Sciencemadness Discussion Board - Potassium metal instead of Sodium from dioxane extraction of KMgO?

Potassium metal instead of Sodium from dioxane extraction of KMgO?

RogueRose - 17-10-2017 at 11:58

I was watching Nurdrage's video on how to make sodium metal via distillation of NaMgO in dioxane. The NaMgO is made by burning NaOH and Mg at a specific ratio and then putting the resulting product in a beaker with dioxane and heating for distillation (while stirring). This results in the Na being freed up and floating in the dioxane and is able to be extracted easily afterwards.

I'm wondering if the same process could be done with KOH instead of NaOH and get K metal in the end?

From watching some of the videos with the production of dioxane from ethelyne glycol they use NaOH to remove impurities but state that KOH can be used as well but would remain liquid instead of a solid when using NaOH - so seperation of the dioxane and contaminates would be done via sep funnel instead of decanting with NaOH (contaminates solidify with NaOH). So it seems that KOH reacts differently with dioxane than does NaOH, but IDK if the KMgO would work for K metal extraction.

Anyone have any idea if this would work?

Here is a link to the video:
https://www.youtube.com/watch?v=jCrFFVVcPUI

I'm also wondering if something similar could be done with LiOH or possibly even LiCO3 mixed with the Mg. Each the NaOH, KOH and LiCO3 have BP/decmop points fairly close to each other (within 100C or so) and I'm wondering if extra Mg could be added if more energy is needed for the reaction.

edit - I found this thread and in the comments they discuss KOH and LiOH in place of the Na but it isnt' clear whether it will be successful.
https://www.youtube.com/watch?v=ZXCSL0r4aqg

[Edited on 17-10-2017 by RogueRose]

clearly_not_atara - 17-10-2017 at 13:20

Always shocked when people don't know this, but the potassium synthesis predates the sodium synthesis by several years. It's a sticky for Buddha's sake.

https://www.sciencemadness.org/whisper/viewthread.php?tid=14...

aga - 17-10-2017 at 13:51

Nurdy's sodium synth works fine.

The reasons why dioxane works are unclear.

Personally i think it is something to do with the melting point, where the solid/liquid states are poorly defined in the material due to the temperature being held above, but close, to the melting point, so it easily agglomerates as it loses that important bit of energy when it contacts another blob.

You see the same with a gold melt - get it too hot and it becomes hard to merge all the teeny blobs into a single Big blob.

For K you'll need to find a solvent that boils at about 65 C to try for the same effect.

An idea would to use any unreactive solvent and PID the temperature, although lots of stirring would be required, seeing as it would not be vigorously boiling.

RogueRose - 17-10-2017 at 14:35

Quote: Originally posted by clearly_not_atara

Always shocked when people don't know this, but the potassium synthesis predates the sodium synthesis by several years. It's a sticky for Buddha's sake.

https://www.sciencemadness.org/whisper/viewthread.php?tid=14...

The link in the OP isn't working so anyone who looks dosn't see it!

SWIM - 17-10-2017 at 14:55

Quote: Originally posted by RogueRose

Quote: Originally posted by clearly_not_atara

The link in the OP isn't working so anyone who looks dosn't see it!

I've read that thread, and somebody, (Blogfast?) posted another link later to the procedure after commenting that the original link was broken.
I think the problem was that the guy who came up with it (POK?), got in an altercation with versuchem chemie and deleted his posts.

The other link should still be in there somewhere, but it takes a bit of wading through extraneous matters to find it. POK(?) turns up later in the thread and gives advice on making the reaction work, which is well worth finding if you want to give it a try.

This is the potassium hydroxide/magnesium/tertiary alcohol in high boiling solvent route that makes potassium at just 200C or so.

There's a lot of talk in there about Shellsol60 and decalin as solvents, but if you skip to the end it turns out it even works in high boiling alkanes like lamp oil. (I might be mistaken about that, it's a hell of a thread to read through and I've only done that once)

j_sum1 - 17-10-2017 at 15:25

The two methods are a bit different.

The sodium - dioxane method that Nurdrage reported firstly reacts NaOH with Mg in a thermite-style reaction. Dioxane is then used to make the Na conglomerate.
The Potassium thread reacts KOH woth Mg at a lower temperature in the solvent with a tertiary alcohol as a catalyst.

As I see it, there are two open questions.
1. Could the thermite + dioxane route be adapted to K simply by substituting KOH for NaOH?
2. Could the low temperature route be made to work for Na by using dioxane instead of lamp oil or shellsol/60 or whatever else has been used? (Answering this question might also involve further investigation into suitable catalysts.)

I am not sure that anyone had done sufficient experimentation to answer either of these two questions. For myself I am content to merely have a simple route to these metals. And both look equally difficult from my vantage point. Which is to say that neither of them are overly complicated but both do require an investment of time and effort.

[edit] poor keyboard skills

[Edited on 18-10-2017 by j_sum1]

SWIM - 17-10-2017 at 15:57

Quote: Originally posted by j_sum1

The two methods are a bit different.

The sodium - dioxane method that nurdrage reported firstly reacts NaOH with Mg in a thermite style reaction. Dioxane is then used to make the Na congloerate.
The Potassium thread reacts KOH woth Mg at a lower temperature in the solvent with a tertiary alcohol as a catalyst.

As I see it, there are two open questions.
1. Could the thermite + dioxane route be adapted to K simply by substituting KOH for NaOH?
2. Could the low temperature route be made to work for Na by using dioxane instead of lamp oil or shellsol/60 or whatever else has been used? (Answering this question might also involve further investigation into suitable catalysts.)

I am not sure that anyone had done sufficient experimentation to answer either of these two questions. For myself I am content to merely have a simple route to these metals. And both look equally difficult from my vantage point. Which is to say that neither of them are overly complicated but both do require an investment of time and effort.

There were various attempts to modify the POK process for sodium which failed, but none that I recall at the much lower temperatures you'd get with dioxane as the solvent. (But it sure would be great if it worked at these more modest temps).

The general opinion on the thread seemed to be that the poor solubility of the sodium alcoholate as opposed to the potassium alcoholate was the sticking point, and there was some discussion of manufacturing longer chain tertiary alcohols in the hope that the longer aliphatic tail would solve the solubility problem.

I do not recall if these longer tertiary alcohols were manufactured and tried or not.

I do not recall any discussion of using cresols or other similar compounds as catalysts instead of alcohols, but there may be reasons for this I don't understand. They do, however, have boiling points as high as the reaction temperature so would stay mostly in the pot, and are capable of forming alcoholates(edit: Phenolates, I should have said.) I believe they also survive those high temperatures as well as tertiary alcohols do.

If it is possible to do this reaction at the lower temperature of refluxing dioxane it might also be possible to do it with secondary alcohols as I believe the problem with using them in conventional process at high temperatures was the instability or alcohols with alpha hydrogens at those high temperatures.

Disclaimer: I am working from memory here, and mine isn't the best around.

[Edited on 18-10-2017 by SWIM]

j_sum1 - 17-10-2017 at 16:20

Your memory is largely consistent with mine, SWIM.
Bottom line is there is ample ground for experimentation here. Ultimately good clear procedures would be placed in prepub. I think the methods currently being explored are more accessible, more convenient and ultimately less fickle than electrolysis methods.

vmelkon - 17-10-2017 at 18:26

Quote: Originally posted by RogueRose

I'm also wondering if something similar could be done with LiOH or possibly even LiCO3 mixed with the Mg. Each the NaOH, KOH and LiCO3 have BP/decmop points fairly close to each other (within 100C or so) and I'm wondering if extra Mg could be added if more energy is needed for the reaction.

Why did you mention LiCO3 instead of LiOH?
Could Na2CO3 be used instead instead of NaOH for reacting with Mg dust?

RogueRose - 17-10-2017 at 19:20

Quote: Originally posted by vmelkon

Quote: Originally posted by RogueRose

Why did you mention LiCO3 instead of LiOH?
Could Na2CO3 be used instead instead of NaOH for reacting with Mg dust?

LiCO3? Because of availability and price. I really havent' seen LiOH in very many places but have found the carbonate for $10/lb but haven't seen LiOH listed in many places..

vmelkon - 18-10-2017 at 05:31

Quote: Originally posted by RogueRose

Quote: Originally posted by vmelkon

Quote: Originally posted by RogueRose

Why did you mention LiCO3 instead of LiOH?
Could Na2CO3 be used instead instead of NaOH for reacting with Mg dust?

LiCO3? Because of availability and price. I really haven't seen LiOH in very many places but have found the carbonate for $10/lb but haven't seen LiOH listed in many places..

$10/lb or 22$/kg, that is a good price for Li2CO3.
However, it is best to test with Na2CO3 to see if Mg can reduce the sodium. I don't see why it should not be able to. Some of the Na2CO3 would probably melt due to the high heat (mp about 850 ^oC).

I wonder how it compares to getting lithium from the energizer lithium batteries. Probably the batteries are way more expensive. 4 AA batt go for 14$ to 17$ canadian here.