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me234
December 16th, 2005, 02:51 AM
Man, finally, I've been wanting to put this up for months.
So anyway, I have this document which sets out the proper way in which a scientific chemistry report should be constructed, and I’m kinda going to follow it, so sections which are normally longwinded will be treated rather rapidly ’cause they’re not why people are reading this article. So here goes:

Introduction

Nickel Hydrazine Nitrate (or “NHN” (1)) has been proposed by both Shunguan et. al. (1) and Chhabra et al. (2) as a potential primary explosive for use in detonators and other explosive devices, and is focused on by Chhabra et. al. as a replacement for Lead Azide to mitigate its less desirable properties, i.e. incompatibility with Cu etc.

NHN is an interesting explosive, especially in terms of a primary explosive, due to its reported low friction and impact sensitivities, coupled with a decent density, and a high VOD (properties will be given later). (1,2)

The aim of this investigation was three fold, firstly, to synthesise NHN and confirm its manufacture; secondly, to evaluate its suitability as a primary; and thirdly, and as always, to screw around with the stuff.

Experimental

A saturated solution of Nickel (II) Nitrate was diluted to roughly twice its volume with 95% ethanol. The stoichiometric amount of hydrazine hydrate was calculated, and a slightly less amount was measured out and diluted to twice its volume with 95% ethanol The ethanolic hydrazine solution was placed on a magnetic stirrer and a stirrer bar was added and the solution was stirred at a medium rate. The ethanolic nickel nitrate solution was added initially on a drop by drop basis until the reaction became familiar and nervousness subsided somewhat. Upon the nickel solution coming no contact with the hydrazine solution a bluish (almost lavender) precipitate was immediately formed (very much instantaneous), this did indeed change to a more purple precipitate upon contact (and thus agitation from this contact) with the stirrer bar.

After a few initial milliliters of nickel solution, the addition rate was increased to a few ml a minute this was slowed a bit when temperature of the reaction mixture was noticed to have increased, to maybe 30/35 degrees Celsius.

Despite increasing the stirring rate of the stirrer bar, it quickly became ineffective as the beaker choked up with the precipitate very quickly

Half way trough the addition of the Ni solution, the beaker was almost completely full with the precipitate, and the beaker contents had to be stirred hard with a glass rod to induce contact between the two solutions. At this point the precipitate was isolated by means of vacuum filtration, and the solids washed with some of the Ni(NO3)2 solution. This turned out to be a mistake, as residual hydrazine solution in the Buchner funnel caused the formation of the precipitate inside the funnel, and also in the collecting flask. It was around this time that it as noticed that the precipitate formed is, in fact, rock hard, and a bitch to break up. So some more of the Ni solution was just added to the filtrate in the collecting flask (until no more precipitate formed, then a small extra was added), and the precipitate was filtered out.

The precipitate was crushed a bit while on the filter paper, and then washed first with the remaining, excess Ni solution then with a 50/50 deionized water / 95 ethanol solution 2 or 3 times (I forget, this was one almost months ago), then twice with straight 95% EtOH (to speed up drying). The dried product, again, rock hard lumps, was powdered fairly fine using a plastic spoon.

Results and Discussion

Yield
I didn’t weigh what I got, but if this isn’t a quantitative yield, then damned if know what is.

FTIR
The resultant product was air dried and was then characterized by FTIR. The resultant spectrum obtained, while not the best ever as the disc was made too concentrated, did contain all the peaks (with minor shifts) mentioned by Chhabra et. al., i.e. 3238 - NH2; 1626 - NH2; 1356 - NO3; 550 - Ni-N peaks (all units are per-centimeters).
Preparation of KBr discs was a nightmare: I really don’t consider compressing a primary explosive to ~10000 tons pressure fun. Of the 4discs I made, 3 of them (all but the most dilute NHN disc) made an audible crack around the 7 ton mark, I don’t know whether this was a couple crystals detonating or what. It might have been this, or it may have been a larger crystal breaking up. I don’t recall seeing any kind of discoloration of the disc afterwards, so I’m going for the large crystal breakup theory.
From this (and from the burn tests) it as concluded that NHN was successfully prepared.
If anyone wants to see the IR spectrum, just let me know and I’ll e-mail it to a couple people.
Also, if anyone here doesn’t have experience with IR spectroscopy and didn’t follow the disc thing, just say so and either I or someone who knows can explain it.

Deflagration
When a small amount of NHN was ignited, by means of the flame from a match, it burned very quickly, and very violently. Larger crystals (maybe 0,1mm) burn with something very close to a white flame, and the fine powder, when spread out, burns too fast over its entire mass to actually notice a flame color. Larger lumps of this stuff tend to fly when ignited, i.e. the first bit ignites, and propels the rest of the lump/crystal while the rest of it burns. In fact, this stuff burns faster than any flash powder I have ever seen, including commercial stuff removed from fireworks (which I only heard about of course and never actually did myself). This stuff would make some awesome firecrackers. Keep reading if you’re concerned about firecrackers made from this stuff detonating.

Detonation
Drinking straws were used in this test, all we 6mm in diameter.
When reading this please bear in mind that I didn’t have a scale for these tests.
A layer of DNB was pressed as hard as possible, by hand, into the bottom of a straw until a 5mm layer was obtained. On top of this was pressed, for Test 1, a 5mm layer of NHN (hand pressed as hard as possible while cringing and wearing goggles, earplugs and gloves), followed by ~10 seconds worth of a KNO3/sugar delay mix. Test 2 had the same thing, but after the 5mm NHN, there was an ~2mm layer of trimeric AP (although the AP was several months old, 5 degree Celsius storage) pressed on top followed by the delay comp. The AP wasn’t pressed as hard as the first two layers, but was pressed almost as hard as I normally press it for use in det.s and this pressure has never failed me for lack of compactness of AP.
Both test 1 and 2 where performed in triplicate. The caps were buried a few cm into some loose dirt, then ignited.
DNB was used because it was the only secondary I had access to at the time.
The results?
Quite disappointing:
The three DNB-NHN caps failed to detonate. In all three cases the delay train successfully ignited the NHN, which then burned fiercely and quickly, causing a whoompf as it deflagrated and very mildly scorched the surface of the DNB. All three caps went low order through the NHN layer.
Test 2: Three caps were tested, the AP layer in each was very close to 2mm long, but that doesn’t men that the precision, with regards to AP weight used, was very good.
2 of the three caps tested didn’t detonate the DNB layer, but they did make an audibly louder whoompf, verging on a pop. The third one however did detonate, no residual DNB could be found. The NHN definitely did something right in that last one.
I suspect what happened was that, for the first three (i.e. Test 1), the NHN merely deflagrated. In Test 2 I suspect that the AP columns of the first2 tests were not big enough to ensure a full deflagration –to-detonation transition for the AP/NHN column.

Table of properties

Table 1: Properties of NHN
Density (1) 2.129 g/ml
Bulk Density (1) 0.85-0.95 g/ml
Oxygen Balance -5.74%
Volume of Explosion Gases (A<100oC / B>100oC) A 321.3 l/Kg
B 803.3 l/Kg
Nitrogen Content 40.%
Heat of Explosion (1) 1014 kcal/Kg
Velocity of Detonation (1) 7000 m/s @ 1.7 g/ml
Explosion Temperature (2) 219oC (heating @ 5oC/min)
Friction Sensitivity(2) 10 N +/- 1 N
Impact Sensitivity (2) 84 cm +/- 2.5 cm (2Kg drop weight)
Incompatibilities (1) Conc. H2SO4; 10% NaOH (mild reaction)

These properties were accumulated from the 2 references given at the end of the report; anything not referenced in Table 1 was calculated by hand (well, by calculator actually).
The sensitivities given are both taken from reference 2:
Impact sensitivity is given for 50% of the samples detonating; Friction sensitivity was found by increasing weights by 2N until 5 consecutive samples didn’t explode (Julius Peter apparatus (2)).
NHN’s incompatibility with 10% NaOH is suggested by Shunguan et. al. (1) as a possible method for disposal of NHN.

Compatibility tests
NHN’s compatibilities were tested by crudely mixing (by the 'diaper' method I think it's called) a small amount of powdered NHN with a small amount of the powdered test substance (or adding 2 drops of any liquid test substance), wrapping this up in newspaper, and leaving in a dark room for several (5) months. Blanks accompanied the test mixtures.
The following substances were tested for compatibility with NHN:

1 - AP
2 - DNB
3 - KNO3
4 - KCLO3
5 - AN
6 - Al powder
7 - NM
8 - NaCLO4
9 - activated C

Test samples, and blanks, were checked up on every month or 2.
Visual inspection was the standard by which any reactions were judged.
In all cases the NHN came through the tests unaffected.

AP: The AP crystals, after 2 months, were huge, some several mm long! After 5 months, no AP remained, NHN was unaffected. Oddly enough, the AP crystals with NHN were consistently smaller than those not in the presence of NHN. I suspect that the NHN provided multiple nucleation sites for condensing AP, allowing for many more, smaller, crystals to form. Besides this, No Observable Reaction.

DNB: Acidic and neutralised DNB was used. No Observable Reaction.

KNO3: No Observable Reaction.

KCLO3: No Observable Reaction.

Ammonium Nitrate: The AN swiftly absorbed atmospheric moisture an dissolved. No Observable Reaction.

Al: No Observable Reaction.

Nitromethane: The NM blank discolored the paper a darkish yellow/orange. The same thing happened to the paper of the test sample, and the NHN was somewhat darkened (it looks the same, but with that “wet hair is darker than dry hair” look).
I don’t know why the NHN turned a darker shade of purple. It could be that whatever the NM did to the paper caused the incorporation of a dark yellow/orange pigment into the NHN, but I doubt it.
Also, the NHN is now small balls instead of fine powder it started off as. These balls also have difficulty igniting, i.e. it takes a while for a flame to ignite them. Perhaps it is that the NHN is still damp with a small amount of NM.

NaCLO4: The crystals behaved the same as the AN did. No Observable reaction.

Carbon: No Observable Reaction.

From these tests I feel confident about NHN being compatible with most everything. I was out of HMTD, so I didn’t try that, but if anyone really wants me to, I suppose I could try that.
Common reducing and oxidising agents seem to have no affect on NHN. Like HMTD, I was out of KMnO4, so that was not tested. Again, if anyone really wants to see those results, I’m sure I could try it.
Shunguan et. al. (1) report “negligible reactivity” with Cu, Al, Fe and stainless steel over 8 years.

Conclusion
NHN has potential, I’ll give it that. But as a primary, unless it’s used in exploding bridgewire devices, it’s used in kinda large amounts, or it’s used mixed with other primaries, then wouldn’t recommend using NHN for a primary. However, as a base charge, it could be very effective, especially with a very decent density, and a 7000m/s VOD!
Overall, NHN is very easy to make, and quiet fun to use. However I’m quite paranoid about poisoning myself, so I just take some vitamin C after working with anything hydrazine based.

Future projects
Any suggestions?
I‘m thinking NHN putty (NHN/NC). Maybe with something added to ensure the NHN goes high order. Any ideas about this? I think I need something that has a quick deflagration-to-detonation rate. Come on people help me out here.
Any other ideas about what people would like to see done with this stuff are more than welcome. If the idea you put forward is just to screw around, fair enough, but please say so. If there are any scientific minded tests wanted, post them or PM me, but let me know what type of results you want to see, I’d hate to use up what I have and I didn’t even get you what you needed. Proper tests, if I can do them, will most likely (not necessarily) take preference over screw-around tests. That being said, I'm looking for a way to screw around with this shit, I really do want to do some plain old FUN stuff here.
So please, any interesting ideas about what I can do with the rest of this stuff, go ahead.

References

1 – Shunguan Z, Youchen , Wenyl Z, Jingan M, 1997, “Evaluation of a New Explosive: Nickel Hydrazine Nitrate (NHN) Complex”, Propellants, Explosives, Pyrotechnics, 22,pg 317-320

2 – Chhabra J,TalawarM, Makashir P, Athana S, Singh H, 2003, “Synthesis Characterization and Thermal Studies of (Ni/Co) Metal Salts of Hydrazine: Potential Initiatory Compounds”, Journal Of Hazardous Materials , 99(3), pg 225-239

If anyone wants me to e-mail them a copy of the IR spectrum, I'd be happy to.
And also, if anyone wants me to explain my referencing technique, again, no problems, just let me know.
Keep the ideas coming.

quicksilver
December 16th, 2005, 10:47 AM
Thank you for posting and working on what seems a pretty involved project. I apprieciate the way you provided a readable format.

When I think of hydrazine primaries I too think of poison. Frankly, it scares the crap out of me as I just heard of a family friend who was a research chemist passing away at 48yrs old from liver failure (and he didn't drink)....but aside from all that has any work alone the same lines been done with nickle azide? I am not sure of this but I think one of the references you sighted (Athana S, Singh ?) did some work with azides.

Anyway; nice stuff, I kept it as a text file for future reference. - well done.

hereno
January 7th, 2006, 04:08 AM
me243, Why did you use alcoholic solution? The reference (1) shows its solubility to be very low in water, less then EtOH. I think thats the synth posted on scimadness right? but surely EtOH isn't needed, unless you want to use it to wash the precip for shorter drying times.

Can you attach the Chhabra reference? (use rapidshare or something, it'll never get approved if attached here). I have the first reference from sciencemadness but not the second.

simply RED
January 9th, 2006, 10:50 AM
These forum articles are becoming better than many such - published in the dusty academic magazines :) .

me234
January 30th, 2006, 01:50 AM
Hereno: I used the alcoholic soln. because I was basically just copying the sciencemadness synth that I read (I can't remember who posted it, AXT maybe, but thanks to them anyway).
The fact that it also aids drying, as you correctly though, was a bonus (I've always hated waiting for stuff to dry). The ethanol really did help me dry it nice and quick. Another bonus is that it helps dilute the reaction mixture without using water (drying aspect again), cause let me tell you, huge yield, HUGE, it was fantastic. The beaker got so bloody full it seriously was a problem trying to get the two soln.s to mix, especially since the ppt. was fairly hard and had to be a bit broken up before they would mix thoroughly.

I don't have that Chhabra article one me now, but I'll e-mail it to you if you want when I next stop in (might be a week or so unfortunately). Just post or PM me your e-mail address and I'll get it off as soon as I can.

Quicksilver: Hydrazine scares the shit out of me too! A couple of times after working with the NHN for any longish time (10-20 minutes or so) I get a headache, this is then followed closely by a sneaking suspicion about where I got it from. But I googled hydrazine as a poison, and after a couple other searches I saw a site that says Vitamin C is supposed to help with hydrazine poisoning. So now every time I work with it, I just pop a couple pills, and the headache actually leaves in short order.

me234
February 23rd, 2006, 09:23 AM
Hereno, I was just going to PM you the address for the article, but I figure everyone should have access to it. It's a bio based website (of all things) full of journal articles. It asked me to register before I could get the whole thing, but it was free with no waiting period (i.e. ~ 30 seconds):

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TGF-48B01DH-1&_coverDate=05%2F30%2F2003&_alid=369693422&_rdoc=1&_fmt=&_orig=search&_qd=1&_cdi=5253&_sort=d&view=c&_acct=C000058881&_version=1&_urlVersion=0&_userid=3002350&md5=05d6824be035ffb16dbda698aff06b72

For those of you who can't manage to get it from there, PM me your e-mail address and I'll send it to you as a Word document.

Well, seeing as how I'm already here...

I've been thinking of stuff to do with this, and I was going over Tim Lewis's (IIRC) "Kitchen Improvised BC's" and it said how MHN tends to detonate if heated too fast (yes MHN, not a spelling mistake). Combine that with NHN's extremely rapid deflagration rate, and I'm thinking an intimate mixture of the 2 might be flame sensitive, if given a big enough charge to allow the deflagration-detonation transition; Normally very large for NHN (haven't actually managed to get there yet, I'm also thinking of packing a 6mm straw with the stuff) an MHN/NHN mixture might feature the NHN burning fast and hot, and plain old forcing the MHN to detonate from the rapid local overheating of crystals.

Any thoughts?
Pretty please?