need conductive fluid, NO WATER!

[Shelnutt2]

For my MHD generator I need a conductive fluid, but it can't be water based, as electrolysis takes place with the water and I end up loosing all my eltricity to splitting the (salt) water, when I don't want to. So I need something that isn't water based thats highly conductive, cheap, and easy to get.

I'd love to use gallium but its way to expensive. The fluid has to be a fluid at room temp.

[Maviryk]

vinegar? some sort of acid?

[shard]

Mercury?

[Shelnutt2]

Mercury?

Where can I get mercury cheaply? I haven't found a supplier of mercury..

I guess I'll have to go with an acid of some sorts.

[Roofles]

Uhm.. Acids in liquid form are all water based.... thats how they become acidic.

You need a conductive oil or something then.

[Shelnutt2]

You need a conductive oil or something then.


Any in mind?
What about a grease? I mean Artic Silver 5 is conductive. No way I'm using AS5 way too expensive and thick, but grease in general..hmm..

[seadave77]

How much of this fluid are you looking for?

[Shelnutt2]

How much of this fluid are you looking for?

right now I need about 250 ml. I used 250 ml of water

[||Console||]

vodka =)

haha I was on google and look what I found http://www.physicsforums.com/showthread.php?t=174515

http://www.rfmicrolink.com/liquid_Conductive_rubber.html
http://www.ingentaconnect.com/content/tandf/tlct/2002/00000029/00000008/art00018
http://www.flowresearch.com/Worldflow_Handbook/chapter_one.htm

[Shelnutt2]

vodka =)

haha I was on google and look what I found http://www.physicsforums.com/showthread.php?t=174515

http://www.rfmicrolink.com/liquid_Conductive_rubber.html
http://www.ingentaconnect.com/content/tandf/tlct/2002/00000029/00000008/art00018
http://www.flowresearch.com/Worldflow_Handbook/chapter_one.htm

Lol, you found my other post:p

Alcohol is a good solution, I might end up giving it a try, rubbing alcohol is not too expensive.
The other thing I was thinking of was cooking grease. Is it conductive? I haven't been able to find any information on the conductivity of yellow grease.

That rubber is pretty cool, but it turns solid after you mix it..

[Quailane]

What can you add to alcohol or oil to make it conductive?

[Shelnutt2]

What can you add to alcohol or oil to make it conductive?

Salt? I'm not a chemist, I don't know..

[||Console||]

What if you didnt add the hardening agent to the Rubber ?

[SolidxSnake]

What can you add to alcohol or oil to make it conductive?


Alcohol is already conductive isn't it?

[Quailane]

Alcohol is already conductive isn't it?

Oh yeah, duh.

[Malpine Walis]

Well, alcohol is slightly conductive but not enough to use in this application. And I can say that with some authority because I googled "conductivity of alcohol" and the first link that came up was for a data table that is probably exactly what you are looking for.

There are 228 different materials listed in the conductivity table below. Green numbers indicate high conductivity fluids suitable for magnetic flowmeters. Orange numbers indicate low conductivity and may not lead to successful applications. Red numbers warn that conductivities are too low to use magnetic flowmeters.

http://www.smartmeasurement.com/en/wizards/flowmeter/flmtr_mag_conductivity.asp

Select the table, copy/paste into a spreadsheet and sort on column F and you have your data.

[shard]

Hmm, seems mercury is the WTFPWN of conductivity ;)

[David]

Acid in an organic solvent. Winnar.

HCl for something that dissociates to ions nicely and can be obtained relatively easily and cheaply.

As for the solvent - Methanol or IPA I'd reckon, the latter being less volatile than the former. Still protic solvents but not as polar as water.

EDIT: Methanol can be hygroscopic, acetonitrile might be a better bet.

[David]

Uhm.. Acids in liquid form are all water based.... thats how they become acidic.

You need a conductive oil or something then.

bzzzzt.

I frequently use acids in methanol and acetonitrile for carrying out reactions where water would interfere. Acetonitrile isn't even a protic solvent let alone close to water.


What can you add to alcohol or oil to make it conductive?

Maybe I'm wrong but I reckon anything that dissociates to form mobile ions. Hence my example above.

[Shelnutt2]

Acid in an organic solvent. Winnar.

HCl for something that dissociates to ions nicely and can be obtained relatively easily and cheaply.

As for the solvent - Methanol or IPA I'd reckon, the latter being less volatile than the former. Still protic solvents but not as polar as water.

EDIT: Methanol can be hygroscopic, acetonitrile might be a better bet.


Well I went out and bought myself some bottles of 91% Isopropyl alcohol, and a 2 liter thing of Ammonium (don't know the concentration). Acording to the site that Malpine linked me, it would seem that Ammonia would be a better solvent than IPA as it has a higher conductivity. Although ammonia is a lot more dangerous to handle. Now my question is what would you add? I'm quite afraid to start mixing things. I've never taken a Chemistry class in my life..

I suppose I need to find someone that has mixed chemicals before and get them to guide me through making a solution? I'm just afraid to do something wrong and blow my front yard/house/myself up...

[David]

Well I went out and bought myself some bottles of 91% Isopropyl alcohol, and a 2 liter thing of Ammonium (don't know the concentration). Acording to the site that Malpine linked me, it would seem that Ammonia would be a better solvent than IPA as it has a higher conductivity. Although ammonia is a lot more dangerous to handle. Now my question is what would you add? I'm quite afraid to start mixing things. I've never taken a Chemistry class in my life..

I suppose I need to find someone that has mixed chemicals before and get them to guide me through making a solution? I'm just afraid to do something wrong and blow my front yard/house/myself up...

I'd reckon the ammonia is likely a solution in water. So that's right out.

The IPA you could add hydrochloric acid to. Only issue with HCl is you're going to get hydrogen and chlorine forming should you apply a current and any sort of salt you add (a lot of which are horribly insoluble in organic solvents) will deposit stuff on your electrodes.

My original suggestion is likely a bad idea really - I guess you're better with just a conductive solvent without adding crap to it.

[Shelnutt2]

Yeah, if any solution dissolves in eletrical current that thats no good. I could make pure ammonia by passing an eletrical current to it to get ride of the water..but no sure if that would work.

I don't midn adding a few things together to get a more conductive solution, it just has to be able to withstand heat (~100C or more) and be conductive...

What about magnesium in the IPA? OR salt plus magnesium. Graphite might work too..

[David]

Yeah, if any solution dissolves in eletrical current that thats no good. I could make pure ammonia by passing an eletrical current to it to get ride of the water..but no sure if that would work.

I don't midn adding a few things together to get a more conductive solution, it just has to be able to withstand heat (~100C or more) and be conductive...

What about magnesium in the IPA? OR salt plus magnesium. Graphite might work too..

Inorganic materials are often poorly soluble in organic solvents. I doubt IPA would dissolve magnesium, or a lot of inorganic salts (although some like potassium carbonate like to deprotonate alcohols).

I'm not really sure to be honest.

[g14novak]

What about some sort of Alcohol (ex. Vodka? or Isopropyl) and some sort of metal flake or dust in it?

[Shelnutt2]

What about this.

hydrogen chloride + Ammonia = Ammonia chloride

Ammonium chloride + IPA (Isopropyl alcohol)?

Ammonium chloride is dissolvable in alcohol and water. So If that works then I'd have a conductive solution. Not as conductive as I want but its better than just straight ammonia or IPA...


also,
How expensive is mercury these days?

[Malpine Walis]

Um, hydrogen chloride is a gas at room temperature. so it would be amazingly hard to handle, not to mention quite dangerous. I believe that where it comes into contact with water, it becomes hydrochloric acid (like in your lungs id you get even a whiff of the stuff).

[Shelnutt2]

revelation!

I need something that has a low heat capacity.

So guys, whats a conductive solution that has low heat capacity? The lower the better.

I feel so dumb for not realising this before, thats one of my biggest issues.

Water might work again, I'm not sure, I need to run more test.

[David]

revelation!

I need something that has a low heat capacity.

So guys, whats a conductive solution that has low heat capacity? The lower the better.

I feel so dumb for not realising this before, thats one of my biggest issues.

Water might work again, I'm not sure, I need to run more test.

Water has quite a high heat capacity. 4.18kJ/mol/K if I recall correctly.