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Salting out is a process that can be used to dehydrate Isopropyl alcohol, i.e., separate it from water in an azeotropic solution. Dehydrated Isopropyl is useful as a fuel by itself and in helping to determine the right amount of catalyst to add when making bio-diesel fuel.

Removing water also increases the Isopropyl alcohol's ability to:

> melt ice off your frozen windshield
> dissolve water in gasoline
> burn cleaner when used as a standalone fuel
> provide your pet with an invigorating rub after his next bath, which is curiously strong enough (dry enough) to dislodge stubborn ticks and fleas
> serve as a powerful pet or human wound antiseptic
> wash out those wax filled ears
> save you big $$$ (dough, ka-ching, moola, etc.) think money*

(*99.9% Isopropyl Iso-Heet at auto stores runs around 18.25 cents per ounce. 99.9% Isopropyl made from salting out 50%-91% generic retail brand Isopropyl runs around 6.73 cents per ounce. That is a savings of over 63%. If you use it to dry your gasoline then be sure to remove the residual salt using the addendum method.)

What you need:

- bottle of 50% to 70% Isopropyl alcohol
- a wide mouth glass jar and lid, or other leak and Isopropyl proof container
- a pound of non-iodized table salt
- a turkey baster with a reduced size nozzle
- an empty bottle equal in size to the bottle of Isopropyl alcohol.
 
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Step 1: Start by adding the table salt

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Fill the empty jar about 1/4 full with table salt

Step 2: Add the hydrated Isopropyl alcohol

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Fill the jar about 3/4 full with hydrated (50% to 70%) Isopropyl alcohol

Step 3: Shake contents vigorously

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Put the lid on the jar, close to seal the contents and shake jar vigorously to be sure the salt and water combine.

Step 4: Let gravity separate the contents

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Place jar on a level surface long enough for the alcohol and salt water to separate (15 to 30 minutes).

Step 5: Keep the two layers separate

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Open jar carefully so as not to remix the two layers.

Step 6: Extract the Isopropyl alcohol

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Use the turkey baster to extract the top layer, which will be the Isopropyl alcohol.

Step 7: Fill the receiving bottle

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Fill a receiving bottle with the turkey baster Isopropyl contents.

Step 8: Label bottle

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Label the bottle "Dehydrated Isopropyl Alcohol"

Step 9: Use your dehydrated alcohol

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Use in an alcohol stove, lamp, torch, etc. or to give your pet a nice alcohol rub down.

Step 10: Addendum

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You may find that your salted out Isopropyl leaves a salt residue when it is burned. In many applications like a pocket stove the salt residue will continue to serve in the role of helping to separate the Isopropyl and the water when water intrusion occurs from dampness, rain or boil overs.

In other applications the salt residue may not be desired. To separate the salt residue from the Isopropyl use a homemade still. In this case your are not distilling an azeotropic solution of Isopropyl and water but rather separating a liquid from a dissolved solid.

The diagram below illustrates the required components for such a still.

Qcks5 years ago
Just gonna add...
If you're having issues with salt residue in your isopropyl, you can limit the solubility of the Sodium Chloride by doping the isopropyl with sodium hydroxide prior to salting it.

This has the advantage of having a solvation effect with the salt and the base (Sodium Hydroxide competes with Sodium Chloride for solvation with the water because both have a sodium cation). Any residual hydroxide compound should burn clean.

The biggest downside is that you might begin to push your isopropyl to undergo a synthesis reaction, but due to it's shape that's not very likely (that is to say, it's stearically hindered, and thus, unlikely to undergo any synthesis reactions).
lpkid1057 Qcks5 years ago
Love the pedantic organic chemistry guy here.