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Author: Subject: Make Potassium (from versuchschemie.de)
DJF90
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[*] posted on 25-1-2011 at 12:36


No I mean I looked at the paper and copied the point of interest (which was best summarised by the summary, funnily enough).
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[*] posted on 25-1-2011 at 19:15
"baby oil" confirmed working


"Baby oil" grade paraffin has been confirmed to work in a standard reaction with t-amyl alcohol.

Trick is to use "hypoallergenic" variety that is pure liquid paraffin without additives, stabilizers or perfumes.

Density was too low for "floating coalescence" but modest "bubble agitation coalescence" was present.

Speed was fairly pedestrian at ~4hrs.
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[*] posted on 26-1-2011 at 09:57


Nurdrage:

Have you tried the one pot method yet?

I've been off ill the last two days but hope to test a heavy kerosene soon.
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[*] posted on 26-1-2011 at 10:10


So baby oil is able to obtain the 200 degree temperature required

Why would you put that on your baby?




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[*] posted on 26-1-2011 at 12:09


Quote: Originally posted by mr.crow  
So baby oil is able to obtain the 200 degree temperature required

Why would you put that on your baby?


A bit of a silly remark, Mr Crow. Baby oil is almost exclusively paraffins (i.e. alkanes) which by their very nature are quite chemically inert, hence the resistance also to high temperatures. The chemical inertness is however an asset to anything you’d want to rub into a baby’s (or an adult’s for that matter) skin. Simples.

Paraffins have also been used as a laxative and for frying chips (aka 'fries').
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[*] posted on 26-1-2011 at 13:28


I've followed this thread for a while, and it's been extremely interesting. It's a real testament to the skill and dedication of the members of this site, with so many different people researching different aspects of this reaction.

Could we compile a single list (maybe another sticky thread) with all the different solvents, alcohols, etc. that have been found to work? It's time consuming trying to sift through 27 pages of replies :) I really want to try this myself, and I'd like to know what works before I try to hunt down the more exotic reagents like the shellsol and t-butanol. Apologies if this has already been done and I missed it.
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[*] posted on 26-1-2011 at 14:26


It’s not really necessary to compile such a list. Solvents that work need basically to be inert to liquid potassium at 200C and have a sufficiently high BP (range) to allow running them at that temperature. For the most part that means saturated hydrocarbons mixtures: paraffin oil, kerosene (medium or heavy), Shellsol (a ‘branded’ kerosene, essentially), paraffinic baby oil, blends thereof and similar will all do. No-gos are things like silicone oil, glycols, halogenated hydrocarbons and such like because they react with K like the clappers.

T-butanol isn’t ‘exotic’: I’m sure you can buy it unrestricted in the US from many sites. If not try t-amyl alcohol, it’s just as effective. And if you come across perchance of any other tertiary alcohols, ring the ‘Alarm bell’: some here are waiting to test such alcohols…
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[*] posted on 26-1-2011 at 15:42


Thanks for the info. I guess it all sounds pretty exotic to me, since I never deal with organic chemistry. I'll see what I can find. I still need a good hot plate for it though, so that might need to wait depending on cost.
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[*] posted on 27-1-2011 at 18:03


I tend to make lots of silly remarks.

So I bought some of the baby oil in question, says it contains only "paraffinium liquidum" and no fragrances or aloe. I'm wondering how it is different from the regular "heavy mineral oil" sold as a laxative. I hope no one tries to fry chips with it!

So that means I have all the chemicals and equipment. Hopefully the home made Mg powder/turnings works. I can't do it outside, too cold, and probably isn't safe enough to do indoors.

Nurdrage has a list of solvents. t-butanol and 2-methyl-2-butanol both work fine, but the latter is more convenient. Mg particle size is important too, needs to be a powder.

How about the KOH, are 85%+ pellets fine?




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[*] posted on 28-1-2011 at 08:27


Quote: Originally posted by mr.crow  
I tend to make lots of silly remarks.

So I bought some of the baby oil in question, says it contains only "paraffinium liquidum" and no fragrances or aloe. I'm wondering how it is different from the regular "heavy mineral oil" sold as a laxative. I hope no one tries to fry chips with it!

So that means I have all the chemicals and equipment. Hopefully the home made Mg powder/turnings works. I can't do it outside, too cold, and probably isn't safe enough to do indoors.

Nurdrage has a list of solvents. t-butanol and 2-methyl-2-butanol both work fine, but the latter is more convenient. Mg particle size is important too, needs to be a powder.

How about the KOH, are 85%+ pellets fine?


Heavy mineral oil? An elastic term. Suppliers rarely provide density. Baby oil would work as a laxative and in a chip fryer.

Magnesium: chips, powder, it’s mostly all good. Rarely has someone gotten a poor result due to Mg alone. A decent, unadulterated pyro grade should do fine.

KOH: pellets are fine.

Unless you have a dedicated chem area inside, outside is best, some sheltered area I guess. Remember that temperature is ‘the great doubler’ here, you need to maintain 200+C for at least a couple of hours before you even get small globules which might not even be visible because of the formed MgO. Carrying on for 4 to 4 ½ hours is best: may the K-balls be yours!
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[*] posted on 28-1-2011 at 08:44
Concentration dependence of alcohol


I tried the reaction again (baby oil + t amyl alcohol method) and this time i minimized my use of solvent to *just* cover the solids but used the same amount of alcohol. Proportionally by volume the amount of alcohol was probably >20% (stochiometry is still the same though at 10% of Mg).

I also used the one-pot approach put for by blogfast.

Reaction didn't work. the mixture got cloudy and dehydrated but failed the potassium+water test. i did this twice to confirm.

Then I performed the same reaction and added more solvent, so the proportion of alcohol was probably less than 10% by volume. This time the reaction proceeded forward and i had potassium formation.

So i believe this shows a concentration dependence in terms of alcohol. Too high a concentration somehow inhibits the reaction.

So when troubleshooting your reaction consider that a sufficient amount of solvent is needed.

I only really tested with the one pot method. I'm not sure if the same issue occurs with the two step method.
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[*] posted on 28-1-2011 at 13:11


Very interesting Nurdrage. Like you, I’ve been cutting down on solvent somewhat, using 40 ml instead 50 for instance, with no adverse effects. But I didn’t go as far as you did. Your results seem to show that there’s a lower limit of solvent/reagents ratio though.

I’m a little surprised at that result: there’s really nothing in the (proposed) reaction mechanism that would seem to imply too little solvent would be detrimental. And where I’ve increased alcohol content (again fairly modestly) I saw no significant influence on overall reaction time.

At the same time it remains difficult to make definite (theoretical) pronouncements with regards to the influence of the initial concentrations of one or more reagents on the overall reaction rate, without actual equilibrium constants. But even if we had them, calculations would involve a system of partial differential equations with 8 variables: time, KOH, ROH, KOR, Mg(OR)2, H2O, K and MgO…
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[*] posted on 31-1-2011 at 00:49


Just a thought that crossed my mind, as absurd as it may sound, could some t-BuOH loss be accounted for as isobutene gas? It would take severely forcing conditions but perhaps at 200+degC, with t-BuOK as a base and both potassium and magnesium metal being present and able to reduce the eliminated water to hydrogen gas it could happen.

It sounds absurd, but perhaps this could account for why increased contact time with the KOH/Mg, especially during the induction phase could cause reduced yield/increased t-BuOH requirements.

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[*] posted on 1-2-2011 at 08:19


Just so everyone can weigh in on this,

Adding the catalyst at the beginning produces more decomposition side reactions due to longer contact time. This increases water and decreases catalyst concentration.

Isobutene sounds like the product. The easiest test would be to bubble the gas through water/solvent with bromine to test for unsaturation.

Has anyone analyzed the purity of the K?




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[*] posted on 1-2-2011 at 08:51


Aonomus and mr crow:

Sigh…

The catalyst is very stable even at these temperatures and conditions. Adding the catalyst at the beginning makes not a blinding bit of difference, as evidenced by mine and Nurdrage's experiments.

Get experimenting, stop faffing about.


[Edited on 1-2-2011 by blogfast25]
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[*] posted on 1-2-2011 at 09:14


I'm still a little undecided on the right time to add the catalyst.

Sometimes my one-pot experiments fail but then work when i inject more alcohol later. I tend to have more consistent results with timed addition. But this is based on a limited set of experiments. i need to run a dozen times more before i can iron out any patterns with the one-pot approach.

I will say this though: one-pot does work and does give potassium. but i am unsure if it is as good. Nonetheless it is good enough that it should seriously be considered when making potassium. Especially where the inconvenience of injecting alcohol into an assembled apparatus (like a single neck flask) must be dealt with.
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[*] posted on 1-2-2011 at 09:48


Nurdrage:

I haven't had the time I wished I had, following political events around the world. My one test with one pot showed not a blinding bit of difference, in any aspect. I followed that one eyeballs glued to the flask, as it were.

If the proposed mechanism is correct, there nothing in the theory that should make anyone suspect that adding the catalyst at the start is a no-no. I believe that to believe otherwise is merely 'chemical superstition'...
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[*] posted on 1-2-2011 at 10:18


I will not base an entire theoretical construction on your "one test with one pot".

Consistent, reproducible results are far more valuable.

in addition, just because a theory says no one should suspect something doesn't mean we should ignore it without question. It was my blatant questioning of the aliphatic solvent theory that lead me to discover 1,2,3,4-tetrahydronaphthalene (tetralin) to be viable.

I have performed about 6 experiments with the one pot approach, with so far inconsistent results (in terms of time, quality and yield). Quite frankly i trust my 6 vs. your 1 experiment.

I'll make it clear, i acknowledge you *may* be right, and i have not yet decisively proven there is a difference. But without a great deal more data, experiments and verification by others under controlled conditions, for now I outright reject your assertion that there is "not a blinding bit of difference."
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[*] posted on 2-2-2011 at 14:24


Quote: Originally posted by NurdRage  


in addition, just because a theory says no one should suspect something doesn't mean we should ignore it without question. It was my blatant questioning of the aliphatic solvent theory that lead me to discover 1,2,3,4-tetrahydronaphthalene (tetralin) to be viable.

I have performed about 6 experiments with the one pot approach, with so far inconsistent results (in terms of time, quality and yield). Quite frankly i trust my 6 vs. your 1 experiment.

I'll make it clear, i acknowledge you *may* be right, and i have not yet decisively proven there is a difference. But without a great deal more data, experiments and verification by others under controlled conditions, for now I outright reject your assertion that there is "not a blinding bit of difference."


Your reasoning is deeply flawed. When everyone here was still deeply skeptical about pok’s results, it was generally (and correctly) assumed if one person could reproduce his results then we knew pok was speaking the truth (and he was). It’s the same here: my experiment showed that one pot made not a bit of difference.

Your statement about theory is a straw man: I never said such a thing. When theory and experimental results are in line, theory is vindicated and vice versa.

I don’t believe you have carried out 6 one pot experiments without changing any other variables, just like I don’t believe you have carried out 6 not one pot experiments without changing any other variables.
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[*] posted on 2-2-2011 at 19:52


No it is not the same.

When testing the potassium the line of reasoning could be simplified to "Is X possible? if not, it is impossible"

All we needed was one successful replication to prove it was possible, we didn't need to prove it was possible all the time or even if it was exactly replicable. Just that it was possible.

That's a fairly straightforward proof.

Now your statement with "not a blinding bit of difference" is a far taller order.

Simplified its goes something like "Is A not different than B for all cases?". This goes to "Is A = B for all cases?"

Where the cases are yield/rate/purity for all experiments and all reactions conditions provided two experiments are performed identically (A being one-pot and B being staggered addition).

This is NOT something you can prove with just one experiment, because that's only one case. You need to thoroughly test more cases before making reasonable determinations.

That is what i'm currently trying to do, so i think its premature to say "A=B for all cases" is true. You may be vindicated in the future, but i don't think one experiment can say that yet.

I'll settle for "A=B for most cases" as its not very practical to test all cases.

A more narrowly defined, but still very important logic statement is "Can one-pot addition work?" This simplifies to "Is X possible?"

For this you just need one experiment, you've performed one and were successful (lucky bastard! :)), I performed some and was successful in fewer. So yes, we have proven one pot is possible. A billion failures still doesn't prove its wrong, just one success proves it right. Same thing with the original belief in Pok's work.

Is there no difference? I don't know, and i don't think you know either.... or at least haven't proven it to a reasonably acceptable degree.

If the situation were reverse, like we started with one pot and then tried staggered addition later. I'd still argue that there may be differences and a great deal more work was needed to prove otherwise.

I think a better order "is there a practical difference?" This requires very few replicate measurements, and can strongly be supported with just one experiment. Although i'd personally prefer a few more. much more variability can be tolerated.

But i think "not a blinding bit of difference" is too strong a statement to make and believe it vindicated by just one experiment.


As for this: "I don’t believe you have carried out 6 one pot experiments without changing any other variables, just like I don’t believe you have carried out 6 not one pot experiments without changing any other variables."

alright, if you're questioning my honesty or experimental approach, i question your honesty and experimental approach as well. I do not believe your one experiment actually showed "not a bit of difference."

Sounds really broad... Are yield, rate and purity all exactly the same? how did you characterize your results?

in my 6 experiments two of them produced no product at all after 4 hours. One went very fast and produced small balls within 2 hours, finally coalescing after 4 (in total). Yield was extremely variable, 0% to 60%

On the other hand once i got the staggered addition parameters worked out i could make potassium in several replicate experiments with about 40-60% yield every time.

So by my experiments there is "a bit" of difference.

But then again, i may be a liar, or an idiot. Your one experiment clearly proves without the need for replication that one pot will always yield exactly the same results as any other one-pot experiment or staggered addition experiment for that matter.

Replicate experiments are only for liars and/or idiots like myself.

You'd be an awesome drug developer. An old drug works but then you make a new drug and from one test with one patient you find "not a blinding bit of difference." Therefore all patients must react exactly the same way to a new drug as the old drug, no need for clinical trials.

So please ignore my results with tetralin. Clearly past experiments with pure aliphatic solvents working and aromatic containing solvents not working vindicate the aliphatic solvent only theory. I never should have questioned that and tried tetralin.

I officially retract my assertions that tetralin works.
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[*] posted on 2-2-2011 at 22:49


Hey Nurdrage, this is only the internet, you tend to give different phrases used by others too much 'hidden' meaning...
I don't think Blogfast meant anything derogatory... lets not argue and pickle each other on this wonderful thread...

I can't believe that this synthesis hasn't been researched by some team of chemists, properly funded by a university, so that they could determine at least part of the variables and how they affect the outcome. The silence in the literature about this is staggering.




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[*] posted on 3-2-2011 at 00:13


My theories and ideas can be attacked, ridiculed and all the manner of the criticisms applied. That's good science, a truly useful theory will withstand any attack and be strengthened by future experiments. If i turn out to be a complete moron, its about time.

But if my performance and observations are doubted or rejected, bringing into question my honesty or ability, then there is really nothing i can contribute. I have no means of actually proving i really did my experiments and produced my results or observations. Unlike theories and mechanism, another person cannot verify actual performance... well they can, but i doubt anyone will come over here to watch me stare at a flask for 5 hours. I know taking a person's word on faith is generally a bad idea, but without such faith in the contributors of the thread progress would be extremely slow.

Theories can be torn apart left right and center, but data needs a minimal level of trust.

I don't think Blogfast meant anything derogatory, but he does doubt i actually performed my experiments as i describe/imply. If my data is not to be trusted, i no longer see the value in posting it.

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[*] posted on 3-2-2011 at 07:59


Quote: Originally posted by NurdRage  
I don't think Blogfast meant anything derogatory, but he does doubt i actually performed my experiments as i describe/imply. If my data is not to be trusted, i no longer see the value in posting it.



No, I don’t actually (and I didn't say that).

Simple question: did you run 6 experiments with one pot in IDENTICAL CONDITIONS? If not you didn’t strictly speaking replicate. If yes then show us the data: you’ve always been completely transparent before (and I’m not claiming you’re not now either).

And a more specific minor question: did you replicate the Tetralin experiment? There was minor doubt about the experimental conditions as I recall…

***********

As I didn’t see you comment above the one I’m responding to, I can only say ‘calm down’ to that one.

You resorted to literalism there: when a reaction proceeds in exactly the same fashion as any other, the term ‘no difference’ applies. You’re reading too much into what I wrote. But I'll tone it down: 'One pot is possible' is simple statement of fact nad more accurate than my previous statement. Agreed?

*******

I’m not too enamoured with some of your approaches to theory either. Considerably higher up you wrote ‘Experiment > Theory’. That’s quatch.

One of the reasons why I found the one pot method result significant is that although it isn’t PROOF that the theory works but that it certainly counts as EVIDENCE that it does.

Another piece of evidence that I’ve been meaning to generate is to recycle the solvent (presumably with catalyst – partly or wholly as KOR) and run a reaction with that (w/o adding “virgin” catalyst). If the alcohol truly is a catalyst it MUST be recyclable, at least to some degree (losses and degradation need to be taken into account). Some very practical problems have stopped be so far from doing it…

[Edited on 3-2-2011 by blogfast25]

[Edited on 3-2-2011 by blogfast25]
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[*] posted on 4-2-2011 at 07:57


Well I finally got my Merck t-butanol today!
To my surprise it came in a glass bottle.
Isn't there the risk as it keeps freezing and melting to crack the glass?
Right now it's frozen but my room can exceed 26 C.
I can also constantly hear the frozen alcohol make tiny cracks, so I guess it's still in the process of freezing.
Should I move it to plastic or is it fine? How did you guys get your butanol in?




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[*] posted on 4-2-2011 at 08:13


Quote: Originally posted by condennnsa  
Well I finally got my Merck t-butanol today!
To my surprise it came in a glass bottle.
Isn't there the risk as it keeps freezing and melting to crack the glass?
Right now it's frozen but my room can exceed 26 C.
I can also constantly hear the frozen alcohol make tiny cracks, so I guess it's still in the process of freezing.
Should I move it to plastic or is it fine? How did you guys get your butanol in?


Mine is in a 1L glass bottle. It shrinks when it freezes so there is no risk of breaking. Most liquids do this, except water.

When it freezes do you get beautiful needle like crystals forming all over?




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