Sciencemadness Discussion Board - Preparation of elemental phosphorus

Preparation of elemental phosphorus

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barley81 - 1-7-2011 at 09:01

Yeah! But it must have been a lot of trouble to stand the smell, so it's equally difficult

bbartlog - 1-7-2011 at 15:45

I don't know as most of us necessarily have better equipment than Brandt... he probably had a pretty decent iron retort and lots of fuel. Also, he didn't cook 'his own piss', he had multiple thousands of liters from the people of whatever town he was working in (as I recall).

blogfast25 - 2-7-2011 at 04:40

It’s only funny if you look at it superficially, less so IMO if you know the story better.

Brand spent large amounts of money on scientific pursuits, without much success, throughout his life, gradually getting his family into debt.

With his ‘urine cooking experiment’ he was actually trying to make gold, which at the time was believed by some to be contained in urine (hence the colour!). Hence the concentrating of much piss, and the subsequent attempt at reducing the ‘piss concentrate’. The look on his face when he didn’t produce gold but obtained the first man made phosphorescing material ever, must have been priceless.

Brand later spent much of his life trying to sell his method (he kept the details secret for quite some time) for making phosphorus to leading scientific figures of his time but only succeeded a few times.

The reason why most of us here only manage to make small amounts is mainly: resources. Brand’s furnace, also going by the picture below, was likely to be quite large and charcoal fired (= very hot):

http://www.google.co.uk/imgres?imgurl=http://www.bpc.edu/mat...

[Edited on 2-7-2011 by blogfast25]

peach - 26-7-2011 at 04:01

Quote:

With his ‘urine cooking experiment’ he was actually trying to make gold, which at the time was believed by some to be contained in urine (hence the colour!)

blogfast25 - 26-7-2011 at 05:06

Very funny. I thought I had seen all of Blackadder but I don't recall the 'green' discovery!

Rogeryermaw - 2-8-2011 at 17:10

sooooooo. i had a go at turning some of my caucasian phosphorus into native american phosphorus. it seems that it is not too hard. i placed about 2 grams into this vial and put it in the sun where it would not be disturbed.

i have noted some properties that may or may not be of interest. the P4 undergoes change rather quickly but surface area is quite key. it is quite warm here (around 38-40 celsius) and so, of course, the P4 liquefies in the vial since it is against a surface that gets a good deal warmer than this. this is not so odd but the phosphorus exhibits the properties of a supercooled liquid in that it will not solidify until it has been cooled significantly and agitated.

there also seems to be some level of sublimation. as you can see from the photo, the entire inside of the tube is coated with a deposit of red P.

as far as surface area, this is difficult to control with a liquid in such a small, closed container and extensive handling of the starting material is arguably dangerous. i have scraped the sides of the vial when i bring it inside at night and by the end of the following day, i find the vial coated again with the red deposit. much repeating of this will eventually convert most of the material but a larger vessel, allowing more contact to more of the product by solar radiation will undoubtedly push the conversion along faster. just wanted to share what i have been up to lately. i will get back to work on the mixed amine synthesis very soon.

Endimion17 - 7-8-2011 at 09:36

This is a bit offtopic, because it's not a preparation from a compound per se, but the thread on micropreparation is not so appropriate, and opening a new thread has no point.

I wanted to make a sample of white phosphorus for my element collection, so I started doing some small scale distillations from red allotrope in various self-made glass retorts, just to see what can go wrong before I try to do it on a larger scale. By larger, I mean in larger glass tubing.
My best advice to anyone trying to do this is - do not try it using flasks. Do it in disposable glass apparatus made out of glass tubing (not less than 4 mm in diameter).

I find that designs like this one:

are the best, and if you make several such small retorts, you can make a reasonably large amount of the substance in less than half of an interesting afternoon. If someone wants me to explain the flameworking part, let me know.
I loaded the tube with the red P before finishing the last narrow part.

The retort is meant to be held in hand, using wooden tongs or similar tool. The globules of the molten phosphorus collect in the first horizontal part, and when they become larger than 2-3 mm, you incline the apparatus and they slide in the lower part. There absolutely has to be a vent at the end, and the lower part must be wide enough so the phosphorus won't make a plug. If it does, either the reaction vessel will burst (and then you're in danger) or there'll be some fireworks at the vent tip, which are benign if the vent is pointed away from you. Either way, this means you have to wear protective equipment.
I've tried to distill it directly in cold water, but sooner or later, either water or air will find their way into the hot retort. P will catch fire, or the retort will crack, and I'll leave to your imagination what can come out of that situation. It is possible, it is quick, but it's also nerve wrecking, because you hold the retort in one hand and cold water in another.

The key is to heat the red P as less as possible, because the more you heat it, the less nice and transparent globules you get.
Patience is needed to collect very pure white P, because extra heat turns makes it orange. I've managed to make nearly pure transparent P, but I smashed the retort to see it glow.

Start with very small amounts, few matchhead-sized pieces at first, and practice manipulating and ampouling the phosphorus. You can make the first matches and smash them outside during the night.

After the proper distillation, you'll get lots of solid blobs which can be joined together by gently heating the water over 45 °C. Never remove the phosphorus from warm water, even if it's solid. It's seconds away from catching fire.

Used retorts contain some white P, so be sure to destroy them appropriately as they're are a fire hazard.

One cool thing is that white P, or at least the impure one I got seems to be capable of undercooling. It will stay molten under water at room temperature until you touch it with a glass rod.
This transparent yellow sample (not under water, just ampouled) is still molten, and it's around 28 °C in my room.

The glow is just beautiful.

Unfortunately, I don't have the equipment to take a nice long exposure macro shot.
It's eerie, like a liquid light with a greenish tinge that flutters lightly when you try to blow it. The less orange the P is, the more it glows. The piece was increasing its glow, so I returned it to water immediately.

[Edited on 7-8-2011 by Endimion17]

[Edited on 7-8-2011 by Endimion17]

ScienceHideout - 7-8-2011 at 18:25

It seems we all ignored one thing... An experiment I did earlier was very effective. It was not to produce phosphorus, but it inspired me to think of this:

No one mentioned acid catalyzation. Am I ignoring something? Am I forgetting that all phosphates blow up in acids? What if we can somehow use acids to react all the compounds necessary and eliminate the need for distillation, furnaces, etc? Could we use... say... acid catalysation along with reflux?

What if we take some TSP, add it to an RBF along with carbon and sand, pour in some water and acid, reflux, and call it a day (after we get phosphorus!)?

Just an idea. Don't crucify me if I am ignoring something...

EDIT: BTW good job to the previous poster on the glow in the dark ampoule worthy desk nicknack

!!

[Edited on 8-8-2011 by ScienceHideout]

Rogeryermaw - 7-8-2011 at 23:37

i am pretty certain that this method, along with electrolyzing phosphate solutions and reduction of phosphoric acid in a microwave have all been discussed in depth in this thread. if, however, you want to give it a go, i am sure there would be many parties interested in your results. just be sure whatever you use, that any phosphorus produced will not react with the chemicals used. it is quite reactive.

@ Endimion17, woelen has the most fantastic site with some killer projects he has performed and outlined in great detail with pictures and even some videos. he has one that is similar to the distillation you performed. you should have a look <a href="http://woelen.homescience.net/science/chem/exps/RedP2WhiteP/index.html" onclick="window.open(this.href); return false;">here</a>. have a run through the rest of his site as well. it is truly amazing.

good work on the WP. i noted the supercooling properties as well. that makes WP even more dangerous than anyone first thought as some of us have observed that phosphorus in liquid form at any temp will ignite instantly when exposed to oxygen. as a solid i have noticed it is tame until oxidation raises its surface temp to the melting point.

[Edited on 8-8-2011 by Rogeryermaw]

Endimion17 - 8-8-2011 at 03:48

@ScienceHideout: Your idea reminds me of experiments like making potassium "the other way around". You should check the enthalpies etc., and do lots of microscale experiments. There's no definitive answer to your question, and if you find a forgotten/unknown way of producing P, you could patent it, and if it's efficient, earn some money. Of course, you understand there's a very small chance for that.
There's a god reason why factories make P using lots of energy, and it's not someone's wish. If they knew a more efficient process (and there are scientists working on it) they'd use it sooner or later.

@Rogeryermaw: I know about his site, it's truly a great one, but I don't like the vessel he used for phosphorus. If I recall correctly, it was a poorly bent test tube in which large amount of WP was collected. Those things have a tendency to crack if they weren't annealed, and you really don't want that, as it will lead to a spitting inferno. "May lead" and other legal minced oath BS is not appropriate language here.
And the whole idea of working underwater, cracking the tube, filtering and manipulating this hideously poisonous pyrophoric substance is not something which makes me happy, as I don't really like heavy protection equipment and really like my precious liver.

This apparatus

when small enough, can be safe if one knows how to handle it. My vessel was <1cm in diameter. Spherical blobs of WP form while falling trough the upper tube, and the widened part can be useful for enhanced cooling and avoiding a quick sucking back of the water. That problem is actually rather avoided by making a proper retort with a small reaction vessel, relative to its neck, which avoids the thermometer-like behaviour.

Once you start the process, you should finish it.
During the first few minutes, vapors (WP, pentoxide) and some small bits of WP will exit the tube and self ignite in air after bubbling through the water. They produce popping sounds, like hydrogen in a test tube. It's annoying and somewhat scary, but benign (small scale!).
Also, the pentoxide vapors will try to "suck" the water in, so be careful not to stop heating at that moment.

Regarding the heating source, it might be possible to do this with a candle. That's how energy intensive this is.
It's best to heat the tip of the vessel, to avoid passive heating of the neck as much as possible.
And if you make several small retorts, the danger is very small, and you get the joy of distilling red P several times.

It's elegant, fun and requires small energy input. And you can make almost transparent and white WP if you're careful not to overheat, and to cool the blobs immediately upon forming.

The liquid WP in my ampoule stayed liquid untill night, when I started messing with it. It touched a rough point and turned solid. I estimate the speed was around 2 m/s, as I saw the wave of solidification. It gave small amounts of heat at that point.

[Edited on 8-8-2011 by Endimion17]

ScienceHideout - 8-8-2011 at 04:53

Thanks for your reply. I will definately try some microscale... but I think everything would be better if we all just distilled 60 buckets of pee with some sand and carbon.

Rogeryermaw - 8-8-2011 at 10:41

brandt's experiment would be much more productive if one skipped the whole putrefied urine step and just ordered some microcosmic salt. it's quite cheap. i think the toxicity of WP is serious, but it does not scare me. its pyrophoric properties are much scarier to me, having been burned by it before. the wounds heal slowly and are excruciatingly painful.

woelen's bent test tube is a bit crude and there is room for improvement, but the ingenuity he shows is inspirational. as for me, i doubt i will ever distill red phosphorus. it is too simple for me to run the furnace, which, of course, is done outdoors. i made quite a bit of WP last year and still have enough that any runs in the future are solely meant to streamline the process and try to improve yields.

ScienceHideout - 8-8-2011 at 17:50

What about those aqua globe retorts shown to youtube by chemical myst?

Bot0nist - 8-8-2011 at 18:32

Here is the link to the video he refers to. <a href="http://www.youtube.com/watch?v=hDpVEX5SZzg">myst32YT's 10 useful tips.</a>

It's a great video, and a good channel.

Endimion17 - 9-8-2011 at 14:43

Here, proof I've made some really white P.
It's very hard, but it's possible.

Those are fresh blobs together with the piece I've shown earlier.

Only the first few fresh droplets are white, after that, they're getting yellow, then orange. Temperature of the retort is not relevant, I've checked that by halting the process for a few minutes.
It's like something happens in the red P. Maybe some kind of reaction between nonvolatile residues in it, or between fresh WP and red one, I don't know.
In order to get lots of really white WP, one would need to slowly heat lots of pure red P and immediately cool the vapors. Afterwards, yellow version distills.
Impurities in the retort shift it towards orange.

Endimion17 - 18-8-2011 at 05:15

Is this the first photo on teh internets of glowing WP? :cool:

Man, it's hard to take those photos with a crappy camera, though I've enjoyed the supermacro option.
I've tried to do it with a small blob, but it caught fire after it melted. I've got it all on video, which was pure luck as the thing allows only 10s videos at a time. Weird glowing and then wham, fire, right in third second. Stay tuned, there'll be an update at this channel.

The worst part is when you have to set the camera, and the thing just partially melts. You try to pick it up to put in in the water, but it's stuck to the paper, and behaves like tree resin in the summer. You throw the bigger piece in the water, and the leftover sits there stucked, seconds away from bursting into flames. :mad:

Damitwhy - 18-8-2011 at 16:05

I've been very interested in building a furnace and "do it the old-fashioned way" myself but I realize it would be so much easier, less time consuming and more manageable if I were to use an "Induction Heater Coil" as the heating source with a Steel or Iron Retort.

This link shows a home made induction heater coil heating metals to red/whiteness with in seconds :

http://www.youtube.com/watch?v=LT5VvBQfOoo&feature=relat...

Costs for purchasing some thing like this would be in the thousands but this other link shows affordable home build:

http://www.richieburnett.co.uk/indheat.html

I've got less money than sense but would love to give this a go... if any one else gets there before me please give feed back and tell me how you got on

Attachment: Phosphorus.pdf (527kB)
This file has been downloaded 708 times

blogfast25 - 19-8-2011 at 07:29

I'm kind of surprised no one has brought up induction coils in this context before. It's not without its own problems of course but it's definitely a '21st Century approach'. Nice work if you can get it and don't get shocked!

Damitwhy - 19-8-2011 at 09:19

Wow its not as costly or even much hassle when an induction hob can be purchased for less than £50... Stumbled across this induction hob and realized its potential not only for the phosphorus furness (with modification) but in reflux heating if ceramic coated iron pellets were used as boiling chips...

http://www.mirrorreaderoffers.co.uk/item-pp-d3197/induction-...

With a little modification and reverse engineering items like this could be in most hobby chemist work places

Wizzard - 19-8-2011 at 10:39

Those only work well for large pans with thinly clad layers of copper- For lab use we'd need something with a very different induction value (and much higher frequency).

Phosphorus sesquisulfide

vr6t4dr - 23-8-2011 at 16:39

so, is there any way to use Phosphorus sesquisulfide?

Damitwhy - 25-8-2011 at 14:34

Quote: Originally posted by vr6t4dr

so, is there any way to use Phosphorus sesquisulfide?

I'm not sure, I've not found anything via google searches but I'm pretty sure that if you were working with a pure dry sample of Phosphorus Sesquisulfide you could still make the reagent Phosphorus Trichloride (PCL3) with Sulphur Dichloride as a side product by direct Freeradical Chlorination in Dichloromethane (DCM)...

this great youtube link will explain how just by substituting pure Sulphur for Phosphorus Sesquisulfide... Not completely sure though so Dont Do This without doing your own research into this reaction..!

http://www.youtube.com/watch?v=HTzUhLuYlHU&list=FLLQ41kT...

I suppose this post was pretty unrelated but I thought it would be interesting just jumping straight in with a reagent most people would need pure Phosphorus for...

1911 - 1-9-2011 at 22:05

There was somewhere in this thread a mention that elemental phosphorus can be made by reacting phosphine with copper(II)chloride (solution) in following reaction: 4 PH3 + 6 CuCl2 --> P4 + 6 Cu + 12 HCl. This could be a superior method over the retort method as it could be done using glass apparatus. Am I now over looking something why this wouldn't work of why this method hasn't been discussed before?

Rogeryermaw - 2-9-2011 at 14:06

Quote: Originally posted by 1911

There was somewhere in this thread a mention that elemental phosphorus can be made by reacting phosphine with copper(II)chloride (solution) in following reaction: 4 PH3 + 6 CuCl2 --> P4 + 6 Cu + 12 HCl. This could be a superior method over the retort method as it could be done using glass apparatus. Am I now over looking something why this wouldn't work of why this method hasn't been discussed before?

likely due in large part to the extreme toxicity of phosphine. it is a gas at s.t.p. which makes it difficult to handle for the average home experimenter. as part of the process i have used to synthesize white phosphorus from 6(Na(PO3) it is generated in small quantities with diphosphine which causes it to ignite instantly on contact with oxygen.

do not forget that metal phosphides are used as powerful rodentacides in farming applications. metal phosphide is reacted with water to produce phosphine gas which is quite deadly.

blogfast25 - 3-9-2011 at 11:53

Quote: Originally posted by 1911

Am I now over looking something why this wouldn't work of why this method hasn't been discussed before?

Phosphine toxicity. As mentioned by Roger. Don't go there as a hobbyist...

Endimion17 - 4-9-2011 at 03:43

I'd be more afraid of its pyrophoric properties than toxicity. You can always vent the gas. But that stuff, when impure (and it usually is) ignites in contact with air and could explode.
I presume not many of you here has Schlenk lines with argon...

Rogeryermaw - 5-9-2011 at 12:36

phosphine is actually produced in relatively high purity from the action of moisture on aluminum phosphide. it is used in large scale pest control operations such as in barns and grain silos. its toxicity, however, is a danger, even to innocent bystanders.

<a href="http://www.ksl.com/index.php?hl=2&sid=9615227" onclick="window.open(this.href); return false;">this link has an example of the extreme danger of exposure to PH3.</a>

i will definitely not understate the flammability danger of phosphine though as i have seen how quickly it can burn and a large amount of it would be able to cause an explosion worse than a natural gas leak.

blogfast pretty much hit the nail on the proverbial head with his warning that it is a substance best left to the professional.

edit: the article needs some fact checking. at one point, they wrote that it was aluminum phosphate in the ground and then aluminum phosphine. no odd occurrence that the writer did not know the correct names of these substances though. in the amateur chemist community, this fact is shoved in our faces on a daily basis.

[Edited on 5-9-2011 by Rogeryermaw]

blogfast25 - 7-9-2011 at 04:47

Very tragic, that incident (your link).

I’d be jittery if a pest control company started messing with phosphide containing tablets around my house. The tablets are supposed to be ‘slow release’ but the technical people who deploy them tend to know diddly squat about chemistry and phosphine. Incorrect, nonchalant or over-zealous application of the product is seriously dangerous.

Acc. Wiki the flammability of phophine is actually associated with diphosphine (P2H4) which nearly always accompanies PH3 generated from phosphides.

Rogeryermaw - 7-9-2011 at 14:25

after further investigation, i must apologize for my misunderstanding. you are correct, of course. i knew that the diphosphine was the major contributor in the spontaneous ignition. this left me wondering how phosphides were used as a fumigant. it seems that impurities are used to cause the "doping" of the phosphine. other chemicals are used with the phosphide that cause it to evolve gasses other than just phosphine and diphosphine to dilute the gas to a concentration that will not ignite.

still, given incidents like the one i referenced, it should be obvious that even a small leak in the apparatus used to control such gasses could be catastrophic. these tablets were used outdoors and underground and still let enough fumes into the home to cause a death and health problems for the rest of the family. truly sinister compound.

"chemical" phosphorus

pip - 21-9-2011 at 08:54

There was some talk on the use of acids to reduce phosphates on the last page. I don't know anything about that but if cost isn't an issue rp can be made in a beaker. The method is posted somewhere in this thread towards the begining I think.

lialh4, carbitol, triphenyl phos???

[Edited on 21-9-2011 by pip]

SNiko9 - 22-9-2011 at 06:47

Quote: Originally posted by peach

aax
Registered: 23-9-2010 <------------------ Yesterday
Posts: 5

Search
Preparation of elemental phosphorus
Preparation of elemental phosphorus
Preparation of elemental phosphorus
Preparation of elemental phosphorus
Preparation of elemental phosphorus

Hello. how can i see this video?

Chemistry Alchemist - 22-9-2011 at 06:59

Quote: Originally posted by SNiko9

Hello. how can i see this video?

Ive got a video on preparing WP, it isnt the BEST video out there but it does show how to make a small amount of it, there are other ways to get better yields

http://www.youtube.com/watch?v=Q2YrGvuygKU

[Edited on 22-9-2011 by Chemistry Alchemist]

SNiko9 - 22-9-2011 at 07:14

Quote: Originally posted by Chemistry Alchemist

Quote: Originally posted by SNiko9

Hello. how can i see this video?

you are right about this video. Have you got another one? may be video to praperate P4 from this reaction 6 NaPO3 + 15 Al = 6 NaAlO3 + Al5P3 + 2 Al2O3 + 3 P

Chemistry Alchemist - 22-9-2011 at 07:24

Quote: Originally posted by SNiko9

you are right about this video. Have you got another one? may be video to praperate P4 from this reaction 6 NaPO3 + 15 Al = 6 NaAlO3 + Al5P3 + 2 Al2O3 + 3 P

How would one come across NaPO3 or make NaPO3, that sounds like a really easy and viable way to getting Phosphorus

blogfast25 - 22-9-2011 at 08:42

Quote: Originally posted by Chemistry Alchemist

How would one come across NaPO3 or make NaPO3, that sounds like a really easy and viable way to getting Phosphorus

Some types of Calgon tablets contain it.

It can also be made by heating (modestly) ammonium dihydrogenphosphate (found in crystal growing kits) with sodium chloride (table salt):

NH4H2PO4 + NaCl === > NaPO3 + NH4Cl + H2O

The water and ammonium chloride evaporate off, leaving behind a hard mass of NaPO3. It's described a few pages higher up.

But making sizeable amounts of P4 safely is not easy at all. READ this THREAD!

Chemistry Alchemist - 22-9-2011 at 08:55

On a wiki page it says you can make it from Disodium phosphate, how would you do this? ive looked around on alot of sites and came across nothing.

ive been reading the whole post, pretty good methods have been discussed, and yeah, ive read alot of information about P4, i know its unsafe

not_important - 22-9-2011 at 15:38

NaNH4HPO4 AKA Microcosmic Salt is old school, there's plenty of detailed preps out on the Net, many in old chemistry books for example a not very detailed one

Quote:

Microcosmic salt (sodio ammonium phosphate) may be prepared
by dissolving together 6 parts of sodium phosphate and 1 part of
ammonium chloride in 2 parts of water and allowing to crystallise.
The salt should be purified by re-crystallisation j when heated ou
wire or charcoal it froths, loses ammonia and leaves a clear bead of
sodium mctaphosphate which possesses the property of dissolving
many metallic oxides with their characteristic colours.

fromhttp://www.archive.org/details/cihm_01142

Chemistry Alchemist - 22-9-2011 at 17:40

would this work the same way as ammonium dihydrogenphosphate in the reaction blogfast25 suggested?

Rogeryermaw - 22-9-2011 at 18:24

if you are referring to the videos i made they are on you tube here:

<a href="http://www.youtube.com/watch?v=mibM4WUx74Q" onclick="window.open(this.href); return false;">vid 1</a>
<a href="http://www.youtube.com/watch?v=4YjUC2dmNV0" onclick="window.open(this.href); return false;">vid 2</a>
<a href="http://www.youtube.com/watch?v=23bXKpLyXJk" onclick="window.open(this.href); return false;">vid 3</a>

sodium hexametaphosphate 6(NaPO3

is available as water softener from fabric and dyeing supply. finely powdered reactants work best and be sure to dry everything in the oven prior to starting the reaction to reduce the amount of phosphine PH3 produced.

edit:
after a couple of tests i have concluded that the use of NaCl in the mixture, while helping to increase yield by acting as a flux or viscosity reducer, may lead to a slightly less pure product (possibly to the presence of chloride ions as some of the sodium is bound with the sodium from the metaphosphate. still working on this one). you may omit this and will still yield phosphorus. my first several runs were done this way.

[Edited on 23-9-2011 by Rogeryermaw]

Remarkable Chemistry of Elemental Phosphorous

AndersHoveland - 17-10-2011 at 23:42

Elemental phosphorous can apparently be dissolved in liquid sulfur dichloride without reaction. Phophorous can be stored under water, but when finely divided it decomposes water producing hydrogen phosphide. When boiled with water, phosphine and hypophosphorous acid are produced.

Various Hydrides of Phosphorous

P2H4, first obtained by P. Thenard (Comptes rendus, 1844, 18, p. 652) by decomposing calcium phosphide with warm water, the products of reaction being then passed through a U tube surrounded by a freezing mixture (see also L. Gattermann, Ber., 1890, 23, p. 1174). It is a colourless liquid which boils at 57°-58° C. It is insoluble in water, but soluble in alcohol and ether. It is very unstable, being readily decomposed by heat or light. By passing the products of the decomposition of calcium phosphide with water over granular calcium chloride, the P2H4 gives a new hydride, P12H6 and phosphine, the former being an odourless, canary-yellow, amorphous powder. When heated in a vacuum it evolves phosphine, and leaves an orange-red residue of a second new hydride, P9H2 (A. Stock, W. Bottcher, and W. Lenger, Ber., 9 9, 4 39, 47, 2853).

P4H2, first obtained by Le Verrier, is formed by the action of phosphorus trichloride on gaseous phosphine (Besson, Comptes rendus, 111, p. 972); by the action of water on phosphorus di-iodide and by the decomposition of calcium phosphide with hot concentrated hydrochloric acid. It is a yellow solid, which is insoluble in water. It burns when heated to about 200° C. When warmed with alcoholic potash it yields gaseous phosphine, hydrogen and a hypophosphite.

shannon dove - 30-11-2011 at 05:48

What about dissolving tricalcium phosphate in dilute hydrochloric acid, then spraying it in a very fine mist into an electric arc in a reducing gas such as hydrogen?
When the spray gets into the arc , fine particles of calcium phosphate will form, and these will be reduced by the hydrogen into calcium phosphide then that will make hydrogen phosphide, the hydrogen phosphide will decompose from the heat and precipitate phosphorus particles.

shannon dove - 30-11-2011 at 06:13

Let me explain this idea better.
Electrodes for the arc are put inside a jar. The jar is purged with hydrogen, a very fine mist of a dissolved phosphate is sprayed into the arc. After a while the jar will have some phosphine gas, this phosphine will pass through the arc and be broken into phosphorus and hydrogen, the light coming from the arc will make the phosphorus turn into the red form. These particles of red phosphorus will fall to the bottom inert to the other chemicals in jar.

blogfast25 - 30-11-2011 at 12:22

shannon dove:

Hydrogen cannot reduce phosphates or P2O5, not by a long shot.

Your idea cannot work, period.

AndersHoveland - 30-11-2011 at 15:09

Quote: Originally posted by shannon dove

Let me explain this idea better.
Electrodes for the arc are put inside a jar. The jar is purged with hydrogen, a very fine mist of a dissolved phosphate is sprayed into the arc. After a while the jar will have some phosphine gas, this phosphine will pass through the arc and be broken into phosphorus and hydrogen, the light coming from the arc will make the phosphorus turn into the red form. These particles of red phosphorus will fall to the bottom inert to the other chemicals in jar.

I think this idea would probably work, just my opinion.
For example, hydrogen chloride can be oxidized by oxygen to chlorine in the presence of electric discharge.

Quote:

A gaseous mixture of hydrogen chloride and oxygen, in proportion of 4 volumes of HCl and 1 volume of O, was enclosed in a tube, and submitted to the action of the electric spark for some hours; nine-tenths of the mixture was decomposed, with the formation of free chlorine and water.

Inversely, a weighed quantity of water, enclosed with free chlorine, was decomposed in a similar arrangement to the extent of one-tenth of the oxygen being being liberated.

The former reaction takes place easily, when the mixed gases are passed through a red-hot porelain tube, and the latter reaction, as is well known, occurs by itself at the ordinary temperature, especially in the presence of sunlight.

Reciprocal Displacements between Oxygen, Sulfur, and the Halogens, when combined with Hydrogen.
by Berthelot
Scientific American: Supplement, Volume 7, No. 175, p297

shannon dove - 30-11-2011 at 15:32

Propane or methane could be used instead of hydrogen. The intense heat of the arc would decompose the methane and make some carbon simuler to charcoal, and we know charcoal will reduce phosphates at arc temperature.

AndersHoveland - 30-11-2011 at 15:53

Aqueous alkali (KOH) dissolves red phopshorous, with the formation of phosphine. Interestingly, when hydrochloric acid was added to the solution, the phosphorous precipitated back into its elemental form.
Journal of the Chemical Society, Volume 75 (Great Britain) p.976

In this respect, the chemistry of phosphorous would appear similar to several other elements (such as sulfur and the halogens) in that the presence of a base causes the element to disproportionate, while re-acidification shifts the equilibrium back to favor the elemental form.

I have also found two sources that suggest that water slowly reacts with finely divided phosphorous, forming phosphine and some form of phosphorous acid in a lower oxidation state, although it is not clear whether this is a one-way reaction, or whether it is an equilibrium. I strongly suspect the latter.

[Edited on 30-11-2011 by AndersHoveland]

blogfast25 - 1-12-2011 at 08:33

Quote: Originally posted by AndersHoveland

I think this idea would probably work, just my opinion.
For example, hydrogen chloride can be oxidized by oxygen to chlorine in the presence of electric discharge.

Forget it.

PH3 + 3/2 O2 === > P + 3/2 H2O ???

The P will be oxidised immediately to P2O5: 2 PH3 + 4 O2 === > P2O5 + 3 H2O

It works with HCl because chlorine has little tendency to combine with oxygen, phosphorus however combines readily with most elements that are more electronegative than itself.

Not to mention that you’d have to reduce P2O5/phosphate to phosphine first, with hydrogen. Impossible.

shannon dove - 1-12-2011 at 15:58

The jar would would not have any free oxygen in it to oxidize any phosphine produced. Any oxygen produced by the arc would be immedietly combined with the hydhrogen or carbon of the methane. You say hydrogen will not reduce phosphates, what about the carbon in methane?
My idea is to have a system that starts out with about an inch of water and dissolved phosphates in the jar. A small pump draws this up and sprays it into the arc, then the water and phosphate falls back to the bottom and the cycle repeats.
I want this to run automaticly, just set it up and it runs a few hours. I am trying to make this like the arc method of making nitric acid (birkland eyed).
An arc seems to work well for reactions that require a very high temperature.
I say use a mist and a gas because it is easier to control than putting solids into an arc, wich is the industrial method.

shannon dove - 1-12-2011 at 17:02

Let me explain further.
Everytime I put some solids between electrodes, like powdered charccoal, sand and bone ash, then I turn on the arc, something is always not right. The distance is too much, its not enough, the material is not a the right spot. If it starts working good it will only work for a few seconds then it has to be moved again. It cannot just be settup to run like the arc method of making nitric acid, that can run for days.
Therefore it is very easy to understand that a method to make phosphorus that involves puting gases into an arc might be worth researching.

shannon dove - 3-12-2011 at 11:04

I am thinking about buying an ultra sonic humidifier. They put out a very fine mist, and unlike other humidifiers the minerals in the water go into the mist. Minerals like phosphates maybe.

Panache - 5-12-2011 at 18:38

what happens when all your water has turned to steam?

shannon dove - 6-12-2011 at 05:43

The ultra fine mist would come down from the top of the jar and pass through the arc then it would condense on the bottom of the jar , and be pumped back to the mister and cycle again.
For the phosphate liquid-mist, what about water soluble phosphate dissolved in water and alchohol mixture. At arc temperature the carbon in the ethanal will combine with the oxygen in the phosphate. I know at arc temps the ethanal will not be ethanal anymore, but whatever organic compounds are formed , the carbon should still be able to reduce phosphates and form carbon monoxide. I think at arc temps the e

shannon dove - 6-12-2011 at 06:21

At arc temps the alcahol will form lampblack type carbon and free hydrogen and the oxygen atom in alcahol will just unite with the hydrogen, maybe some acetalyne will be formed (charcoal and hydrogen react in an arc to form acetalyne).
In this closed system there will be a whole lot of unreacted alcahol and I think there might form some very complicated organic phosphorus compounds, but these should break down in the arc and make phosphine, and I think from phosphine we could easily get phosphorus.

bahamuth - 6-12-2011 at 08:18

Quote: Originally posted by blogfast25

shannon dove:

Hydrogen cannot reduce phosphates or P2O5, not by a long shot.

Your idea cannot work, period.

It appears that hydrogen can in fact reduce phosphates: http://pubs.acs.org/doi/abs/10.1021/cm970175g

And I quote -Several transition-metal phosphates, arsenates, and antimonates undergo direct reduction in hydrogen at relatively low temperatures (400−1050 °C) to the corresponding phosphides, arsenides, and antimonides....., and -We could not however synthesize pnictides of manganese, vanadium, and gallium by this route, suggesting that the method is applicable only to those metals that are less electropositive than hydrogen, that is, those metals whose binary oxides are reducible by hydrogen to the metallic state.

ScienceSquirrel - 6-12-2011 at 08:45

Quote: Originally posted by shannon dove

At arc temps the alcahol will form lampblack type carbon and free hydrogen and the oxygen atom in alcahol will just unite with the hydrogen, maybe some acetalyne will be formed (charcoal and hydrogen react in an arc to form acetalyne).
In this closed system there will be a whole lot of unreacted alcahol and I think there might form some very complicated organic phosphorus compounds, but these should break down in the arc and make phosphine, and I think from phosphine we could easily get phosphorus.

This sounds like a novel way to have a nasty and to an observer at a safe distance interesting accident.

shannon dove - 6-12-2011 at 11:19

iron oxide is reduced to metal by hydrogen, so iron phosphate should be reduced to iron phosphide by hydrogen. What if we dissolve tricalcium phosphate in hydrochloric acid, then add iron chloride to precipitate iron phosphate, heat iron phosphate to dull red in hydrogen to get iron phosphide, react this phosphide with hydrochloric acid to make phosphine. I think iron phosphide reacts very slowly with acids , so it should be ground to a fine powder first.
I know, I know, something simular to this has already been talked about on this thread, but there was not much talk about the best way to make iron phosphide and more important the temperature needed.

blogfast25 - 6-12-2011 at 12:59

Quote: Originally posted by bahamuth

It appears that hydrogen can in fact reduce phosphates: http://pubs.acs.org/doi/abs/10.1021/cm970175g

Your link and quote say nothing about how this is achieved.

Quote: Originally posted by shannon dove

iron oxide is reduced to metal by hydrogen, so iron phosphate should be reduced to iron phosphide by hydrogen.

And you conclude this, how???

For instance, iron (III) phosphate’s structure is that of ferric ions, Fe3+ and phosphate ions, PO43-, joined in an ionic lattice. Reduction with hydrogen here is very similar to reducing P2O5 with hydrogen and that cannot be done because P2O5 has far too high a heat of formation.

In bahamuth’s linked paper undoubtedly forcing conditions are applied to reduce D-block phosphates to phosphides.

shannon dove - 6-12-2011 at 14:12

Aluminum oxide , silicon dioxide and calcium oxide all have very very high heat of formation, but from the books I have read, under certain conditions, all can be reduced by carbon in an electric furnace. I know that early attemps to do this with calcium only made calcium carbide, but I have also read that it has been done.

blogfast25 - 6-12-2011 at 14:42

Quote: Originally posted by shannon dove

Aluminum oxide , silicon dioxide and calcium oxide all have very very high heat of formation, but from the books I have read, under certain conditions, all can be reduced by carbon in an electric furnace. I know that early attemps to do this with calcium only made calcium carbide, but I have also read that it has been done.

These are reduced because one of the gaseous reaction products (CO or CO2) is removed from the mix, that pushes the equilibrium to the right. using hydrogen that's not possible because it is a gas itself. In the case of Calcium, that too can be distilled off.

You're flogging a dead horse here...

shannon dove - 6-12-2011 at 14:50

Forget I said anything about hydrogen, maybe I am wrong, thats why I ask people on here, to see if my ideas sound possible before I waste a lot of time and money on an impossible project. I will give up on reducing phosphates with hydrogen.
Anyway, I have been searching for hours on methods of making iron phosphide. I have been searching patents. Does this sound possible, I drop a spoonfull of iron phosphide powder into a jar half filled with acid, a tube made into the top tranfers the phosphine to a pipe heated to about 600 celcius, the phosphine deposits phosphorus.

blogfast25 - 7-12-2011 at 09:03

Quote: Originally posted by shannon dove

Does this sound possible, I drop a spoonfull of iron phosphide powder into a jar half filled with acid, a tube made into the top tranfers the phosphine to a pipe heated to about 600 celcius, the phosphine deposits phosphorus.

Phosphine(s) are very dangerous: highly flammable and highly toxic. Really not something you want to mess with in appreciable quantities in a makeshift home lab.

Producing phosphorus in home lab attainable conditions isn’t really that hard. But capturing the formed P is harder, as this whole thread testifies to. For home chemists the reaction of sodium metaphosphate with aluminium powder and silica remains the most viable option.

shannon dove - 8-12-2011 at 06:18

This is just my opinion, please do not get mad.
Using aluminium for any home chemical project is cheating ! Aluminium is more difficult to make than phosphorus. Using aluminium to make phosphorus is like buying red phosphorus then turning it into white phosphorus and bragging that you made white phosphorus. Its like getting someone else to make you some concentrated nitric acid and glycerin, then bragging that you made nitroglycerine.
If you use aluminium, the aluminium factory has done three/quarters of the work for you. Any post that talks about using aluminium, I do not even read it.

blogfast25 - 8-12-2011 at 06:34

Home chemistry is about using what you can get your hands on. If you call that 'cheating' you're unlikely to ever make anything at home, unless you're a well equipped near-genius with far too much time on his hands.

If I read you correctly, for instance someone using zinc/carbon battery fill to extract MnSO4 would be cheating because he's using existing batteries and didn't go and mine some sulphur and turn it into sulphuric acid? Or extract his own oxalic acid from rhubarb?

What you say is absurd!

ScienceSquirrel - 8-12-2011 at 06:47

Quote: Originally posted by shannon dove

Forget I said anything about hydrogen, maybe I am wrong, thats why I ask people on here, to see if my ideas sound possible before I waste a lot of time and money on an impossible project. I will give up on reducing phosphates with hydrogen.
Anyway, I have been searching for hours on methods of making iron phosphide. I have been searching patents. Does this sound possible, I drop a spoonfull of iron phosphide powder into a jar half filled with acid, a tube made into the top tranfers the phosphine to a pipe heated to about 600 celcius, the phosphine deposits phosphorus.

It sounds like an excellent way of making a a sizable explosion that will spray you with glass, acid and toxic shit.
Most lab chemistry, even real professional labs, uses methods and reagents that are different to industrial methods and use premade reagents a lot of the time.
Aluminium is cheaply and readily available compared to phosphorous as far as home chemists are concerned so it is a viable reagent for them.

shannon dove - 8-12-2011 at 07:05

But you could make sulphuric acid at home if you had to, but aluminium on the other hand would be a hundred times more difficult.
I am just saying I would feel a lot more of an accomplishment if I did not use a ready made off the shelf very strong reducer like aluminium. Aluminium will pull the oxygen out of anything!! (almost).

blogfast25 - 8-12-2011 at 07:41

Quote: Originally posted by shannon dove

Aluminium will pull the oxygen out of anything!! (almost).

Yes but it turns out that recovering the reduced phosphorus really is the hard part at home level!

shannon dove - 8-12-2011 at 08:12

Ok, those are all good points.
I have been thinking about doing the well tested method of reducing phosphates with aluminium.
I will still look for other methods too.

ScienceSquirrel - 8-12-2011 at 08:42

Quote: Originally posted by blogfast25

Quote: Originally posted by shannon dove

Aluminium will pull the oxygen out of anything!! (almost).

Yes but it turns out that recovering the reduced phosphorus really is the hard part at home level!

Together with not setting fire to or poisoning yourself with the bastard stuff.

neptunium - 12-12-2011 at 11:16

yes please let us know how it works out for you i am dying to find out!
i want to use sodium tri phosphate from home depot . dehydrate the stp in the oven before mixing with sillica and active carbon all of the above in a small steel tube , the latest in the grill with air blowing on the hot charcoal....should be enough heat....hopefully .
a copper tube is leading the gasses in a cold bucket of water...

my concern ( other than not getting phosphorus) is the presence of sulfates in the original stp...?
the box doesnt give any info ..
any thought?

shannon dove - 12-12-2011 at 15:16

You said trisodium phosphate, silica and charcoal; what about aluminum powder?
Read the rest of this thread. It seems that aluminium works at a lower temp, so its better for backyard chemist.
It will be a while before I try it, I still have to make a propane torch or furnace.
I am thinking air blast from leaf blower plus propane.

shannon dove - 12-12-2011 at 15:34

I realy realy realy wish that charcoal woul work instead of aluminium!!!
Just like I realy wish that dilute nitric acid would nitrate stuff !!!
The many challenges of chemistry.

blogfast25 - 13-12-2011 at 05:56

Quote: Originally posted by neptunium

dehydrate the stp in the oven before mixing with sillica and active carbon all of the above in a small steel tube , the latest in the grill with air blowing on the hot charcoal....should be enough heat....?

The heat you need to carry this off with carbon will soften your steel.

Use hexasodiummetaphosphate ((NaPO3)6, HSMP) and aluminium powder (and silica) instead. Read the thread for sources of HSMP. And check out the safety precautions: phosphorus is a dangerous substance!!!

[Edited on 13-12-2011 by blogfast25]

neptunium - 13-12-2011 at 06:53

i was just thinking of activated carbon because thats what i have right here but aluminum powder is a VERY usefull reducing agent indeed and if order some i will absolutlytry it !!
I used to collect samples of each elements and had played with both red and white phosphorus back when it didnt raised any flags (thank you DHS and DEA)....ha that takes me back !....good times!
Also i wanted to continuously flush the tube with a low flow of argon ,to prevent any suck back of water ... i dont really want to open a hot steel tube full of hot white P!

neptunium - 13-12-2011 at 07:00

Use hexasodiummetaphosphate ((NaPO3)6, HSMP)...good idea! melting point 550C...most of the one i've found contain sodium carbonate though

blogfast25 - 13-12-2011 at 10:03

Quote: Originally posted by neptunium

Use hexasodiummetaphosphate ((NaPO3)6, HSMP)...good idea! melting point 550C...most of the one i've found contain sodium carbonate though

A bit of carbonate won't hurt here.

neptunium - 23-12-2011 at 06:56

what does that have to do with anything??? i hate commercials...

Sedit - 1-1-2012 at 18:08

Has anyone ever experimented with fusing Hexasodium metaphosphate with Sodium acetate? I did a little while ago just messing around and the mixture liquified rather quickly and a strong smell of garlic was released. It seemed like the NaOAc was acting as a rather good carbon source and a flux because once the melt was fluid there was a large release of Phosphorus at a pace much faster the I have seen in the past using a number of the following.....powdered carbon, powdered Aluminum, Magnesium(the most potential IMO) I can't help but wounder if Sodium acetate could become very helpful in creating White phosphorus.

What is every ones thoughts on such an idea?

Magpie - 1-1-2012 at 18:39

That's an interesting observation. I suppose you're speculating the following:

2NaC2H3O2 + heat ----> Na2O +3H2O + 2C

Did you see any evidence of water vapor or condensation?

Na2O would indeed be a good flux, and the C is then available for reduction of the metaphosphate to P.

What kind of vessel did you use for the experiment? How hot do you think it was when it liquified?

I wonder what would happen if you added a stoichiometric amount of SiO2.

BTW I have never smelled garlic when making P. I hope that is because I had good containment within my apparatus. And/or a good fume hood.

entropy51 - 1-1-2012 at 18:48

Quote: Originally posted by Magpie

BTW I have never smelled garlic when making P. I hope that is because I had good containment within my apparatus. And/or a good fume hood.

Magpie, in my opinion you have the best fume hood owned by any of us on Science Madness. My hood works just fine, but yours puts mine to shame!

Sedit - 1-1-2012 at 20:48

It was just a small open Stainless steel cup, I have a bunch of them for doing little melt test and what not. I just got propane for my torch for the first time in a couple months so of course I was playing around

.

I didn't even put to much thought into what it taking place reaction wise I just noticed that where normally I will get a bubble pop here or there using most other reducing materials this was more like a fine sheet of tiny bubbles glowing on the surface of the melt. It was just a crude experiment and run on a very small scale but I figured I would report what I seen here and let you all make your own conclusions about it. I have an IR thermometer so I will repeat it and test the temperature.

At first I seen water vapor but that was just because my NaOAc was not totally dry. Im going to run out and check the temperature, BRB.

Sedit - 1-1-2012 at 21:18

Ok so testing it with the IR isn't exactly easy on such a small scale but I will give you the numbers I got. Keep in mind these are rough estimates but there was some stability in them.

At around 375 degrees C I started to smell garlic, There was some sputtering as waters seemed to leave and the NaOAc carbonized. The temperature kept rising to about 490 degrees C at which point the reaction became very fluid, once total fluidity was achieved is when the temperature quickly dropped down to around 380 and remained rather stable as many many small bubbles popped on the surface of Phosphorus. Also there did not appear to be much carbon at the time the temperature dropped and the majority of the Phosphorus seemed to be produced. I don't know what to make of it but given the crappy setup it might just be superficial and mean nothing.

I wish I could give you more data but my setup leaves alot to be desired and I was just toying around at first. I can't go much further with any experiments until I make a better setup to avoid poisoning myself with Phosphorus. Hope this helps folks.

Conclusion?

alphacheese - 30-1-2012 at 22:15

Wow that's a lot posts. It took me all night to get to the end of page 2. I'm very familiar with bone ash, sand, and coke but was there a common consensus of a method that doesn't take white heat to evolve P4?

And just in case anyone was interested this Handbook of Chemical Technology by Johannes Rudolf Wagner has industrial methods for P4 synthesis from bone ash starting on page 537.

[Edited on 31-1-2012 by alphacheese]

jgourlay - 31-1-2012 at 06:23

"This is just my opinion, please do not get mad.
Using aluminium for any home chemical project is cheating ! Aluminium is more difficult to make than phosphorus. Using aluminium to make phosphorus is like buying red phosphorus then turning it into white phosphorus and bragging that you made white phosphorus. Its like getting someone else to make you some concentrated nitric acid and glycerin, then bragging that you made nitroglycerine.
If you use aluminium, the aluminium factory has done three/quarters of the work for you. Any post that talks about using aluminium, I do not even read it."

I don't know why you would hold this opinion. Everyone here has a different level of competency and so what is cheating for you may be a very high bar for others.

In your example above about nitroglycerine, let's take your reasoning to it's absurd logical conclusion. That is, YOU can make nitro by "not cheating" because you are so godlike in your capacities that you can drill your own oil, build your own refinery in the back yard, crack that oil, collect the sulphur waste, make your own h2so4.

At which point you amble out to the pile of cow manure you've been lovingly stacking up for the last year and start boiling that down to collect the potassium nitrate you'll use to make your nitric acid. In your spare time you'll be fabricating your own glassware/reaction vessels.

Once all that's done (whew!) you'll go out to the pasture, shear your sheep, wash the wool, and collect the glyceriney goo for purification. THEN you're off to make your nitro.

Anything less, dear, and you will be cheating.....

To the point of this thread: smelting of bauxite is simple, easy, and straightforward. It's EXPENSIVE to do in the back yard both because of the quality of refractories necessary and because of the wattage consumed. But it is a btdt, and I'm not a chemist by any stretch. Given the massive brain power in this thread, and the trouble that brain has been having getting this done, I'd say that using aluminum is very far away from cheating.

The halfway point, I guess, would be not to buy your aluminum powder but to giveyour 8 year old a file and send her out to the aluminum can bin.

White Yeti - 31-1-2012 at 16:36

I don't see how using aluminium is cheating. For most of us, we could only dream of having phosphorus to perform certain syntheses, regardless of the production methods employed.
Phosphorus is rarely an end product in and of itself, it is oftentimes a precursor.

Vikascoder - 7-2-2012 at 08:56

The above process will make white or red phosphorus

White Yeti - 7-2-2012 at 14:01

Quote: Originally posted by Vikascoder

The above process will make white or red phosphorus

[sarcasm] No, really? I didn't know that this thread was dedicated to making phosphorus. The title is really misleading. [/sarcasm]

Rogeryermaw - 16-2-2012 at 03:02

Quote: Originally posted by shannon dove

This is just my opinion, please do not get mad.
Using aluminium for any home chemical project is cheating ! Aluminium is more difficult to make than phosphorus. Using aluminium to make phosphorus is like buying red phosphorus then turning it into white phosphorus and bragging that you made white phosphorus. Its like getting someone else to make you some concentrated nitric acid and glycerin, then bragging that you made nitroglycerine.
If you use aluminium, the aluminium factory has done three/quarters of the work for you. Any post that talks about using aluminium, I do not even read it.

calling aluminum a cheat is rather silly. this entire site is dedicated to the idea of the home chemist doing what can be done with the chemicals that are available to us. so many of the interesting choices have been stripped from our hands. however, i challenge you to go to any major grocer or hardware store and find that aluminum is not readily available. it may take sturdier equipment and a lot more energy to purify, but the process itself is not much more complicated than the production of elemental phosphorus. it is perhaps easier when you consider the extreme danger posed by exposure to P4 and its fumes and gaseous compounds. yes, claiming to have made P4 by distilling P2 is a bit of a cheat since the concept is to start from no pure form of the element, but taking advantage of the position of Al in the reactivity series is just good chemistry sense.

by your logic, your posts are cheating if you did not build your computer, your monitor and generate your own electricity, run your own cabling, launch your own communications satellite with a handmade rocket and write your own software to tie it all together.

[Edited on 16-2-2012 by Rogeryermaw]

shannon dove - 20-3-2012 at 13:33

There was a method talked about a few pages back, that is mixing bone ash and charcoal then heat to redness, then pipe in hydrogen chloride gas, there is supposed to be immediate release of phosphorous.
I guess the HCl replaces the sand in the common industrial method.
I think maybe we should take another look at this method. It might work at a lower temp than the sand/charcoal/boneash method, but it probably will not work as good as the aluminum method. But its good to know different methods. Does anybody else think we should research this method further?

DJF90 - 27-3-2012 at 09:45

I was just wondering if anyone knows of a temperature (and pressure) for the vacuum sublimation of red phosphorus to the white allotrope. I know woelen demonstrates this at atmospheric pressure (sublimation temp according to wiki is about 416*C), but I was hoping for something a little more "gentle" - preferably below 250*C. I am unsure whether it may be calculated from standard data tables using thermodynamic equations.

CrEaTiVePyroScience - 14-4-2012 at 10:57

Well I don't see why everyone is looking that far to make phosphorus it's actually very common and you've hold it in your hand. Matchbox!

The sides of the box should contain phosphorus and glass. The head of the match should be potassium chlorate with possible sulfur , pyrotechnic binder (ex:dextrin) and maybe some other possible chemicals but haven't found them yet in the head of matches. I am talking about safety matches by the way (NOT strike anywhere matches).

So Ive done alot of research and expirements of getting a fairly pure and reasonable amount of phosphorus from matchboxes. Ill describe here my "tactic".
So first I tried to scrape off the phosphorus with just a knife but I would get ALOT of cartidge from the matchbox with it so ive tried alot of ways to avoid it and the best is to weathen it with acetone. Just dipping it for two seconds in acetone and you can easily scrape the phosphorus off with a creditcard. Then I came up against another problem , red phosphorus just isn't soluble in any material that I tested (ether, alcohol, water , carbon disulphide, alkali solutions) but I found it only soluble in concentrated nitric acid (best is fuming nitric acid but 70% (made by fract. distilation worked also for me)). So then I made a satured solution of it and filtered it through the finest filters I had. It worked perfectly!

So thats how I obtained my red phosphorus it isn't a very cheap method but you buy the cheapest match brand. Here in Belguim it's quite cheap (10small packs for 1.50euro) maybe check ebay or amazon for bigger amounts.

If you would have critism or any questions,suggestions please ask !
Btw: I will post a video about the whole proces on my youtube channel soon. And sorry for possible grammar faults, im from Belguim=)

White Yeti - 15-4-2012 at 09:44

@CrEaTiVePyroScience The purpose of the methods described above is not so much to obtain phosphorus, rather, the purpose is to demonstrate that phosphorus can be made at home. It is the process rather than the end result. To be honest, even though elemental phosphorus is chemical that is "nice to have" it doesn't have that many uses, especially for the amateur.

Question, do any of you have a concrete use for phosphorus (any of its allotropes) in any kind of synthesis?

Lambda-Eyde - 15-4-2012 at 10:08

Quote: Originally posted by White Yeti

Question, do any of you have a concrete use for phosphorus (any of its allotropes) in any kind of synthesis?

Both white and red phosphorus can be used to make the phosphorus halides, PX3, PX5 and POX3, which opens up a lot of synthetic routes not normally accessible to the amateur.

CrEaTiVePyroScience - 15-4-2012 at 10:11

@White Yeti.
Well that's true but I "collect" all chemicals Ive made and obtained just small samples of them in those 25ml duran glass bottles (at 174 now).
But I used it to make white phosphorus and to make the armstrong mixture and do experiments with armstrong mixture but besides that I don't really use it..

Polverone - 15-4-2012 at 14:13

Quote: Originally posted by CrEaTiVePyroScience

Then I came up against another problem , red phosphorus just isn't soluble in any material that I tested (ether, alcohol, water , carbon disulphide, alkali solutions) but I found it only soluble in concentrated nitric acid (best is fuming nitric acid but 70% (made by fract. distilation worked also for me)). So then I made a satured solution of it and filtered it through the finest filters I had. It worked perfectly!

You dissolved the red phosphorus in nitric acid? You have just oxidized it to phosphoric acid.

CrEaTiVePyroScience - 16-4-2012 at 07:47

@Polverone Ow that might be right ill do some extra experiments now and find out , ill let you know

BromicAcid - 7-5-2012 at 15:58

Tying up some loose ends.

As I read through the thread I found some blank spots in terms of information presented that could be filled by my somewhat recent acquisition of:

Mellor, Supplement to the Comprehensive Treatise on Inorganic and Theoretical Chemistry: Vol VIII Supplement III - Phosphorus. Longman Group Limited, 1971

Of special interest is the reduction of phosphates using hydrogen. Lead phosphate reduction is covered in patent literature but I haven't seen much on other phosphates so I will present that here:

(pgs 111-113)

Quote:

...many phosphates can be reduced by hydrogen at temperatures between 300° and 750°C. Metals which do not form phosphides, or give phosphides which are easily dissociated by heat, are the most susceptible to this reduction. In these reactions the metals is formed and the oxygen of the phosphate is quantitatively converted to water. Lead phosphates are particularly easy to reduce by hydrogen. For example, pyromorphite, 3Pb3(PO4)2*PbCl2, starts to react at 300°C and is completely reduced at 850°C.

Here is a reproduction of the table provided listing phosphates that are reduced at low temperature to phosphorus, the temperature listed is the temperature at which the reaction becomes rapid which was determined by looking at the increase of the partial pressure of water formed by the reaction:

Phosphate ........... Decomposition Temperature (°C)
BiPO4 ..................... 425
Ag3PO4....................425
SbPO4......................450
Pb4(PO4)2................575
3Pb3(PO4)2*PbCl2...600
Hg3PO4.....................600
Hg3(PO4)2................600
SnO2*P2O5..............600

Whereas metals that do form phosphides reduction with hydrogen will give a phosphide as an end product. A similar table is below reproduced in part:

Phosphate ........ Decomp. Temperature (°C) Products
Ni3(PO4)2.........................450........................P + Ni2P
CuPO3..............................600........................P + Cu3P + CuP2
Fe2P2O7...........................600........................FeP
Cu3(PO4)2........................300........................CuPO3 + HPO3
H3PO4 + SiO2...................550........................P

Onto another subject, thermal decomposition of phosphides. It was postulated early on by madscientist that heating certain phosphides could result in disproportionation to give a different phosphide along with elemental phosphorous. His example was:

4Cu3P2 ----> 4Cu3P + P4

Noting that heating copper (II) chloride gave copper (I) chloride and chlorine.

The text gives an equation showing disproportionation (pg 295) but no temperature is listed and a melting point is listed as 900°C for CuP2.

Heats of disproportionation are listed for several phosphides but decomposition temperatures are not listed for many.

Some examples of iron phosphides illustrate that perhaps these disproportionation reactions might not be the easy ticket that they appeared at first:

4FeP(s) ----> 2Fe2P(s) + P2(g) deltaH= + 72 kcal t=1200°C
4FeP2(s) ----> 4FeP(s) + P4(g) deltaH= + 66 kcal t=930°C

Zan Divine - 11-5-2012 at 13:35

Apologize ahead of time if this is out of place...but it is interesting.

I recently prepared this sample for a collector in California.
After working with Cs, this was a tame lil' pussycat.

[Edited on 11-5-2012 by Zan Divine]

Magpie - 11-5-2012 at 15:48

Quote: Originally posted by Zan Divine

I recently prepared this sample....

That's a fair amount of P. Did you make it, or just ampoule it?

SteveJones - 12-5-2012 at 15:12

Quote: Originally posted by White Yeti

@CrEaTiVePyroScience The purpose of the methods described above is not so much to obtain phosphorus, rather, the purpose is to demonstrate that phosphorus can be made at home. It is the process rather than the end result. To be honest, even though elemental phosphorus is chemical that is "nice to have" it doesn't have that many uses, especially for the amateur.

Question, do any of you have a concrete use for phosphorus (any of its allotropes) in any kind of synthesis?

On the contrary, reaction of phosphorous with bromine or chlorine will give rise to phosphorous trichloride/phosphorous pentachloride, which can be used when wanting to synthesize custom phosphine donors, or when wishing to synthesize acyl halides or anhydrides.

Zan Divine - 14-5-2012 at 06:15

Quote: Originally posted by Magpie

Quote: Originally posted by Zan Divine

I recently prepared this sample....

That's a fair amount of P. Did you make it, or just ampoule it?

I just purified the crude commercial material which was obtained, as initially condensed, under water. The P was melted, clarified by filtration through a SS screen to remove unmelted solids, ash and black specks, drawn up into 10 mL plastic syringes and allowed to freeze. The syringe fronts were cut off under water and the slugs were extruded using the plunger. This sample is 100 g and I would dearly have loved to treat it with chlorosulfuric acid to make it white instead of yellow before the owner took posession, but this acid requires oleum to make. And, yes, I know I could make the oleum but you have to draw the line somewhere and my current fascination is black P.

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