Pok
potassium Prometheus
Posts: 176
Registered: 5-12-2010
Member Is Offline
|
|
A special chemiluminescence reaction - who knows it?
I found some videos showing a fascinating chemiluminescence (CL) reaction which is absolutely unknown to me. Unfortunately, there isn't any
description how this reaction works and which chemicals are involved.
I think, all three videos are based on the same reaction:
http://www.youtube.com/watch?v=VSXNW3L-8-o
http://www.youtube.com/watch?v=o8OTjf92wZs
http://www.youtube.com/watch?v=JZXBe2SvLPU
You can see that a "gaseous catalyst" (I doubt that this term really is correct) is involved. It's a colourless liquid which can act in the liquid and
gaseous state on the red/orange colored substance. In the first video 2 layers can be seen and the upper layer becomes turbid as the reaction goes on.
The heavy drops which fly out of the beaker may also be produced by heat (exothermic, I don't know), but it's definetely CL and no thermal radiation.
I have no experience with the very bright CL which can be produced with TCPO or similar stuff. So maybe these can be used to make such effects (?).
Does anyone know this reaction? I think, this should already have been mentioned in the literature, so is there a paper that deals
with this reaction? My only guess would be: ruthenium bipyridyl - but this is probably wrong...
A second user shows a very similar reaction. Probably the same:
http://www.youtube.com/watch?v=Yvka3mBMzE4
(similar to the first video above but I don't see 2 layers here). The language sounds french. Does someone understand what they are saying?
I already asked both users, but dind't get an answer yet.
|
|
|
Mailinmypocket
International Hazard
Posts: 1351
Registered: 12-5-2011
Member Is Offline
Mood: No Mood
|
|
Perhaps it is this?
|
|
|
Marvin
National Hazard
Posts: 995
Registered: 13-10-2002
Member Is Offline
Mood: No Mood
|
|
Searching youtube for Ruthenium Chemiluminescence produces a few similar demonstrations so it looks like that is right. A really impressive reaction.
|
|
|
IrC
International Hazard
Posts: 2710
Registered: 7-3-2005
Location: Eureka
Member Is Offline
Mood: Discovering
|
|
Good link. Backspace to the demosheets folder to get the index page. Many great demonstrations such as the Singlet Oxygen link below. Also one not
completed yet for Acridinium Chemiluminescence.
http://chemed.chem.purdue.edu/demos/demosheets/5.12.html
"Science is the belief in the ignorance of the experts" Richard Feynman
|
|
|
Pok
potassium Prometheus
Posts: 176
Registered: 5-12-2010
Member Is Offline
|
|
I have some experience with Ru-bpy chemiluminescence and I have seen several videos and photos of many different systems with Ru-bpy. But none of them
is nearly as bright as these ones. Also, the light of Ru-bpy is always orange/red and not as yellow as in these videos.
Someone else had the idea that this may be a variety of the typical oxalate CL (DNPO or similar with peroxide and rhodamine) and the added catalyst
might be ammonia (solution and gas). As I have no experience with oxalate CL, do you think that this is possible and can you give further evidence -
or can you exclude this idea?
[Edited on 12-8-2013 by Pok]
|
|
|
Dr.Bob
International Hazard
Posts: 2734
Registered: 26-1-2011
Location: USA - NC
Member Is Offline
Mood: No Mood
|
|
The description of the first video says "Rhodamin 6G and Oxalylchloride". So it might make some oxalate type reaction, which makes the
Rhodamine glow.
The second looks similar, maybe with oxalyl chloride fumes
The last looks like the standard oxalate chemistry, only with the dye and catalyst already on a paper towel and the oxalate poured one it.
All great demos, but they need some explanation to be more useful to teach science.
|
|
|
woelen
Super Administrator
Posts: 8014
Registered: 20-8-2005
Location: Netherlands
Member Is Offline
Mood: interested
|
|
@Pok: I have a few grams of bipy and I have RuO2. Which is the chemical you used for the fluorescence reaction? Can I make and isolate some of this
chemical from the compounds I have? When I read this in this thread, I was quite surprised and would love to try such a spectacular reaction myself,
but I do not want to spoil much of these very rare and expensive chemicals on endless testing and trying and on attempts to isolate microquantities
from some vague mix. If you could point me to some paper or site with information about making the required complexes, then that would be very nice.
|
|
|
Pok
potassium Prometheus
Posts: 176
Registered: 5-12-2010
Member Is Offline
|
|
@Dr.Bob: thanks for this info! I asked the uploader via private message but obviously he only answered it in the public. I wouldn't have recognized
this without your advice. The info is sufficcient to me. Your explanation seems very plausible. Unfortunately, I don't have oxalyl chloride. But the
most important thing was the uncertainty. And that's gone. :-)
@woelen: these videos aren't mine. Or do you refer to my experience with ruthenium bipyridil? http://www.versuchschemie.de/topic,17712.html This is one possible experiment with Ru-bpy. In my opinion it's one of the best looking. I also
described how to make the complex. But you will have to convert the Ru oxide into RuCl3. If you have further questions about this, you could go to
versuchschemie.de and discuss it there if you want. Of course, I can tell you the details in this thread here, too. A slightly different method to
make Ru-bpy can be found here: http://illumina-chemie.de/tris-%2822%B4-bipyridyl%29-rutheni... It takes very long and a slight argon stream is required.
There is an experiment that looks similar to the videos I linked here. But the ruthenium "drop glow" experiment is much much weaker than the oxalate
CL! It's simply not possible to produce such a strong effect with ru-bpy. A description for the ruthenium "drop" experiment can be found here: http://www.chem-page.de/showexperimente/71-chemolumineszenz-... (this site always takes some time to load). You will also need PbO2 and NaBH4
besides the Ru complex for this experiment.
People that want to repeat the oxalyl chloride video can make the required oxalyl chloride in a quite difficult procedure like this:
http://www.versuchschemie.de/ptopic,217584.html
phosphorus pentachloride (http://www.versuchschemie.de/ptopic,124916.html) is required. It's (quite difficult) preparation is the key. But the yield of oxalyl chloride will
always be extremely low!
The german links can be translated with google if required.
[Edited on 22-8-2013 by Pok]
|
|
|
woelen
Super Administrator
Posts: 8014
Registered: 20-8-2005
Location: Netherlands
Member Is Offline
Mood: interested
|
|
Thanks for all the links. German is no problem for me, I can read that fluently and if necessary, I can also write some German as well. I have an
account on versuchschemie.de, but I didn't use it for quite some time anymore (after the German mass raiding of home scientists in 2009 I decided to
leave this).
I'll have a look into all the Ru-bipy links and if I can do interesting things with it, I certainly will come back on the subject. I also have NaBH4
and PbO2, so there is a good chance that I can repeat some of these things. The most difficult part probably is making the Ru-bipy complex and the
required apparatus for doing so.
|
|
|
Pok
potassium Prometheus
Posts: 176
Registered: 5-12-2010
Member Is Offline
|
|
Quote: Originally posted by woelen  | | The most difficult part probably is making the Ru-bipy complex and the required apparatus for doing so. |
If you have hypophophorous acid or a salt of this acid, it's not difficult. You don't need argon in this case. The description how to make the complex
with sodium hypophosphite, RuCl3 and bipy can be found in the first link I posted. But for very small quantities (maybe < 100 mg RuCl3 as an educt)
this method might be unsuitable, because a recrystallization process is involved which could be difficult for extremely small quantites of product.
BTW: the mass raiding in Germany had nothing to do with the forum versuchschemie.de. Some (very few) of the forum users just bought monitored
chemicals at suspicious sellers. Only the sellers have been observed and their customers were haunted. But no single guy was haunted just for beeing
member or discussing at versuchschemie.de.
|
|
|
woelen
Super Administrator
Posts: 8014
Registered: 20-8-2005
Location: Netherlands
Member Is Offline
Mood: interested
|
|
I now read all the links and I can only say WOW! This is true home chemistry. Remarkable! Making PCl5 from red P and chlorine also is a very nice
experiment and maybe something I will try in the near future (although I have a small quantity of purchased PCl5 from a closed down old lab).
My first project will be to make a solution of RuCl3 in water from my RuO2. If I look at the link at versuchschemie, then I have the impression that I
do not need to isolate the RuCl3 from the aqueous solution, I just need to concentrate the solution and then add the NaH2PO2 in order to reduce it to
ruthenium(II). More reading and studying will be required before I start experimenting with the RuO2.
|
|
|
woelen
Super Administrator
Posts: 8014
Registered: 20-8-2005
Location: Netherlands
Member Is Offline
Mood: interested
|
|
I think I have (somewhat impure?) Ru(bipy)2Cl2.
I proceeded as follows in a test tube experiment:
- Take a small spatula of RuO2 (I think 50 mg or so)
- Pour 3 ml of concentrated bleach on it (12.5% active chlorine). When this is done, then immediately, there is some fizzling, due to catalytic
decomposition of the bleach to NaCl and O2.
- Heat for several minutes to get all RuO2 dissolved. This gives a dark green solution of perruthenate, RuO4(-).
- Continue boiling for quite some time: The liquid turns red and there is production of small oxygen bubbles, the red color is due to ruthenate ion,
RuO4(2-). The bleach is converted to chlorate and chloride.
- Add an excess amount of 30% HCl. A lot of Cl2 and ClO2 is formed and a precipitate of NaCl is formed.
- Ignite the ClO2 in the test tube to have it decomposed in a controlled way (otherwise it may explode from the bottom).
- Decant the liquid from the solid NaCl and boil the liquid for a while to assure that all chlorate is destroyed and no Cl2 and/or ClO2 is formed
anymore. While doing so, the liquid turns dark brown.
- Add NaHCO3 until addition of the solid does not produce strong fizzling anymore. This makes the liquid near neutral. The color remains dark brown.
- Add an excess amount of bipy and a bigger spatula of NaH2PO2 and keep the liquid near boiling. When this is done, then the color slowly shifts from
brown to red. At a certain point the liquid is bright red and clear and does not change anymore. At that point I stopped heating. I think this was
between 10 and 15 minutes after I added the bipy and NaH2PO2 and started heating.
- Allow the liquid to cool down. This makes the liquid slightly turbid. One day later I had a layer of crystalline solid (glittering red pieces) and
an orange liquid above it.
The red material I have is not as bright as your beautiful orange/red solid. Right now I have it standing for another day and I hope to get a little
bit more of the red solid.
[Edited on 26-8-13 by woelen]
|
|
|
Pok
potassium Prometheus
Posts: 176
Registered: 5-12-2010
Member Is Offline
|
|
Interesting procedure. I thought that RuO2 would dissolve in HCl, but maybe it isn't that easy.
The only impurity I can imagine would be unconverted bipy. In a large scale this can be removed by washing with ice cold acetone (bipy is well soluble
whereas Ru(bipy)3Cl2 is not). But this will not influence chemiluminescence reactions, I think. Also, in large scale you can lower the solubility of
Ru(bipy)3Cl2 by adding KCl. The solubility of pure Ru-bipy in water is about 10 g/100 ml (very rough). Letting the solution cool to 0 °C will also
help to precipitate a little bit more.
One possible "bad" impurity would be unconverted NaH2PO2, because this influences oxidation/reduction processes directly. But due to it's good
solubility, there should be nothing remaining in the final (dried) product.
In my experiment the crystals of the product were very flat (like a sheet) and I think hexagonal.
[Edited on 26-8-2013 by Pok]
|
|
|
woelen
Super Administrator
Posts: 8014
Registered: 20-8-2005
Location: Netherlands
Member Is Offline
Mood: interested
|
|
I wanted to make KCl by adding KHCO3 instead of NaHCO3 to the strongly acidic solution (based on excess HCl), but I do not have KHCO3, hence the use
of NaHCO3. I can imagine that low solubility of Ru(bipy)2Cl2 does not depend on the presence of K(+) ions, but on the presence of high concentration
of Cl(-) ions.
RuO2 is rather inert, it does not react with HCl. You really need to heat the material with bleach and then slowly it dissolves. A lot of excess
bleach is needed, because the RuO2 catalytically decomposes bleach to oxygen and NaCl and because of the required heating a large part of the bleach
is converted to chlorate and chloride. It is not a convenient reaction at all, but I have no alternative for it. I also have Ru-metal (fine powder),
but with this it is the same. The only thing capable of dissolving the metal is concentrated hot bleach at sufficiently high pH.
[Edited on 26-8-13 by woelen]
|
|
|
Pok
potassium Prometheus
Posts: 176
Registered: 5-12-2010
Member Is Offline
|
|
| Quote: Originally posted by woelen | | I can imagine that low solubility of Ru(bipy)2Cl2 does not depend on the presence of K(+) ions, but on the presence of high concentration of Cl(-)
ions. |
Sure. I didn't read correctly. NaCl should do the same job.
| Quote: Originally posted by woelen | | I also have Ru-metal (fine powder), but with this it is the same. The only thing capable of dissolving the metal is concentrated hot bleach at
sufficiently high pH. |
I once dissolved Ru metal (powder) in a hot persulfate/hydroxide solution (as garage chemist mentioned in this or another forum). This works, too. I
also planned to make RuCl3 from Ru metal before I found a source for the salt. Afterwards, I stopped thinking about this approach.
BTW: the catalytic decomposition of bleach by RuO2 is quite interesting...
[Edited on 26-8-2013 by Pok]
|
|
|
woelen
Super Administrator
Posts: 8014
Registered: 20-8-2005
Location: Netherlands
Member Is Offline
Mood: interested
|
|
Nice to read about the persulfate/hydroxide method. I'll try that with my RuO2.
The catalytic decomposition of bleach by RuO2 is not that special. The same happens with cobalt. Just add a solution of any cobalt(II) salt to bleach
and the stuff nicely bubbles away, giving oxygen. The Co(2+) is oxidized to Co(3+) and this catalyses the decomposition of bleach.
|
|
|
woelen
Super Administrator
Posts: 8014
Registered: 20-8-2005
Location: Netherlands
Member Is Offline
Mood: interested
|
|
I did the chemiluminescence reaction and it works great.
I decanted the water from the test tube with the red crystal mass and rinsed two times with acetone. Only a small amount of the orange material
dissolved in the acetone. The rinse-liquid was yellow.
I allowed the material to dry (which only took a few tens of minutes) and took a small amount (a heap of maybe 3x3x3 cube millimeters. I added this to
water. Most of the material dissolved, but some red specks remained and dissolved with difficulty. The liquid is orange.
I added a fairly large amount of Na2S2O8 and dissolved this. The solid dissolves, but the liquid becomes strongly opalescent. It seems as if the
Ru-bipy complex does not really dissolve. The opaque liquid becomes orange/yellow.
Next, I added appr. half the volume of acetonitrile to the liquid and swirled. This makes the liquid perfectly clear. Also all little undissolved
specks are gone now.
Finally, I added a very small quantity of 5% HCl, hardly more than a single drop.
This liquid is my experimenting solution.
My first experiment is to take magnesium shavings and add these to the liquid. When this is done, then there is a brief flash of orange light (for
just a fraction of a second, like a LED which blinks one time) and then nothing happens anymore. The magnesium becomes shiny with a somewhat golden
color. No reaction occurs with this magnesium anymore, even when it is added to fresh liquid. If to the same liquid a fresh piece of magnesium is
added, then there is a brief flash of light and then it does not do anything anymore.
My second experiment is to clean the magnesium with some dilute HCl, rinse it again and add it to the liquid again. This again gives a brief flash of
light. To this liquid I added a full ml or so of 5% HCl and this results in strong fizzling and bubbling of the magnesium and a very strong orange
light which lasts for minutes! The effect is really amazing. The liquid becomes warm, but this is quite understandable, the heat is sinply produced by
the exothermic reaction between magnesium and dilute HCl.
So, the liquid really must be acidic for the light effect, the magnesium really must have the opporunity to react with the acid. The effect indeed is
very nice with magnesium pieces of the right size. My shavings are very coarse and too heavy, they remain at the bottom. I also did an experiment with
Mg-powder, but if that is done, then there is a nearly homogeneous emission of light from the liquid, which is bright, but only lasts for a short
time.
I have still some of the red solid left and can do more experiments with it. Time to take out the camera and see if I can make good pictures and a
movie.
[Edited on 27-8-13 by woelen]
|
|
|
Marvin
National Hazard
Posts: 995
Registered: 13-10-2002
Member Is Offline
Mood: No Mood
|
|
It sounds like the complex is not destroyed and might be recoverable afterwards. Would the acetonitrile survive an attempt to reoxidise?
|
|
|
Pok
potassium Prometheus
Posts: 176
Registered: 5-12-2010
Member Is Offline
|
|
Good work, woelen! I can confirm your observations with coarse and fine Mg used for the chemiluminescent reaction. I observed exactly the same: large
pieces don't glow a long time (and only if a large amount of acid is added) and fine powder will result in a homogenous glow without showing much of
the "thunderstorm effect". The key really is the right particle size but also acid concentration, I think.
@Marvin: I think the complex doesn't get destroyed in the reaction and could be recycled. The reaction mechanism is a cycle of reduction and oxidation
of this complex. At the oxidation step (according to the original paper) the complex gets activated and emits light. This cycle is driven by Mg metal
and persulfate. But I don't know how to isolate the complex out of the solution at the end of the reaction.
[Edited on 28-8-2013 by Pok]
|
|
|
woelen
Super Administrator
Posts: 8014
Registered: 20-8-2005
Location: Netherlands
Member Is Offline
Mood: interested
|
|
I did the reaction another time and now I made pictures and a video. The webpage is not ready yet, but here is a picture of the orange light:
A nice effect is the speck of magnesium, sticking to the glass, but not yet immersed in the liquid.
And here is a link to a video (size is appr. 8 MByte) with the same piece of magnesium, sticking to the glass.
http://www.homescience.net/chem/exps/Ru_bipy/orange_light.av...
The effect is clearly visible in a darkened room, but making a video of this is quite hard. For that purpose the effect is just a little too weak.
Hence the noisy video.
[Edited on 26-9-13 by woelen]
|
|
|
Pok
potassium Prometheus
Posts: 176
Registered: 5-12-2010
Member Is Offline
|
|
Nurdrage copied the idea and did this reaction here:
<embed
src="http://www.youtube.com/v/im_2OIs_mns?version=3&autoplay=0&showinfo=1&modestbranding=1&controls=1&theme=dark&vq=hd720&
hl=en_US&rel=0" type="application/x-shockwave-flash" width=640 height=360 allowscriptaccess="always" allowfullscreen="true"></embed>
I don't like the way he copies ideas and makes people believe that these are his own ideas. But at least the video gives some detailed information
about how to perform this reaction.
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
