| Pages:
1
..
8
9
10
11
12
..
66 |
woelen
Super Administrator
Posts: 8012
Registered: 20-8-2005
Location: Netherlands
Member Is Offline
Mood: interested
|
|
Pok, I did not see flashes of light in the test tube. I had one big flash of fire, but I think that is due to ignition of a hydrogen/air mix by some
reacting potassium at the liquid/air interface.
If I read your response, then the magnesium I used must have been quite suitable with its 60 ... 100 um particle size. Using filings for grignard
reactions then is not appropriate, these are way too coarse.
I will try the experiment at a larger scale when the ShellSol D70 arrives. I hope that it arrives before next weekend, otherwise the experiment will
be one week later. I only have the time for 4 hours babysitting such a reaction in weekends.
|
|
|
Arthur Dent
National Hazard
Posts: 553
Registered: 22-10-2010
Member Is Offline
Mood: entropic
|
|
Well this has been encouraging so far! As I mentioned previously, I have a source of t-Butanol that's reasonably inexpensive in Canada, so perhaps I
could buy a 500 ml bottle and split it with one or two folks from north of the border? If anyone is interested, PM me and we'll figure things out.
Right now, I have most of the hardware, but i'll have to find an inexpensive source of KOH and something equivalent to the Shellsol (might as well get
as close to the original recipe as possible to ensure success). I've been measuring the exact setting on my hotplate to get near the range of
temperatures needed for the sandbath. A big thick-walled 500ml bomex round bottom flask will be used instead of an erlenmeyer, will this be ok?
@Pok: Thanks for suggesting this great experiment, this is the most fun thing i've read in a long time!
@NurdRage: Will we see a cool video of this synthesis soon? 
Robert
|
|
|
len1
National Hazard
Posts: 595
Registered: 1-3-2007
Member Is Offline
Mood: NZ 1 (goal) - Italy 1 (dive)
|
|
Well I am as surprised as anyone by this, since I had gotten it completely out of my mind as a pretty distasteful waste of time. So to see this work
in someone elses hands was a bit like seeing Lazarus get out of the grave.
A few thoughts spring in my head.
It cant be that grinding the KOH allowed it to absorb too much water in my experiment because commercial KOH is 10% water anyway. You can get it
anhydrous by holding at 450C for extended periods but the experimenter nor the patent mentions nothing on this. It can only be stored anhydrous in
hemetically sealed (not ordinarily capped) bottles, and again there is no mention of this.
Perhaps the problem is with the magnesium. But I used several types. One was straight from the drill press and totally shiny. Maybe you need a certain
fineness for best results, but SOME potassium should form on the fresh magnesium surface if this is a real reaction - it might not coagulate well -
thats another matter. But a reaction with water should ensue - and there was none.
The most likely explanation for all this is that this is not a mixed phase reaction at all and all the D70 is doing is providing an inert cover. In
this case I got nothing because I stirred all the time. Letting it all settle to the bottom will get the magnesium in contact with the now solid KOH
and react with it solid phase (mediated presumably by addition of the alcohol), here it is better that the KOH be coarse else the Mg has nothing to
'bite' into. In this case youll get better results heating the KOH with Mg solid.
But I still have some niggles.
Potassium reacts with tButanol, this I have done many times to give KOBu. Water is generated. Since it is gasesous at the reaction temperature it
should vaporise. The tBu actually consumes potassium.
Maybe the tBu helps the potassium globules coalesce. But I have tried it many times, and I can not get potassium in D70 to coalesce this way.
Potassium has a surface tension much smaller than sodium. In D70 I can easily break large globules up, but do what you like I can not get them to
coalesce without working within a few degrees of its mp.
And then I have niggles about the potassium. Judging by the dimensions given we have well nigh 4 grams on the photo. If its all from that one run (it
seems to have come from the one flask where you see it), its a near 100% percent yield for the reaction, which is well nigh impossible. It must have
been from several runs.
Then potassium in D70 (I have been making it other ways, but with a 20L bucket of the stuff left around from this failed experiment I have used it to
clean potassium) attracts all kinds of crap to its surface, and needs extensive puryfing. Yet here its absolutely clean. Thats even more amazing for
me that it grows into such large globules.
Then potassium has weak surface tension and all my globules, larger than about 0.5 are flatenned.
Finally after a few hours in shellsol D70 it acquires first a bluish and finally a purple/gray tinge. Presumbaly the photo was taken straight after
formation.
My best judgement is that what we are shown is real and the reason I got nothing is that I stirred and this is a solid phase reaction. (I will check
this). The coalescing into large clean globules I can not explain. I have worked with K in D70 many time, I used t-butanol and never got this kind of
coalescense. I believe its a fluke, maybe a wonder. I think Woelens results are much more fathomable.
|
|
|
NurdRage
Hazard to Others
Posts: 182
Registered: 11-11-2010
Member Is Offline
Mood: No Mood
|
|
Quote: Originally posted by watson.fawkes  |
Example 3 in the patent uses preformed t-amyl alkoxide (called "tertiary amylate" there). Given Nicodem's comment above, it should be readily formed
from KOH and t-amyl alcohol in alkane solution.
As far as tetralin, the same example 3 uses decalin as a solvent, the completely saturated version of tetralin, itself the half-saturated version of
naphthalene. Shellsol D70 is hydrogen-treated to remove aromatics and alkenes; it has little unsaturated content. I have strong suspicion that somehow
this is significant, although I have no particular mechanism to explain why. It might act as a hydrogen scavenger, forcing a side reaction. Double
bonds might significant change solvation energy, or preferentially solvate some species and reduce its reactivity.
I'm all in favor of exploring the parameter space of this reaction, but at the current stage of maturity, I wouldn't take failure with this solvent as
anything like determinative.
On the plus side, the boiling point of tetralin is a bit higher than that of decalin, which will make the reaction faster. Tetralin as a boiling point
right around the lower boiling point of Shellsol D70. That of decalin is in the range of Gamsol, which is easily available and inexpensive in the US.
|
Interesting, i hadn't taken into account the presence of (or lack of) aromatic hydrocarbons. I'll still give it a go on small scale since i don't have
any other high boiling solvents but I won't let failure dissappoint me in that case  thanks for the heads up.
@Arthur Dent
No video soon, i'd like the synthesis to mature a lot before i make a video on it. Ofcourse i'll cite this thread and its contributors.
|
|
|
blogfast25
International Hazard
Posts: 10562
Registered: 3-2-2008
Location: Neverland
Member Is Offline
Mood: No Mood
|
|
Well, my experiment didn’t go to plan and needs improving.
After the initial evolution of gas, presumed but not tested as hydrogen, the cork bung of the ‘refluxer’ kept being pushed out. I now have some
right sized rubber bungs in the mail.
The question then was to abandon or soldier on without refluxer and I chose the latter, this time putting the temperature probe straight into the open
Erlenmeyer. I started heating at 14.35 and gas started to evolve after about 5 mins. This carried on for about 30 mins: the consistency of the KOH/Mg
mix changed substantially, becoming more ‘homogeneous’ presumed due to break down of KOH flakes. Then the refluxer started failing and I carried
on without it.
At 15.00 I reached 190C with a nice boil and started gradually adding the t-amyl alcohol (2-methyl-2-butanol, BP 102C) over a period of about 15 mins.
At about 15.15 the reaction mix reached 200C. Toggling the gas mark slightly between to settings I managed to keep the temperature quite constant and
close to 200C:
Heating to 200C was maintained till 16.00. I saw no perceptible changes in the white/grey mass and no globules of K appeared.
Failure may be due to:
1. t-alcohol distilling off: no K t-amylate formed
2. oxygen: seems rather unlikely; there was a net outflux of solvent vapour all the time
3. magnesium: pok’s is about my size but it has very clearly considerably more surface area: mine’s basically small irregular little cubes. For a
solution/solid type of reaction high surface area could be crucial to achieve some rate of reaction
4. t-amyl instead of t-butyl
5. other.
The stuff is now cooling down and a sample of the cold solid matter will be examined for evidence of elemental K. If none is found I may add a
considerable amount of t-amyl alcohol and reboil.
|
|
|
watson.fawkes
International Hazard
Posts: 2793
Registered: 16-8-2008
Member Is Offline
Mood: No Mood
|
|
While looking up t-butanol data, I came across
this safety card. Under the heading "STORAGE", it says "Fireproof. Separated from strong oxidants, aluminium." My guess is there's something very
exothermic going on, which results in the permanent sequestration of the t-Bu moiety or its destruction.
|
|
|
blogfast25
International Hazard
Posts: 10562
Registered: 3-2-2008
Location: Neverland
Member Is Offline
Mood: No Mood
|
|
@len1:
Good to have you on this thread!
How about the t-alcohol reacting with the KOH to form t-BuO K, which then, as solute, react with the Mg to form K and (t-BuO)2Mg. Something along the
lines of:
Initiation:
KOH + ROH < --- > KOR + H2O
Wherever this equilibrium lies, it may be pulled to the right by:
Propagation:
2 KOR + Mg < --- > 2 K + Mg(OR)2
Which may itself by pulled to the right by:
Termination:
Mg(OR)2 + 2 H2O --- > Mg(OH)2 + 2 ROH
Of the last step at least we can be reasonably sure: Mg alkoxides should be quite prone to hydolysis.
2 KOH + Mg --- > 2 K + Mg(OH)2 overall reaction.
… thermodynamically driven by the lattice energy of Mg(OH)2.
Amazing you can’t get the K to coalesce in Shellsol: I thought that that would be the easy way to faking the whole thing; a dispersion of K and some
plausible looking grit and just wait for it to coalesce, big juicy K blobs. It puts a hole in my falsification theory…
|
|
|
blogfast25
International Hazard
Posts: 10562
Registered: 3-2-2008
Location: Neverland
Member Is Offline
Mood: No Mood
|
|
@Watson:
It basically says the same about 2-methyl-2-butanol...
|
|
|
watson.fawkes
International Hazard
Posts: 2793
Registered: 16-8-2008
Member Is Offline
Mood: No Mood
|
|
| Quote: Originally posted by len1 | | Potassium reacts with tButanol, this I have done many times to give KOBu. Water is generated. Since it is gasesous at the reaction temperature it
should vaporise. The t-Bu actually consumes potassium. |
If it were water, there would be an oxygen
deficiency. The gas is hydrogen, as listed on wikipedia page for t-BuOH. A footnote on that page points to an OrgSyn prep that begins with preparation of t-BuOK; this prep verifies hydrogen.
|
|
|
blogfast25
International Hazard
Posts: 10562
Registered: 3-2-2008
Location: Neverland
Member Is Offline
Mood: No Mood
|
|
My cooled gunge doesn't react with water at all: the magnesium would even be recovable if the quantity justified it. There's not a fizz, a cackle, a
bit of effervescence or a spark to been seen. Total failure.
Next attempt with better set up and t-butanol...
|
|
|
blogfast25
International Hazard
Posts: 10562
Registered: 3-2-2008
Location: Neverland
Member Is Offline
Mood: No Mood
|
|
We may have to resort to buying some of pok's magnesium (from the stock that He Actually Used) for a kind of Round Robin test... Whatever 'magic', it
doesn't seem to reside in the Shellsol because woelen didn't use that...
I really think we need to postulate mechanisms to try and improve on...
At versuchschemie.de they seem to have given up the ghost altogether: zero activity on chemical K...
[Edited on 13-12-2010 by blogfast25]
|
|
|
len1
National Hazard
Posts: 595
Registered: 1-3-2007
Member Is Offline
Mood: NZ 1 (goal) - Italy 1 (dive)
|
|
@blogfast Yes I saw your theory, and that would be a good proposal except that in that case its a liquid phase reaction and my attempt with the milled
magnesium should have produced SOMETHING. The only hope I really have left for success, and that this is not a hoax, is that the Mg and KOH must be
allowed to come in solid contact with the tBuOH breaking the final thin D70 barrier.
As you say there is nothing special about D70. Just some hydrocarbons that boil at 190C - has a slight smell to it. I would prefer paraffin oil which
doesnt smell, but to be sure I went out of my way to get shellsol those years ago.
Potassium will coalesce in D70, in fact its better in coalescing in it than in parafin because its less viscous, but only mechanically and only near
its solidification point arount 64C. If you try that at higher T's the K is too visocus and the globules just slip past each other no matter how you
try to push them together.
Falsification - that would have to be bloody stupid because this is one of the simplest experiment one can do - especially now that stirring is not
required. He says you must file the Mg not drill it - fine I will invest today in a new file (all mine are slightly rusty) Ill use a single neck
erlenmeyer with a liebig vertical reflux (you need no more for reflux at 190C) and argon flow at the top, with D70 and tButanol and will have an
asnwer at the end of the day one way or another.
|
|
|
Pok
potassium Prometheus
Posts: 176
Registered: 5-12-2010
Member Is Offline
|
|
| Quote: Originally posted by len1 | | It cant be that grinding the KOH allowed it to absorb too much water in my experiment because commercial KOH is 10% water anyway.
|
Yes. But maybe during grinding you raised the water content from 10% to 20%  .
| Quote: Originally posted by len1 |
You can get it anhydrous by holding at 450C for extended periods but the experimenter nor the patent mentions nothing on this. It can only be stored
anhydrous in hemetically sealed (not ordinarily capped) bottles, and again there is no mention of this. |
People normally expect from others to handle hygroscopic chemicals adequately (this includes grinding them hermetically by ball mills for instance). I
think they didn't mention to dry the powdered KOH because they either bought dry KOH powder - or they didn't grind it. In any case, they just expect
from others to be conscious that KOH is highly hygroscopic and only a dry preparation will ensure a water content like the bought chips.
| Quote: Originally posted by len1 | | And then I have niggles about the potassium. Judging by the dimensions given we have well nigh 4 grams on the photo. If its all from that one run (it
seems to have come from the one flask where you see it), its a near 100% percent yield for the reaction, which is well nigh impossible. It must have
been from several runs. |
On the photo you can see ca. 3 grams - smaller K balls also were in the mix but not shown on the photo. This is from one run! Its about 70-80% of
theory.
| Quote: Originally posted by len1 |
Then potassium in D70 (I have been making it other ways, but with a 20L bucket of the stuff left around from this failed experiment I have used it to
clean potassium) attracts all kinds of crap to its surface, and needs extensive puryfing. Yet here its absolutely clean. Thats even more amazing for
me that it grows into such large globules. |
In the liquid state my potassium also attracted some unreacted Mg filings but nothing else. And when the Mg was used up nothing was attached to the K.
| Quote: Originally posted by len1 |
Then potassium has weak surface tension and all my globules, larger than about 0.5 are flatenned. |
My largest balls were about 3 cm in diameter. Even these were almost round and not flattened. The density of K (0.856) only is slightly higher than
that of the Shellsol (0.79), so even at weak surface tension K will form balls (this is what I experienced). If your K in your Shellsol really
flattens due to gravity - are you sure that you have Shellsol  or potassium
?
| Quote: Originally posted by len1 |
Finally after a few hours in shellsol D70 it acquires first a bluish and finally a purple/gray tinge. Presumbaly the photo was taken straight after
formation. |
Yes. The photo was taken only about some minutes after taking it from the reaction mix into clean shellsol. After some days it becomes bluish and
gray.
| Quote: Originally posted by blogfast25 |
Amazing you can’t get the K to coalesce in Shellsol: I thought that that would be the easy way to faking the whole thing; a dispersion of K and some
plausible looking grit and just wait for it to coalesce, big juicy K blobs. It puts a hole in my falsification theory…
|
To be honest, your theory isn't so much affected by lens statements. A guy on versuchschemie.de once was successful in trying to get smaller K balls
coalesce.
http://www.versuchschemie.de/topic,8254,0,-Natrium-Kalium-Le... - compare photo 2 with 4 - he just added some isopropanol to the molten K (under
petroleum - which should have comparable properties like Shellsol D70). I personally never tried this. Maybe this is a possibility to get larger K
balls from a finely devided K suspension in the reaction mix.
My magnesium isn't magic . I think, if you do it like me you will get my results
as well.
I must admit that I really was very lucky since the photos from the 50ml run are those of my first procedure ever! ...if it wouldn't have worked I would probably have given up and never tried it again.
These modifications just worked at the first time:
- not grinding KOH chips
- no temperature control
- Mg of suitable surface area (size)
- no stirring
[Edited on 13-12-2010 by Pok]
|
|
|
blogfast25
International Hazard
Posts: 10562
Registered: 3-2-2008
Location: Neverland
Member Is Offline
Mood: No Mood
|
|
| Quote: Originally posted by len1 | @Potassium will coalesce in D70, in fact its better in coalescing in it than in parafin because its less viscous, but only mechanically and only near
its solidification point arount 64C. If you try that at higher T's the K is too visocus and the globules just slip past each other no matter how you
try to push them together.
Falsification - that would have to be bloody stupid because this is one of the simplest experiment one can do - especially now that stirring is not
required. |
Are you saying that K becomes more viscous at higher T? Most liquids, Newtonian or not, have a decreasing newtonian viscosity v. increasing
temperature function, usually an exponential relationship...
Falsification: I mean of course that it's possible pok couldn't get the patent to work either and for some (immaterial) reason decided to fake the
results. With coalescing K at hand there would be no need for extensive photoshopping...
|
|
|
Jor
National Hazard
Posts: 950
Registered: 21-11-2007
Member Is Offline
Mood: No Mood
|
|
blogfast25, nice that you have also done the experiment.
I still think that a highly likely cause for the failures is that as soon as the t-alcohol hits the surface if the very hot hydrocarbon, it boils of
instantly. Because KOH is insoluble in these kind of solvents (at least I expect it's solubility as nearly zero), no or hardly any salt of t-alcohol
can be formed, because the KOH is at the bottom of the vessel and not at the surface.
I think this could be solved by adding the t-alcohol at the surface of the KOH, adding the t-alcohol to the mixture when the reaction mixture is not
yet at the boiling point (when it's hot I suspect that the K-salt of the alcohol is formed as well, maybe not as fast, but it doesn't matter as it
doesn't boil away). After the K-salt is formed, this is no longer volatile, and you can start to heat up. Also some sodium or potassium salt of
t-alcohol could be added to the mixture instead of the alcohol to prevent it from boiling away.
Also, maybe the water present in the KOH reacts with the K-butylate forming the alcohol (wich boils off) and KOH.
If this were true, there would be the following reaction:
H2O + t-BuOK <--> KOH + t-BuOH
As the H2O is strongly bound to the KOH (KOH will only go anhydrous at very high temperatures), t-BuOH is the only volatile component in the system
and will thus quite fast be removed from the system (ok, it will be condensed, but always some is lost, eventually you will lose all). I think the
only way H2O is removed from the system is by the reaction with any formed K-metal. So even if some K-metal is formed, it will react with the H2O,
greatly diminishing yields. Now the question is, will Mg react with water in KOH at those temperatures, wich ofcourse also depends on the contact of
the KOH and Mg, wich is likely to be very small (unless you use very fine powdered Mg), having two solids.
Maybe a reason for the succes of Pok is that he used very efficient condensing (wet towels) preventing escape of alcohol, while the other reaction
(formation of K, followed by reaction with water) removed all H2O before all t-alcohol was removed from the system. So I recommend very efficient
condensing. Or better use dry KOH (so fuse at high temperatures for some time (nickel crucible or maybe steel)), cool down while covered, and
immediately transfer the dry KOH to the flask filled with Shellsol D70, wich is dried with some Na. if you want to work really dry, you could transfer
the crucible with fused KOH to a clear plastic bag, together with flask containing the dry Shellsoll D70 and a small amount of P4O10 to dry the
atmosphere, and close the bag. Then transfer the KOH to the Shellsol. Or you can use a glovebox
I am only looking for reasons why it doesn't work most of the time, so some might be wrong, but i think the reason is the H2O in KOH, wich is strongly
bound to the KOH, thus shifting the equillibrium to the right side of the above equation.
Woelen, I think your experiment confirms the formation of potassium, but we don't know how much. If you try it again, and you can't extract potassium
out of the mixture can you try to determine how much K is in there by covering the mixture with some inert solvent (ligroin) and adding some
isopropanol . If it is present hydrogen will be produced in a safe manner, and you can collect the gas formed in a inverted cylinder and calculate the
amount of potassium present. If this is a acceptable amount, you can focus on a way to isolate it from mixture. Trying to collect something if you
don't know how much there is (maybe it's only a very small amount of K) makes no sense.
[Edited on 13-12-2010 by Jor]
|
|
|
len1
National Hazard
Posts: 595
Registered: 1-3-2007
Member Is Offline
Mood: NZ 1 (goal) - Italy 1 (dive)
|
|
Pok I think you have misunderstood me. That KOH contains 10% water is not a reflection on anyones skill in handling chemicals, its just a fact of this
world. I have ground and not ground KOH many times, the water content is always in the 10-12% range so that (if it is not a joke) is not so.
As for potassium, if its perfectly round and not flatenned at 3cm diameter its not pure potassium, which would be the case if KOH was contaminated
with even 10% NaOH, changing its properties drastically. The potassium I use is >99% pure (I have IonicC analyzed it) so theres no problems there.
Let alone the above statements be also interpreted personally, as forumers have a propensity to do, let me at once state I intend them as facts of
life as they are written, and not in some sort of subtextual ego statement.
|
|
|
len1
National Hazard
Posts: 595
Registered: 1-3-2007
Member Is Offline
Mood: NZ 1 (goal) - Italy 1 (dive)
|
|
Sorry blogfast that was a typo. I meant less viscous. I have read about using isopropanol or butanol to coalesce Na and K. But I must say I must have
tried it 5-6 times all without success. It produces a brown gunk on the metal surface which must then be removed by more complicated means.
A 70-80% yield from a solid state reaction? - that I do not believe. You can only get this if its a liquid-solid interaction which my previous
experiments preclude - because stirring would aid the reaction in that case. It would only hinder it if this is a solid-solid reactio.
And I have been thinking further. What are these 3cm balls of K you talk about? Thats about 14gms - yet you claim you made 3gms? The other times you
ran the reaction you say you only got small globules. That means you must have coalesced them, yet it is clear from what you write that you do not
know how to do that.
Then why are the K balls perfectly shiny? The reaction produces water too. And fine MgO which should stick to the K surface like glue. Then I have
made potassium t-butoxide before, its solubility in hexane is tiny - in D70 even less, I dont see how this can be a solid-liquid reaction. I am
tossing up whether to try this. It seems almost a guaranteed waste of 4-5 hours, and Ive been had by this reaction already. Probably the round shiny
balls we are seeing are woods metal. All indications to me are that at least a large part of this is bogus. Mind you fairly eloborate bogus, thats
what got me to believe in it at first.
[Edited on 14-12-2010 by len1]
|
|
|
Pok
potassium Prometheus
Posts: 176
Registered: 5-12-2010
Member Is Offline
|
|
| Quote: Originally posted by len1 | | Pok I think you have misunderstood me. That KOH contains 10% water is not a reflection on anyones skill in handling chemicals, its just a fact of this
world. I have ground and not ground KOH many times, the water content is always in the 10-12% |
I know this. But if you grind the commonly available 10% water containing KOH in normal air, it will absorb water from the air and the 10% water
content will rise up to 10+x%.
| Quote: Originally posted by len1 |
As for potassium, if its perfectly round and not flatenned at 3cm diameter its not pure potassium, which would be the case if KOH was contaminated
with even 10% NaOH, changing its properties drastically. |
"Perfectly round"? Who claimed that?? I said that my largest balls were "almost round". You can see it here http://www.versuchschemie.de/upload/files3/64730229_4948.jpg
Not pure potassium?
My KOH is techn. pure. It will contain much much lesser than 5% Na. A probable worst case alloy of 95% K and 5% Na wouldn't affect the density so much
that it could form round balls instead of flattened balls. And even if it would effect it: Na is more dense than K: so an alloy would most probably be
even more flattened than pure K. My produced K burns with a brillant purple flame without any trace of yellow Na light. It has a
melting point of exactly that of literature potassium (+-1°C for measurement reasons). An eutectic alloy of Na an K has a melting point below room
temperature! Sodium impurities would strongly decrease the melting point. Sodium also isn't produced as easily as potassium in this method (see
examples for sodium in the patent). I'm sure my K contains 0.00% Na ...OK,
maybe 0.01% Na.
Its not a solid state reaction.
Thats what it is.
From a 6 times larger procedure (look at thread).
No. Thats 12 gms. And: only an estimation of size!
("about 3cm in diameter" I said).
In my first experiment ever: 50ml procedure with 3g K outcome.
In a 6 times larger experiment: 18g outcome. Maybe only 2.5cm diameter = 7 grams = easily credible.
| Quote: Originally posted by len1 |
The other times you ran the reaction you say you only got small globules. That means you must have coalesced them, yet it is clear from what you write
that you do not know how to do that. |
You obviously didn't read all my comments. I did it several time in 50ml scale, several times in 300ml scale. 50ml always worked. 300ml worked at the
first times, but later: only small globules which didn't coalesce.
Nice, uh?
No. Hydrogen.
Why like glue? It's not fine. The MgO forms crusts!
| Quote: Originally posted by len1 |
Then I have made potassium t-butoxide before, its solubility in hexane is tiny - in D70 even less |
Thas why the reaction takes so much time!!!!
Yeah. Probably, probably, probalby....probably you made some mistakes in your experiment??? 
--- I try to answer questions. But if your next question is "Is this really an erlenmeyer in which you did the reaction? I assume its a tea cup" -
then I will not answer anymore. For me, this is a waste of time. I wanted to give the people on versuchchemie a new method for potassium synthesis. I
was INVITED to come to sciencemadness. I said "OK" - But if you, by all means, just want to believe that I made a
hoax - I don't care anymore. You will be able to get my results if you simply simply do what I did. Some of you will
do this and then I can go home ---
[Edited on 14-12-2010 by Pok]
|
|
|
watson.fawkes
International Hazard
Posts: 2793
Registered: 16-8-2008
Member Is Offline
Mood: No Mood
|
|
| Quote: Originally posted by len1 | | A 70-80% yield from a solid state reaction? - that I do not believe. You can only get this if its a liquid-solid interaction which my previous
experiments preclude - because stirring would aid the reaction in that case. It would only hinder it if this is a solid-solid reactio.
|
Your previous experiments do not preclude a liquid-solid reaction. They might preclude one with products of
indefinite lifetime, but not such an interaction with products of short lifetime. Your earlier results preclude certain simplistic models of the
process, but nothing about this process leads me to believe that there is a simplistic explanation. It seems apparent to me that some ordinary,
normally silent, assumption is false here, and it's always difficult to question an unstated premise.
This has been bothering me for a while, ever since Nicodem posted about acid-base interactions in this context. It seems clear enough that on the K
side, there's formation of t-BuOK in a liquid-solid interaction. The t-BuOK becomes partitioned into different phases, a certain amount as solute and
vapor at least, possibly also some non-dissolved t-BuOK, perhaps as an emulsion. Whatever goes on at the Mg surface, it seems to be interacting with
at least one of these phases, or even some derivative of t-BuOK formed at the surface; even a vapor phase of t-BuOH isn't inconceivable. In addition,
the patent discloses the use of an alkoxide instead of an alcohol. All this seems to diminish the likelihood that solid-solid contact of KOH and Mg is
critical.
On the other hand, however, it does seem to be the case that KOH and Mg need to be in intimate contact, but that does not imply, not in any singular
way, that solid-solid contact is the reason for this. An alternate hypothesis is that something at the Mg surface produces a substance/state that
quickly decomposes in solution, and so it has to have a short solvent-path to a KOH surface before it becomes something other than a reactive species.
This would have similar external requirements on geometric configuration for success as solid-solid contact would require, but not require solid-solid
contact itself.
I don't have particularly satisfying options for what the short-lived varieties might be. It might be a compound that undergoes a reaction. It might
be an adduct that separates. A reaction at the Mg surface seems to require two necessary components, though: (a) Electron transfer from the
half-reaction Mg -> Mg(2+) + 2 e(-) and (b) overcoming the lattice energy of Mg in its crystal. Another possibility, one I find unlikely, is that
Mg comes off the crystal without ionizing; how would that happen? Degradation of an intermediate with respect to Mg has three possibilities (1) Mg(2+)
reduces as a free Mg atom (presumably reactive), (2) Mg(2+) reduces and attaches back to an Mg crystal, (3) Mg(2+) remains bonded to something, even
if it wasn't bound to before. In case (2), that would tend to change the surface structure of the Mg; if anybody has a spare electron microscope to
take a peek, do speak up.
|
|
|
condennnsa
Hazard to Others
Posts: 217
Registered: 20-4-2010
Location: Romania
Member Is Offline
Mood: No Mood
|
|
I think woelen proved beyond a doubt that this reaction yields potassium.
Eversince I first read Poks synthesis on versuchschemie, I believed it's real . The reason I had was because he said at the end "I am extremely
proud of my so easily and cheaply produced potassium and expect praise!! " I reckon a forger would not say this
|
|
|
blogfast25
International Hazard
Posts: 10562
Registered: 3-2-2008
Location: Neverland
Member Is Offline
Mood: No Mood
|
|
| Quote: Originally posted by condennnsa | I think woelen proved beyond a doubt that this reaction yields potassium.
Eversince I first read Poks synthesis on versuchschemie, I believed it's real . The reason I had was because he said at the end "I am extremely
proud of my so easily and cheaply produced potassium and expect praise!! " I reckon a forger would not say this |
Unfortunately that's exactly what a forger would say, IMHO. You're trying to read pok's mind: can't be done. To maximise the credulity of the already
credulous is much easier than you think.
I remain agnostic until my own set of experiments and hopefully someone else's decide either way.
One way forward would be for pok to make available the two most variable ingredients in Goldilock's Mix: the magnesium and the KOH.
Other than that, this is fast risking to become Backyard Science's own 'Cold Fusion'...
[Edited on 14-12-2010 by blogfast25]
|
|
|
blogfast25
International Hazard
Posts: 10562
Registered: 3-2-2008
Location: Neverland
Member Is Offline
Mood: No Mood
|
|
@jor;
Absence of alcohol/too short a time presence of alcohol is a likely cause of failure in my case, I agree. If oxygen had been the cause, I should by
rights have found a mix of Mg(OH)2 and K2O/KOH, without or with much less Mg. But it was clear that apart from the initial driving off of water (as
H2, probably) not a g-ddamn thing happened. My next one will be hermetically sealed, so to speak...
|
|
|
Pok
potassium Prometheus
Posts: 176
Registered: 5-12-2010
Member Is Offline
|
|
| Quote: Originally posted by blogfast25 | | One way forward would be for pok to make available the two most variable ingredients in Goldilock's Mix: the magnesium and the KOH.
|
Do I understand this correctly: you want me to send you some of my Mg and KOH? If yes: I could do it (send me some money for shipping! ). But you shouldn't waste your money for shipping costs. I'm absolutely sure
any 98-100% Mg of suitable size will do it. And I got my KOH from ebay. Any good technical KOH will do it, I'm sure.
The patent doesn't specify the purity or size of KOH / Mg. This indicates that there isn't any hidden and difficult mechanism with other catalysts
than t-butanol. I think the mechanism is absolutely simple: somehow the mechanism that you (blogfast25) assumed once.
I really made it some times successfully. And therefore I can't imagine that the experiment depends on a special method or so:
most important:
- avoid oxygen
- add the t-butanol gradually (within 30 min)
- ensure totally reflux of t-butanol
- stirr occasionally, not continiously
- don't grind KOH chips, add them as they are (qickly taking, weighting and putting into shellsol/Mg mix - to avoid water absorption
from air)
and:
- use t-butanol (quite pure)
- use shellsol D70 (quite pure)
- use 20-50µm Mg (quite pure)
PS: I'll be back next year or so - or if I see the first pictures of large K balls here . I think my presence isn't needed anymore. Read the patent, read versuchschemie.de, read here: you will do it - if I forgot about this thread: keep me in mind as the hero who gave you somehow the
"gold of the hobby chemists". - have a nice chrismas ....
[Edited on 14-12-2010 by Pok]
|
|
|
blogfast25
International Hazard
Posts: 10562
Registered: 3-2-2008
Location: Neverland
Member Is Offline
Mood: No Mood
|
|
pok:
If no one here, to the best of their abilities, can reproduce your results, then we may have to assume that some ‘hidden parameter’ is lurking in
the specific ingredient mix that YOU (and ONLY you used). In that scenario, I would pay for cost of chemicals (KOH + Mg – Shellsol D70 I have and
must be presumed same as yours, “good” t-butanol should also be the same as yours) and shipping from Germany to UK, in order to try and lay this
controversy to rest for once and for all.
But for now no one has really replicated your conditions accurately, not me either and not woelen. len1 came extremely close to the patent conditions,
bar the high speed stirring but didn’t get a semblance of K, not even a trace…
You keep saying that we should be able to reproduce your results easily but right now we don’t even have a plausible mechanism by which this
reaction is supposed to proceed. My own postulate is quite flawed. And I don’t believe in a low temperature solid state reaction…
Yes, Merry Xmas to you as well...
[Edited on 14-12-2010 by blogfast25]
|
|
|
len1
National Hazard
Posts: 595
Registered: 1-3-2007
Member Is Offline
Mood: NZ 1 (goal) - Italy 1 (dive)
|
|
Potassium balls that size are not even 'nearly round '.
Im not even going to reply to his post further since this is obviously a troll, and feeding them is what keeps this going but and interesting thought
is that the original patent is bogus .. and Pok's bogus. Could it be the same bogus? The expired patent holders are from Germany, and whoever posted
this prank on versuchschemie obviously also knows German. In this case his name would be one of the three gentlemen on the patent ..
|
|
|
| Pages:
1
..
8
9
10
11
12
..
66 |
![[*]](images/xpblue/default_icon.gif){kind=icon}
