chamber adjacent or within the water bottle to defrost the water. Trying to make the product of the exothermic reaction drinkable water is overkill.-- xaviergisz, Nov 12 2014 //the problem is people trying to abide within unrealistically inhospitable climates?//
Yup. That's it.-- bs0u0155, Nov 12 2014 Water. In a bottle. Under the front seat. Problem solved.-- WcW, Nov 13 2014 bottles: LOx, LH2 - now you can make drinking water instantly, even in Edmonton.-- FlyingToaster, Nov 13 2014 Dammit, I was just going to say hydrogen and oxygen...-- not_morrison_rm, Nov 13 2014 // bottles: LOx, LH2 // LOx? Sure some people think it's overkill to be prepared for -50C weather, but you're not really prepared unless you're ready for a sudden loss of oxygen in the atmosphere.
Ignoring the obvious containment issues, carrying LH2 is very efficient because it is much lighter than the water that can be produced. My H2O2 idea is actually quite inefficient since all that extra oxygen is heavy and doesn't add to the final volume of water.
Now you just need to figure out what to do with the excess heat when you make water.-- scad mientist, Nov 13 2014 //Ignoring the obvious containment issues,//
Marked for tagline-- bs0u0155, Nov 13 2014 from original idea: //People backpacking or hunting in very cold places might have the same problem when packing water. //
I've encountered this while taking my usual Camelbak water thingy up mountains in winter, the tube freezes very fast. Eventually the whole thing freezes. Fortunately I was never up mountains very long, but we solved the problem by taking vacuum flasks. Perhaps a vacuum flask would be a good enough insulator that to actually remove the heat energy to both reduce the temperature and then freeze the water would take so long that it doesn't happen, at least between periods of heating, e.g. the car heater being on and used.-- bs0u0155, Nov 13 2014 random, halfbakery