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Zeolite retains heat indefinitely, absorbs 4x more heat than water

extremetech.com

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Re: Zeolite retains heat indefinitely, absorbs 4x more heat than water

#31
post #28

How selective is the zeolite in what it absorbs? Could this be used for water purification? That is, if you let the zeolite absorb water from an impure source, move it to a clean container and heat it to release the water, is the water potable? Even if it selectively absorbs water to remove contaminants, does the zeolite itself make the water non-potable?

Actually, yes: water softeners use zeolites to remove various minerals from the water. See this for an explanation:

http://www.watervalue.com/watersofteners.html

Re: Zeolite retains heat indefinitely, absorbs 4x more heat than water

#32
post #8

Earlier quoted context omitted.

I'd like to see some energy density numbers in units I can understand before I would jump up and down about this use. (I'm not saying you're wrong so much as saying I can't provide evidence you're right, and I'm hoping someone else can. Or at least tell us what exactly "the heat storage capability of water" is such that something can have 4 times as much. Please hold wild-assed guesses, please, I can compute the ener…

The term of art you're looking for is "specific heat". https://en.wikipedia.org/wiki/Specific_heat The relevant number for water at 25C is 4.184 joules per gram. But this isn't a strict apples to apples comparison: if you heat and cool zeolite in a vacuum chamber, it'll have a pathetic specific heat. (Like perlite, another foamed mineral, which has a specific heat of something like 0.1) That's because there's a chemi…

The specific heat is the energy needed to raise the temperature per mass. So for water it takes 4.184 joules per gram to raise the temperature by 1 kelvin. So if you heated water to 75 degrees you would have put in about 205 joules per gram. You then have to deal with conductive losses and the efficiency of a heat engine.

This is not directly comparable to the energy density of gasoline or a lithium ion battery which use chemical reactions to store the energy. So you can turn almost 100% of the energy in a lithium ion battery into useful work but if you put the equivalent number of joules into heating an object you wouldn't get close unless you have a handy 0 kelvin object.

Re: Zeolite retains heat indefinitely, absorbs 4x more heat than water

#33

>By applying heat to Fraunhofer’s zeolite comes into contact with water, a chemical reaction adsorbs the water and emits heat. Parse Error: Unexpected verb "comes" on line 129.

Thank goodness I am not the only one for whom that sentence makes no sense!

Re: Zeolite retains heat indefinitely, absorbs 4x more heat than water

#34

>By applying heat to Fraunhofer’s zeolite comes into contact with water, a chemical reaction adsorbs the water and emits heat. Parse Error: Unexpected verb "comes" on line 129.

Try By applying heat to Fraunhofer’s zeolite as it comes into contact with water, a chemical reaction adsorbs the water and emits heat.

Re: Zeolite retains heat indefinitely, absorbs 4x more heat than water

#36

>By applying heat to Fraunhofer’s zeolite comes into contact with water, a chemical reaction adsorbs the water and emits heat. Parse Error: Unexpected verb "comes" on line 129.

Also: "adsorbs."

EDIT: upon further research, I find that "adsorption" is actually also a thing, but it appears that here they meant the traditional absorption. Adsorbtion definitely isn't a thing. Also it sounds like a baby trying to say "abortion," which is weird.

What possesses people to give things such similar names? And while we're at it, mathematicians: stop using variables that rhyme. Bs, Cs, Ds, Es, Ps, Zs, it makes my head hurt. Would it kill you to chuck an H or a Q in there? M and N, now thats just purely vindictive. How am I supposed to cope with that?

After writing this comment I think the spelling part of my brain is now fried forever. And to think I've been walking around merrily saying "absorbsion" all these years...

Re: Zeolite retains heat indefinitely, absorbs 4x more heat than water

#38

Earlier quoted context omitted.

Can you give me some examples of how this can be used?

You can heat Zeolite using solar power during the day and release the energy at night. Current thermal energy storage techniques use stuff like molten salt ( http://en.wikipedia.org/wiki/Thermal_energy_storage ), which is a lot harder to work with than pellets.

Yeah, but once you do that, how do you get the water back out? It sounds like this stuff doesn't do that very easily.

Re: Zeolite retains heat indefinitely, absorbs 4x more heat than water

#39

>By applying heat to Fraunhofer’s zeolite comes into contact with water, a chemical reaction adsorbs the water and emits heat. Parse Error: Unexpected verb "comes" on line 129.

Also: "adsorbs." EDIT: upon further research, I find that "adsorption" is actually also a thing, but it appears that here they meant the traditional absorption. Adsorbtion definitely isn't a thing. Also it sounds like a baby trying to say "abortion," which is weird. What possesses people to give things such similar names? And while we're at it, mathematicians: stop using variables that rhyme. Bs, Cs, Ds, Es, Ps, Zs,…

> but it appears that here they meant the traditional absorption

Sorry to add extra "fry" you your brain, but it appears they really did mean "adsorbtion" -> http://en.wikipedia.org/wiki/Zeolite

Which makes a lot of the science understandable. I can't help thinking that by saying "OMG hard science, so here is a massively dumbed down version" they actually made crucial parts of the theory incomprehensible :)

Case in point being; adsorbtion explains later comments about why surface area is important.

Re: Zeolite retains heat indefinitely, absorbs 4x more heat than water

#40

>By applying heat to Fraunhofer’s zeolite comes into contact with water, a chemical reaction adsorbs the water and emits heat. Parse Error: Unexpected verb "comes" on line 129.

Also: "adsorbs." EDIT: upon further research, I find that "adsorption" is actually also a thing, but it appears that here they meant the traditional absorption. Adsorbtion definitely isn't a thing. Also it sounds like a baby trying to say "abortion," which is weird. What possesses people to give things such similar names? And while we're at it, mathematicians: stop using variables that rhyme. Bs, Cs, Ds, Es, Ps, Zs,…

>And while we're at it, mathematicians: stop using variables that rhyme. Bs, Cs, Ds, Es, Ps, Zs, it makes my head hurt.

I had a linear algebra teacher who was (I think) from Ukraine. Roughly all letters rhymed when he said them, and "a", "e", "i" were homophones.

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