Sciencemadness Discussion Board

Quickly drying mineral oil or storing sodium without mineral oil?

Draeger - 26-3-2021 at 15:08

So, I've bought myself some sodium, and along with it, some mineral oil. Then I wanted to store the sodium in the mineral oil, but it turns out, it wasn't anhydrous. Luckily, I didn't pour in much yet, so, except my sodium maybe being ruined, it seems the reaction is under control.

I'm not sure how to save my sodium though, since I'm not sure how I can dry my mineral oil. I don't have calcium chloride, nor any calcium compound I could turn into calcium chloride. What do I do? Is there maybe a way to temporarily store my sodium without mineral oil?

I know I should've expected something like that, but I didn't expect that for some reason. Next time, I'll know.

RustyShackleford - 26-3-2021 at 15:21

you could store in a flask flushed w butane/propane, if you dont have any other inert gas.

Sulaiman - 26-3-2021 at 23:38

you could use a small sacrificial amount of sodium to dry the oil
then add your nice sample

Deathunter88 - 27-3-2021 at 00:01

Are you sure your mineral oil is that wet? I find it hard to believe a significant amount of water could stay dissolved in mineral oil.

draculic acid69 - 27-3-2021 at 00:59

Or use a solvent like toluene or xylene

Tsjerk - 27-3-2021 at 03:00

The oil I buy always contains a little water, not enough to react with a lot of sodium, but enough to bubble.

Just heat the oil to about 125-150 degrees until it stops bubbling. It will take about 15-45 minutes depending on the temperature.

Unlike when stored under propane/toluene you don't need a very airtight container when using oil. The oil itself will form a seal in the threads or between the fitted glass.
I have a sodium sample with only a very tiny air bubble in a screw cap bottle, it is 15 years old but the metal is still almost shiny, just a bit de-colored, but no oxide crust.

[Edited on 27-3-2021 by Tsjerk]

Draeger - 27-3-2021 at 05:51

Quote: Originally posted by Tsjerk  
The oil I buy always contains a little water, not enough to react with a lot of sodium, but enough to bubble.

Just heat the oil to about 125-150 degrees until it stops bubbling. It will take about 15-45 minutes depending on the temperature.

Unlike when stored under propane/toluene you don't need a very airtight container when using oil. The oil itself will form a seal in the threads or between the fitted glass.
I have a sodium sample with only a very tiny air bubble in a screw cap bottle, it is 15 years old but the metal is still almost shiny, just a bit de-colored, but no oxide crust.

[Edited on 27-3-2021 by Tsjerk]

How much does your's bubble? When I put it upright in just a small puddle of oil, it quickly sucked the whole metal full of it, and when I felt the surface of it with gloves (there was no way they could be wet, I was sure of that), the sodium was quite hot and nowhere near stopping to bubble, despite immediately taking it out of the oil.

unionised - 27-3-2021 at 05:56

Quote: Originally posted by Draeger  
When I put it upright in just a small puddle of oil, it quickly sucked the whole metal full of it, and when I felt the surface of it with gloves (there was no way they could be wet, I was sure of that), the sodium was quite hot and nowhere near stopping to bubble, despite immediately taking it out of the oil.


I don't think you have oil there. You have something else.

You can not dissolve that much water in oil.

Draeger - 27-3-2021 at 07:07

Quote: Originally posted by unionised  
Quote: Originally posted by Draeger  
When I put it upright in just a small puddle of oil, it quickly sucked the whole metal full of it, and when I felt the surface of it with gloves (there was no way they could be wet, I was sure of that), the sodium was quite hot and nowhere near stopping to bubble, despite immediately taking it out of the oil.


I don't think you have oil there. You have something else.

You can not dissolve that much water in oil.

Great. Guess S3 chemicals scammed me then.

Fyndium - 27-3-2021 at 07:16

You order oil from special chemical supplier?

Mineral oil, or paraffin oil is sold in every supermarket either as a baby oil in skin treatment aisle, or oil for treating cutting boards, wood surfaces and other stuff in kitchen aisle, and also in paint aisle for some purposes. I never had any water in my oil, and I've gotten them literally everywhere. My latest oil that I use to grease all my glass joints, stirrer bearings and also for my vacuum pump is actually from IKEA.

S.C. Wack - 27-3-2021 at 08:45

OTC mineral oils tend to have additives.

Draeger - 27-3-2021 at 09:12

Yeah, seems that in my area, mineral oil is a rarity, and impossible to get without additives. Even from my online suppliers, S3 was the only one that sold mineral oil at an affordable price.

Fyndium - 27-3-2021 at 09:23

Strange. The ones that are not for baby treatment, are practically straight paraffin oils without any other stuff. So far I haven't noticed anything else, anyway.

Texium - 27-3-2021 at 10:15

Quote: Originally posted by Draeger  
Great. Guess S3 chemicals scammed me then.
That would be an odd scam to run considering there are few things less expensive than mineral oil...

S.C. Wack - 27-3-2021 at 11:19

Quote: Originally posted by Fyndium  
The ones that are not for baby treatment, are practically straight paraffin oils without any other stuff.


Like this?

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S.C. Wack - 27-3-2021 at 11:23

...

back.jpg - 26kB

Fyndium - 27-3-2021 at 11:39

The stuff that's supposed to be administered on or in humans, usually contains trace amounts of stuff like that E-vitamin. The wood treatment oil is usually just paraffin.

I'm usually not too concerned about some small impurities, because they either do not react or affects yield much less than what it would cost to purify the stuff. If you need pure stuff for example when doing stuff that's very sensitive to catalytic impurities, it's another case, and actual ACS grade stuff might be easiest.

S.C. Wack - 27-3-2021 at 12:48

PS add kerosene to the list, but not the "lamp oil" that turns out to boil at 80C.

zed - 3-4-2021 at 22:49

Ummm. Nurdrage found his Sodium production method, required Hypoallergenic Baby oil.

Aromatics are sometimes a problem, and scents would definitely be a problem.

valeg96 - 6-6-2021 at 05:04

I recently had to clean and store approx. 300 g of sodium for a school. I used high bp petroleum ether for lithium (40-80°C) and rectified petroleum (180-230°C) for sodium, both laboratory reagents. Thankfully I didn't use some opened hexane I was provided with, because there was an inch of water on the bottom of the bottle. I would have blown myself up, had I poured it all in the sodium jar. I have found that even the water that gets absorbed during storage is enough to make the metal fizz; so drying them beforehand with CaCl2 is definitely recommended unless they are brand new.