Sciencemadness Discussion Board - Bismuth from its Subsalicylate (Pepto-Bismol®)

Bismuth from its Subsalicylate (Pepto-Bismol®)

Tacho - 13-2-2004 at 09:37

I would like to make a few grams of metallic bismuth.

Any chance I could get it from Pepto Bismol (bismuth subsalicylate)?

Any sugestions would be appreciated.

[<a href="u2u.php?action=send&username=bfesser">bfesser</a>: merged 4 threads; replaced subject of first thread, "Bismuth out of Pepto Bismol."]

[Edited on 8.8.13 by bfesser]

Organikum - 13-2-2004 at 12:38

I dont know how you can get it from Pepto Bismol, but I know that there are pellets for shotguns available which contain mostly bismuth. They are as replacement for lead-pellets for not contaminating the environment with lead. Dont get the steel-shot so....

Every better sorted hunters/weapon shop will have it or can order it. As it is thought to get mostly dispewrsed all over the earths surface there should be no problem at all to get it - cheap.

Friedrich Wöhler - 13-2-2004 at 12:51

Hi Tacho,

http://www.kremer-pigmente.de/pigmen13.htm#wismutmalerei

Its a German store for painting artists. ("Wismut" = Bismuth)

Well, Brazil is very far from here, but also there must be a source like this...

chemoleo - 13-2-2004 at 13:23

Besides, you can get bismuth from arts supplies (not pigment supplies such as kremer), it is sold pure in kg amounts, and sold as low melt alloys

[Edited on 13-2-2004 by chemoleo]

axehandle - 14-2-2004 at 00:50

Ah... yes! Now I also remember. Bismuth is indeed used as a replacement for lead shotgun pellets in countries where the politocrats haven't realized that lead in pure form is NOT an environmental hazard. I know of only one such place: the US of A. Here, the politocrats are making laws to replace the lead with iron. Idiots. A gun barrel wouldn't like that after a thousand shots.....

Edit: Try a local gun store that deals in equipment for hand loading.

[Edited on 2004-2-14 by axehandle]

rikkitikkitavi - 14-2-2004 at 04:45

some lead/tin alloys for soldering and making of tin-caracters (I dont know the exact word, but you know the small figures all boys used to make when 12) contains Bi for lowering the melting point. Shouldnt be to hard to separate them chemically.

/rickard

Electrolysis

hodges - 14-2-2004 at 05:13

If you really are intent on getting the bismuth from Pepto-Bismal, I would think electrolysis would do it. Sharpen both ends of two pencils. Connect the two pencils to a 6V lantern battery and dip the other ends in the Pepto-Bismal. Metal should form on the negative pencil lead.

Obviously, yields are not going to be too great, but if you just want to do it, it should work. I hear you can also prepare mercury from Mercurichrome (sp?) this way.

I am a fish - 14-2-2004 at 07:04

If you just want a small piece of bismuth, check out shops that sell rocks and fossils. They sometime sell bismuth crystals.

Geomancer - 14-2-2004 at 07:54

Axehandle: Please check your facts before insulting people. Detrimental effects from the use of lead shot are well documented. Lead poisoning kills about 2-3 percent of the US waterfowl population annually. Moreover, lead containing waterfowl present a hazard to anything that eats them. Problems arising from sublethal doses have not been so well examined but undoubtedly exist. IIRC some indications are present of acccumulation in fish of lead from elemental sources, but I'm not sure of the details.
As regards your gun barrels, only the ignorant would let hard shot contact them in the first place. Use a shot cup.

Mr. Wizard - 15-2-2004 at 01:32

Bismuth shot is a rather scarce item. I bought a box of shells from Cabela's and emptied out the shot. It is rather pricey. I was going to try some of the diamagnetic levitation tricks.

Thank you all!

Tacho - 15-2-2004 at 01:45

I'm pretty sure I'll get some elemental bismuth soon using all these tips!

Hodges, to get it from pepto bimol, yours was a very good Idea. I just found out that adding some HCl to the thick pepto bismol emultion turns it into a clear colorless solution, ready to electrolisys. Ill try this Idea first. I was thinking of reduction with carbon at high temperatures, but that would be messy and, maybe, useless.

If my math is right, there is 5,7g of bismuth to every 10g of dry, pure subsalicylate.

Reagent grade elemental bismuth cost the equivalent of about 50 euros for 100g around here!

I want it because I'm curious about it's unique magnetic properties. It is reppelled by magnets.

Theoretic - 15-2-2004 at 07:01

Heating it strongly should work. Organic heavy-metal salts decompose to the carbonate and then the carbonate decomposes to the oxide. The carbon that is made during the decomposition should then reduce the oxide, however I think there's going to be an excess of C, so the resulting metal isn't going to be very pure.

unionised - 15-2-2004 at 16:22

IIRC you can reduce bismuth (III) compounds with tin(II) in alkaline solution.

Tacho - 20-2-2004 at 02:59

If you basify the pepto bismol and dilute it 1:2 in water, the bismuth salt sediments.
If you acidify and pass through a sieve the sedimented salt, dilute in water, you end up with an almost clear solution.
I found out by accident that if you put a thick aluminum foil in this clear solution, dark gray powder precipitates from the foil.
A-ha! A reduction of bismuth by aluminum! Al reduction potential= -1,66, Bi red. pot.= -0,46 , 0,32 or 1,8. Well, I don’t know why Bi has 3 different potentials but they are all bigger than –1,66, so reduction by Al foil makes sense I guess... The only table I could find that had Bi in it is very confusing.

Well, then things started going wrong! I washed, filtered and dried this precipitate, but when I tried to melt it down, it didn’t. It smoked and glowed as if it were burning. Remained a black (not yellow as oxide and hydroxide should be) oxide-like thing, about 1cc of it. I tried to flux it with borax, but made things worse.

I would appreciate comments about this, specially opinions about if that precipitated could really be bismuth and, if so, what flux can I use to melt it to a nice shiny blob.

Metallic bismuth from diarrhea medicine

kaviaari - 23-12-2006 at 01:08

This process might be quite well known.

I found out that certain diarrhea medicine contains over 0.5g of bismuth subsalicylate per pill. Every pack has the total of ten pills in it. First of all I thought that if I would like to take bismuth out as a metal I had to figure out how to dissolve it. First I tried 2M hydrochloric acid. The piece off pill only formed a white precipitate. I thought that if the bismuth subsalicylate had broken down to ions I could reduce the metal out with zinc. I took a piece of zinc sheet and dropped it into the tube. Hydrogen was formed but I didn't recieve the black bismuth precipitate. Ok, so I had to make a bismuth compound that dissolves easily to acid. It took a while, but then I came up with heat. If the salicylate could be turned to oxide. I went outside and heated the pills in a crucible. Some smoke came off and after few minutes I could clearly see some yellow spots of bismuth oxide. I turned off the heat and dosed few millilteres of 1M hydrochloric acid in a test tube. I poured the yellow-black-brown stuff from cucible among the acid. The tube was shaken and then left alone in hot water bath for few minutes. The organic stuff didn't dissolve so I filterated the solution in another tube. When I added the piece of zinc in I saw the most beautiful sight. The heavy bismuth was precipipating and falling at the very bottom of the tube. When all of the bismuth had reduced I filterated it.

The product is quite crude and one can see some impurities on it. Any ideas for purification? It would be neat to melt it and have those beautiful bismuth crystals.

[Edited on 23-12-2006 by kaviaari]

crude_bi.jpg - 29kB

unionised - 23-12-2006 at 03:02

Nice experiment.
I don't know how experienced you are in this sort of thing so I'm hesitant to say this but I have reduced bismuth from the oxide using charcoal with sodium hydroxide as a flux. Obviously the molten sodium hydoxide is very nasty stuff. It eats glass so I used an tin can as a cheap "crucible".
If you are sure you know what you are doing then this might be a suitable way to clean up the stuff you have. The NaOH will dissolve any zinc compounds. (I'm away visiting my family over Xmas and the new year so I won't be able to offer any advice until I get back.)
I wonder if anyone else has any experience with this sort of thing.

kaviaari - 23-12-2006 at 03:13

That sounds very good. I'll convert all of my pills to oxide and then give it a try. I'll report the results as soon as I can.

[Edited on 23-12-2006 by kaviaari]

[Edited on 23-12-2006 by kaviaari]

JohnWW - 23-12-2006 at 03:20

With such a supply of Bi-209, if you can then get your hands on some Ra-226 and Be-9 and intimately mix them to result in a neutron source, you can then make your own Po-210. You could then use this to poison any ex-KGB agents whom you dislike, or anyone else with whom you disagree.

unionised - 23-12-2006 at 03:27

If you had that big a Ra226 source you could use it to poison people with rather than mess about making Polonium. Also, the neutron capture cross section of Bi is pretty small so you would need a serious neutron source. If you were going to embark on this pointless exercise then it would probably not be worth converting the Bi to the metal first.

Speaking of not converting it first, I think that heating the bi subsalicylate with excess NaOH would probably work anyway. The organic bits would act as a reducing agent. Just be very wary of the molten alkali and, of course, do it outside unles you have a propper fume hood.
(What's the weather like in Finland?)

kaviaari - 23-12-2006 at 05:46

I am quite familiar with molten alkalies (I made sodium by electrolysis a while ago) and I have red bromicacids experinments too

. It's not snowing or raining here in Finland (nor is here any snow) so I suppose that I can easily do the experiment outside. Of course a fume hood would be very nice

. Problem is with the outlet. And when living with parents one can't just drill a hole in the wall. My lab is also getting too small in every possible way. Chemicals and glassware are eating up space and I have no idea where I am going to place the rotary vaporator that I'm going to recieve after new year.

[Edited on 23-12-2006 by kaviaari]

unionised - 23-12-2006 at 06:06

"And when living with parents one can't just drill a hole in the wall. My lab is also getting too small in every possible way."
I know what you mean, I live alone and have my own house. I still don't have enough space.

(BTW, at the risk of sounding very English and talking about the weather, would you normally expect to have snow by late December. We have had a remarkably warm Autumn/ Winter so far and I wonder how widespread it is.

kaviaari - 23-12-2006 at 06:38

Quote:

True. In normal winters we would have snow by late December, and to speak truly so did we have this time too. It snowed a lot, I mean a lot in just few days and after that it all melted away. From there we haven't had much snow.

Shall we blame the global warming?

woelen - 23-12-2006 at 07:56

We also have a remarkably warm autumn and winter. Over here in the Netherlands, we had more than 20 C in October, and up to now, we didn't have a single day of frosty weather!

But back on topic, I have some basic bismuth nitrate. I did some experiments with reducing that, but it seems it does not work. The basic nitrate needs a strongly acidic environment to keep the bismuth dissolved and under those conditions, the metal seems not to precipitate (too much nitrate in it?).

UnintentionalChaos - 23-12-2006 at 18:08

It's depressingly warm here in the Northeastern US. It's warm enough to be outside without any jacket (although I wear tee-shirts year round anyway). It was freezing cold for most of october and part of november, but It's quite warm now. At least I can do some of my experiments outside later than I thought I would

I'm with you Kaviaari and Unionized. I've consumed my father's workbench in the garage (not that he uses it too often anyway) and have absolutely no way to vent fumes. I have to go outside for that kind of thing.

I think I may have some of those pills around so I may have to try this...now for my minor acid problem, and by minor, I mean extremely irritating. I'd just distill HCl drain cleaner but I don't have anywhere near the proper setup. I'd end up eating a hole in something.

mericad193724 - 23-12-2006 at 19:12

Guys,

I am pretty sure there is an easier way to extract metallic bismuth from diarrhea medicine...the liquid type(Pepto-Bismol and friends). I have a book at home that describes this exact experiment in which you add freshly prepared sodium stannate solution to the pepto-bismol and you get a fine black suspension of bismuth in the syrup. If diluted with water and filtered, bismuth powder can be obtained. It’s a high school chem. demonstration/lab from a teacher's book.

I am not at home right now so I can't recall the experiment very well. Maybe you can find it on the web somewhere, good luck!

Happy Holidays

Mericad

phangue - 27-12-2006 at 18:19

Check a large farm-supply store in your area for gallon-size jugs of bismuth-type preparations.

NeutralIon - 28-12-2006 at 13:53

Why go to so much trouble to get Bi? Just get some Bi fishing sinkers [sold as an environmental friendly alternative to Pb]. I got some 3/4 oz [about 20 gms] for $1 each.

guy - 28-12-2006 at 13:54

Quote:

Originally posted by NeutralIon
Why go to so much trouble to get Bi? Just get some Bi fishing sinkers [sold as an environmental friendly alternative to Pb]. I got some 3/4 oz [about 20 gms] for $1 each.

Where do you find those...I can never find them in wal mart of sports stores.

kaviaari - 28-12-2006 at 13:59

Quote:

Just for the fun of it

. I wanted to try out if I can do it. If I would need large ammounts of bismuth for some experiment it would of course be more reasonable to buy it then.

[Edited on 28-12-2006 by kaviaari]

Waffles - 28-12-2006 at 16:33

Quote:

Bismuth is basically the only non-toxic heavy metal (relatively 'non-toxic,' everything is toxic in sufficient doses). Therefore, any bismuth extracted from drug-grade chemicals, such as those used in the medicines we are discussing, is likely to be extremely pure- the purity is most dependent on your method of reduction, likely, but theoretically it should be very very pure and free of any other heavy metal.
On the opposite end of the spectrum, bismuth sinkers and bismuth shotgun shot are meant to be CHEAP alternatives to lead. Even the brands that say "pure" or whatever, I wouldn't trust to be any purer than 97 or 98 percent, very optimistically. For making bismuth crystals especially, you need purity several factors of ten greater than this.

Summary: For 'quick and dirty' preparations, you could indeed go the sinker/ammo route, but that is certainly not the be-all, end-all of OTC bismuth.
Also, buying a pound of bismuth at a time from United Nuclear or various eBay sources is cheaper than your sinkers, and >99.99% purity rather than 97%

...

neutrino - 29-12-2006 at 02:00

To illustrate this point, I bought several pounds of 99.99% Bi off eBay not too long ago for $8.50 / lb. That's a lot cheaper than those $1 / 20g sinkers. :cool:

Obtain bismuth from the subsalicylate?

Gobstopper - 8-3-2009 at 04:27

What would be the best way to obtain elemental bismuth from bismuth subsalicylate? I know that bismuth chloride and other simpler salts can be electrolyzed to yield the element but would that work with this compound?

Paddywhacker - 8-3-2009 at 05:22

According to Wiki, it is not an ionic compound.
Therefore it would not be easy to electrolyze.

But you should be able to extract the bismuth into hydrochloric acid if you shake it up with dilute HCl and an organic solvent such as hexane, ether, chloroform, etc.

The bismuth will go into the water phase as the chloride, which you can electrolyze, and the salicylic acid will go into the organic phase.

That is ... according to theory.

As for the electrolysis ... look up Bismuth's position on the electrolytic series. Maybe you can displace it from solution with zinc or magnesium. Thats gotta be easier than electrolysis.

GoatRider - 8-3-2009 at 06:37

Bismuth is pretty cheap on United Nuclear. Extracting it from pepto bismol seems like an expensive way of going about it.

Gobstopper - 8-3-2009 at 15:53

Alright, well GoatRider I know that I can just order it from unitednuclear but that would defeat the purpose of my weekend project (one of em anyways)

Paddywhacker it appears that you are right about the electrolysis - the pink liquid does not conduct electricity. I tried an electrolysis last night by adding saltwater to the mix but I didn't see any evidence that this would send electrical current through any of the bismuth subsalicylate.

I'll try using HCl and a nonpolar organic solvent - unfortunately at the moment I don't have any nonpolar solvent so I'll probably have to synth up some chloroform

(or buy hexane/ether somewhere)

kclo4 - 8-3-2009 at 16:07

Why couldn't you just dissolve the subsalicylate in HCl and then perform electrolysis on that? I don't think salicylic acid would react with the bismuth very fast. Alternative why not just add Al foil, or Zinc powder to reduce the chloride to bismuth?

Gobstopper - 8-3-2009 at 16:29

Alright thanks kclo4 I'll give that a shot

Gobstopper - 8-3-2009 at 16:44

K so I added some HCl to the pink mixture and relatively quickly the solution lost most of its pinkish color so there is obviously a reaction that has taken place. The mixture is much easier to send an electric current through it and surely if I were to electrolyze it, elemental bismuth would result. However that will have to be done later.

For now I'll take 1/2 of it and put it in a container with pieces of aluminum foil (I like the zinc powder idea better but I don't have any atm) and see if any notable traces of bismuth evolve. Will keep posted

Interestingly, there is quite a bit of bismuth contained within pepto-bismol. 30ml of liquid contains more than a gram of the stuff.

kclo4 - 8-3-2009 at 17:10

Make sure there isn't a significant excess of HCl otherwise it might take a while for the Al to start producing Bismuth.
Also don't let it get to hot - Aluminum chloride is a Lewis acid and will hydrolyze into its hydroxide and HCl. If HCl reacts with bismuth in solution, the bismuth will redissolve.

I'm excited to see how this turns out, Its been something I've been wanting to do but haven't got the motivation to do it.

Gobstopper - 8-3-2009 at 17:51

After a little while of letting the reaction take place, a white emulsion appeared surrounding the aluminum foil pieces. Not long after, a whitish powder which isn't very soluble in the mixture (consisting of HCl, water and pepto :p) is seen floating around.

I might have added too much HCl though so we'll see. it's not hard for me to redo this experiment if I mess it up lol

kclo4 - 8-3-2009 at 18:01

I see. Well I'd guess the white stuff is aluminium hydroxide or something like that.
Hmm might it also be salicylic acid? I know that isn't very soluble in water so perhaps if it cooled off, it may have precipitated. I don't know.

Gobstopper - 8-3-2009 at 18:17

That would seem to make sense, if the reaction is going as planned then salicylic acid would indeed precipitate, and since it is pretty much insoluble in water, it fits.

I can't yet tell if any bismuth metal is in there as of yet as it's kinda hard to see through all that but it seems like if things are going the way they seem to be, there should be the metal in there.

not_important - 9-3-2009 at 06:46

I did this once, just for fun when a local store's closing resulted in some extreme markdown on a bismuth salicylate product (yes, it's bismuth subsalicylate but the main label doesn't state it that way)

First I added enough saturated NaHCO3 solution to be in excess of all the subsalicylate and salicylic acid in the product, then gently boiled it for some minutes. Decant/filter off the sodium salicylate solution, treat the precipitate with strong HCl to dissolve the bismuth away from the silicates used for product appearance reasons. I then reprecipitated the bismuth with NaHCO3 (I had a 25 kilo sack ot it), washed, dried, and reduced the ppt with carbon. You could try reducing the HCl solution with excess Al or Fe.

Gobstopper - 9-3-2009 at 15:08

K so after the filtration, a white solid appeared on the top of the filter paper while the liquid (which is clear but acidic from the HCl) went through. I'm almost sure that the solid is a salicylate but unfortunately I don't see much sign of the bismuth.

I'm going to try and basify the liquid which went through but think I'm going to have to wind up redoing this experiment, which is no big deal. I think I used too much HCl versus not enough Al, so this time around I'll limit the HCl and adding more Al, and also I'll start by basifying it (something I should've thought to do originally but didn't for some reason :p)

"I didn't fail - I just learned 9,000 ways not to make a light bulb" - Thomas Edison

[Edited on 9-3-2009 by Gobstopper]

kclo4 - 9-3-2009 at 15:51

If you over base, you can precipitate a carbonate, or a hydroxide.
This might be a way to go about it.. I think you may be able to form an oxalate and then decompose that. Some of the nonreactive metal oxalates decompose leaving the metal in its pure state. Another possibility to get the metal may be to reduce the oxides with hydrogen. The oxides could probably be produced by heating the carbonate or hydroxide to decomposition.

Tacho - 9-3-2009 at 16:20

I remember at least two other threads here about obtaining bismuth from peptobismol. I failed in my crude attempt. I remember someone succeeded using HCl and some reduction, like not_important mentioned.

Magpie - 10-3-2009 at 13:31

For the qualitative analysis of Bi+++, it is first precipitated as Bi(OH)3, a white ppt, using ammonium hydroxide. This is then reduced immediately to fine black elemental bismuth by addition of freshly made sodium stannite solution. However, I think it would be more satisfying to do the reduction with carbon as indicated by not_important.

DJF90 - 2-11-2012 at 05:17

Found this whilst browsing online, figured it might be of use to some here: http://www.popsci.com/diy/gallery/2012-07/gallery-extracting...

triplepoint - 2-11-2012 at 05:47

Quote: Originally posted by DJF90

Found this whilst browsing online, figured it might be of use to some here: http://www.popsci.com/diy/gallery/2012-07/gallery-extracting...

Thanks djf90. Those instructions make it look easy. I already have a pound of bi, but I'm going to have to try this synthesis as a point of non-professional pride

Random - 2-11-2012 at 10:04

I think I saw extraction of bismuth, you can just heat bismuth salilicylate until it decomposes to metal

oh yeah here is the video

http://www.youtube.com/watch?v=Hp1fYtYEfoQ

[Edited on 2-11-2012 by Random]

Lead-free fishing tackle

arsphenamine - 3-11-2012 at 08:58

If you simply want bismuth, scout out lead-free sinkers.

Some are technical bismuth. Others are alloyed with tin and/or antimony.

Wizzard - 3-11-2012 at 09:05

Ah, I logged in just to say you can isolate it with a blowtorch. So much for that!

Bismuth (trioxide?) from Pepto Bismol

MrHomeScientist - 23-6-2013 at 14:20

I'm sure most people have heard of the process to isolate bismuth metal from Pepto Bismol - if not, here's TheChemLife's video on it.

I tried it out this weekend. I wanted to take the black powder at the end and melt it down into a lump of metal. Every time I heat the powder, though, it turns yellow instead! I'm thinking this must be bismuth(III) oxide. I tried redissolving this yellow powder in HCl, reprecipitating with aluminum, and heating again (this time with better rinsing of the precipitate); the same yellow powder resulted.

Looking at Theodore Gray's pictures of his preparation, he did exactly the same thing I am doing but obtained shiny metal at the end. Any ideas as to why mine would oxidize instead of melting? What needs to be done to get a solid piece of bismuth metal from this?

platedish29 - 23-6-2013 at 16:06

Mr., particulate lead shows the same results. The problem is the lead powder is so horryfingly powdered is oxidizes in the presence of air!!
Or perhaps you just bought some head-glue placebos due to similar problems I had when extracting silver from x-ray plates.

12AX7 - 23-6-2013 at 17:12

Try a cover flux. Regular soldering flux should do the trick (usually a combination of pine rosins, petroleum jelly or mineral oil, and zinc chloride for the acid varieties), though even mineral oil would help in a pinch. Make sure it's dry, and for that matter, make sure it dries out without oxidizing too much -- perhaps starting with the moist cake, wash it with acetone (to remove water), then toluene (to remove acetone, and to get a lipophilic liquid phase), then disperse it in mineral oil. If it stays floating in the oil even at melting point, try draining (or boiling or burning!) some off and adding some rosin. Just be careful, of course, that if you burn some off, that soot doesn't get inside and make things harder.

Tim

violet sin - 23-6-2013 at 17:40

what about borax for flux? works for a lot of things and readily available.

12AX7 - 23-6-2013 at 17:42

Good stuff, but too high an activation temperature. Barely molten by aluminum temperatures (not that it does any good on aluminum!), but excellent for copper and friends.

Tim

Hexavalent - 24-6-2013 at 12:01

What about just heating over a gentle stream of argon or nitrogen?

Godspeed429 - 24-6-2013 at 17:34

Maybe you got it too hot when you tried to melt it.
In the comments section of TheChemlife's video he says
" i have tried to melt it down but bismuth is a testy metal. to hot and it turns into the oxide instead of melting so all i have left is yellow bismuth oxide."
Maybe the same thing happened to you.

12AX7 - 24-6-2013 at 19:11

Quote: Originally posted by Hexavalent

What about just heating over a gentle stream of argon or nitrogen?

Well la-de-da, why don't we just vacuum purge it in an induction furnace too?

Tim

watson.fawkes - 24-6-2013 at 21:01

Quote: Originally posted by 12AX7

Well la-de-da, why don't we just vacuum purge it in an induction furnace too?

Because what this problem really needs is an e-beam melter to get fine control over the melt zone.

Why stop at 5 figure equipment when 7 figure equipment will do?

blogfast25 - 25-6-2013 at 04:09

Just a heavy duty flux should work wonders here.

Poppy - 25-6-2013 at 10:58

If bismuth shouldn't form metallic alloys with zinc, why not then use zinc as a tapper?
As what I've seen lead forms alloys with zinc but at solidifying temperatures the zinc will precipitate up on top, that might just save your samples!

12AX7 - 25-6-2013 at 18:49

Indeed, the phase diagram shows no solid solubility (or very little at least -- under 1%), and little miscibility in the liquids. Note, however, that any Zn crystallizing in the Bi solution won't magically float out, it will remain as a slush (much as NaCl isn't 100% soluble in water and forms a slush when supersaturated), which you'd have to filter somehow.

ZnCl2 should be a fine flux also (a primary ingredient in 'acid' soldering flux).

Tim

Godspeed429 - 4-7-2013 at 06:32

I did this same experiment over the past weekend, and i was able to obtain a small amount of the elusive bismuth. when i applied heat the black powder it turn yellow like yours. so i continued to heat in til it glowed red and was partially liquified. After heating and cooling a few times i noticed what looked like air bubbles forming in the molten liquid, turns out this is the bismuth. i was only able to obtain .7 grams of bismuth out of my 7.2 gram "slug". i can still see more bismuth precipitating out of the slug when i heat it but it is in very small portions and i don't know how to separate it out.

I did the experiment with 60 pills. My yield should of been greater than 7.2 grams but it was dropped once before weighing.

MrHomeScientist - 20-8-2013 at 12:54

Quote: Originally posted by 12AX7

Try a cover flux. Regular soldering flux should do the trick (usually a combination of pine rosins, petroleum jelly or mineral oil, and zinc chloride for the acid varieties), though even mineral oil would help in a pinch.

Well mineral oil is a bust - it boils at far too low of a temperature. I placed my Bi powder in a crucible, covered it with the oil, and started heating. Within 30 seconds the oil started to boil. I kept heating it, to make sure it wasn't dissolved water - it's definitely the oil boiling. Sort of obvious in retrospect...

So next attempt will use zinc chloride. It melts at a higher temperature than bismuth, so I would need to melt it first and then add the bismuth powder. Perhaps melt the salt in one crucible first, and pour this on top of the bismuth in another crucible? This would avoid the powder sitting on top of the molten salt and remaining exposed to the air.

Extracting Bismuth From Pepto-Bismol

nelsonB - 1-10-2013 at 21:44

Hi
for those who is looking for Bismuth
here a good protocol i have found

http://www.popsci.com/diy/gallery/2012-07/gallery-extracting...

elementcollector1 - 1-10-2013 at 22:43

Quote: Originally posted by nelsonB

Hi
for those who is looking for Bismuth
here a good protocol i have found

http://www.popsci.com/diy/gallery/2012-07/gallery-extracting...

I believe this has been discussed ad nauseum on this board already...

bismuthate - 2-10-2013 at 03:09

I don;t want to be an ass but UTFSE
http://www.sciencemadness.org/talk/viewthread.php?tid=1527&a...
This has a link to a video insid the thread..
(I isolated some bismuth last week)

Metallic bismuth from Pepto-Bismol

Griffin K - 2-3-2014 at 10:24

Hello! A while back I extracted some elemental bismuth from Pepto-Bismol using the hydrochloric acid and aluminum foil method. I ended up with a black powder, and since then I've been attempting to melt it down to obtain a blob of the actual metal, without success. On my first attempt I used a propane torch to heat it in a crucible, and it quickly oxidized to a yellowish bismuth(III) oxide. I next tried heating the bismuth on a stove, and depending on the temperature, I either got more oxidation or nothing at all. I think there's a very narrow temperature window between the melting point and the oxidation temperature, and I'm not sure how to get it. I have seen a few accounts of people successfully melting it down, so I know it is possible, but I'm not sure what I can do. Has anyone else successfully done this? Or might a bismuth oxide thermite be a better method? Thank you!

Metacelsus - 2-3-2014 at 10:35

Both MrHomeScientist and I ran into this problem. Neither of us was able to get an ingot. You could try reducing with carbon (carbothermic reduction). A thermite would be messy.

blogfast25 - 2-3-2014 at 12:36

Because the BP of bismuth (1564 C) is well below the MP of alumina (2072 C) aluminothermy ('thermite') isn't going to work here, or only with very low yields.

Prolonged heating (around 1000 C or higher) of a mixture of bismuth trioxide and an excess of fine carbon should work but it would takes time, depending largely on temperature...