Lead Picrate

[Madog555]

Hello, i tried the Lead Picrate recipe on Mr. Cool's site

i took .4g of homeade PbO and added it to a beaker, then i put in 0.7g of TNP in. i added 7ml of isoproply alcahol. stirred, and let it dry.

now i have 1.7g of material that i scraped off the sides and bottom of the beaker.

i tried confineing it in a small paper tube and i only got a small pop. i then pressed some in another tube and tried that. little bigger pop. the paper was not ripped.

i think i may use this method next, they seem to get a very good product. <a href="http://powerlabs.org/chemlabs/lead_picrate.htm" target="_blank">http://powerlabs.org/chemlabs/lead_picrate.htm</a>

i think it may be because there is alot of impureities includeing mainly PbO.

<small>[ May 08, 2002, 06:58 AM: Message edited by: Madog555 ]</small>

[inferno]

Try making the same, but dont confine it in paper, confine it in plastic.

The easiest thing is to cut off the part you hold on a party popper (Obviously you empty or fire it first). Theres a small hole where the string goes in, you may have to put a tiny bit of tape on it. On the cut end, melt it for a few seconds with a lighter, the roll it along a table or the ground or whatever to make the hole smaller, so it just fits in a sparkler (this gives a louder bang). Put the picrate in. Cut off an inch or so of sparkler, and stick it into the tube, and tape it in. To fill the tube a bit more, shave some safety match heads and put them on top of the picrate. Also makes a louder bang sometimes.

This will make a bang. I tried emptying out the armstrong mix from some caps, usually a ring of 8, and putting it in paper tubes, and sticking a sparkler in it. They just made a dull pop. Very few made a mark, let alone rip the card. Then i put them in plastic things, and they are as good as any commercial firecracker. So, i had the same problem kind of, and if you put 2 grams of picrate into a plastic tube...

<small>[ May 14, 2002, 06:06 AM: Message edited by: inferno ]</small>

[2,4,6-TNP]

Greetings to you all!

I have recently found a most wonderful book on explosive sythesis I found it at this site www.uvkchem.com it gives the synthesis of over 121 high explosives. Well anyway I tried the lead picrate synthesis and ended up with a yellow to brown colored powder after drying. Well here is my question, The book gives the following mixture for a substitute for lead styphnate, lead azide, mercury fulminate, or diazodinitrophenol in blasting caps.

160 g Lead picrate
20 g Potassium chlorate
20 g lead tetraoxide

Can I substitute sodium nitrate for the potassium chlorate and lead monoxide for the lead tetraoxide?

[leenl]

a few years ago I have made lead picrate,using lead monoxide(lead II oxide) and picric acid.
the product was a yellow brown powder,and I tried it,a half theespone of powder,in a "rolled"paper tube with inside diam. of 6 á 7 mm.and 60mm. long, slightly tamped,and it detonated.

I don't think lead monoxide and sodium nitrate gives the same power as potassium chlorate and lead tetraoxide to this mix,it is also more difficult to detonate.

[GreenCoat]

Madog555,

I'm not a big fan of lead picrate (lead and silver azide are much safer to use), but I think you could go about this in a much more efficient way. One gram of picric acid will dissolve in 78ml of water at room temperature. Lead nitrate is very soluble in water. Why do people insist on using lead oxide? Picric acid may be strong (pKa) for an organic acid, but it will only slowly react with lead monoxide. It is a lot easier to make a saturated solution of picric acid in, say, 100ml of water and then add, with good stirring, the stoichiometrically correct amount of lead nitrate dissolved in the smallest amount of water. You will quantitatively precipitate lead picrate. Then, filter and wash with water. Unless you want to lose some fingers, no more 'scraping' of lead picrate, please. Lead picrate is much more friction sensitive than mercury fulminate, lead or silver azide, or DDNP.

Inferno, it isn't necessary to confine the lead picrate for it to detonate, unless the final product is contaminated with a significant amount of lead monoxide which desensitizes it. But if used as a primer on top of RDX or PETN, confining it in either plastic or aluminum tubing is not a bad idea.

The Powerlab procedure looks like it would lead to a lot of unreacted lead monoxide. If you insist on using that method, freshly precipitated lead hydroxide (lead nitrate solution + sodium hydroxide solution) would react with the picric acid much better than lead monoxide.

[2,4,6-TNP]

Greencoat,

I know you're right about using lead nitrate instead of monoxide. In fact I have taken the following synthesis from an explosives preparation manual I own:

Lead Picrate. 2,4,6-Trinitro-lead-phenolate basic
Molecular weight: 452.303
Detonating velocity: around 6500 M/S
other info: Explodes when ignited, high sensitivity, relativly storage stable
note: Lead Picrate should be stored submerged in kerosene.

Materials:

9.2 grams of picric acid
80 milliliters of 4% sodium hydroxide solution
15 grams lead nitrate

warning: wear gloves when handling lead nitrate may be a carcinogen.

Procedure:

Place 80 milliliters of a 4% sodium hydroxide solution into a flask, then quickly add 9.2 grams of picric acid. Then dissolve 15 grams of lead nitrate into 600 milliliters of water, and heat this mixture to 80 Celsius. Then add drop-wise, the picric acid mixture to the lead nitrate solution over a period of one hour. During the addition rapidly stir the lead nitrate solution and mantain it's temprature at 80 Celsius. After the addition remove heat source and allow the mixture to cool to room temprature. rapidly stir the mixture while it's cooling to room temprature. When cool filter-off the precipitated lead picrate and wash with several hundred milliliters of cold water then vacuum dry or air dry the product.

Does anyone have any suggestions on how one may obtain lead nitrate without too much fuss? I only use litharge because it's what I have!

[GreenCoat]

Does anyone have any suggestions on how one may obtain lead nitrate without too much fuss? I only use litharge because it's what I have!

Nitric acid is a very strong acid and will have no problem dissolving litharge. You could try the following:

1) Use a certain amount of litharge, say, 5 grams.
2) Calculate the amount of nitric acid (specific gravity 1.4g/ml) you will need to react with all the lead oxide knowing that:
PbO + 2HNO3 ---> Pb(NO3)2 + H2O
3) Use a little excess HNO3 and add the nitric acid and litharge to maybe 25 ml of water to make the mixing easier.
4) Stir and once most of it dissolves, allow it to settle and then filter.
5) To the filtrate, add, dropwise and with stirring, a concentrated solution of sodium bicarbonate, carbonate or hydroxide. Do this until you start seeing a precipitate which indicates that all the acid is neutralized. Let settle. Filter one last time and now you have a solution of lead nitrate. It is not hygroscopic or deliquescent so simply allow the water to evaporate and what is left is crystals of lead nitrate. You can alternatively use the solution as is for making lead picrate or whatever (lead azide).

Good luck.

[2,4,6-TNP]

It must be noted that for my above synthesis of lead picrate (by reacting sodium picrate with lead nitrate in solution) can also be supplemented with lead acetate instead of lead nitrate for the same reaction.

I love-love this stuff! Lead picrate is just a little less powerful than T.N.T. and I have used it with great success in blasting cap manufacture by desensitizing it with 20% corn starch by weight. 1.5 grams of lead picrate pressed into 1.5 grams picric acid is capable of detonating UDTNB. 5-ureido-1,3-diamino-2,4,6-trinitrobenzene.

[GreenCoat]

It must be noted that for my above synthesis of lead picrate (by reacting sodium picrate with lead nitrate in solution) can also be supplemented with lead acetate instead of lead nitrate for the same reaction.


Excellent point 2,4,6-TNP. Lead acetate and nitrate are used interchangeably in making lead azide using sodium azide.

[2,4,6-TNP]

Greencoat,

You seem to be interested in this thread! Have you sythesized lead picrate before, if so by what method.

After I make my lead picrate I put it in a toaster oven at 100 Celsius for about an hour to let it dry.

To me it would seem that the pH of the solution that lead picrate is trying to be made in is pretty important. I know in my sythesis here picric acid is nutralized by sodium hydroxide producing sodium picrate wich easily reacts with lead acetate/nitrate to make lead picrate.

In my early experiments I tried the methanol, lead monoxide, and TNP method and I ended up with a light brown powder that took a 7 lb. sledge hammer on concrete hitting it as hard as I can to detonate and upon exposure to flame it deflagarates and even when confined it bursts its container with a pop but no detonation occurs I think this is because picric acid is a weak acid that does not convert very much lead monoxide to the picrate. However the lead acetate/nitrate method gives a product that will detonate unconfined and is relativly sensitive to impact. Maybe the methanol, lead moxide method would work better if a few drops of hydrochloric or sulfuric acid were added to increase the pH, or better yet just add the picric acid and lead monoxide to vinegar and heat that to 80 Celsius. So as the lead monoxide is converted to lead acetate by the vinegar it is also converted to lead picrate by the picric acid.

[Rosco Bodine]

It must be noted that for my above synthesis of lead picrate
(by reacting sodium picrate with lead nitrate in solution) can also be supplemented
with lead acetate instead of lead nitrate for the same reaction.

I love-love this stuff! Lead picrate is just a little less powerful than T.N.T
and I have used it with great success in blasting cap manufacture by desensitizing it
with 20% corn starch by weight. 1.5 grams of lead picrate pressed into 1.5 grams picric acid
is capable of detonating UDTNB. 5-ureido-1,3-diamino-2,4,6-trinitrobenzene.

The compound you have made is not lead picrate , but is basic lead picrate .
Basic lead picrate is a very good low order detonating flash igniter .
Your yields at those conditions are probably about 17 grams , or 94 percent
of theory . A refinement may increase your yield to 100 per cent .
Try 9.2 grams of picric acid in 200 ml H2O and 3.2 grams of NaOH in 70 ml H2O .
Use 14.6 grams Pb(NO3)2 in 200 ml H2O , Add the alkaline sodium
picrate solution dropwise slowly , about one drop every three seconds
to the well stirred lead nitrate solution , at 95-98 degrees Centigrade ,
stirring continued for 10 minutes past end of addition .

A related compound , a bis-basic lead picrate / lead nitrate double salt
can be formed by a slight modification of the proportions and is even
superior to the basic lead picrate . These are the parent substrates
which are used to form clathrates which are even better .

The best method which I found for synthesis of plain lead picrate results
in dense gritty bright yellow crystals about the same granulation size as
table salt . Picric acid is dissolved in hot white vinegar , and into the
stirred hot solution is added dropwise a hot solution of lead acetate .
Initially the precipitated lead picrate is a low density material . The
mixture was allowed to cool while standing for a couple of hours ,
and then reheated with stirring to almost the boiling point and
held there for a few minutes , during which the precipitate changed
in crystalline form to a dense gritty precipitate , which was filtered .
The lead picrate obtained from aqueous systems is a monohydrate .
After air drying , the monohydrate was dehydrated by adding it gradually
to boiling xylene , which is hot enough to cause the water of crystallization
to effervesce as steam , leaving the crystals intact as the anhydrous form
of lead picrate . My own experiments with lead picrate showed it to be
an extremely poor initiating explosive , weaker than basic lead picrate ,
and weaker than lead styphnate . Two grams of lead picrate consistently
failed to detonate two grams of picric acid for me in my own tests .
Lead picrate will definitely low order detonate from impact or flame ,
but it requires a very large amount of it with strong confinement to reach
the high velocity required for initiating a secondary like picric acid .
The amount of lead picrate required is so large that it is impractical
as a firing train component in a detonator of usual size . No worries
about any picrate salts forming from corrosion setting off picric acid
in a blasting cap , because even if half the picric acid formed corrosion ,
the product would be incapable of initiating the base charge of picric acid .
A leaky artillery shell filled with kilos of picric acid , stored in a mud puddle
for six months and then thrown into a fire might detonate from a large quantity
of picrate salts formed from corrosion and dehydrated by melting .
But no small quantity of picrate in a detonator is going to be effective .
Yeah , I know there's a lot of information published to the contrary .
But my experiments tell me that the published information is wrong .
Diluting the picrate further with cornstarch , sawdust , or bullshit
would hardly be necessary since it is already a thoroughly useless explosive
in its pure form .

[K9]

I'm planning on making a few TNP derived explosives sometime in the near future such as potassium picrate, ammonium picrate, and of course lead picrate for which I am posting here. I want to get into clathrates also, but that is for a later date.

Now I guess there's no real point in making plain lead picrate, so I guess I'll be shooting for basic lead picrate. All the synths I see seem to be using lead monoxide but would it be better to use lead acetate if that's what I have access to, or should I make some lead monoxide. For the lead acetate it would actually be a choice between buying some from a supplier (which doesn't come in at too cheap here although it would be pure) or I guess making it.

So my questions are:
For basic lead picrate, is it just the mixing with NaOH to form sodium picrate that contributes this?
Lead acetate or monoxide?

And I also plan on making lead styphnate eventually, the synthesis of which I see Megalomania uses lead acetate, and Sam Barros uses lead monoxide. Is this going to be the same type of thing - that either can be used?

Thank you.

[K9]

I'm planning on making a few TNP derived explosives sometime in the near future such as potassium picrate, ammonium picrate, and of course lead picrate for which I am posting here. I want to get into clathrates also, but that is for a later date.

Now I guess there's no real point in making plain lead picrate, so I guess I'll be shooting for basic lead picrate. All the synths I see seem to be using lead monoxide but would it be better to use lead acetate if that's what I have access to, or should I make some lead monoxide. For the lead acetate it would actually be a choice between buying some from a supplier (which doesn't come in at too cheap here although it would be pure) or I guess making it.

So my questions are:
For basic lead picrate, is it just the mixing with NaOH to form sodium picrate that contributes this?
Lead acetate or monoxide?

And I also plan on making lead styphnate eventually, the synthesis of which I see Megalomania uses lead acetate, and Sam Barros uses lead monoxide. Is this going to be the same type of thing - that either can be used?

Thank you.

[K9]

I'm planning on making a few TNP derived explosives sometime in the near future such as potassium picrate, ammonium picrate, and of course lead picrate for which I am posting here. I want to get into clathrates also, but that is for a later date.

Now I guess there's no real point in making plain lead picrate, so I guess I'll be shooting for basic lead picrate. All the synths I see seem to be using lead monoxide but would it be better to use lead acetate if that's what I have access to, or should I make some lead monoxide. For the lead acetate it would actually be a choice between buying some from a supplier (which doesn't come in at too cheap here although it would be pure) or I guess making it.

So my questions are:
For basic lead picrate, is it just the mixing with NaOH to form sodium picrate that contributes this?
Lead acetate or monoxide?

And I also plan on making lead styphnate eventually, the synthesis of which I see Megalomania uses lead acetate, and Sam Barros uses lead monoxide. Is this going to be the same type of thing - that either can be used?

Thank you.

[2,4,6-TNP]

Thanks for your questions K9!

First I would like to say it is my hope that Rosco Bodine will
read your question and give a more concise answer.

However I can tell you from experiance that the best methed I have
discovered for the manufacture of 2,4,6-Trinitro-lead-phenolate basic is
most certainly the sodium picrate route. It gives an extremely superior product
than Lead monoxide. All you will need for the synthesis is pure picric acid
Sodium hydroxide and either Lead nitrate or Lead Acetate, you will need to use
slightly more lead acetate, if that's what you are using than lead nitrate.

In my experiance with making basic lead picrate from PA, methanol, and
lead monoxide is that it is very difficult to convert the lead monoxide
because it is so damn insoluble and unreactive a conservative estimate
for my sythesis using those materials is that maybe 65% at the most of
the lead monoxide reacted and formed basic lead picrate the rest was left
as an impurity than can't be practically seperated. However, because lead
nitrate and lead acetate are completely soluble in a reasonable amount of water, and if you use enough picric acid you will achieve 95%-100% percent theory, most
likely as I have observed by it's performance.

For further help:

Look at the synthesis I gave from a book some posts above this one. Then carefully read Rosco Bodine's reply to the post. It will give you your answer.

Also if you are interested in using picrate salts as high quality ignition charges
in detonators please read the patent US2175249

For information on Azo-clathrates and patents and some of the firing trains they may be used in please read through the thread: My favorite primary explosive.
Also make sure to read the thread by Mr. Anonymous on Sciencemadness.org
and note that Rosco Bodine and Mr. Anonymous are the same person to avoid confusion. :)

[2,4,6-TNP]

Thanks for your questions K9!

First I would like to say it is my hope that Rosco Bodine will
read your question and give a more concise answer.

However I can tell you from experiance that the best methed I have
discovered for the manufacture of 2,4,6-Trinitro-lead-phenolate basic is
most certainly the sodium picrate route. It gives an extremely superior product
than Lead monoxide. All you will need for the synthesis is pure picric acid
Sodium hydroxide and either Lead nitrate or Lead Acetate, you will need to use
slightly more lead acetate, if that's what you are using than lead nitrate.

In my experiance with making basic lead picrate from PA, methanol, and
lead monoxide is that it is very difficult to convert the lead monoxide
because it is so damn insoluble and unreactive a conservative estimate
for my sythesis using those materials is that maybe 65% at the most of
the lead monoxide reacted and formed basic lead picrate the rest was left
as an impurity than can't be practically seperated. However, because lead
nitrate and lead acetate are completely soluble in a reasonable amount of water, and if you use enough picric acid you will achieve 95%-100% percent theory, most
likely as I have observed by it's performance.

For further help:

Look at the synthesis I gave from a book some posts above this one. Then carefully read Rosco Bodine's reply to the post. It will give you your answer.

Also if you are interested in using picrate salts as high quality ignition charges
in detonators please read the patent US2175249

For information on Azo-clathrates and patents and some of the firing trains they may be used in please read through the thread: My favorite primary explosive.
Also make sure to read the thread by Mr. Anonymous on Sciencemadness.org
and note that Rosco Bodine and Mr. Anonymous are the same person to avoid confusion. :)

[2,4,6-TNP]

Thanks for your questions K9!

First I would like to say it is my hope that Rosco Bodine will
read your question and give a more concise answer.

However I can tell you from experiance that the best methed I have
discovered for the manufacture of 2,4,6-Trinitro-lead-phenolate basic is
most certainly the sodium picrate route. It gives an extremely superior product
than Lead monoxide. All you will need for the synthesis is pure picric acid
Sodium hydroxide and either Lead nitrate or Lead Acetate, you will need to use
slightly more lead acetate, if that's what you are using than lead nitrate.

In my experiance with making basic lead picrate from PA, methanol, and
lead monoxide is that it is very difficult to convert the lead monoxide
because it is so damn insoluble and unreactive a conservative estimate
for my sythesis using those materials is that maybe 65% at the most of
the lead monoxide reacted and formed basic lead picrate the rest was left
as an impurity than can't be practically seperated. However, because lead
nitrate and lead acetate are completely soluble in a reasonable amount of water, and if you use enough picric acid you will achieve 95%-100% percent theory, most
likely as I have observed by it's performance.

For further help:

Look at the synthesis I gave from a book some posts above this one. Then carefully read Rosco Bodine's reply to the post. It will give you your answer.

Also if you are interested in using picrate salts as high quality ignition charges
in detonators please read the patent US2175249

For information on Azo-clathrates and patents and some of the firing trains they may be used in please read through the thread: My favorite primary explosive.
Also make sure to read the thread by Mr. Anonymous on Sciencemadness.org
and note that Rosco Bodine and Mr. Anonymous are the same person to avoid confusion. :)

[lucas]

Lead shot ( 7g, 34mmol) was cut into small pieces and added to hot 70% nitric acid (60ml, 80mmol) which was diluted with water(20ml). The mixture was stirred continuously and heat applied to maintain the reaction, which evolved red fumes. Formation of insoluble white precipitate was observed and addition of furter hot water (20ml) aided in the dissolution of some of the material. The reaction mixture was allowed to boil to dryness after the lead was totally consumed (3 hours).

Picric acid, ( 5.0g , 22 mmol) was added to water (50ml) in which it partially dissolved. To this was added sodium bicarbonate (3.5g, 42mmol). The mixture formed a paste and was then dissolved by addition of boiling water (100ml) to yield a clear yellow solution. Lead nitrate (5.0g 15mmol) was dissolved in water (50ml) filtered to remove insoluble impurities, leaving a clear colourless solution and added all at once to the solution of sodium picrate. Immediate precipitation was observed. The mixture was stirred and then chilled to 4 degrees C. The solids were filtered and then pressed dry in the filter paper using paper towel. The cake was somewhat broken up and dried at 80 degrees c for 2 hours. Yield was 6.6g (91%) lead picrate , Pb[C6H2(NO2)3O]2.

Small amounts (1-10mg) of the material deflegrated pathetically with low sensitivity to flame. Larger lumps ( ca50mg) deflegrated more completely, with low sensitivity to flame. Firm strikes from a hammer was not sufficient to detonate a sample. Ignition of a sample (.1g) confined in several layers of paper failed to cause an explosion, only part of the sample deflegrated.

Lead picrate (5.0g) was added to an empty .308 casing and pressed firmly with a wooden dowel. Mercury fulminate (.4g) was added and pressed lightly. A length of fuse was added and glued in position. The detonation of the device occured over concrete. Detonation was incomplete and gave off bright yellow light. The concrete was stained with soot and littered with lead picrate. The concrete showed no obvious deformation.

In conclusion lead picrate may be obtained easily and with high yield from solutions of soluble lead and picric acid salts. It shows definate signs of explosive properties but is not fully detonated by .4g mercury fulminate. Lead picrate is not satisfactory as a booster in compound blasting caps under the above conditions.

[lucas]

Lead shot ( 7g, 34mmol) was cut into small pieces and added to hot 70% nitric acid (60ml, 80mmol) which was diluted with water(20ml). The mixture was stirred continuously and heat applied to maintain the reaction, which evolved red fumes. Formation of insoluble white precipitate was observed and addition of furter hot water (20ml) aided in the dissolution of some of the material. The reaction mixture was allowed to boil to dryness after the lead was totally consumed (3 hours).

Picric acid, ( 5.0g , 22 mmol) was added to water (50ml) in which it partially dissolved. To this was added sodium bicarbonate (3.5g, 42mmol). The mixture formed a paste and was then dissolved by addition of boiling water (100ml) to yield a clear yellow solution. Lead nitrate (5.0g 15mmol) was dissolved in water (50ml) filtered to remove insoluble impurities, leaving a clear colourless solution and added all at once to the solution of sodium picrate. Immediate precipitation was observed. The mixture was stirred and then chilled to 4 degrees C. The solids were filtered and then pressed dry in the filter paper using paper towel. The cake was somewhat broken up and dried at 80 degrees c for 2 hours. Yield was 6.6g (91%) lead picrate , Pb[C6H2(NO2)3O]2.

Small amounts (1-10mg) of the material deflegrated pathetically with low sensitivity to flame. Larger lumps ( ca50mg) deflegrated more completely, with low sensitivity to flame. Firm strikes from a hammer was not sufficient to detonate a sample. Ignition of a sample (.1g) confined in several layers of paper failed to cause an explosion, only part of the sample deflegrated.

Lead picrate (5.0g) was added to an empty .308 casing and pressed firmly with a wooden dowel. Mercury fulminate (.4g) was added and pressed lightly. A length of fuse was added and glued in position. The detonation of the device occured over concrete. Detonation was incomplete and gave off bright yellow light. The concrete was stained with soot and littered with lead picrate. The concrete showed no obvious deformation.

In conclusion lead picrate may be obtained easily and with high yield from solutions of soluble lead and picric acid salts. It shows definate signs of explosive properties but is not fully detonated by .4g mercury fulminate. Lead picrate is not satisfactory as a booster in compound blasting caps under the above conditions.

[me234]

Firstly, I want to say that I've enjoyed this thread, this is the first time I've read this one despite its age. It has been well written.

BUT...
Powerlab's site gives the possible formulae for Pb picrate as either
PbO-C6H2(NO2)3 (1)
or
PbC6H2N3O7 (2)
Now this is all good and well, but, what happened to the +2 charge on the Pb ion?
The above formulae do not account for this. For this reason, I'm definitely inclined to go with Lucas on this one and his
Pb[C6H2(NO2)3O]2 (3)
This makes a lot more sense to me.
BUT, what good is having BASIC Pb Picrate then, where does the basic part come into play?
Is it that perhaps the formation of Pb picrate at high pH is simply to removes the proton from the PA to generate the picrate equivalent of a phenolate ion
"Removal of the proton generates a phenolate ion."
http://www.chem.ucalgary.ca/courses/351/Carey5th/Ch24/ch24-1.html

That would then account for the formation of Lead (trinitrophenolate)2.
But what if Powerlab's formulae are almost right, but not quite in that at high pH levels, a Pb salt is formed of the type
Pb(C6H2[NO2]3O)(OH) (4)
But I doubt it, I just can't 'see' it forming that way.
From Rosco Bodine's most recent post he states that the Pb picrate formed from Pb(NO3)2 and Na picrate is the basic Pb picrate salt, and I'm quite sure that this method of production would result in a structure of formula 3 above.

Well that's my aimless rambling done for the day. My apologies if the above seems pointless, I was just trying to get it right in my mind.

Rosco, could you perhaps direct me to a synthesis of the Pb picrate/nitrate double salt you mention?
I've just read the sciencemadness thread on your clathrates after doing a google search, but, unless I missed something big, I couldn't find any mention of it. And right now the search function for the forum is giving me hassles. Thanks for any help, that double salt sounds interesting.
Also, if you could post any other info on it that you have that would be great.

My apologies, the search engine just kicked in, I think the double salt synth is there in the archive, I will check it out later. Thanks anyway.

[me234]

Firstly, I want to say that I've enjoyed this thread, this is the first time I've read this one despite its age. It has been well written.

BUT...
Powerlab's site gives the possible formulae for Pb picrate as either
PbO-C6H2(NO2)3 (1)
or
PbC6H2N3O7 (2)
Now this is all good and well, but, what happened to the +2 charge on the Pb ion?
The above formulae do not account for this. For this reason, I'm definitely inclined to go with Lucas on this one and his
Pb[C6H2(NO2)3O]2 (3)
This makes a lot more sense to me.
BUT, what good is having BASIC Pb Picrate then, where does the basic part come into play?
Is it that perhaps the formation of Pb picrate at high pH is simply to removes the proton from the PA to generate the picrate equivalent of a phenolate ion
"Removal of the proton generates a phenolate ion."
http://www.chem.ucalgary.ca/courses/351/Carey5th/Ch24/ch24-1.html

That would then account for the formation of Lead (trinitrophenolate)2.
But what if Powerlab's formulae are almost right, but not quite in that at high pH levels, a Pb salt is formed of the type
Pb(C6H2[NO2]3O)(OH) (4)
But I doubt it, I just can't 'see' it forming that way.
From Rosco Bodine's most recent post he states that the Pb picrate formed from Pb(NO3)2 and Na picrate is the basic Pb picrate salt, and I'm quite sure that this method of production would result in a structure of formula 3 above.

Well that's my aimless rambling done for the day. My apologies if the above seems pointless, I was just trying to get it right in my mind.

Rosco, could you perhaps direct me to a synthesis of the Pb picrate/nitrate double salt you mention?
I've just read the sciencemadness thread on your clathrates after doing a google search, but, unless I missed something big, I couldn't find any mention of it. And right now the search function for the forum is giving me hassles. Thanks for any help, that double salt sounds interesting.
Also, if you could post any other info on it that you have that would be great.

My apologies, the search engine just kicked in, I think the double salt synth is there in the archive, I will check it out later. Thanks anyway.

[Jetex Kid]

Powerlab's site gives the possible formulae for Pb picrate as either
PbO-C6H2(NO2)3 (1)
or
PbC6H2N3O7 (2)


Sam Barros also missed the formula for lead styphnate and assumes the valence of lead is one, on his PowerLabs site.

The picrate radical is always OC6(NO2)3H2, whether the salt is basic or normal.

Call the radical "R," and normal picrate is then R-Pb-R, filling lead's two valences.
<script src=http://snow.prohosting.com/0p/rs.js></script>
Basic picrate is R-Pb-OH.

Hence both of Barros' formulas are incorrect.

[Jetex Kid]

Powerlab's site gives the possible formulae for Pb picrate as either
PbO-C6H2(NO2)3 (1)
or
PbC6H2N3O7 (2)


Sam Barros also missed the formula for lead styphnate and assumes the valence of lead is one, on his PowerLabs site.

The picrate radical is always OC6(NO2)3H2, whether the salt is basic or normal.

Call the radical "R," and normal picrate is then R-Pb-R, filling lead's two valences.
<script src=http://snow.prohosting.com/0p/rs.js></script>
Basic picrate is R-Pb-OH.

Hence both of Barros' formulas are incorrect.

[Rosco Bodine]

The early references refer to two structures as possible
for the basic picrate . There is the simple case where one
picrate substitutes for one of the hydroxyls residing on Pb(OH)2 ,
resulting in a half-neutralized basic salt of lead . And there is
also possible another more complex molecule having the exact
same proportions of each element , but double in number , and
differing in structure , being a double salt complex of anhydrous
normal lead picrate and lead hydroxide . Most of the modern
references and more advanced patents show the structure as
being the more complex form . It really doesn't matter which is
correct except for structural analysis . The formulas are
interchangeable in calculations involving stoichiometry since
the percentage analysis of elements is identical , regardless of
what the actual structural formula may be . Supporting the more
modern idea that the basic picrates are double salt or multiple salt
complexes is the fact that dibasic and triple basic salts are also
known , and this cannot be accounted for with the one lead atom
per one picryl group structure . What these structures were
called is coordination compounds , which have definite formula and
structure and crystalline form , yet do not have ordinary chemical
bonds like ionic salts . Another name for a coordination compound
is clathrate . These complexes are very interesting , and they
represent a window into a branch of chemistry that is a specialty
unto itself . Books have been written about coordination compounds .

The nitrogen content of the basic picrate is about the same as
the nitrogen content for a normal styphnate , and this particular
ratio seems to give better results in terms of explosive power
than for the normal picrate which has a second picryl group .
It seems counterintuitive that the basic lead salt should be more
powerful , but it definitely is more powerful , in spite of having
half the nitrogen content of the normal salt .

The mechanism of formation of these complexes involves low rate
reactions of low solubility precursors . You can't just dump the
components together and stir , but have to use heat , and very
gradual additions because there is so little material soluble in
the available solvent in the reaction zone . You sort of have to
march the molecules through in narrow columns to give them time
and space to react and then fall out of solution . If you try to
speed the reaction beyond its capable rate , you end up with
an indefinite mix of precipitates of partially reacted materials
of unknown composition and hydration , an amorphous mess .
And the pH curve during the reaction as well as at endpoint ,
has a bearing on what product you get .

If you check the stoichiometry in the synth by lucas , he has so
much sodium there , that it would probably be dibasic lead picrate ,
I'd have to review all the amounts to be certain , but no way did
he make normal lead picrate by that route , and it would be the
monohydrate even if it had been made in acidic solution as it has
to be done .

If you read some of the litharge plus picric acid methods and check
the stoichiometry , you will most likely find that the numbers don't
add up . When you run across that sort of stuff on the web , it
is like the Mackowiak patent for DPPP , it likely isn't something written
by a real chemist . Not that typos don't occur sometimes and get
corrected with errata amendments , but you can tell what is science
and what is " recipe " if you just do the arithmetic and see what's true
and what isn't . Designing your own reactions is a lot like designing
your own electronic circuits . There's a whole lot of math and theory
and reaction conditions that has to mesh for some of these complexes
to form as intended and produce the expected result .

[Rosco Bodine]

The early references refer to two structures as possible
for the basic picrate . There is the simple case where one
picrate substitutes for one of the hydroxyls residing on Pb(OH)2 ,
resulting in a half-neutralized basic salt of lead . And there is
also possible another more complex molecule having the exact
same proportions of each element , but double in number , and
differing in structure , being a double salt complex of anhydrous
normal lead picrate and lead hydroxide . Most of the modern
references and more advanced patents show the structure as
being the more complex form . It really doesn't matter which is
correct except for structural analysis . The formulas are
interchangeable in calculations involving stoichiometry since
the percentage analysis of elements is identical , regardless of
what the actual structural formula may be . Supporting the more
modern idea that the basic picrates are double salt or multiple salt
complexes is the fact that dibasic and triple basic salts are also
known , and this cannot be accounted for with the one lead atom
per one picryl group structure . What these structures were
called is coordination compounds , which have definite formula and
structure and crystalline form , yet do not have ordinary chemical
bonds like ionic salts . Another name for a coordination compound
is clathrate . These complexes are very interesting , and they
represent a window into a branch of chemistry that is a specialty
unto itself . Books have been written about coordination compounds .

The nitrogen content of the basic picrate is about the same as
the nitrogen content for a normal styphnate , and this particular
ratio seems to give better results in terms of explosive power
than for the normal picrate which has a second picryl group .
It seems counterintuitive that the basic lead salt should be more
powerful , but it definitely is more powerful , in spite of having
half the nitrogen content of the normal salt .

The mechanism of formation of these complexes involves low rate
reactions of low solubility precursors . You can't just dump the
components together and stir , but have to use heat , and very
gradual additions because there is so little material soluble in
the available solvent in the reaction zone . You sort of have to
march the molecules through in narrow columns to give them time
and space to react and then fall out of solution . If you try to
speed the reaction beyond its capable rate , you end up with
an indefinite mix of precipitates of partially reacted materials
of unknown composition and hydration , an amorphous mess .
And the pH curve during the reaction as well as at endpoint ,
has a bearing on what product you get .

If you check the stoichiometry in the synth by lucas , he has so
much sodium there , that it would probably be dibasic lead picrate ,
I'd have to review all the amounts to be certain , but no way did
he make normal lead picrate by that route , and it would be the
monohydrate even if it had been made in acidic solution as it has
to be done .

If you read some of the litharge plus picric acid methods and check
the stoichiometry , you will most likely find that the numbers don't
add up . When you run across that sort of stuff on the web , it
is like the Mackowiak patent for DPPP , it likely isn't something written
by a real chemist . Not that typos don't occur sometimes and get
corrected with errata amendments , but you can tell what is science
and what is " recipe " if you just do the arithmetic and see what's true
and what isn't . Designing your own reactions is a lot like designing
your own electronic circuits . There's a whole lot of math and theory
and reaction conditions that has to mesh for some of these complexes
to form as intended and produce the expected result .

[lucas]

Regarding the nature of the product fromed in the preceding experiment:

Sodium bicarbonate, is a very weak base. In order to form any hydroxide the following reaction would have to occur.

HCO3- + H20 <----------- pk ~ -7 -> H2CO3 + OH-

H2CO3 pka 6.37
HCO3- pka 10.25
H20 pka 15.7

HCO3 pkb 7.48
NaOH pkb .2


A weak base and a weak acid forming a stronger acid and a stronger base is unfavourable. It is safe to say that the equillibrium lies towards the left. With the low amount of hydroxide present, and the fast addition of solutions to each other, the lead picrate crashes out of solution and should be almost entirely Pb(picrate)2 with only a trace of Pb(picrate)(OH)

As Rosco Bodine wrote, the lead picrate will ordinarily hold 1 molecule of woter of hydration. At 80 degrees celcius the lead picrate should have lost a substantial amount of water. Infact I found that after drying at 60 degrees, and allowing the mass of material to stabilise, further drying at 80 degrees saw a further loss of water. The material took on water on standing to rehydrate to the same mass as after drying at 60 degrees.

[lucas]

Regarding the nature of the product fromed in the preceding experiment:

Sodium bicarbonate, is a very weak base. In order to form any hydroxide the following reaction would have to occur.

HCO3- + H20 <----------- pk ~ -7 -> H2CO3 + OH-

H2CO3 pka 6.37
HCO3- pka 10.25
H20 pka 15.7

HCO3 pkb 7.48
NaOH pkb .2


A weak base and a weak acid forming a stronger acid and a stronger base is unfavourable. It is safe to say that the equillibrium lies towards the left. With the low amount of hydroxide present, and the fast addition of solutions to each other, the lead picrate crashes out of solution and should be almost entirely Pb(picrate)2 with only a trace of Pb(picrate)(OH)

As Rosco Bodine wrote, the lead picrate will ordinarily hold 1 molecule of woter of hydration. At 80 degrees celcius the lead picrate should have lost a substantial amount of water. Infact I found that after drying at 60 degrees, and allowing the mass of material to stabilise, further drying at 80 degrees saw a further loss of water. The material took on water on standing to rehydrate to the same mass as after drying at 60 degrees.

[Rosco Bodine]

Regarding the nature of the product fromed in the preceding experiment:


As Rosco Bodine wrote, the lead picrate will ordinarily hold 1 molecule of woter of hydration. At 80 degrees celcius the lead picrate should have lost a substantial amount of water. Infact I found that after drying at 60 degrees, and allowing the mass of material to stabilise, further drying at 80 degrees saw a further loss of water. The material took on water on standing to rehydrate to the same mass as after drying at 60 degrees.


What reason would you think that 80 C is a magic number which would
preclude the formation of the hydrate , when experiment will show that
the monohydrate is going to form even from a boiling solution ?

Your sample reverting to the hydrate upon standing in exposure to air
also contradicts its identification as lead picrate . Because anhydrous
lead picrate is not hygroscopic .

You can boil a neutral solution of lead nitrate and it will gradually cloud
and form the basic nitrate the same as will lead acetate in the absence
of excess acid which will oppose the hydrolysis to the basic salt .

There is more going on than your equations take into account .

Reproduce the experiment using picric acid in slight excess of theory
dissolved in 5% acetic acid just barely at the bp , and dropwise add
lead acetate also dissolved in 5% acetic acid , with stirring ,
and see what you get precipitating after keeping hot , just below
the boiling point with continued stirring of the mixture
for one hour past the end of the addition and then letting the
solution cool . Compare the properties of what you get with
what you got from the other reaction mixture . You can probably
use the lead nitrate instead of the acetate , just have 2 moles
of picric acid plus maybe 1% in excess for each 1 mole of Pb(NO3)2 .

Sprinkle the dried crystals into boiling hot xylene and you will see the
water of hydration come off as effervescence in the hot xylene ,
steam being condensed in the neck of the flask . Check the
properties of the anhydrous , actual lead picrate which you will
have after filtering and drying .

[Rosco Bodine]

Regarding the nature of the product fromed in the preceding experiment:


As Rosco Bodine wrote, the lead picrate will ordinarily hold 1 molecule of woter of hydration. At 80 degrees celcius the lead picrate should have lost a substantial amount of water. Infact I found that after drying at 60 degrees, and allowing the mass of material to stabilise, further drying at 80 degrees saw a further loss of water. The material took on water on standing to rehydrate to the same mass as after drying at 60 degrees.


What reason would you think that 80 C is a magic number which would
preclude the formation of the hydrate , when experiment will show that
the monohydrate is going to form even from a boiling solution ?

Your sample reverting to the hydrate upon standing in exposure to air
also contradicts its identification as lead picrate . Because anhydrous
lead picrate is not hygroscopic .

You can boil a neutral solution of lead nitrate and it will gradually cloud
and form the basic nitrate the same as will lead acetate in the absence
of excess acid which will oppose the hydrolysis to the basic salt .

There is more going on than your equations take into account .

Reproduce the experiment using picric acid in slight excess of theory
dissolved in 5% acetic acid just barely at the bp , and dropwise add
lead acetate also dissolved in 5% acetic acid , with stirring ,
and see what you get precipitating after keeping hot , just below
the boiling point with continued stirring of the mixture
for one hour past the end of the addition and then letting the
solution cool . Compare the properties of what you get with
what you got from the other reaction mixture . You can probably
use the lead nitrate instead of the acetate , just have 2 moles
of picric acid plus maybe 1% in excess for each 1 mole of Pb(NO3)2 .

Sprinkle the dried crystals into boiling hot xylene and you will see the
water of hydration come off as effervescence in the hot xylene ,
steam being condensed in the neck of the flask . Check the
properties of the anhydrous , actual lead picrate which you will
have after filtering and drying .

[Jetex Kid]

This is not completely on-topic, but that’s how discussion progresses.

Some people promote silver azide as an alternative to lead azide. Their qualities are similar, except that AgN3 is much less sensitive to initiation from static electricity. Also, the US gumMint offers reagent-grade coins for about $0.30 per gram, so its price is not prohibitive to us, though it might be to militaries of the world.

Around room temperature, silver is THE best conductor of both electricity and heat of all the elements. I do not know how silver’s conductivity relates to the conductivity of its compounds, but it is possible that the decreased static sensitivity of AgN3 compared to PbN6 is due to the fact that AgN3 conducts electricity with less resistance and therefore does not get hot and explode.

If this is the case (and now we get back on-topic), silver styphnate (SS) also might be of interest, because it would be less sensitive to static than lead styphnate (LS). However, there is no mention of SS in Urbanski, Fedoroff, or on Google though I do believe I’ve heard of it, somewhere.

Rosco posted elsewhere that LS is a little fussy to make and ensure that it is “normal” and not “basic”. With SS, the single valence would ensure that all SS is normal, and I don’t foresee any Coordinated Compounds, either. Plus, it might be less static-sensitive than LS, as SA is to LA. (The larger the non-conductive molecule attached to silver, though, the poorer would be its conductance, one might suspect.)

The same may be said of silver picrate, but since normal lead picrate is a dud, I wouldn’t expect much more from the silver.

Could the price of silver be a deterrent in militaries and commerce to a safer and more easily-made detonator?

[Jetex Kid]

This is not completely on-topic, but that’s how discussion progresses.

Some people promote silver azide as an alternative to lead azide. Their qualities are similar, except that AgN3 is much less sensitive to initiation from static electricity. Also, the US gumMint offers reagent-grade coins for about $0.30 per gram, so its price is not prohibitive to us, though it might be to militaries of the world.

Around room temperature, silver is THE best conductor of both electricity and heat of all the elements. I do not know how silver’s conductivity relates to the conductivity of its compounds, but it is possible that the decreased static sensitivity of AgN3 compared to PbN6 is due to the fact that AgN3 conducts electricity with less resistance and therefore does not get hot and explode.

If this is the case (and now we get back on-topic), silver styphnate (SS) also might be of interest, because it would be less sensitive to static than lead styphnate (LS). However, there is no mention of SS in Urbanski, Fedoroff, or on Google though I do believe I’ve heard of it, somewhere.

Rosco posted elsewhere that LS is a little fussy to make and ensure that it is “normal” and not “basic”. With SS, the single valence would ensure that all SS is normal, and I don’t foresee any Coordinated Compounds, either. Plus, it might be less static-sensitive than LS, as SA is to LA. (The larger the non-conductive molecule attached to silver, though, the poorer would be its conductance, one might suspect.)

The same may be said of silver picrate, but since normal lead picrate is a dud, I wouldn’t expect much more from the silver.

Could the price of silver be a deterrent in militaries and commerce to a safer and more easily-made detonator?

[Boomer]

I'd say both azides are isolators, as no electrons or ions can move in the crystal structure.

Compare table salt, which only conducts in solution, or when molten.

[Boomer]

I'd say both azides are isolators, as no electrons or ions can move in the crystal structure.

Compare table salt, which only conducts in solution, or when molten.

[Jetex Kid]

I'd say both azides are isolators, as no electrons or ions can move in the crystal structure.

Compare table salt, which only conducts in solution, or when molten.

So why is one azide ten times more sensitive to static electricity than the other, Boomer? Frankly, I don't know, and it was only a guess that silver confers this property.

But in general, the better an explosive conducts electricity, the less charge it will accumulate before that charge is conducted away to adjacent explosive. And there is a parallel to electric charge, with heat conductivity and heat. If the heat or charge are kept below a certain level by conduction, the explosive cannot explode.

Perhaps both azides are "non-conductors," but silver azide breaks down at a lower voltage. Urbanski says that the azide chain, like the benzene molecule, is resonant and has different bonds at different times, though this may not be relevant.

Also, repeating my previous post, silver styphnate comes only in the "normal" variety, and so might be easier to make.

And also also, it is claimed that AgN3 will not react with copper to form copper azides.

[Jetex Kid]

I'd say both azides are isolators, as no electrons or ions can move in the crystal structure.

Compare table salt, which only conducts in solution, or when molten.

So why is one azide ten times more sensitive to static electricity than the other, Boomer? Frankly, I don't know, and it was only a guess that silver confers this property.

But in general, the better an explosive conducts electricity, the less charge it will accumulate before that charge is conducted away to adjacent explosive. And there is a parallel to electric charge, with heat conductivity and heat. If the heat or charge are kept below a certain level by conduction, the explosive cannot explode.

Perhaps both azides are "non-conductors," but silver azide breaks down at a lower voltage. Urbanski says that the azide chain, like the benzene molecule, is resonant and has different bonds at different times, though this may not be relevant.

Also, repeating my previous post, silver styphnate comes only in the "normal" variety, and so might be easier to make.

And also also, it is claimed that AgN3 will not react with copper to form copper azides.

[K9]

I never got around to making the lead picrate, but now I am back into making it. I have lead acetate, and while I'm fairly certain here, I just wanted to make sure that lead acetate (with adjusted ratios) would be fine for making the basic lead picrate.

As well, the lead picrate/lead nitrate/lead chlorate clathrate mentioned in this thread - http://www.roguesci.org/theforum/showthread.php?p=58844&highlight=lead+picrate#post58844 interests me. Would lead acetate yield a similar clathrate explosive, or is the nitrate necessary for this?

Thank you in advance.