Sciencemadness Discussion Board

Lead Picrate

Madog - 30-11-2002 at 15:19

today i made some lead picrate, i took 1.2g of PbO, some isoproply alcahol and 2g of TNP and mixed them together, then i put it on my little hotplate made from a cofee machine and heated it, i stired and swirled it as it boiled a little. this whent on for about 6 minutes, then i shut the plate off and came back to it 20 minutes later to find that the isoproply alcahol kinda gelied. i shifted it around a bit and it mixed, this cause it to solidify more so if u tiped it upside down it wouldnt move (i later read that this would happen on powerlabs). then i let it sit for a couple more minutes and poured some more isoproply alcahol on it, mixed it around and filtered. i washed it with more alcahol. now its in the filter still wet and gooey, there seems to be a good amount there. i took a little and lit it, the alcahol burnt off and the lead picrate ignited with a pop and a crackle. it gave that nice characteristic purple flame that picrates have

this should be dry tomarrow for me to play with it, i will tell you the results:D

ShockWave - 30-11-2002 at 15:41

Sounds good to me !

Can someone tell me for how long this can be stored dry or wet ?

trinitrotoluene - 30-11-2002 at 16:25

I don't think you can store it for that like maybe like a few months. I think all picrates tend to become quite senistive as they age.

Madog - 30-11-2002 at 16:41

hrm, its relatively storage stable, i had potassium picrate stored for months. maybe i will put a little lead picrate aside for a couple months and see what hapens, do a little sensitiveity tests and stuff. i would like to see if this is a suitable primary, the main reason it interests me is because its easy to make and seems more or less storage stable, at least alot more than AP.

btw, the ratios and structure of lead picrate on powerlabs is wrong, i basicaly used his procedure with the real ratios and it seems to have worked well, i put it in my boiler room (the place with the heater thing for the house, its great for drying) and i cant wait to play with it

Science of sensitization

Ramiel - 1-12-2002 at 06:42

Could someone kindly explain the science behind sensitization, is it to do with a change in structure, reaction with the atmoshpere, or just dehydration/hydration?

kingspaz - 1-12-2002 at 08:24

watch out for Pb vapour when the stuff burns....can't be good for the brain cells...
if there is any change in sensitivity it will be down to hydration/dehydration. the salts should mimic TNP in storage stability. this means they are storage stable as a sample of TNP has not shown signs of deteriorating from 1860 (some date like that).
can anybody tell me why TNP refuses to react with Fe2O3?

vulture - 1-12-2002 at 09:02

Maybe because three TNP molecules on one iron is too strained? Besides, oxides are rather unpredictable species when reacting with acids. I would try iron(II)carbonate if I were you.

Madog - 1-12-2002 at 11:46

wow, thats a long time, i was always lead to believe that TNP would last for years but after a while it would become unstable.

i pressed a little lead picrate 9in a .40 caliber shell and crimped the front (there was only a little, it was plenty far away from the place where it was crimped) i set it off in the sand box and it exploded nicely, i didnt find any shrapnel tho so the next one is gona go in a can or something, i wana see how deformed it is. has anyone ever used lead picrate to detonate anything? i might try useing a gram or so to detonate some PETN or MEKP dynamite.

kingspaz - 1-12-2002 at 13:28

if you pressed the lead picrate onto the PETN then you'd only need 0.25-0.5g and that would be plenty enough. less primary = less chance or premature detonation.

Madog - 1-12-2002 at 15:28

ok, cool, i think i will try that. itts pretty shock sensitive, i hit some with a hammer, it actualy seems less shock sensitive than AP though, which doesnt really surprise me, especicialy sience the lead picrate isnt really crystaline

sensitive of MEKP

alien14305 - 2-12-2002 at 19:50

Hey madog, i read about MEKP dynamite in a post, i was wondering just how sensitive and stable is MEKP and ammonium nitrate? I have been thinking about making some for fun but i am scared of the sensitivity of it being a peroxide.

Madog - 3-12-2002 at 12:35

hey, i pressed some lead picrate into a .22, and taped it to another .22 of pressed PETN so the open end of each cartridge were together. i put this in a soda can and it didnt det the PETN, just made a pop.

hey alien. i have never detonated MEKP other than just hitting little pieces of paper soaked in it with a hammer, it is pretty sensitive. i have only made it twice and the reason i was gona use the lead picrate to detonate some is because its easy for me to make and quick. i have never put it in AN but it would be qite sensitive, especialy if you have a high percentage of MEKP. its sensitive, and dangerous but if you are willing to make AP then you should definately be willing to make MEKP.

mekp dynamite

alien14305 - 3-12-2002 at 14:39

Maddog, here is my idea about mekp dynamite. I want to roll some paper tubes 9.5 inches long and 1.25 inches diameter outside. I will fill it up with 11 grams mekp to 100 grams ammonium nitrate (i don't think the tube will hold this much). I'll close both ends and when i want to use it punch a hole in the end and insert a 1 gram mekp cap into it. I am sort of worried of punching a hole in the dynamite, inserting a cap. You think this will set the mixture off? I have done this 2 times with APAN and it didn't go off. You think this is a bad idea? From your post it sounds like mekp is a bit less sensitive then AP.

Madog - 3-12-2002 at 15:56

hmm, do u mean if it would be dangerous to shove the cap in? no, i wouldnt say it is, people shove caps into comercial dynamite. i would shove it in, its not gona be sensitive to friction when absorbed in AN enough to go off. its good to play it safe tho, you only get one body. if you are refering to the 1 gram of MEKP setting off the dynamite it would work.

you have had 2 failed ignitions with APAN? or did u mean u shoved the cap into APAN 2 times and you still have hands?

do you plan to make solid MEKP for detonators? or to use KNO3/NaNO3 with MEKP soaked in it? HIgh concentration of MEKP in KNO3 is supose to be detonateable by flame.

alien14305 - 3-12-2002 at 17:00

I didn't just shove it into the apan. My friend loads them cause he is quicker then I am and he pushes it in. He pushes it into the 15% AP apan but he is really careful and does it slow. They have failed both times. My plan was just to put 1-1.5 ml of mekp it without anything mixed in just the liquid. I really don't want to have to press it so I am planning to use the liquid in the cap only. I know what .4 grams AP going off in your hand can do to you. If i mix it with KNO3 will it be less sensitive? I am not even gonna crimp the cap shut, i will try to use culk of some thing else that hardens to close the cap and hold the fuse it. Using the 11gram-100gram ratio you think it is less sensitive then commercial dynamite? How do you think MEKP sensitivity compares to nitroglycerine?

Madog - 3-12-2002 at 18:43

it will be less sensitive to shock if absorbed in KNO3, and it wont roll around make have friction. it will probaly be less sensitive then comercial dynamite. was ur AN damp for those charges? NG is similar in sensitiveity i to MEKP i believe, iwould like to do some tests compareing the sensitiveity. i dont have much experiance with either of them so i cant say now.

Madog - 3-12-2002 at 18:44

oh yes, i tried to detonate some lead picrate when it was confined in paper and it failed. i think im just gonna try detonateing all the lead picrate i have at once in a medicine bottle.

alien, we should take this conversation to the MEKP thread

kingspaz - 4-12-2002 at 11:35

the reason it failed to initiate the PETN is because it had a few mm of metal between the two explosives. this has a dramatic effect on initiation. press the lead picrate ON the PETN. so its in direct contact. then when the lead picrate goes off the PETN will go with it.

Madog - 4-12-2002 at 14:09

no, the neck of each cartridges were together, they were in complete contact. doing that backwords would be stupid.

it looked like this

-----i====i
\
fuse

Ramiel - 8-12-2002 at 21:57

Hey, I used an ounce (that's 50 tonnes) of Leadmanganesediphoropentanoate to detonate a sandbox too!! it was k3wl!!!!

Anarchy 4 eva, RoX0r d3y boX0r

If someone can please tell me how these stories about the proverbial campfire are contributing to scientific knowledge, please tell me now and save me the embarrasment.

Please try to keep these discussions on topic, and stop what is an awesome forum degenerating into another EW forum.

kingspaz - 10-12-2002 at 14:00

'degenerating into another EW forum'
what the fuck? you act like the forum is k3\/\/|_ and a bad place. you are obviously mistaken.

Ramiel - 12-12-2002 at 23:04

Ok, forget it.

Just that EW is only explosives/weapons.

madscientist - 13-12-2002 at 12:22

I do think that Ramiel may have had a valid point.

This energetic materials forum is more about the chemistry of energetic materials; the E&W Forum is more about the application/usage of energetic materials. Obviously some discussion of the properties of energetic materials is acceptable here, such as discussion of how sensitive they are to various blasting caps, etceteras. But I do think that we should try to avoid having this forum transform from the discussion of chemistry to discussion of the usage of bangs and whizzes.

PHILOU Zrealone - 13-3-2003 at 06:43

To make picrate better use double salt reaction! Na or NH4 picrate are reacted with soluble nitrate, acetate or sulfate salts of the desired compound!

Best is to ask here what you want!

I wouldn't heat a picrate or a combination of products that might provide it!

Madog - 15-3-2003 at 12:26

i have comcluded that lead picrate is a shitty explosive once and for all. i made it a few days ago via Na picrate solution + lead acetate solution and it still sucks, i also tryed to dry it well, oh well, screw lead picrate.

PHILOU Zrealone - 24-3-2003 at 06:35

You need a slight excess of TNP otherwise your Na picrate is in basic media and most of your precipitating Pb picrate will be polluted by Pb(OH)2!!!! That's for sure what you had!
:cool::mad::cool::mad::cool:
:o:o:o:o:P:P:P:D:D:D;););):):):):cool::cool::cool:

Madog - 26-3-2003 at 12:54

yeah, but that conclusion was a result of all of my lead picrate experiments.

osamafon - 27-3-2003 at 00:22

what do you think obout Al or Pb4+ picrates?

PHILOU Zrealone - 27-3-2003 at 16:33

Both look good to me!
OB is improved in Pb(picrate)4 vs Pb(picrate)2 since PbO is the thermidynamically stable oxyde!But the first one may suffer of a slightly lower density!

I also like...Al(N3)3

Al(N3)3 --> 9/2N2 + Al(atomic)+ heat
2Al(atomic)+ heat -air-> Al2O3 + a lot of heat

:P:P:P:D:D:D;););):o:o:o:cool::cool::cool:

chemoleo - 26-7-2003 at 23:40

hmm... u definitely won't be able to make pure Alpicrate in aqueous solution. after all, dissolve Al in HCL and u get some Al-OH-HCl complex. AlCl3, in its pure form, is I think made by reacting chlorine gas with Al. THis type of AlCl3 is an extremely strong H2o binding compound, and thus of interest to many organic reactions. .. probably the same applies to Al(N3)3, I would bet my money's worth that you can't prepare it in its pure state in aqueous solution ... sorry :(

Smoer - 8-2-2005 at 11:38

Wy do you need a salt/oxide of lead to make lead picrate??
TNP is an acid so shouldn't it react with Pb also?

neutrino - 8-2-2005 at 14:39

This doesn’t work because organic acids are generally very weak. Even TNP (a very strong organic acid because of the nitrate groups drawing the electron cloud and allowing that one hydrogen to protonate) couldn’t attack the metal with any real speed, if at all.

Bert - 8-2-2005 at 15:21

Numerous accidents resulting from the contact of picric acid and Lead are reported. It certainly WILL attack Lead sufficiently to produce Lead picrate in sufficient quantities to detonate the remaining picric acid! See Maxim's "Dynamite tales" for an early account-

To put things in perspective about picrates ,

Rosco Bodine - 9-2-2005 at 14:19

and SEE just how unlikely it is that picric acid would be detonated accidentally by the presence of metallic picrates which may form in situ from reaction of picric acid with corrosion of metals , ......

TRY to DELIBERATELY detonate picric acid using a separately made and loaded metallic picrate of any variety , in any reasonable amount and see if you can succeed in securing the detonation of the picric acid . I'll bet you either won't succeed or it will require some pretty extreme conditions to get even a partial detonation of the picric acid
* deliberately * using a metallic picrate as an initiator . I have experimented with this and came to the conclusion it would probably require an enormous amount of corrosion in some very large items of ordnance , subsequently subjected to very great mechanical stress or even exposed to very high temperatures like
a * fire * for example , to produce such
" accidental " detonations associated with
picric acid . The danger of such an occurrence is greatly exaggerated by the literature .

Bert - 10-2-2005 at 10:06

Prior to the use of salycilate and benzoate fuels with perchlorate oxidizers for pyrotechnic whistles, Potassium picrate mixtures were used. Lead ramming blocks were also typical pyrotechnic factory equipment at that time- In a fireworks factory, the difference between a low order explosion incapable of detonating straight picric acid and a high order one so capable would not be meaningful as you'd have an explosion/fire/dead or injured workers regardless. That's my background. Hiram Maxim's late 19th century report of an associate's accident resulting from a leaking wooden keg of picric acid and a lead water line also would not have required a true detonation- 20kg of burning picric acid in an explosives plant would be quite exciting enough...

Lead styphnate

SAM4CH - 17-2-2005 at 03:09

What is the exact ratio of lead monoxide/styphnic acid needed to make lead styphnate using Ethanol as solvent for Styphnic Acid?

Re: Dynamite Stories

Bert - 23-2-2005 at 12:59

Correction- Dynamite Stories was written by Hiram Maxim's BROTHER- Hudson Maxim. I hope nobody wasted time looking for it under the wrong name. The book is available here if anyone is interested. It includes a first hand account of Hudson's blowing his hand off with Mercury fulminate as well as other interesting errata. His secretary commented after- "You too are now a "shorthand" writer..."

freedompyro - 13-1-2012 at 02:32

How stable is the anhydrous version of lead picreate? No spontaneous decomposition or anything like peroxides I would assume.

Also, what is the difference between lead picreate synthesized with lead monoxide vs lead trioxide?

Pulverulescent - 13-1-2012 at 02:50

Quote:
How stable is the anhydrous version of lead picreate?

Valuing certain fairly essential bits of my anatomy, I sure wouldn't mess with it!!!

P

grndpndr - 13-1-2012 at 08:30

Quote: Originally posted by Rosco Bodine  
and SEE just how unlikely it is that picric acid would be detonated accidentally by the presence of metallic picrates which may form in situ from reaction of picric acid with corrosion of metals , ......

TRY to DELIBERATELY detonate picric acid using a separately made and loaded metallic picrate of any variety , in any reasonable amount and see if you can succeed in securing the detonation of the picric acid . I'll bet you either won't succeed or it will require some pretty extreme conditions to get even a partial detonation of the picric acid
* deliberately * using a metallic picrate as an initiator . I have experimented with this and came to the conclusion it would probably require an enormous amount of corrosion in some very large items of ordnance , subsequently subjected to very great mechanical stress or even exposed to very high temperatures like
a * fire * for example , to produce such
" accidental " detonations associated with
picric acid . The danger of such an occurrence is greatly exaggerated by the literature .


Most of us have seen the'black books ' that deal with a mech mixture of TN/Litharge being used as a detonator.
As well many of us have seen a paper I believe produced by
Remington Arms for Picatinny Arsenal in which 2gr of mech mixture of litharge /TNP
were placed in a cartridge case Im assuming with some BP or SP as an ignition mix.The 2gram improvised det caused 50gr
of strongly confined lightly pressed, TNP to detonate high order.The found pieces of the container proved that it was a high order det(a picture of recovered steel pieces is included in report).Thats hard to argue with unless were to disbelieve Rem. Arms/picatinny arsenal official reports-documents.
Forget about all that for a moment and those of you who are experimenting with these mixes of TNP/Litharge take about a 1/4 gr wrap the mix in AL foil and place on a HP.If you value your HP place a piece of metal between the burner and packet of TNP or it could well destroy your electric HP.Ask me how I know.I also tried filling a .22lr case with the TNP/PB0
mix and cooking that off.In order to catch any fragments I
placed the case inside a tin can.As always the mix detonated violently no part of the case could be found only about a dozen small holes in the tin can from small case fragments.
I believe what this means is exactly what roscoe alluded to that it required extreme conditions for the lithage /TNP mixture to detonate TNP, like a fire or extreme heat that could be provided by a good amount of an ignition mix.I dont believe the mech mixture produces lead picrate at all.What Ive seen isnt sensitive to friction in the slightest and requires a very stout hammer blow to det.The same as plain TNP IMO.But confine the mix slightly and heat itv to the point of TNP melting/mixing with PB0 and a violent det occurs.

I looked up the document I was referring to which I believe is somewhere on the forum.
AD410399, (TNP/Litharge USMIL Imp Det)
Monthly report, #2
'Development of explosives and Initiators for special operations warfare.' Remington arms co for Picatinny arsenal
Dover NJ, may 1963
Also in the report the researchers report success with nitrating 'zerex' antifreeze under field conditions using AN/boiled down battery acid!

[Edited on 13-1-2012 by grndpndr]

[Edited on 13-1-2012 by grndpndr]

freedompyro - 28-1-2012 at 02:52

Is Lead Picrate compatible in mixing with ETN, MHN and other nitrates or does it act to catalyze it's breakdown? Picric Acid being acidic leads me to ask this question.

[Edited on 28-1-2012 by freedompyro]

quicksilver - 28-1-2012 at 12:25

Quote: Originally posted by freedompyro  
Is Lead Picrate compatible in mixing with ETN, MHN and other nitrates or does it act to catalyze it's breakdown? Picric Acid being acidic leads me to ask this question.

[Edited on 28-1-2012 by freedompyro]


The question would also have some conditional issues. Does the nitrated material have an anti acid, does it have a stabilizer? Is this a scenario of shelf-life?

It's not a common practice to ever place a nitric ester with an acidic substance, regardless of the conditions.

I had once read a patent for a "container-less" detonator, yet it was sealed within a shell of polymer (PBX). This may also be one of the utilitarian aspects of polyester in smokeless powder.

freedompyro - 28-1-2012 at 13:39

No anti-acid. This is a scenario of picrate salts catalyzing the breakdown of nitrated materials rendering them storage unstable.

I just attempted to synthesize lead picrate with 10g 95% Ethanol and 1.2g of Pb3O4 and then a second synthesis with 1.2g PbO.

The Pb304 synthesis failed for some reason... The resulting product is still red. The issue may be that ethanol does not work with Pb304 or that the product was not heated for long enough.

The Lead Picrate from the PbO synthesis won't go high order when initiated by flash... Are you guys sure about the 1.2g PbO? Both megalomania and powerlabs say 1-1 ratio of picric acid to PbO... It won't sustain deflagration either. It just melts and goes POP with a small flame then goes out before it all is burned. Further heating with a torch gets the rest to deflagrate.

[Edited on 29-1-2012 by freedompyro]

freedompyro - 28-1-2012 at 21:21

Confirmed that this synthesis is correct. Plate dent tests are exactly twice as deep as with the 1.2-2 synthesis as with the powerlabs/megalomania synth with everything else done identically. Also, the coloration wasn't quite correct with the 1-1 synthesis.

I agree with the thread author... Very weak primary. Only suitable for the initiation of something like MHN. Without metal confinement you have a hell of a time getting it to go high order without flash initiation.

I am trying to convert that synthesis for Pb3O4 from PbO... With my bad chemistry skills... Lets see what I come up with a quick approximation!
PbO = 223.20 g/mol x 3 = 669...
Pb3O4 = 685.6 g/mol

Looks like the extra oxygen takes up some weight. 685.6/669 = 1.0248. Multiply that times 1.2.. = 1.2297. Approximately 1.3g Pb3O4 is required? That correct? :D

[Edited on 29-1-2012 by freedompyro]

quicksilver - 29-1-2012 at 08:49

Quote: Originally posted by freedompyro  
No anti-acid. This is a scenario of picrate salts catalyzing the breakdown of nitrated materials rendering them storage unstable.

I just attempted to synthesize lead picrate with 10g 95% Ethanol and 1.2g of Pb3O4 and then a second synthesis with 1.2g PbO.

The Pb304 synthesis failed for some reason... The resulting product is still red. The issue may be that ethanol does not work with Pb304 or that the product was not heated for long enough.

The Lead Picrate from the PbO synthesis won't go high order when initiated by flash... Are you guys sure about the 1.2g PbO? Both megalomania and powerlabs say 1-1 ratio of picric acid to PbO... It won't sustain deflagration either. It just melts and goes POP with a small flame then goes out before it all is burned. Further heating with a torch gets the rest to deflagrate.

[Edited on 29-1-2012 by freedompyro]



This is the old "military" synthesis for normal lead picrate and it really is a poor synthesis. Many people have attempted it because it was commonly seen in a military technical manual.

Do a SEARCH for "basic lead picrate" and you will find a synthesis that yields a product. Normal lead picrate can be synthesized as well.

Storage conditions for long term shelf life are somewhat opposite to stimulus conditions for initiation. You must remove heat, impact, friction, impact, exposure to oxygen & UV. The most frequent and sound approach is to re-crystallize at least twice; this starts you out with minimal contaminants. In some conditions cold (substantially lower than room temp) is very helpful. The deprivation of oxygen is one reason why some materials are stored with a solvent.
Nitric esters however demand purity. Therefore the synthesis must begin properly and carefully for any storage issues to have effect.

freedompyro - 29-1-2012 at 13:05

Thanks a lot quicksilver. Yea, this synthesis is a little sketchy and it's VERY hard to nearly impossible to purify in my experience. But, I did discover the picrate salts are far too insensitive to be used for noisemakers. The silver salts and red phosphorous are the way to go. Silver is getting expensive nowadays...

Here is where I found the basic synthesis if anyone needs it.
https://www.sciencemadness.org/whisper/viewthread.php?tid=50...

Need to make some lead nitrate...

It's kind of hilarious. I have lead oxide, lead tetraoxide, and no plain lead for dissolving into HNO3... Sheesh! My lead monoxide was even made from reducing lead tetraoxide with heat.

[Edited on 29-1-2012 by freedompyro]

quicksilver - 30-1-2012 at 15:41

Quote: Originally posted by freedompyro  
Thanks a lot quicksilver. Yea, this synthesis is a little sketchy and it's VERY hard to nearly impossible to purify in my experience. But, I did discover the picrate salts are far too insensitive to be used for noisemakers. The silver salts and red phosphorous are the way to go. Silver is getting expensive nowadays...

Here is where I found the basic synthesis if anyone needs it.
https://www.sciencemadness.org/whisper/viewthread.php?tid=50...

Need to make some lead nitrate...

It's kind of hilarious. I have lead oxide, lead tetraoxide, and no plain lead for dissolving into HNO3... Sheesh! My lead monoxide was even made from reducing lead tetraoxide with heat.

[Edited on 29-1-2012 by freedompyro]



You're not stuck because if you don't want a large amount You may be able to work that out in several ways. You'll need common HNO3 - Check out:
http://www.sciencemadness.org/talk/viewthread.php?tid=9495#p...

OR.....you can get into some fun stuff with experimentation because I believe it Pb(NO3) may be formed by electrolytic means. If you only want about 250 grams, you won't have too much trouble.

A source for lead can be tough in some areas. Environmental issues have made many sources tough to get a pure element...however some fishing weights may be pure. Many sources have some antimony but are convenient size for dissolving in acid (#8 shot from shot-shells). Some hardware stores have near pure for roof flashing. Old automobile batteries have two lugs that may be pure (take them off with care or drain the battery - THEN use the hammer).

Search "PbNO3" or similar..... I do remember a Hg nitrate to oxide: perhaps there's a oxide to nitrate w/ Pb that's workable. If you have acid, you'll have no trouble w/ a small amount. You won't need much. I know the electrolytic thread may be a fun experiment.

freedompyro - 30-1-2012 at 22:18

I just reduced lead tetraoxide with heat to lead oxide. I then added 25g of my high concentration HNO3 to 75g H2O, and then added 25g PbO. The solution was then boiled off and the Lead Nitrate collected. Note: All of the PbO dissolved and the solution turned clear during heating with a little mixing.

I my yield was eight grams with the Basic Lead Picrate synthesis. Half a gram or so was just left stuck to the glassware and washed off with H2O then H2SO4 and Acetone. Kind of bizarre how the picric acid/NaOH solution is bright orange to red. The resulting powder appeared to be around 400 mesh with possibly dust as small as 600 mesh. Ignore the small stuck together chunks. That occurred during drying. It was dried for merely 20 minutes at 103C.


At first it showed promise of having superior initiatory properties. When 300mg was ignited it would deflagrate with enough violence to make a pop sound. However, it proved to be even harder to DDT when consolidated and compressed. It is conclusive that lead picrate needs metal confinement to reliably DDT.

Perhaps with less agitation crystals of a better sensitivity and acceptable stability could be attained. I'm not quite sure what an acceptable largest crystal size is for lead picrate though. Perhaps it could be wet granulated and dried with 4% of a pyrotechnic binder and that would give a powder with easier DDT but lower VoD.

If lead picrate is not soluble in alcohol a alcohol based binder would make things simpler.

[Edited on 31-1-2012 by freedompyro]

quicksilver - 31-1-2012 at 15:06

There was a discussion on Basic lead picrate some time back and try as I might, I couldn't find it. The material is "demanding" (similar to lead styphnate / styphnic acid) in that slight alterations in temp, scale, & purity levels affect the final material. I know we have the thread however. Check threads for 04-06 year dates It may have started thereabouts (old thread perhaps).
There are some synthesis that don't do well scaling up or down - or that are very sensitive to appropriate Ph levels. I don't want to get off track here but a microscope a very fine tool for determining how you final product is doing. When I explored picrate salts, the most energetic had finely delineated crystalline formation.
Lead picrate is not a great initiator - but you can get some that is substantially more energetic than others. This is a VERY good example of working with a few methods and the needs to keep notes. I found SOME stuff. But I would have to re0-type the individual successes and failures.


11/04

Lead Picrate. 2,4,6-Trinitro-lead-phenolate basic
Molecular weight: 452.303


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. Check structure: broken crystals appeared well formed but easily shaved in bulking intimate contact.
80 C -appears to be the "magic temp number". {end} Always do your math first: it will make or break a synthesis & can be a safety factor in some instances.
Check stoichiometry in both normal and basic is critical: not a "fast" synthesis if you want to determine if you product is a di-basic lead picrate. The above was an experiment note but it yielded something of note-worthy value because when I have some significant issue I write in that it "appears to have 'low stimulus threshold'" or was a "poor product energy as compared to....". Always check math first: then compare it to a source you believe to be quality (like PATR). but "little things" can mean a great deal. With styphnate salts you can change the crystal shape in it's final portion of the synthesis from broken polygonal to cuboid (in the presence of graphite if I am correct). That's quite unique. It may also be accomplished with a picrate. I'm confident about the 80 C temp but the other material is simply notes. Let's say that the above is a productive lab. Ph will be very significant so if you need a 4% sodium hydroxide solution; that should be a #1 priority. #2 should be keeping track of temp, 3rd should be maintaining scale and 15gr in 600ml hopefully is as exact as possible. If you have doubts about the purity of your TNP or whether it may contain DNP they will both create picrate salts....But they may require more exposure time. This is why notes become SO valuable over time as you may discover some materials have 3 very significant variables while others may have 4 or more. If time issues are a serious priority you won't often hear expression like "one hour", you'll read, 50 minutes with no additional heat exposure until solution solids have altered; approx on hour / or until below 35 C.

There is a great deal to discover with energetic heavy metal salts. They can be altered in physical crystal make-up, they can shed light on strong lab technique. & they can be simple to synthesize. However they can be somewhat misleading. If the experiment yielded particulate instead of well formed crystal, the level of sensitivity & speed may be lowered. Differing metals can have decidedly different initiation thresholds (Cu, Hg, Ag, & Pb -being classics). If you feel comfortable with Picrates, there is a great deal to learn from them. but whenever you are working with an unknown scale down the experiment.

____________edit:
Hey, I drank a lot of coffee when I wrote that :D but is the paper brown also? Was the product as dark as it appeared?
Did it precipitate as a granular material or was there some crystalline element to it?


[Edited on 9-2-2012 by quicksilver]

freedompyro - 12-2-2012 at 00:17

Quote: Originally posted by quicksilver  

Hey, I drank a lot of coffee when I wrote that :D but is the paper brown also? Was the product as dark as it appeared?
Did it precipitate as a granular material or was there some crystalline element to it?


[Edited on 9-2-2012 by quicksilver]


Sorry, the light sucks royally... That was a video camera frame also and it didn't have a light mode for "incandescent halfway across the room". LoL! The paper was pure white. It was pretty dark... About 1/3rd less dark than it appears in that picture though.

It precipitated as a purely granular material with zero sign of crystals at all. I had used too much agitation for safety reasons and addition was completed too fast at merely 30 minutes.

In my opinion it may be possible to improve it's properties to a primary by granulating it with a binder... The way it was it's behavior was of a secondary and could not be initiated high order by fuse even in standard metal tubing at any density in 1g amounts... Ill leave someone else to test granulation. I may work on LP again next year when I get free time.

[Edited on 12-2-2012 by freedompyro]

quicksilver - 12-2-2012 at 07:42

My experience with picrates was interesting even though they are somewhat weak, they can be altered. That's about as dark as I have seen. Did it reflect light via crystalline planes?
I have experimented with microscope-digital cameras and been disappointed twice. I may spend some money to get a decent one because Microscopy has been a 'side-hobby" almost all my life and I still have some decent ones and (IMO) some pretty fine sample slides.

freedompyro - 12-2-2012 at 18:20

Not in the least bit reflective in any way I assure you. Not one glint!

quicksilver - 13-2-2012 at 08:55

Well, the only sample I worked with that had any significant energy to it was a basic lead picrate that set up as relativity tough "dark orange" polygons & the variable that MAY have made a difference was the duration of temp (in some thread I have a picture but no magnification: good color however. Most often the synthesis above is followed with a full hour at temperature but it MAY have been cutting that shorter and allowing the solution to come to room temp through an hour made a slight difference (cutting the heat at 40-50min). And realistically, it was not very energetic. I doubt that 0.5 could function as a burst for a little shell. Interestingly I have seen Pb Picrate used as a "bulking agent" in some primer compositions but could find no method to determine if it had a flame spit upon det. like Pb styphnate does.
I had considered other heavy metals such as mercury but could find no literature.

[Edited on 13-2-2012 by quicksilver]

otonel - 21-9-2014 at 08:03

I have a question: if I have tetryl (C7H5N5O8) and lead oxide can make lead picrate using that chemicals?

Hennig Brand - 24-10-2014 at 15:29

I think there are much better uses for tetryl even if it could work.

I noticed that the old military improvised lead picrate synthesis calls for nearly equal molar amounts of picric acid and lead oxide. If the reaction is taken to completion there would be one mole of lead for each mole of picric acid reacted. Basic lead picrate requires one mole of lead per mole of picric acid. Normal lead picrate requires one molecule of lead for two molecules of picric acid (from what I understand). If the product isn't basic lead picrate then what is it? Lead picrate can form several basic salts, according to Matyas.

I did the following only because I have never tried making lead picrate using lead oxide. Lead monoxide has poor solubility in water and methanol and its reaction with picric acid is slow. I tried the reaction with picric acid and lead monoxide, first in water, which even with a two hour long reaction time at boiling water temperature resulted in a partial reaction. The volume of water was kept to a minimum, a little makeup water was added from time to time during the reaction and magnetic stirring was used. I dried the solids and then added methanol and tried again. The mixture was boiled under partial reflux with magnetic stirring. A small amount of methanol escaped as vapor during the reaction. After 1.5 hours the methanol had boiled down nearly completely at which point the beaker was taken off heat and the reaction products allowed to dry almost completely. The reaction this time appeared to be basically complete, but I am unconvinced of this. The more soluble lead salts are much easier to react with picric acid.

The last 10 or 15 minutes of the reaction a darker orange color was starting to develop, but on drying the lead picrate still looks very yellow.

Lead Picrate from Lead Monoxide and Picric Acid.jpg - 339kB


[Edited on 25-10-2014 by Hennig Brand]

Mush - 7-9-2015 at 11:04

Complex salts of basic lead picrate
US 3293091 A

Basic lead double salts of picric acid and method of preparing such salts
US 3262956 A

Complex crystalline picrate explosive containing entrapped amounts of lead azide
US 3431156 A

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