| Pages:
1
2 |
quicksilver
International Hazard
Posts: 1820
Registered: 7-9-2005
Location: Inches from the keyboard....
Member Is Offline
Mood: ~-=SWINGS=-~
|
|
Copper Picrate?
I have a series of questions that I am hoping some can answer or point me in the right direction.
Certainly copper picrates are possible....
The questions I have are of metalic energetic compositons and their sensitivity. Realizing that certain heavier metalic molecules (lead, mercury) are
used in energetic materials, why is it that on occation when lighter metals are used (silver, copper) they exhibit greater sensivity in certain
compostions (azides, fulminates)?
In other instances copper & silver acyitide has been used with some success but often their sensitivity in other energetic materials are so high
that they are not employed for industrrial uses.
Could copper, nickel, and silver be utilized as picrates without undue sensitivity? Testing (Federoff, Urbanski) has noted that temprature for
ignition is within range of heavier metals. Experimentors have nitrated everything under the sun. At such a time of experimentation with energetic
materials, certainly work was done with metalic compostions....(?) Yet less toxic metals have been shown to have too great a sensitivity in some
materials and not others. Has there been greater experimentation with these materials than is commonly known?
What is it that makes some metalic elements impart greater sensitivity to certain energetic materials and yet to others they can play a productive
role?
My purpose for asking is my curiosity about less toxic metalic elements in energetic materials and their possable roles in everyday industrial uses
(airbags, etc, etc) - I know this is a lengthy query; & I appologize. I just thought that someone has some commentary or experience with this
subject greater than my own.
Thank you for any light you may shed on this subject.
|
|
|
Sickman
Hazard to Self
Posts: 98
Registered: 9-5-2004
Member Is Offline
Mood: Icy and I see!
|
|
QuickSilver,
First I'd like to say that I haven't the foggiest idea as to why the more heavy metal salts seem to be more sensitive or why for
example silver salts tend to degrade in sunlight. My best explanation is that it's just the way it is.
To answer your questions about copper picrate and the others about their sensitivity and industrial uses I can quote The Chemistry of Powder and
Explosives by Davis in a drop test of a 2-kilo weight (in inches) on various substances causing explosion in one or more instances in ten trials.
Mercury Fulminate 2"
Tetryl 8"
TNT 14"
Picric Acid 14"
Copper Picrate 12"
Zinc Picrate 12"
Ferrous Picrate 14"
Anyway, you get the idea that most of the picrates are very stable. Nickel picrate seems to be more sensitive with a drop of 4".
In the patent US5392713 a hydrated(making it less sensitive and probably less powerful) metal picrate is used as a substitute for lead azide. In the
British patent GB191123493 potassium picrate is used as a substitute for potassium chlorate in bullet primers. It also appears in the patents quite
regularly that ferrous picrate is used as a fuel additive for automobiles for better gas mileage.
In my own experiance with metal picrates I have found basic lead picrate to be the most useful. It can be used in place of lead styphnate to initiate
Lead azide in a firing train; it can also be used in bullet primers.
As far as getting good Vod rates and reliability for the initiation of high explosives, picrates just don't cut it at all.
Which is the main reason they are not used too much for such purposes commercially, militarily, or otherwise. In other words even the best picrates
such as basic lead picrate can't detonate TNT, Picric Acid, RDX or other significant HE's in a reasonable amount and with any degree of
reliability at all whatsoever. Which makes them quite useless in that regard, unless you are using the picrates as simple ignition compounds to
initate some primary explosive as lead azide mercury fulminate even DDNP which tends to suck in my own trials with it.
P.S. All the attempts in the literature to move away from lead azide to create a "safer" detonating cap just leads to a less reliable, less
economical "placebo" style detonator which only serves to make the inviromentalists happier and in light of all the rest of the crap
polluting the world, an INSIGNIFICANT compromise! Dido with the airbag! I like my sodium Azide just were it is!
|
|
|
quicksilver
International Hazard
Posts: 1820
Registered: 7-9-2005
Location: Inches from the keyboard....
Member Is Offline
Mood: ~-=SWINGS=-~
|
|
| Quote: | Originally posted by Sickman
-=snipped for brevity=-
In my own experiance with metal picrates I have found basic lead picrate to be the most useful. It can be used in place of lead styphnate to initiate
Lead azide in a firing train; it can also be used in bullet primers.
As far as getting good Vod rates and reliability for the initiation of high explosives, picrates just don't cut it at all.
Which is the main reason they are not used too much for such purposes commercially, militarily, or otherwise. In other words even the best picrates
such as basic lead picrate can't detonate TNT, Picric Acid, RDX or other significant HE's in a reasonable amount and with any degree of
reliability at all whatsoever. Which makes them quite useless in that regard, unless you are using the picrates as simple ignition compounds to
initate some primary explosive as lead azide mercury fulminate even DDNP which tends to suck in my own trials with it.
P.S. All the attempts in the literature to move away from lead azide to create a "safer" detonating cap just leads to a less reliable, less
economical "placebo" style detonator which only serves to make the inviromentalists happier and in light of all the rest of the crap
polluting the world, an INSIGNIFICANT compromise! Dido with the airbag! I like my sodium Azide just were it is! |
Thank you for the info and the patents. I continue to wonder about this and I suppose it's not as simple a question as it looks on the
surface.....
I only wish I could work with the British patents more effectivly; espacenet is a real pain; and there is such a good deal of information there.
|
|
|
Sickman
Hazard to Self
Posts: 98
Registered: 9-5-2004
Member Is Offline
Mood: Icy and I see!
|
|
quicksilver,
"espacenet is a real pain"
You've got that right. What I don't understand is why they don't have a more relative search engine. For example when I type in a
chemical name and search I would like it to bring up patents that tell me exactly how to manufacture it or a better way to recrystallize it. Instead I
get thousands of results that just mention it in passing and I have to search for hours to find anything.
Also when it comes to non-english patents such as japanese and german or russian I wish they would have an option to translate into english for
english users. Another thing that is really annoying with the search option is that it doesn't seem to bring up early patents like 1920's
1930's when alot of significant and original explosives were being developed.
|
|
|
quicksilver
International Hazard
Posts: 1820
Registered: 7-9-2005
Location: Inches from the keyboard....
Member Is Offline
Mood: ~-=SWINGS=-~
|
|
| Quote: | Originally posted by Sickman
quicksilver,
"espacenet is a real pain"
. Another thing that is really annoying with the search option is that it doesn't seem to bring up early patents like 1920's 1930's
when alot of significant and original explosives were being developed. |
That is -=EXACTLY=- where I was going with the under-current of my question on metalic energetic materials......During the time frame of the mid 19th
century onward, there has been SO MUCH EXPERIMENTAION that the answers to questions such as this most likly exist. But getting to the meat of the
thing usually involves access to a great library or national patents. Espacenet is a treasure of information: I have seen some of the stuff folks on
forums here gotten from there. Really useful stuff! But they will be the first people to tell you that it's a real hassle; indeed actual work, to
get the material that SHOULD be available to the public.
I honestly wouldn't put it past them (ESPACENET) to have a censoring element within their site.
And so I won't go too far off topic here, I would say at this point that I am working with cupric picrates now and believe that I have a usable
sample. I work with extremely small samples when doing experiments of this nature (sub-gram). What I have is a green material that needs to finish
it's time in the desicator (I dry slowly) so that I would maintain crystal shape for the microscope. It appears promising: I simply subsituted
anhydrous copper nitrate for lead nitrate in a standard proceedure.
|
|
|
Rosco Bodine
Banned
Posts: 6370
Registered: 29-9-2004
Member Is Offline
Mood: analytical
|
|
The formation of undesirable hydrates and low density crystal forms is what hinders the potential usefulness of copper and other metallic picrates .
Even the anhydrous salts of the metals which are known to form useful initiators can form as crystals which do not have useful explosive properties ,
except when the salts are made under a specific condition for their formation which produces the crystal form which does have the desired properties .
It requires very special conditions of temperature and concentration of reactants , pH and rate of reaction , and the vigorousness of the agitation
during mixing has bearing on the sort of crystals which will result . So it is known that there are many reaction conditions which greatly influence
the product , aside from the chemical equations which apply . The product is governed by many variables which have bearing , so what is the result
may differ very much simply from changing one of the variables about the reaction condition . A simple chemical reaction like A + B = ( A + B ) + or
- n ( HOH ) can produce a dozen different materials varying with the conditions for the reaction , with only one , or NONE of the dozen having any
useful explosive properties . The physical chemistry , crystalline form of the product has enormous bearing on explosive properties , and this is a
general rule for energetic materials which is even more applicable to primary explosives where the density and crystal form are especially critical ,
definitive actually , for what will be the explosive properties for the sample .
The mathematics applicable to energetic materials is very highly algebraic more than arithmetical , so you may find surprises which seem not to make
sense ,
compounds which by arithmetical logic would seem to be or should be expected to be more explosive or less explosive , and yet to confound your
expectation , the compound will manifest its own identity as it pleases , being what it will be according to its true nature , without any deference
to prediction or expectation of what it " ought to be " .
Barium Styphnate is one of the few materials which I have seen mentioned as having usefulness , other than the lead salts which are well known . The
usefulness of most of the energetic metal salts occurs when the salt is a component of a complementary mixture with other similar salts . This is
because generally no single compound itself has all the desirable properties present to perform the task required , so composite mixtures are used to
embody the desirable properties of each components contribution to a " hybrid " mixed composition . Multiple salts and clathrates have the
advantage for this reason , and are most interesting for experimentation . It is unlikely that any
single " simple salt " intitiator will be found which demonstrates the combination of desirable properties of a complex salt " hybrid
" . That search has already been made by many different researchers who pretty much never discovered any single compound simple salt , "
perfect initiator " ......but did find a few complex salts and complementary mixtures which are very close to perfection . The complex salts
are then really where the focus of experiments should be if the interest is in advanced technology for initiators . And with regards to "
getting the lead out " , well possibly that can be done , and the silver , copper , nickel , possibly cobalt , and barium combinations are likely
candidates in that quest , but as mixtures or complexes ....and beyond picrates , involving styphnates and tetrazoles ,
and possibley some of the hydrazine derived complexes of nitroguanidine or DDNP . It would be my guess that is the
direction your experiments will go when things dead end on any single simple salt picrates , because that ground has already been covered , more than
likely ,
and if anything satisfactory had been found , then it would already be in common use .
|
|
|
quicksilver
International Hazard
Posts: 1820
Registered: 7-9-2005
Location: Inches from the keyboard....
Member Is Offline
Mood: ~-=SWINGS=-~
|
|
| Quote: | Originally posted by Rosco Bodine
Even the anhydrous salts of the metals which are known to form useful initiators can form as crystals which do not have useful explosive properties ,
except when the salts are made under a specific condition for their formation which produces the crystal form which does have the desired properties .
It requires very special conditions of temperature and concentration of reactants , pH and rate of reaction , and the vigorousness of the agitation
during mixing has bearing on the sort of crystals which will result . So it is known that there are many reaction conditions which greatly influence
the product , aside from the chemical equations which apply . The product is governed by many variables which have bearing , so what is the result
may differ very much simply from changing one of the variables about the reaction condition . A simple chemical reaction like A + B = ( A + B ) + or
- n ( HOH ) can produce a dozen different materials varying with the conditions for the reaction , with only one , or NONE of the dozen having any
useful explosive properties . |
Could this be why copper does not respond to the "fulminate process" as does Hg?
Both copper nitrate and nickel nitrate are so damn hygroscopic that they must be prepped (dryed out extreamly well) to even begin to work with their
proper weights. The water they hold is unbelievable.
I have been working with both and believe that I have a nickel picrate now. It is emerald prismatic in color and shape. Response to flame is
lack-luster as wet lead styphnate but it does respond.
My sideline is hobby rocketry and I found a wonderful concept in the development of bridgless ignitors....at issue is not only the resistance and
eletrical conductivity but also the "pop"...it must be continuous and possess a strong flame. - You got me hooked on patents for my
information and I have found some of the BEST US patents on bridgeless ignitors (US3320104, US4968364) but therein the inventor used lead styphnate.
The conductivity of picrates is better suited to the needs of a bridgeless ignitor; the need for a carrier and a resisance component (graphite) may
not be needed. But lead picrate "pops" when used in such a fashon, while nickel picrate may not...it appears thus far I have found the
component, that being nickel picrate. Using Nickel nitrate (anhydrous) and applying the the basic (sodium hydroxide) picrate synth previously
discussed, I think this will work. And true enough, I have had little luck using copper nitrate. [A simple test with a multi-meter reviels the
conductivity of picrates, regardless of crystal shape, etc.]
The fulminates (being almost kitchen chemistry) have proven fruitless in any attempt at the introduction of copper during the standard Hg synth. Even
though I ahd found the correct time for introduction of copper during the production of mercury fulminate (the only way I know to make copper
fulminate), the product not only lacks conductivity but is totally inconsistent from one batch to another. No matter how carefully I monitor temp and
time. Oh, I have gotten product but from one batch to another; the consistency is terrible....
Once again what you say has rung true....ruefully I have given up on fulminates as being much too filled with unknowns to extrapolate the use of other
metalic materials for a usefull energetic material. Picrates are at least predictable.
- Sorry about jumping from picrates to fulminates here but what is being discussed appears to ring true for both.
|
|
|
Rosco Bodine
Banned
Posts: 6370
Registered: 29-9-2004
Member Is Offline
Mood: analytical
|
|
Silver powder or precipitaed silver has been used to make conductive compositions . For one variant IIRC , silver azide can be treated in such away
as to reduce the surface of the crystals in suspension to metallic silver , which makes them conductive .
Bright aluminum dust of the extremely fine mesh airfloat variety , and possibly zinc dust or other fine metal powders could also give conductive
mixtures .
Potassium picrate of a very specific crystal variety which is made by a patent process has also found usefulness in primer igniter compositions while
other more usual forms of potassium picrate are not useful .
It would seem to me that a clathrate of
precisely intended burn rate could be easily made which would work well as a single compound igniter , enhanced as to conductivity and flame
temperature by mixture with a metal powder .
There have been developed a good many different bridgewire " bead " compositions
which are deposited as a paste or slurry and then harden to a pellet adhering to the bridgewire . Some of these are probably adaptable to use as
conductive compositions . Actually , in high reliability firing trains , there can be redundancy achieved by using a conductive composition even
though a bridgewire is present , and then firing with a high enough voltage that it is guaranteed the
device will function , whether the bridgewire functions or not . High enough voltage and current even eliminates the essential need for the primary
, as the base charge can be fired by the thermal shock and impulse from the sudden pop of the arc as a last redundancy in a device having about four
independant paths which simultaneously provide different possible paths to detonation . You might find something like this scheme applied in a
missile warhead where it is desired to be absolutely damn sure a dud is avoided with an expensive munition , so they use layered redundancy to
guarantee functioning , multi-detonators each having multi-path to detonation capability .
|
|
|
Axt
National Hazard
Posts: 778
Registered: 28-1-2003
Member Is Offline
Mood: No Mood
|
|
I realise your after a single compound for the igniters, but also have a look at US2970047 & US3090310, I've been meaning to try replacing
graphite bridgewireless igniters with PbO2. Which can both provide the required resistance and act as an oxidiser. Perhaps in combination with Ti for
its low conductivity & hot splattering thermite reaction.
|
|
|
quicksilver
International Hazard
Posts: 1820
Registered: 7-9-2005
Location: Inches from the keyboard....
Member Is Offline
Mood: ~-=SWINGS=-~
|
|
| Quote: | Originally posted by Rosco Bodine
Potassium picrate of a very specific crystal variety which is made by a patent process has also found usefulness in primer igniter compositions while
other more usual forms of potassium picrate are not useful .
It would seem to me that a clathrate of
precisely intended burn rate could be easily made which would work well as a single compound igniter , enhanced as to conductivity and flame
temperature by mixture with a metal powder .
There have been developed a good many different bridgewire " bead " compositions
which are deposited as a paste or slurry and then harden to a pellet adhering to the bridgewire . Some of these are probably adaptable to use as
conductive compositions . Actually , in high reliability firing trains , there can be redundancy achieved by using a conductive composition even
though a bridgewire is present , and then firing with a high enough voltage that it is guaranteed the
device will function , whether the bridgewire functions or not . High enough voltage and current even eliminates the essential need for the primary
, as the base charge can be fired by the thermal shock and impulse from the sudden pop of the arc as a last redundancy in a device having about four
independant paths which simultaneously provide different possible paths to detonation . You might find something like this scheme applied in a
missile warhead where it is desired to be absolutely damn sure a dud is avoided with an expensive munition , so they use layered redundancy to
guarantee functioning , multi-detonators each having multi-path to detonation capability . |
Aluminum has the capasity to lubricate as well. Fitting a friction sensitive compound in a tube or other assembly is made easier and safer by the
application of flake Al to the area or component. It is a wonderful asset in construction of ignitors (as is graphite) but the added benefit of Al is
that it continues the flame. In the rocketry hobby the final rocket and altimeter can cost several hunderd dollars if not more so. So I really want to
make sure that both initial stage and booster-'cute deployment fires. The main issue is that one must depend on battery power for all seconday
issues. Therefore an ignitor MUST funtion (to deploy a recovery 'cute or a seconday stage) with low voltage and moderate current; yet it must not
be static sensitive. The added bridge-wire is a great insurance policy. The problem, of course is soldering a human hair size wire.
The clathrate idea is something I have not had not yet really experimented with. I don't know if it is as conductive as picrates / styphnate
compounds. There exists the caged lattice (of which you know better than I) and superficially I believe that may offer some electrical resistence.
Which is often a good thing; creating a source of heat when current is applied.
With picrates / styphnate compounds the use of graphite and a "carrier" is employed to this end and the correct ratios must be found.
It's a time consuming agenda. Generally one is looking for 1-5 ohms w/ a battery assembly. With a cap-discharge unit one may go as high as 12
ohms.
The standing formula for a bridgless ignitor is:
KCLO3 55%
graphite/ conductive lampblack 25%
Al 5%
lead dioxide 9%
Mg 5%
Manganese dioxide 1%
Carrier agent or binder is NC Laquer
This will work very well but it's quite complex to adjust to a specif electrical charge.
While the patent US 4968364 uses a very simple approach:
lead styphnate (or one may use picrates) 95% + /- 1-2%
graphite 5% + /- .35%
Cellulose acetate & acetone as binder.
Adjusted by milligrams to fit most anything;
you can see that it's a dream come true but the use of lead picrate creates a pop, while another metal may result in a surge of flame; perfect
for an ignitor.
Now the clathrate concept is an important consideration because if a clathrate is not completly dry it flames (then pops). If a carrier agent such as
cellulose acetate / acetone were used to hold the mixture togehter it may be much more cost effective.
The most important issue is how it conducts.....if there is resistence, that can be worked out via a streight conductor metal or graphite. If it is a
strong conductor then resistence must be applied via a binder.
Have you seen any (non-US) patents in this regard on ESPACENET? If so, let me know so I can try once more to get their stuff....I am hooked on patents
and I want to make that site useful for me finally.
Thanks again.
|
|
|
Sickman
Hazard to Self
Posts: 98
Registered: 9-5-2004
Member Is Offline
Mood: Icy and I see!
|
|
Dear Rosco Bodine,
It seems that I remember you mentioning something about adding a chlorate to an azo-clathrate solution to change the characteristics of the final
complex.
Anyway I wasn't sure if it was concluded in US3431156 that only a lead salt could be used to entrap additional amounts of lead azide. What
I'm wondering here is would it be possible to come up with a way of trapping lead azide in copper picrate or some other picrate besides the basic
lead picrate of the patent. It seems like first the lead azide would be made in a solution and then picric acid, sodium hydroxide and a copper salt
would be added to that to make copper picrate, which would hopefully trap large amounts of lead azide in it's crystal lattice as the copper
picrate crystallizes in the lead azide solution. Would any of this be possible or worth the experiments? If you think a basic copper picrate- lead
azide clathrate is not possible please explain your reasons for thinking this.
As always thank you for your replies.
[Edited on 5-10-2005 by Sickman]
[Edited on 5-10-2005 by Sickman]
|
|
|
Rosco Bodine
Banned
Posts: 6370
Registered: 29-9-2004
Member Is Offline
Mood: analytical
|
|
Copper can form so many different azides that have the potential for sensitivity dangers , that it would probably not be one of my first choices for
experimentation with azide containing clathrates . Bismuth is a metal rarely mentioned and might be worth considering as a possible analogue for
lead , however what may be its usefulness for clathrate formation I don't know . Igniter compositions are not where you would want to form an
azide containing clathrate because the azide makes those compositions detonating instead of igniting compositions . The slower burning clathrates
like the dibasic or tribasic compounds would be likely candidates for an igniter squib for a rocket engine , where a long duration burning match
composition is what is desired . The inclusion of chlorate or perchlorate in a clathrate tends to make it
burn faster and hotter than similar clathrates which only contain nitrate as the oxidizer , so in that regard it is similar as with mixtures . The
basic lead picrate / lead nitrate based clathrates obey the rules for proportional composition described by the patent for the lead compounds . It
may be that if different metal basic lead picrates do form that they will follow the same pattern , or they may follow a different rule for their
formation . I haven't experimented with all of the possible lead compounds and none at all with efforts at clathrates based on other metal basic
picrates than lead . Just because the basic lead picrate can form clathrates in no way assures that the same is possible for other basic metal
picrates . There may be a few other basic metal picrates which behave the same way ....or none of the others except for lead . There are also many
possible double or multiple salts which are not clathrates , but have similar value .
One of the possibilities which has crossed my mind about the clathrates is to attempt introduction of mercury fulminate into the basic lead picrate /
lead nitrate matrix . It is a little known fact that Mercury Fulminate is significantly soluble without decompositon in boiling water , from which it
may be recrystallized as salt like white crystals which deposit on cooling . So it seems possible that a similar fulminate-clathrate series of
compounds could form in analogous fashion as do the azo-clathrates . This could be an interesting line of experimentation for possibly useful
fulminate complexes never before described and possibly unknown altogether . The storage stability and performance and physical properties of such a
theoretical fulminate-clathrate could possibly be superior to fulminate alone . If such a clathrate is possible and has good properties , it sure
would bring new value and usefulness to the good old original initiator , mercury fulminate . So does this sound like a worthwhile experiment ? 
[Edited on 5-10-2005 by Rosco Bodine]
|
|
|
quicksilver
International Hazard
Posts: 1820
Registered: 7-9-2005
Location: Inches from the keyboard....
Member Is Offline
Mood: ~-=SWINGS=-~
|
|
| Quote: | Originally posted by Axt
I realise your after a single compound for the igniters, but also have a look at US2970047 & US3090310, I've been meaning to try replacing
graphite bridgewireless igniters with PbO2. Which can both provide the required resistance and act as an oxidiser. Perhaps in combination with Ti for
its low conductivity & hot splattering thermite reaction. |
Good stuff...thanks. I think that US 4968364 does present some info on PbO2 but I don't remember if it was from a conductive, adjuntive
perspective or what.....I think I may have some Ti fines around here for that purpose, I imagine I would need -325 mesh or finer. The good thing about
oxides is that they will generally be conductive and mix well. While metal powders can be hard to find as fine grain (except Al of course). I just
happen to have a ridiclous amount of Cu powder, the coursest is -425 (some at sub-sieve level!) & the usual Al (Ekhart 5413, etc).
The nickel picrate is all dried now and really did come out pretty good considering that both nickel nitrate and copper nitrate are as hygroscopic as
I have yet seen! About a third their weight is water and that will throw off any chem synth to the point of failure.
|
|
|
quicksilver
International Hazard
Posts: 1820
Registered: 7-9-2005
Location: Inches from the keyboard....
Member Is Offline
Mood: ~-=SWINGS=-~
|
|
| Quote: | Originally posted by Rosco Bodine
One of the possibilities which has crossed my mind about the clathrates is to attempt introduction of mercury fulminate into the basic lead picrate /
lead nitrate matrix . It is a little known fact that Mercury Fulminate is significantly soluble without decompositon in boiling water , from which it
may be recrystallized as salt like white crystals which deposit on cooling . So it seems possible that a similar fulminate-clathrate series of
compounds could form in analogous fashion as do the azo-clathrates . This could be an interesting line of experimentation for possibly useful
fulminate complexes never before described and possibly unknown altogether . The storage stability and performance and physical properties of such a
theoretical fulminate-clathrate could possibly be superior to fulminate alone . If such a clathrate is possible and has good properties , it sure
would bring new value and usefulness to the good old original initiator , mercury fulminate . So does this sound like a worthwhile experiment ?
[Edited on 5-10-2005 by Rosco Bodine] |
My dear Roscoe, if you could find a method of making fulminates consistent from batch to batch I would eat my hat! I had once thought that Picric Acid
was a finicky little devil but in my opinion it doesn't hold a candle to the damnable fulminates!
Curse them for the kitchen-chemisrty that they be! Damn the fulminates....and damn their 19th century "formulas".
I have made my share of Hg fulminate and have yet to KNOW that the batch will turn out with full, well shaped crystaline structure OR heavy amounts of
mercury nitrate fine powder clogging up the batch. I keep a accurate lab, and watch my measurments; but I give you my word on this....I can't
predict from one batch to another if my Hg fulminate will duplicate itself well enough to be used in a proper synth involving other compounds. If you
figure a method to control reaction temp/time from the moment the alcohol goes in, my hats off to you. I say this in humor of course, but really....I
have a real bitch of a time with it; no kidding.
What I have determined is that, at the point that the alcohol is placed into the mercuric nitrate/HNO3...there is an uncontrolable time lag before the
reaction....and it's this time lag upon which the fulminate result hinges. Even if kept at one consistent temp there exist variables that seem to
me to be uncontrolable.....I get very frustrated with making fulminate. Sometimes I have made fulminate that has the best look and response I could
have ever wanted and at others, using the same ratios and temps, I get crap......damn mercury fulminate!
|
|
|
Rosco Bodine
Banned
Posts: 6370
Registered: 29-9-2004
Member Is Offline
Mood: analytical
|
|
The trick is that you have to add the alcohol to the mercuric nitrate and HNO3
solution while it is still very warm from the dissolution of the mercury , and still contaminated with nitric oxides . Both the elevated temperature
and the presence of the nitric oxides are necessary for the reaction to start quickly with the alcohol .
If you are using pre-made mercuric nitrate
and experiencing trouble , it is because of the lack of nitric oxides . Add a little sodium nitrite or perhaps a bit of starch or paraformaldehyde
and warm to initiate some decomposition of the nitric acid before adding alcohol to the warm mixture , and then the reaction should start quickly and
run hot as it is supposed to do . Use a flask large enough to accommodate the violently boiling reaction and provide enough surface area to allow
refluxing on the inside walls which
are air cooled . I am no expert on mercury fulminate so I can't give you an optimized synthesis , but I can look through my notes and see what
references I have which may be useful .
I have made it a few times , but haven't gotten great yields , probably for not using pure ethanol , but used instead the denatured variety ,
which is not recommended , and tends to reduce the yields .
There's a pretty good discussion on fulminates in the following old thread at E&W
http://www.roguesci.org/theforum/showthread.php?t=297&pa...
[Edited on 6-10-2005 by Rosco Bodine]
|
|
|
quicksilver
International Hazard
Posts: 1820
Registered: 7-9-2005
Location: Inches from the keyboard....
Member Is Offline
Mood: ~-=SWINGS=-~
|
|
| Quote: | Originally posted by Rosco Bodine
The trick is that you have to add the alcohol to the mercuric nitrate and HNO3
solution while it is still very warm from the dissolution of the mercury , and still contaminated with nitric oxides . Both the elevated temperature
and the presence of the nitric oxides are necessary for the reaction to start quickly with the alcohol .
There's a pretty good discussion on fulminates in the following old thread at E&W
http://www.roguesci.org/theforum/showthread.php?t=297&pa...
|
You may just have hit it on the bean with that one - I'll give it a try this weekend. I actually use the name quicksilver as a reminder to myself
to stay humble with my feeble attempts @ my hobby. For as much as I have done a fair job at somethings, an old-time quirky thing like fulminates gives
me a challenge I have yet to say I can reliably reproduce the results thereof (always my goal).
I _DID_ work with the hcl purification you had mentined and damn it, if it wasn't the more productive thing I had worked w/ in quite some time. I
had kept some "orange-ish" picric acid I had made many moons ago and I got myself a half pound of really good looking PA!
Now the patent you posted was VERY interesting....I too have studied the COPAE ('till she was dog eared) and I seem to remember something about
the catalytic form of PA production (I -=think=- it was in the COPAE....) and wondered if anyone actually tryed it. Now here I see an actual patent
mentioning the mercuric nitrate format for PA production!
The facinating thing is that when looking at the formulation written down (I am not the best at that as my chem was undergrad level) It does not seem
to make sence (no benzene, etc). But yet it must work and I would bet it has a scalability that is more flexable then that of direct nitration of
clean phenol.
I only wish that this type of dicussion was available when I was in school. How valuable it must be to those who are and are reading these threads
right now.
That is one reason I copy many of the discussions here and in E&W, you just can't get this info or the amount of input from so many varied
sources and so many folks who share the same hobby. Not to mention the appliciablity of the material to such a vast venue.....pretty cool stuff.
|
|
|
quicksilver
International Hazard
Posts: 1820
Registered: 7-9-2005
Location: Inches from the keyboard....
Member Is Offline
Mood: ~-=SWINGS=-~
|
|
MERCURY PICRATE...
Roscoe, I read with interest your posts on E&W....you did just what I had done. You used denatured industrial alcohol...that MAY be the issue here
(due to impurities, etc). I think that since our results were the same (tan fine crystal, poor yield, etc) that the ethanol source is a major problem.
I will be addressing that soon. The other thing you spoke of was the use of the poorly made fulminate turned into a mercury picrate (or, I thought;
styphnate). But as we see the nesessity for the (mercury fulminate) solution to be 7.5 grams to one liter of 100C H2O is problematic for the synth of
a picrate without wasting PA.....Or at least I get that from what I have read thus far.
How would one go about generating a mercury picrate (using imperfect Hg fulminate) if our solution was that high in H2O? Could styphnic acid be a more
efficient choice? I think there is something here.....could a crystaline lattice be generated? Has this even been attempted previously and what might
be the pitfalls or dangers (aside from toxicty, etc)? Would a teflon stir-bar generate too much friction in this synth? It _has_ in silver fulminate:
a good friend ruined some glassware dextrinating same some time ago. What do you think could be done here?
|
|
|
Rosco Bodine
Banned
Posts: 6370
Registered: 29-9-2004
Member Is Offline
Mood: analytical
|
|
Mercury picrate is news to me .....
You must have misread something or
misunderstood .
BTW ......
I have an experiment underway now where I am attempting to recover any residual picric acid remaining in the distilled water which I have saved from
final recrystallizations . I found that if I stirred in small portions of washing soda and observed for effervescence I could manage a rough
titration , neutralizing the
residual acidity to form the soluble sodium salt . I observed that not only does the effervescence subside from appearing as
vigorously with each new portion of sodium carbonate added to indicate the approaching neutralization point , but there is also a sudden color shift
to a darker color right at the equivalence point , so the sodium picrate solution is in effect its own color indicator for titration ....how
convenient .
To the solution of sodium picrate is added by portions and with stirring to dissolve , potassium nitrate , which reacts with the
sodium picrate by double decomposition and precipitates the only slightly soluble potassium picrate , leaving a residual solution of mostly sodium
nitrate .
This appears to be a valid method for recovery of picric acid as its potassium salt from relatively dilute solutions which might otherwise be simply
discarded .
The solubility variation for the potassium picrate is much greater than the variation for picric acid itself , in terms of the reduced solubility at
room temperature compared to the solubility at the boiling point , and this along with the salting out effect of the sodium nitrate byproduct , makes
the precipitation of the potassium picrate proceed to a significant degree of completion . So don't throw away those
leftover solutions from recrystallization , if you have a liter or more .....you should try this simple recovery method . The precipitated potassium
picrate is very fine mesh , but can be dissolved on heating and then cooled slowly to get larger crystals . The potassium picrate can be used for
different purposes , or converted to picric acid with HCl .
|
|
|
pdb
Hazard to Self
Posts: 70
Registered: 8-4-2004
Member Is Offline
Mood: No Mood
|
|
Useless MF discussion
Quicksilver, I think this discussion about MF is meaningless. If you had more knowledge of chemistry in general and fulminates synthesis in
particular, you would be aware that some reactions, such as this one, are intrinsically extremely complex, involving not less than 8 subsequent and/or
simultaneous sub-reactions from only 3 initial components, to lead eventually to the MF precipitation. This is a first explanation for the variability
you observed in MF preparation. Second, with such a complex chemical train, involving very exothermic reactions, one can easily understand that its
performance will depend a lot on the preparation circumstances that may affect heat exchanges, and thus temperature. Depending on your apparatus, the
quantities of chemicals, the shape of the vessel (which affects the ratio surface/volume on the one hand, and the condensation of volatile by-products
on the other hand, both effects having an impact on heat exchange), HNO3 concentration, alcohol purity, ambient temperature, etc etc, sometimes you
will have to heat the vessel to start the reaction, some other times you will need to add fresh alcohol to reduce its pace, MF precipitation will
require a few minutes, a few dozens of minutes… or never happen (which is actually quite exceptional). Third, the literature is full with studies
and report dealing with the "brown", "grey", "white", "white-grey", "brownish", and so on… MF, all
these compounds being 95% and more of pure MF, but contaminated either with Mercury, or some polymerised by-products or other chemicals like the ones
used to denature commercial alcohol, or all them together. For a hobbyist usage, that makes almost no difference and you can use any of them. For the
sake of purity, you can dissolve your crop in concentrated NH4OH and then recrystallise MF as a white powder… Last, if you are dissatisfied with MF
because of the variety of factors that intervene in its synthesis, don't even think about silver fulminate, whose reaction is even more chaotic
and difficult to control ! (after many crops, I still sometimes end up with no precipitate at all). Not to mention that the extreme sensitivity of SM
would not go well with your lack of familiarisation with such stuff.
|
|
|
quicksilver
International Hazard
Posts: 1820
Registered: 7-9-2005
Location: Inches from the keyboard....
Member Is Offline
Mood: ~-=SWINGS=-~
|
|
| Quote: | Originally posted by pdb
Last, if you are dissatisfied with MF because of the variety of factors that intervene in its synthesis, don't even think about silver
fulminate, whose reaction is even more chaotic and difficult to control ! (after many crops, I still sometimes end up with no precipitate at all). Not
to mention that the extreme sensitivity of SM would not go well with your lack of familiarisation with such stuff. |
It is EXACTLY that element of inconsistency that makes any discussion of the process meaningful.
Think about what you just said....after understanding (and I asume you do) all the variables you still have trouble with reproduction of a consistent
end-result.
Come on....relax.....this is no big deal....we are simply talking about hypothetical stuff: what's to be so uptight about?
I apprieciate that you may be concerned that I know less than yourself; and I may. But I do know the basic concepts of fulminating compounds. I am
simply not afraid to say that something doesn't make sence to me or I don't understand fully certain issues. I just don't have to know
everything; that's why I ask questions. And why I listen and read... You make a point that a discussion is meaningless because a reaction is
complex. And that complexities are somehow either mastered or not discussed...????? Sir, that does not make sence in the light of a discussion board
on chemistry.
You make a further point that MF can maintain itself in various forms and that from a hobbyiest perspective it makes no difference. But yet it does.
As you certainly know some forms are non-reactive, some yields are so low as to be inappropriate to the time invested, and some may be perfect for the
application. What in Heaven's name is wrong with discussing the idiocyncracies of that individuation?
Why are you angry? It seems odd to be angry or even bothered by someone's questions.....If you don't like something on TV do keep watching?
I just turn it off. If I am so damn offensive just stop reading anything I write & assume I am a knave and dull and I have nothing that would
interest you. On the other hand, if you really have an outstanding education and communication skills and you find it entertaining to help folks with
less knowlege than yourself you might want to clearify areas wherein I might learn more...and I would certainly be greatful.
But you need not discribe in detail Edward Howard's work as I am quite familiar. Nor Brugnatelli's for I know that well also.
However, I do apprieciate your concern for my well being and if that was the thrust of your diatribe, I certainly applogise for misinterpreting your
remarks.
|
|
|
quicksilver
International Hazard
Posts: 1820
Registered: 7-9-2005
Location: Inches from the keyboard....
Member Is Offline
Mood: ~-=SWINGS=-~
|
|
| Quote: | Originally posted by Rosco Bodine
Mercury picrate is news to me .....
You must have misread something or
misunderstood .
|
I certainly could have misunderstood, or even snipped it out of context but I kept the textfile of the whole discussion....
I don't remember if it was you or the other fellow you were speaking with, within that series of posts in E&W but toward the end of the
dialog...and I quote directly from there:
"The solubility of the mercury fulminate in hot water is something I keep thinking about
in terms of how this could be useful . One idea that has occurred to me is that perhaps
mercury fulminate may form a double salt with mercury or basic mercury picrate and
if it does , then this material could have useful properties."
Does that ring a bell? Was it you who spoke of the solubility factors; as they seem to be a insurmountable issue.
But be that as it may: it was a great dialog and I kept the whole of it as therein you discussed exactly the issues I had encountered. I am glad you
remembered that diaglog to begin with.
|
|
|
pdb
Hazard to Self
Posts: 70
Registered: 8-4-2004
Member Is Offline
Mood: No Mood
|
|
Quicksilver, I didn't mean to be arrogant or whatsoever. I just meant that trying to secure on a small or micro-scale a process to obtain certain
reproductibility in MF preparation is not far from impossible, and almost pointless, as in most instances you will effectively succeed your synthesis.
To me, it's much more important to secure a regular process for preparing NG for instance, since this nitration can be repeated very precisely,
with same conditions and same yield than try to "streamline" MF manufacture, given the intrinsic chaotic aspect of this particular reaction.
In other terms, if your goal is to prepare MF, this discussion is not required, and if it is to make MF synthesis (on lab scale) 100% predictable, it
is very likely out of reach. In my opinion, a clue that this reaction cannot be streamlined lies in the great number of recipes you can find in the
literature. Not talking of amateur' recipes, but industrial processes, that varied from a country to another one, and along time also.
|
|
|
Rosco Bodine
Banned
Posts: 6370
Registered: 29-9-2004
Member Is Offline
Mood: analytical
|
|
@quicksilver
Right , mercury picrate and basic mercury picrate ..... I remember now as an earlier thought about possible complex or multiple salts with mercury
fulminate ,
analogous to the basic lead picrate , lead
nitrate complexes with lead azide .
What I was getting at there in that old thread , is that possibly a mixture of mercuric nitrate with sodium picrate could form a basic mercuric
picrate which could be held in suspension in boiling hot water as mercury fulminate was sprinkled into the suspension , and that possibly a multiple
salt would form , like basic mercury picrate / mercury nitrate / mercury fulminate triple salt . Such a reaction would be analogous to what is done
with lead salts and lead azide .
Another possibility is to form the basic lead picrate / lead nitrate double salt which is the matrix former for the lead multiple salt clathrates ,
but to see if mercury fulminate itself could be adsorbed into the lead compounds matrix .
|
|
|
quicksilver
International Hazard
Posts: 1820
Registered: 7-9-2005
Location: Inches from the keyboard....
Member Is Offline
Mood: ~-=SWINGS=-~
|
|
| Quote: | Originally posted by Rosco Bodine
BTW ......
I have an experiment underway now where I am attempting to recover any residual picric acid remaining in the distilled water which I have saved from
final recrystallizations . I found that if I stirred in small portions of washing soda and observed for effervescence I could manage a rough
titration , neutralizing the
residual acidity to form the soluble sodium salt . I observed that not only does the effervescence subside from appearing as
vigorously with each new portion of sodium carbonate added to indicate the approaching neutralization point , but there is also a sudden color shift
to a darker color right at the equivalence point , so the sodium picrate solution is in effect its own color indicator for titration ....how
convenient
|
I don't remember if it was in this contextual agenda that you had once addressed this before but I seem to remember something you were once
talking about that was close....
I think it was in the context of mercury fulminate (I'm getting fuzzy now with both compounds). Using a solution of sodium carbonate (or bicarb)
and given the solubility factor to precipitate mercury carbonate. Continuing to add (in drops) the carbonate as further mercury fulminate dissolves,
continuing a reaction to the completion of sodium fulminate.
I'm digging this up from memory so forgive me....The thrust was to initially employ sodium chloride within a solution of MF so as to precipitate
sodium fulminate, which then could be used to precipitate many differing fulminates in a cold process by mixing w/ a solution of metalic nitrates.
acetates, etc. But there was the idea of using carbonate (I don't remember the reason as to why, however) rather than the sodium chloride.
I'll bet it was a solubility issue, but I don't remember....did you ever do that experiment?
-=OK...let's forget the damn fulminates for a second=-
However you are now activly doing an experiment; viewing a rough titration with PA somewhat similarly. And if this is successful the result would be
[elimination (or great reduction) of residual acidity to form a soluble sodium salt]: to utilize color indictors where they did not exist (or to any
great extent). This then would give you guidlines where none had previously existed. Yes?
Damn baking soda goes a long way!
In the offing one gets to stop wasting PA (the baby and the bathwater or wash-water as it were). Have you tried this as of this writing....??
In-so-far as the recovery method you mentioned: you bet I'm going to try it. If I were to really dig up all the bottles of nitrated phenols that
were less than what I wanted for personal usage (I keep 'em) I think I have a seriously LARGE amount to work with. I used the simple HCl
re-crystalization on one bottle and got about 250 grams of really good looking product where the PA was too "orange" for me.
I also want to try it with styphnic acid (can't think of a reason not to) as I have a bunch that was left over from experimenting with
nitrites....
Very cool idea.
|
|
|
quicksilver
International Hazard
Posts: 1820
Registered: 7-9-2005
Location: Inches from the keyboard....
Member Is Offline
Mood: ~-=SWINGS=-~
|
|
| Quote: | Originally posted by pdb
Quicksilver, I didn't mean to be arrogant or whatsoever. I just meant that trying to secure on a small or micro-scale a process to obtain certain
reproductibility in MF preparation is not far from impossible, and almost pointless, as in most instances you will effectively succeed your synthesis.
To me, it's much more important to secure a regular process for preparing NG for instance, since this nitration can be repeated very precisely,
with same conditions and same yield than try to "streamline" MF manufacture, given the intrinsic chaotic aspect of this particular reaction.
In other terms, if your goal is to prepare MF, this discussion is not required, and if it is to make MF synthesis (on lab scale) 100% predictable, it
is very likely out of reach. In my opinion, a clue that this reaction cannot be streamlined lies in the great number of recipes you can find in the
literature. Not talking of amateur' recipes, but industrial processes, that varied from a country to another one, and along time also.
|
Agreed. I doubt very much that industrial scale predicability could be achieved w/ MF by us working in our labs; make-shift or otherwise, for so many
reasons. I think I even remember reading that when those great "balloons" were in use, there were continual changes that had to be
implimented. I imagine that the simple change in temperature of a door being open or the ethanol being cooler, or God knows what, would throw off that
bastard.
My point however is that any discussion where "thinking out of the box" is implimented is a productive one as it gets the wheels turning of
those who may know something more or perceive something differently than oneself. This "thinking out of the box" is how the clathrate
concept was developed I believe. If memory serves, originally a Nun had worked w/ clathrates but I do not believe she was the one to apply it toward
energetic materials.....
So let's say you dream up an idea or ponder a problem that seems to turn you around in circles.....Often by discussing it with others they may
invision something from their personal experience that will have an effect, or not, or may effect the way you invision the problem itself. In any
event I really do believe that there is no such thing as a wasted experiment; only additional data.
I just love the idea of "thinking out of the box".
|
|
|
| Pages:
1
2 |
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
