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Author: Subject: Picric acid: different instructions
kABOOM!
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[*] posted on 27-12-2005 at 20:39
quince...show a little class!


WTF, quince! What did I do to piss you off!? Sorry, I guess I need more information...I'll provide it--- provided that you get off my back pal. Thanks.

I used the following chemicals in my procedure:
25g ASA (purifyed via Ethanol)
35ml H2SO4 (96%)
50ml HNO3 (95% estimated- home brewed)

I added the ASA to 35ml of H2SO4 in a pyrex flask and allowed the temperature to rise using a hot water bath. The temperature was kept at 90 C for 1 hr 10 minutes. The ASA-sulphuric acid mixture was completely dark by this point- and sulphonated. I then chilled the liquid to -1C in the freezer for 35 minutes. I even packed a shallow water-bath which help keep the temperature down substantily then I added the 50ml of HN03. The temperature gradually rose....a few red NOx fumes evolved and I left the mixture to get up to room temperature... then I put the beaker back into a hot water bath. The temperature of the water never got above 70C ...lots of red NOx fumes evolving by this point. The digital thermometer gave me a reading of 65.5C for the water bath-- kept in for 15 minutes. The end product was creamy yellow, and filtered using distilled water and kept cool for several hours.

[Edited on 28-12-2005 by kABOOM!]
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[*] posted on 27-12-2005 at 23:23


Quote:
Originally posted by chemoleo

Hey chameleon, you're letting all those stars besides your name get to your head. Or maybe it's all the fumes from your chemistry stash.




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[*] posted on 27-12-2005 at 23:30


Stop being a petulant dickhead Quince. Cheap provocations won't get you anywhere.

You are off-topic for the last 3 posts, and you are flaming quite unnecessarily so, particulary in light of the fact that you are not quite in the position to flame, looking at your previous record.

Now STFU and CONTRIBUTE something WORTHWHILE rather than random flaming just to pat your ego.


[Edited on 28-12-2005 by chemoleo]




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[*] posted on 27-12-2005 at 23:54


Quote:
Originally posted by Quince
What the fuck does this mean? Ever heard of numbers, measurements? "say 65 degrees"?! Did you even use a thermometer, or just stuck your finger in and it seemed warmer than your mother's twat? What made you choose that particular temperature? Why not 50, or 80? No, wait, let me guess: it just 'felt right'. For fuck's sake, I thought this forum was about chemistry, not fucking medieval alchemy! This forum is being taken over by the k3wls, it would seem! Hey, I've got an idea, let's just start mixing up random shit in proportions determined by the dice roll/cards/stars!

So, your mood shows as awesome, eh? Is that due to the holidays, or did you taste one too many of your witch's brews?

Any moderator care to check the IP of this tool, to see if it's another incarnation of Hideki, or just a cretinous copycat?

[Edited on 27-12-2005 by Quince]


having a bad day eh...
i suggest a good visit to gym, hitting the sack, or shooting some mice and finish em with a bat..
the net doesn't work for cooling off, and u know, u don't want your hand to shake when u are working with those substances, unless u have a few spare fingers.
Goodluck

[Edited on 28/12/2005 by Nevermore]
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[*] posted on 28-12-2005 at 00:22


I'm no longer working with those substances; my pyromaniac's days are past. The only explanation I have for the continued experimentation with explosives by people on this forum is that they are compensating for being cursed with a smaller-than average manhood. For the asians like Hideki, though, that should be expected, so there must be another explanation for that particular individual. Happy holidays.

[Edited on 28-12-2005 by Quince]




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[*] posted on 28-12-2005 at 09:25


You'd think that someone with that many posts would know better and that sanctioning would only be required for n00bies...

Apparently not. You've gotten enough warnings quincy, you're suspended for 14 days. Go shoot your guns and come back when you've blown off some steam.

[Edited on 28-12-2005 by vulture]




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[*] posted on 25-9-2006 at 09:57


*BUMP*

sorry for that, but I AM interested, and although it`s taken me the best part of an aftrenoon Ive read all the posts in here, Rosco I`m Impressed!:o

I`m trying to do Similar but on a Micro scale with only single figure Gram quantities.
thus far I crushed 16 x 300mg aspirins, dissolved the lot in 100% pure Etoh, filtered and evaped.
put that in a boiling tube and added 20ml of 98% sulphuric.
at this point it warmed and went yellow orange and the powder turned gel like and slowly mixed into the acid.
upon careful heating I watched color changed as stated in this thread and stopped heating at the "Black" color.
(although not technicaly Black) there were a few White fumes emited also and a distinct Vinigar smell.
upon cooling however, the Mixture has solidified, and it`s not even down to room temp yet!

What have I done wrong?

or is it another case of YT makes yet MORE Black useless junk when trying to do Orgo chem :(

I`ll cap this tube and await a response before continuing further.

I`ll also point out that I only wish miligram quantities from this just to Look at, I have No interest in boom booms!

EDIT: I also plan on using 70% nitric acid as the O2N donor (if that makes any difference?).


[Edited on 25-9-2006 by YT2095]




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[*] posted on 25-9-2006 at 11:14


You haven't done anything wrong at all by having the
disulfonation product set up solid on cooling .....that is
exactly what it normally does . It will melt again when
you reheat it to the temperature where you will begin the nitration .

To keep the mixture more liquid you can use more sulfuric acid .

The nitration should work fine using 70% nitric , although
I haven't worked out the exact times and temps , and the
reaction may progress differently .

The nitration mixture will still require heating at least to boiling water bath temperatures and holding there for some time towards completion of the nitration to produce a most completely nitrated product .

BTW you need to do the nitration in a flask to allow for
some expansion room for the foaming which will occur .

[Edited on 25-9-2006 by Rosco Bodine]
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[*] posted on 25-9-2006 at 11:21


well from I`ve learned from your posts thus far the Mono Nitration part may take place (and preffered if) it`s at a lower temp.

I`ll use a Hypo to deliver the nitric anyway, that way I can guage the exact amounts and literaly do drop at a time.

for now I`ll leave this as a solid until I get more time during the day tomorrow, you said also that the residual acetic may not present a problem also, and so I`ll leave it capped too.

thnx for the info :)




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[*] posted on 25-9-2006 at 12:46


Concerning theory and experiment .....

One thing you should consider doing is using solid nitrate
for the first third to one half of the nitration , since
that is so straightforward and can be done at a high
initial temperature with a good nitration rate .
And then use your 70% HNO3 for the remainder of
the nitration , where it would probably be of benefit
for not causing any further loading of the mixture with
solid byproducts , as would occur where the entire nitration is done using a solid nitrate .

Such a scheme could perhaps exploit the desirable
property of the solid nitrate in the first third or half
of the nitration where it works best , and would conserve
your 70% HNO3 for that later stage in the nitration where
it would possibly have advantage . However it is
not assured that the reaction itself will behave in accordance with the expectation , as it may or may not .

Also , in these sulfonation mixtures where the water content is low and the H2SO4 content high , in an undiluted sulfonation mixture , there is not really any distinct three stage reaction for the nitration products ....indeed there is some end product appearing already in the nitration mixture early during the nitration , even though the lower nitration products predominate , there is an overlapping of the
nitration products stages which is present throughout the process . So , even though only one third of the total nitrating agent is added , the conversion to mononitrated
product is not complete , but the mixture contains some
of the unreacted sulphonate , and all three nitration products , but the mononitrate
* theoretically * should predominate . What is the actuality on the proportions and the progress of this sort of nitration mixture is unknown . So to get fully past the mononitration stage , could require as much as half of the nitrating agent to have been added and reacted , since not all of the first third was reacting in a way to produce the mononitrate , but was diverted to formation of some of the dinitrated and trinitrated products .

[Edited on 25-9-2006 by Rosco Bodine]
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[*] posted on 26-9-2006 at 06:32


One of the most valuable things I have picked up from you was temp control issues and proportions. the 1 to 4 ratio of H2SO4 & ASA (and the solid nitrate 1.8: 1) have seen me through some pretty fun experiments.In fact I was suprised to see this post up as I just got done following a solid nitrate / ASA nitration of 100 grams. You once said something about coping with foam that is a good deal.....takes a lot patients to SLOW down the introduction of a solid nitrate when the experiment will certainly take you the whole day...... :D It is pretty nice when one emulates an experiemnt and gets the same results in terms of yield % and product quality!



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[*] posted on 26-9-2006 at 08:25


Yeah it is a very gradual process of nitration which seems to resolutely resist efforts at speeding it up ,
which always seems to bring complications with foaming
and diminished yields , in my experience anyway .

The slow pace is one of the things I thought could be
addressed by using solid nitrate for the first half of the nitration , and then using 68-70% HNO3 for the second half .....hoping that the total time could be reduced by
a third to a half of what is required when only the solid nitrate is used .

The conversion of aspirin to picric acid in a most efficient
and optimized manner is a desirable synthesis to have
all the details established . Picric acid and several derivatives of it are for many reasons
" practical energetic materials 101 " , even though
the literature seems to focus greater attention on other materials , which tends to deemphasize the true significance and usefulness of picric acid . Because it
can be made from many different starting materials ,
and is so useful both directly , and as an intermediate for
other useful materials , it is and should remain a keen
interest for experimentation . Where it is written otherwise that picric acid is somehow archaic or has
no particlar usefulness or versatility , are words you can
attribute to someone who doesn't know what they are talking about .
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[*] posted on 26-9-2006 at 09:12


well, I`ve completed the Next step, over the space of 30 mins the KNO3 was added spatula at a time.
this was done outdoors in a 250ml conical flask as you recommended, at 1`st there was little i the way of NO2 but white choking fumes instead, the NO2 didn`t really happen until about half way, I was trying to keep the heat up as you can imagine about 25ml in a large flask outside on a cool still day isn`t easy.
eventualy I was down to half a spatula at a time but faster feed until there was no visible reaction even with movement of the liquid.
the color was orange and perfectly transparent.
this liquid got thinker and crystals started to form up the flask, upon gentle heating LOADS of NO2 came away and everything dissolved again, the color is quite a bit lighter now and it`s also lke thick honey as it`s cooling and there are 2 crystals forming, and many less than hair thickness making "cobweb" paterns up the side of the flask, these are Lemon yellow, and LOOK like the product.

I`ll cease the reaction at this point now and let it cool until I get further advice from you Rosco.
I didn`t do the HNO3 70% idea in the end, I stuck to the "tried and tested" method for a 1`st go.

I know at Some point I`ll have to shift all the K2SO4 out the thing, and being such a tiny microscale synth, I daren`t crash in ice water else risk loosing the lot.




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[*] posted on 26-9-2006 at 09:45


YT,
The first time I did this synth was also with 1 pk aspirin (24@300mg). I don't have any refferences handy, but it was something like 8gm ASA to start with. This was then sulphonated with boiled battery acid, before being nitrated with.. wait for it .. (I'm a bit embarrased about this one) Pottasium Nitrate that was extracted from comercial black powder :o - I know, I know - but it was the first nitrate source I had.

Anyway.. The synth was carried out and was simply scaled down. I'm sure I dont, but IIRC it was about 100gms of ice and water that I crashed it in. Solubility's somewhere in the order of 2 or 3 gms per L (or was that per 100ml??)

I ended up with in the order of 4-5 gms of picric. Far from Ideal, but acceptable given the care (or lack therof ) exercised throughout

This was then succesfully used to make lead picrate - both normal and basic. Some went into a comp det and the remainder functioned as an extremely loud whistle - which, I er in-tended. Yeah, that's right - I wasn't trying to make a det with the powder pressed too tightly at all.. NOoooo. not at all. ;)

Too lazy to look it up, what about K2SO4's solubility in EtOH? If you're going to make PbPicrate, then there's the first step done too.
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[*] posted on 26-9-2006 at 09:51


A thermometer is helpful for this reaction if you are
trying to get good efficiency , because you are going to have to run it pretty hot and the thermometer will allow you to track what is going on in the mixture .

If you are using KNO3 , the K bisulfate byproduct is so much less soluble than the sodium analogue that you should be using more sulfuric acid , perhaps 5.5 to 6 ml of H2SO4 per gram of ASA . I'm not sure about the best ratio for KNO3 because it has been a long time since I used the KNO3 , switching to NaNO3 early on because of
the reduced quantity of H2SO4 required . I do recall that KNO3 did work well , it was just not as efficient in the utilization of acid .

That old thread

https://sciencemadness.org/talk/viewthread.php?tid=4457&...

See near the end of the page my post

" picric acid from ASA , NaNO3 and 92% H2SO4 "

It contains some details that ordenblitz was duplicating here in this thread . Maybe the process for NaNO3 can be interpolated for KNO3 . IIRC the KNO3 process also
could run at a bit lower temperature , maybe by 10C or so . Experiments with NH4NO3 solution were not done
on ASA , but observations on its use in other nitrations
indicated that it favored an even higher temperature for being effective particularly in the final stage of nitration .
It became clear that water content of the nitration mixture , the type of nitrate being used , and the ratio
of the acid mixture to the quantity of picric acid being attempted , time of reaction , and temperature range
for the reaction are all together interrelated factors which
affect the process . Change one thing and it changes everything else to some extent .
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[*] posted on 26-9-2006 at 10:10


well Happily (I think) the liquid mass has now crystalised from the edges inwards with fine yellow crystals in an Orange syrup.

there`s no Red globs or sludge as has been reported by some in this thread, so I`m pleased with it thus far.

I`m in 2 minds now if to re-heat and crash onto ice and a little water, or Add ice water, I think the former would be safest as water to acid is Never good.
eitherway, it will be the bare Minimum of H2O irrespective of phase, and then put into the fridge, liquid poured off next day.

then do the same again with BOILING water at a minimum to dissolve all with a drop of HCl added, and then lagged to cool Very slowly.

pour off the liquid once more and then follow the purification proceedure as also outlined in this thread.

if anyone can see a flaw or a Better way to get my product out Please let me know!
that`s the reason I`m doing this single step at a time :)

but rem, I only started with 4g of Pure ASA!

EDIT: ok, I decided to "Wing it" after reading the link you provided, and added the cold water to the inside wall of the flask, and yes, there was heating and NO2 liberated also.
I took the water vol up to the 130ml region and kept the lot moving constantly, eventualy All the solid mass broke up and the color is now All a lemon yellow with white to yellow tiny crstals floating about.
Most stay on the bottom but there`s also about 10% on the top too and swishing makes them stick to the side walls :(
satisfied that no solid clumps exist, it`s now in the fridge to stay overnight.
I`ll decant where possible, if not I`ll just filter out and give a cold water rinse.
and then follow the rest of your proceedure in that link but with the HCl addition.


Interesting that you mentioned about picric being a lost art and Archaic, if you actualy knew what my plans were for it, you`de think I was archaic and out of the Ark! :o

[Edited on 26-9-2006 by YT2095]




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[*] posted on 27-9-2006 at 04:32


ok, it`s all done, I have roughly Twice the volume of picric acid as the starting crushed asa (a pleasant surprise).
it`s been washed twice, filtered with a rinse and is now in plain water with a few drops of 38% HCl and back in my original boiling tube with a cork in it (I don`t want any to dry!)
I considered re-crystalising this but I don`t like the idea of large crystals of this stuff, so a fine sulpher like powder is ideal, especialy for my application as a Wool Dye.

I would like to know what the Ideal way to store this stuff is, under water is a given as is non metalic, but what sort of container ?
I`ve heard of this stuff crystalising around bottle stoppers and exploding when someone tried to open it, does it have vapor pressure issues like Iodine for instance?




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[*] posted on 27-9-2006 at 06:32


Picric acid is reasonably safe to store dry . It has no volatility at ordinary temperatures . A pill bottle
with a plastic cap is fine for storage .

It is such a powerful yellow dye that if one should even glance upon an uncontained sample without wearing safety glasses , that not only the researcher will be permanently dyed bright yellow , beginning with the white of the eye and permeating to even the soles of the feet .....but also ones children shall have the complexion of canaries even to the third generation ;)
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[*] posted on 27-9-2006 at 06:39


There are a lot of idiocyncracies that fly by and are not noticed. A heavy stir-bar....a strong vortex, the use of NaNO3 rather than KNO3, (which solid nitrate to use is a whole thread in itself) a final inclution of HNO3 to boost the fluid volume and maintain the "freshness" of the nitration, the recording and attention to temp-altering the additions of solid nitrate to temp changes....these issues can help keep foam down and maintain a fine product time after time. I said this before; I keep a Hell of a lot of the things people write, I also maintain a lengthy written record myself. I worked on a 100 gram ASA synth and knew I was going to get very sharply deliniated, beautful crystals of reagent-grade TNP.

[img]null[/img]

[Edited on 27-9-2006 by quicksilver]

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[*] posted on 27-9-2006 at 07:15


Nice Pic!

although it maybe the ambient light, but mine looks a little lighter yellow than that, but the liquid (dissolve PA in H2O) is insanely yellow, I`ve already dyed a strip of fleece in the leftovers (filter paper and washing sols), I think I`ll not dry this product though, I`m happy with it left in the bottom of the boiling tube under a layer of water, I used a tiny drop of Ammonia in the water to make sure all stronger acid traces are gone, and if some turned to Ammonium Picrate then that`s just fine too, in fact I considered doing that to the entire batch just for stability reasons.
Wool contains Amines though and so I decided against it as that`s probably what the PA reacts and bonds to in the wool.

I`m happy with my product now, Thank you All very much each and esp You Rosco, without your posts in this thread I feel that things may have turned out somewhat differently than they have!
more than likely yet another case of YT makes some More useless black organic junk.

Cheerz each, I`m satisfied now :)

[Edited on 27-9-2006 by YT2095]




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[*] posted on 27-9-2006 at 07:31


Quote:
Originally posted by quicksilver
There are a lot of idiocyncracies that fly by and are not noticed. A heavy stir-bar....a strong vortex, the use of NaNO3 rather than KNO3, (which solid nitrate to use is a whole thread in itself) a final inclution of HNO3 to boost the fluid volume and maintain the "freshness" of the nitration, the recording and attention to temp-altering the additions of solid nitrate to temp changes....these issues can help keep foam down and maintain a fine product time after time. I said this before; I keep a Hell of a lot of the things people write, I also maintain a lengthy written record myself. I worked on a 100 gram ASA synth and knew I was going to get very sharply deliniated, beautful crystals of reagent-grade TNP.


Yeah there are still yet to be worked out details for
finessing and tweaking the conversion of ASA to
picric acid , depending upon the variables encountered
with different approaches , to arrive at proven methods
that would be optimized . These variations which
are specific to the use of ASA as the precursor could
be the basis for a whole range of experiments which
could reveal exactly what combinations and proportions
work best .

It is good to have easy access by relatively simple synthesis for a valuable reagent like picric acid ,
eliminating dependance on some commercial supplier
whose pricing or other interest may be undesired .
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[*] posted on 27-9-2006 at 22:11


Optimizing these labs is truely a "Labour of Hercules" as it seems that when one begins to really look at the variables....they just get longer and longer! And anoting the dynamics of what actually happens when these variables are tweaked gets to be a serious undertaking. I have a lot of fun studying this stuff.
The one synth that I have yet to work with is the catalytic via mercuric nitrate....That is something I would really like to play with. There is something about going back to the very root of benzene that may offer some outstanding elements of study and learning. I actually have some Hg(NO3) reagent but I'm figuring that nitric acid and metalic Hg could do it. (HgNO3 is EXPENSIVE stuff!) The challenge would be finding benzene now-a-days.....
And I am in TOTAL agreement that picric acid IS the most significant energetic material one could synthisize. While lead picrate has been cast as a less effective initiator I have no doubt that it would be just fine for the specific initiation of PA itself. As crude as it seems on the surface, I believe that a lead picrate-picric acid detonator could be opimized for mirroring the initation abilities of a #8 commercial cap. I have no doubt that in crude tests such as a "bent nail test" like that of the U.S B. o M. would yeild results that put it in the ballpark of standard commercial material.
One of the most unique experiments has been that of friction and impact sensitivity of PA. So much has been made of the dangers of dry PA I have found that crystal size, shape, and synthiziation have shown differing results in simple field testing. Friction testing is one of the more difficult to perform with less than professional apperatus. Maintaining accurate weight the test which could be duplicated, it appears Ithat of a block of steel upon another using gravity and angle as a propelling medium. PA appears NOT to be that friction sensitive when compaired to materials like ETN or MHN which seems to be as sensitive as many primaries. Falling hammer impact sensitivy however is very revealing. Showing freshly made, non-shaven crystals of large size to be quite sensitive; especially that of a large rhomboid shape. Cube-like, well compacting crystals are second in line for sensitivity.

[Edited on 28-9-2006 by quicksilver]




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[*] posted on 28-9-2006 at 01:06


To get picric acid to detonate from its derivatives used as an initiator is possible , but lead picrate alone is not going to do the job in any reasonable amount , in an unreenforced detonator anyway . More powerful derivatives like DDNP , or the 4/12 azo-clathrate will do the job , and the basic picrate or one of its multiple salts can be used as a flash igniter . A very storage stable , reliable and powerful detonator can be made where the base charge is picric acid and the initiator and igniter are derivatives . The critical diameter and mass for picric acid is a fair amount larger than for something like PETN ,
so picric acid performs better in larger devices , and requires fairly heavy initiator charges to cause its
complete detonation . But it is sufficiently sensitive
and brisant to be an efficient base charge in a detonator .
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[*] posted on 28-9-2006 at 03:10


Quicksilver,

I second what Rosco says about the basic metal salts of picric acid not being sufficient initiators of Picric acid.

I've done several experments in this regard with basic lead picrate, using even up to 15 grams with out a positive detonation of the picric acid.

However, and I'm frustrated I can't find the source to quote, but I remember distinctly reading that sulfur greatly sensitizes picric acid both to shock and to heat.

It would be great if we could find a suitable sensitizer to make picric acid detonate from basic lead picrate as it is easy and cheap to prepare.

I will try to find my source on this thought of using sulfur to sensitize PA, and better yet in the future I will conduct some tests as to various substances abilities to sensitize picric acid enough to cause it to respond to such things as flash powder and lead picrate.

I think if our goal is to get a salt of picric acid to detonate picric acid, we should not increase the amount of the salt or reenforce the cap more, but rather find a way to sensitize the picric acid to respond to the picrate salt!
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[*] posted on 28-9-2006 at 05:04


IIRC (and I don`t remember the source) but it goes something like the More sensitive the picrate, the less brissant, the opposite applies whereby the least sensitive picrate (ie Ammonium picrate) will be the most brissant/powerfull.

I can`t be sure, but I think as a general rule-of-thumb this applies to Most explosive materials (there are exceptions such as AN).

this isn`t really my area though, so I could well be wrong!




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