[Cheese_Burgers]

I need some diethyl ether for an extraction. I don't feel like messing around with the synthesis without a blast shield and distilling from starter fluid isn't too safe either. HA.

So, despite how impractical it may be, I've decided to do an extraction from starter fluid with water. My plan is to use a glass carboy because the bottle neck top should make it easier to collect the 50 ml of ether ill get per 5 liters of water. Don't even tell me how tedious and stupid it sounds I know, heh.  I'm using a starting fluid that is advertised right on the front of the bottle as "50% ether", so at least i have that going for me. To extract the ether from the other fraction, containing mostly heptane and pentane Im just going to use a sep.

Once i have ether water to the brim in the carboy, im going to load in a bunch of salt, stir, and put it in the freezer to separate, which im guessing will probably take several hours

What can i do to optimize this process?
-i.e. use sodium bicarb as the salt instead of NaCl or possibly a mix?

Before I waste my time, will this even work?


Lastly, I realize how unstable ether is. My question is, how long until it forms peroxides? I plan on using it immediately after extraction and evaporating it away but there's the time in the freezer and the time the entire process is going to take to consider. Also, hypothetically, I hear Potassium Hydroxide can be added to ether to stop peroxide formation. 1) Is this true? if yes, how much do you add??

Thanks. I appreciate any response.

[Doc Oc]

What are you extracting?  Ether is a convenient solvent for liquid-liquid extraction, but not the only option.

[discodermolide]

I think you are wasting your time. How do you plan to separate the ether from pentane and heptane?
You are dealing with highly flammable materials here, and without the proper facilities you may run into trouble.
Why not just go buy some ether?
I don't advise you to do this at all.

[Cheese_Burgers]

The pentane and heptane are not soluble in water but the ether is slightly soluble. I would use a sep funnel. I would do this outdoors, possibly even cooling the container on ice so i wouldn't have to bring it to the freezer indoors. 

Ether can be used for pretty much anything. Im going to use it to extract and crystalize steviol after i push the alcohol/ steviol tincture made in a soxhlet into water by adding water and distilling off the alcohol. i would then extract the water, then evaporation to get the crystal steviol. hopefully.

[Cheese_Burgers]

im aware of the waste of time, but will it work? I don't feel like buying ether at 35$ per 500ml and pretty much everything a home chemist can do, even with proper equipment is illegal in some way, so i really don't want to be buying a bunch of scheduled chemicals all the time.

Again: So, how long is this stuff stable at room temp before peroxides form? also, if i dry the ether with anhydrous magnesium sulfate or something, will it be less stable? again, does KOH inhibit peroxide formation?

[discodermolide]

Ether peroxides form rather rapidly upon contact with air. You can flush the system with N₂. Peroxides are not base stable, hydrogen peroxide decomposes into water and oxygen in the presence of base. So storage over KOH could well help you here.
Drying it with MgSO₄ does not really alter the stability.

[408]

The solubility of ether in water is really low and this will likely not work.  Just distill it (BUT NOT TO DRYNESS!).  Ether forms peroxides over months and years, not hours, store over KOH for stability

[discodermolide]

My experience with ether is that peroxides form rather rapidly on contact with air. You can monitor it with the Merck starch/iodide strips.

[Cheese_Burgers]

Thanks a lot. Monitoring with starch iodide papers is a great precaution. I wan't to distill or synth but just want to do it safely. For a synthesis or distillation would my .5 meter Vigreux to the .5 meter liebig i have work? (btw i would of course attempt the distillation first) i would only have 350 ml in the pot at a time. I just don't want peroxides to form when it's coming up the vigreux and in the liebig and end up with a fire and glass embedded in me (by the way i should establish that i have a fume hood). What can i put the ether fire out with if it happens, fire extinguisher should work shouldn't it?

[discodermolide]

What's your heat source? Are all the electric connections explosion proof?
Ether fires are usually extinguished with dry powder.

[vmelkon]

I didn't make diethyl ether because I didn't have immediate need for it but I did make chloroform. The bp is 61 °C. I used a 300 mm liebeg. The vapors were reaching the end even though it visually looked like it was all condensing at the beginning of the condenser. The vapors fly! This is nothing like distilling water, methanol or ethanol. I think in the case of diethyl ether, it is going to be nastier.

I think a graham condenser is better than a liebeg since the path is much longer. Keep it pointing down if you can.
If you are going to keep it at an angle, you would have to watch out for suck backs when you turn off the heat.

[408]

What will you be running though your condenser?  Unless you have a very long condenser, you should be circulating a cooling mixture (like salt water at -5) instead of the usual tap water at 20-ish C.

[Cheese_Burgers]

-I'm not sure if my hotplate is explosion proof but i will definitely get one that is if mine isn't.

-I was thinking about putting a downward gram at the end of the liebig to ensure condensation.

-The salt water is a great idea. I think ill experiment with saturated salt water cooled on dry ice over a magnetic stirrer. Well see if the fish pump breaks for some reason..

-I'll be sure to gradually reduce the heat to minimize the possibility of a return


Thanks again for helping to make this safe.  Still going to do a lot of research before I try.

[Ander08]

Yeah i would not suggest this. Diethyl ether oxidizes very easily, and has to be kept in a well sealed container. And The container has to be discarded after a period of time anyway due to peroxide formation. It is way too much work than its worth.