Chemical Smokes

[A-BOMB]

I was wondering what kinds of chemical smokes are out there, theres the one in the makeshift arsenal which is clorine+antifreeze, then there was one in the magicians arsenal which was HCL+ ammonia, then KMNo4+glycerin in a small container (for me that just explodes no smoke). So what other chemical smokes are out there, I mean easy ones not things involving crazy hard to find chems like CF3 and the like.

[Sparky]

Certainly you've heard of the 4/6 sucrose/potassium nitrate smoke. My friend has made it many times and found that it is not actually a very effective smoke. Much of the smoke I think is water because it quickly dissipates, and the smoke does not stay on the ground well at all. A 5/5 is an improvement but stil not great.

My friend has tried this smoke with good success. His notes are included here:
White Smoke Type A, 127' (from Military and Civilian Pyrotechnics)
zinc dust 38.5
Hexachloroethene 46.5 (74.4 PVC)
ammonium chloride 3
potassium perchlorate 12

**You should be able to replace the hexachloroethene with 74.4 part PVC.
Notes: Made some with PVC. If it gives a yellow flame while burning then it gives little smoke. With this flame blown out, you get lots of brownish smoke that is kind of bad smelling. The composition must be packed into a tube and burn under pressure. Otherwise it slowly smoulders without much smoke. Burns slowly with lots of carbon 'sponge' leftover. Can be lit with blackmatch.

My friend came to the conclusion that PVC could be substituted for hexachloroethene because he saw a composition in wouter's database called Smoke composition #2 which says that PVC can be substituted for hexachloroethane (I think hexachloroethane is the same as hexechloroethene, right?). I strongly suspect it does not produce as much smoke as hexachloroethene though since otherwise the military would probably use PVC since it is cheaper (I think) and non poisonous.

There is a variation on the above formula that can be found in the same book. It burns even more slowly and is intended as the main charge in a smoke grenade. The above formula is to start the grenade off. Military and Civilian Pyrotechnics is on the forum FTP.

There is an old topic about a smoke device using parrafin. It uses 5/5/2 potassium nitrate/sucrose/paraffin shavings. The mix is put loosely in a steel can with holes in it, then the can is crimped down, an the mix is lit from the top. My friend tells me that parrafin shavings are very prone to static electricity, so be careful. He has never actually tried this mix before. Some other smoke formulas are mentioned in the same thread.

[Mr Cool]

With potassium nitrate/carbohydrate smokes, you want it to burn as vigorously as possible, preferably at or near OB.

9.6 KNO3 + C12H22O11 --> 4.8 K2CO3 + 7.2 CO2 + 11 H2O + 4.8 N2 (approx.)

So, 970g KNO3 and 342g sucrose, which is 74% KNO3 and 26% sucrose. This produces 662g of potassium carbonate. And, as you know, in a well made (ie, intimately mixed) LE of this type there is little slag or "pearling" left after combustion. Meaning that all 662g of potassium carbonate is dispersed as smoke (well, and droplets flung about, but largely as smoke). In other words, 50% of the mass of the charge ends up as smoke.
Increasing the amount of fuel decreases the %age of KNO3, therefore decreasing the amount of K2CO3 that can be made, reducing the max possible amount of smoke. Also, burning will be less vigorous, so it will be less well dispersed.
I think the idea to use sub-optimal amounts of oxidiser came from the common belief that "incomplete combustion produces smoke", which is not always the case...
Just be careful that you design the smoke charge not to take off or shoot about. One method is to put it into a tin can, with many holes poked in all sides for the smoke to pour out of. If you do it like this, it works well to have the smoke charge taken out of whatever you cast it into so that all surfaces are able to burn, and wrap it a few times in blackmatch to get it going well all over its surface. Or have a central core with blackmatch up that.

A fun (but not very effective or safe) smoke is the following: take approx 1 volume of fine zinc powder, and approx 2 volumes of very fine, dry ammonium nitrate powder. Take them outside, mix them at arm's length, then put a few drops of water on top.
Usually it will erupt into a big cloud of smoke, sometimes it catches fire with a barely visible flame, often you will see brown NO2 also. I'm not entirely sure what is happening, but I suspect the following occur:

Zn + 2 NH4NO3 --> Zn(NO3)2 + 2 NH3 + H2 + heat
2 NH3 + H2 + 2 O2 --> N2 + 4 H2O + heat
NH4NO3 + heat --> 2 H2O + N2O
Zn(NO3)2 + heat --> ZnO + 2 NO2 + 0.5 O2
(etc)

All the water is produced as steam which condenses into the cloud of "smoke."

[A-BOMB]

Oopps, I forgot to add this, by chemical smokes I mean you add A+B=smokes (no lighting)
like what you have for KMNo4 + glycerin, just mix them together and afew seconds later there is fire. Thanks Mr.Cool
so does anybody know what like of things have zinc in them?

[Macgyver]

Originally posted by Sparky
Certainly you've heard of the 4/6 sucrose/potassium nitrate smoke. My friend has made it many times and found that it is not actually a very effective smoke. Much of the smoke I think is water because it quickly dissipates, and the smoke does not stay on the ground well at all. A 5/5 is an improvement but stil not great.

My friend has tried this smoke with good success. His notes are included here:
White Smoke Type A, 127' (from Military and Civilian Pyrotechnics)
zinc dust 38.5
Hexachloroethene 46.5 (74.4 PVC)
ammonium chloride 3
potassium perchlorate 12


A cheaper alternative would be 47% ZnO, 47% HCE, 6% Al, but this one needs a first fire mix, for example add some of the above formula on top of it, once it gets going it burns well and produces lots of smoke....

[Sparky]

Thanks Mr. Cool for that little lesson on sugar smokes.

A-Bomb, I don't think you will find any two part mixes that spontaneously ignite and give a good amount of smoke. White phosphorous gives a good smoke but it is bad for the lungs. I think titanium chloride just has to be heated to give lots of smoke (used in the theatrical industry sometimes I think).
In Canada, pennies made after 1997 are zinc with a copper plating, but IIRC you don't live in Canada. I have looked around for zinc in normal everyday items and the only other source I could find is galvanized things which doesn't provide much zinc. You probably will have to buy it as scrap. My friend tried making zinc powder once by making zinc chloride (zinc and hydrochloric acid) then reacting that with aluminum powder. It worked OK but he never used it much because he got a chance to buy zinc dust from a pyrotechnics supplier. You can probably buy zinc oxide from the pharmacy. It is used to protect against sunburns and I think for something else too.


Before I got sidetracked, point of this post was to say that my friend tried the 5/5/2 KNO3/sucrose/paraffin mix and it worked very well. Preliminary tests suggest that it is even better than the White Smoke Type A, 127' with PVC, though it is not as handy to use (can't be packed into a tube - it won't burn). The smoke seems to rise rather fast but I'm sure that can be remedied. Since the smoke is vaporized parrafin it is not too unpleasant to breath.

[chicomalo]

US pennies made after the early 1980s are also copper-plated zinc. Zinc is used in sacraficial anodes to prevent corrosion on boats, look at a marine supply store. Another metal sometimes -- but not nearly as often -- used for this purpose is magnesium. Either way, they're useful.

[Skean Dhu]

i just saw today in lowes(for those of you stateside) an aerosol can in the electrical section labeld ' Zinc-it' galvanizing spray, on the side *danger contains zinc powder* and a bunch of petrolium distillates, i assume for quick drying and to stick onto the object you want to galvanize.

[A-BOMB]

What was the name of the spray?

[Anthony]

"Zinc-it" by the sounds of it :)

[Nepetalactone]

Hi all, this is my first post as I'm new to this Forum, but... here goes I guess!


The most efficient way to get Zinc aside from finding a place where you can get it straight is probably to use the Zinc Chloride. If you start by putting a galvanized nail or whatnot into 6M< HCl the acid 'melts' the zinc easily. I'm kind of an on-my-own newb (lab assistant) so I'm not 100% sure about availability of aluminum powder but if you couldn't find it powdered it would still be more pleasant finding a solid chunk of aluminum and sanding IT down then the measly 250,000 Zn atoms coated around a piece of galvanized steel. Galvanized metals are found everywhere (that ugly corrugated roofing, nails, construction joists) and you can go to a junk yard to find a solid chunk of aluminum to dust... (stupid pun). I don't know, sounds like the easiest way to me...

[Anthony]

I vaugely understand what you're getting at, but you really should re-think and re-phrase your post! It is unbelievably vague and disjointed...

BTW, there are a few more than 250 000 atoms on the surface of an average nail ;)

[vulture]

250 000 atoms = 4,2x10^-19 mole...

[Nepetalactone]

Sorry about the vague post, like I (kind of) said, I'm a new poster. Anyhow sorry about the 250k atoms, I meant 250,000 atoms THICK... a month or so ago I calculated the number of atoms (with accuracy to .0001 meters and .001 grams) thick galvanized Zn was and it was somewhere around 250k. Sorry about that, I guess I said what I meant and didn't mean what I said!... great now I probably got myself into more trouble. ;)

Anyhow, as for my post...

If you are planning on getting Zn by sanding dust off a chunk of galvanized metal, it would be a pain in the ass. It would be MUCH easier sanding dust off of a chunk of Al because it's easier to get in a solid piece. On the other hand, after getting the Al powder you still have to go through the trouble of melting the Zn and then isolating it with the Al... It's probably the better process for getting larger quantities of Zn only.

I hope that remedies the vagueness... (made sense when I wrote it :confused: )

~Nepetalactone

[metafractal]

A-BOMB, I would strongly suggest not trying the Chlorine + Antifreeze one. By chlorine, I take it that you mean calcium or sodium hypochlorite (NaClO/CaClO, used as pool chlorine). The main reaction occuring is a redox reaction between a hypochlorite and a liquid hydrocarbon (so FYI, the Antifreeze could be substituted for motor oil, brake fluid etc.). I once tried this mixture. Yes, this reaction does produce a lot of dense, white smoke. But this smoke is filled with Cl2 and other Cl- nasties. I was trialing a minute quantity of it in a controlled space for a Chlorine gas grenade. It is totally unsuitable for pyrotechnics. As a poor-man's occasionally lethal tear gas, however, its wonderful!

[The Crazed]

I had read somewhere that if you mixed zinc powder and sulphur together that you would get a smoke mixture and I was wondering if anyone had heared about this before and new the formula.

[chicomalo]

Mixed in a 2:1 ratio, it could probably be used as a smoke formula, although it is more commonly used as a rocket propellant.

[zaibatsu]

I've used it before (Zn/S) as a smoke comp and it works quite well, as I think all the product of the reaction are solids --> nice smoke. I've heard it's not that good a rocket propellant though, due to it being pretty heavy. Also makes a nice cracker composition for *larger* crackers... ;)

[Mr Cool]

Zn/S mixtures happen to be among my favourie things (the flame colour is great!), but the zinc gets expensive with big charges.
Makes GOOD smokes, although the smoke does have a habit of rising on the big convection current made by the very hot burning charge. But if all you want is a very fast, THICK smoke then loose Zn/S is probably the way to go. If you fill air rifle pellet tins with it and fuse them then you get a cool deep "thud", big bright flash, then blinding smoke. Very fun. And it's useful in smaller crackers too, right down to a gram or so of mixture, but it's nowhere near as good as chlorate mixtures or other common ones.
If you want to be a bit nasty, put in too much sulphur to give your smoke other blinding effects...

[jfk]

well i came into this thread looking for some new smoke mixtures, didnt find any but i did get osme good ideas about magnesium and zinc.

im going to get some of that zinc aerosol-galvanising spray, let it sit over night and then puncture the top of the can in a well ventilated area, and post back on whether just the propellent sprays out or the whether the temporary vaccum created sucks the zinc powder out as well....

as for sacrificial annodes ive paying my local chandalieres a trip to see if they have magnesium ones. (chandalieres=ship fitters)

[Macgyver]

Originally posted by zaibatsu
I've used it before (Zn/S) as a smoke comp and it works quite well, as I think all the product of the reaction are solids --> nice smoke. I've heard it's not that good a rocket propellant though, due to it being pretty heavy. Also makes a nice cracker composition for *larger* crackers... ;)

I can tell you that it works fairly well as a rocket propellant.

I made an experiment filling up a spent CO2 bottle from my CO2 gun, and just taped the thing to a stick, and it took off like a bat out of hell!

But you're absolutely right about the mix being quite heavy, filling up the CO2 bottle increased the weight of it by 30 g.

The good thing with Zn/S is that it will only generate a certain amount of pressure, if the pressure gets over that threshold, it will slow the reaction down, so given that your rocket engine is designed to handle that pressure you'll never get any rockets that explode on the ground.

I don't remember the exact pressure limit for the reaction, but I can look it up in my notes if anyone wants to know.

Took off so fast that all I saw was the trail of smoke it left behind as it traveled thru the air... One moment it was on the ground, next thing I know it's just gone!

[Guerilla]

This would more likely to belong under Zn/S Rocket thread, but anyway..

IMO Zn/S composition isn't very good in crackers at least if good bangs are wanted, they go off with VERY low boom, even in relatively big salutes I've tried. Gives a nice flash though.. But then again I would rather use something like KMnO4/Zn flashpowder for loud salutes.

In rockets, the thick smoke trails left behind look pretty cool, but I like to experiment more with chlorate and nitrate based fuels that can push the rocket to altitude :). Maybe Zn/S could be used in the end as a booster, packed after the main fuel grain.

Maybe one reason I am being so pessimistic with Zn/S because I get my sulfur from pharmacy and the price isn't too cheap. :( However, the only product that is formed is a solid zinc sulphide (sublimes at 1185C, produces 193kJ/mol) which has a relatively high molecular weight, I can't tell exactly why but this is what gives it a poor thrust.

[kingspaz]

i can tell why. its a solid! for thrust you needs lots of gas production to push your rocket along. thats why NH4ClO4 is so good, lots of gaseous products.

[vulture]

I assume that the temperature of a burning Zn/S mixture will surpass 1185C easily and thus the zincsulphide sublimes. The energy needed for this process is largely compensated by:

2ZnS + 3O₂ --> 2SO₂ + 2ZnO

So there is some gas produced and this oxidation produces a fairly large amount of energy.
However, the problem is this reaction might very well uccor outside the burn chamber because of the oxygen shortage in there.

[Guerilla]

i can tell why. its a solid! for thrust you needs lots of gas production to push your rocket along.
Yes, that sure is one chief reason, but I was rather looking for an explanation how the high molecular weight affects upon thrust..

I believe it is because of the heavier the molecule is the more it needs energy to warm. Lighter ones generate more heat than heavier ones, with a same amount of energy.

In example, the combustion products of black powder are usually CO, CO2, KOH, N2, SO2 etc.. An average molecular weight (AMW) of these will be something around 40, which is less than half that of ZnS. The released energy will raise the temperature of a light weight gas more than a heavier one, thus giving a higher exhaust velocity.

[Mr Cool]

I believe heavy exhaust gasses are bad simply because the heavier they are, the more energy they carry away with them, so the less energy ends up as KE of your rocket. I think.

[kingspaz]

Guerilla, another thing to consider is the mass of the individual gas molecules formed. a mole of CO has the same volume as a mole of CO2 at the same temperature and pressure. thus, the higher the number of gas molecules produced the better. there is a trade off though, formation of CO doesn't give out as much heat as that of CO2 so will therefore give a smaller expansion.
does that make sense?

[Guerilla]

Yes it does. Diatomic CO doesn't also need so much energy as triatomic CO2 to heat. Molecular weight isn't however the only thing that matters, MWs of H2O and N2 are 18 and 24, from this one could say that water has a better heat capacity than nitrogen because its MW is smaller, but it is vice versa. A number and a structure of atoms counts, too.

To sum all this up and considering an ideal gas output of thrust.. Combustion products should be in the lightest and simplest form as possible and the number of gas molecules as high as possible. ZnS doesn't quite fit these.

[Dark Meat]

Hey..

This is my first post, which will most likely get obvious as it goes on. Anyways my friends and I are rather interested in smoke bombs... after all, we aren't likely to explode (depending on which smoke bomb we use, of course.) Having used the Sucrose/Potassium Nitrate bomb, and having interesting results, (police swarming around public toilets. Hehe.) we thought we were set for life. Then I found this site. Comments such as "moderate smoke" and "ineffective" relating to the bomb we used have piqued my interest. So I was wondering if anyone could give instructions simple (or not simple) smoke bomb, that would be more effective than sucrose/potassium nitrate, that is prefereably cheap.. with some detail..

also is there a glossary of terms, or a list of how to make some compunds commonly referred to on this site? I have 6th form science.. which is only the second to last year of high school in new zealand.. and many things seem foreign to me. Sorry I'm so newb. :o

[Kriegsminister]

There are a lot of diffrent smoke compositions.
Take a look here: http://www.geocities.com/thejuiceuk/pfp.html
There you can download the PFP Database which has a nice selection of smoke compositions.
But most of the composition will not be as cheap as the simple KNO3/Succrose smoke and, depending on where you live and how old you are, you might have some troble aquiring the necessary chemicals.

A cheap and quite effective composition consists of 90g KN03, 90g Succrose (Sugar) and 60g Paraffin (grind up some candles). From my experience this composition gives some nice results.

Here's the topic covering this composition:
http://www.roguesci.org/theforum/showthread.php?s=&threadid=532

[Guerilla]

Try ammonium nitrate saturated newspaper rolls. Easy, cheap and I think they produce more dense smoke than KNO3/sucrose. I used to play with these in the days when I didn't have anything else..

If one has a patience to soak and dry whole big newspaper, it will spit out pretty large cloud of thick white smoke that will remain longer than KNO3/Sucrose smoke. Those have to be tightly rolled and completely dry. Sounds somewhat kewlish maybe, but worth trying.

[kingspaz]

ive found with those smoke bombs that some experimentation is required to get the right concentration of AN solution to soak the paper in. too much and it bursts into flames when lit, too little and it won;t sustain the burn. but when you get it right it does work surprisingly well.
for good smoke have a search for a thread called 'new smoke mix' or similar. the stuff works great!

[Guerilla]

I used to wrap some foil around the rolls with a small nozzle to prevent the smoke from catching fire. The nozzle makes the smoke come out with almost rocket like pressure, which also cools the smoke particles better. In calm summer day the smoke can float on ground for a fairly long time. could make a couple big ones someday, poor entertainment.. :p

Adding some NH4Cl in the solution might improve the performance making thicker smoke but probably not considerably, rather suppressing the burn rate.

[Sparky]

I just wanted to follow up on my post about the paraffin smoke.

SWIM has tried the 9/9/6 kno3/sucrose/paraffin mix a few times now and it is quite good, significantly better than the 5/5/2 mix. The opening smoke in the Forum Video by THErAPIST looks a lot like a smoke bomb using this mix (anyone know if it is?). The potassium nitrate and sucrose were both quite fine (milled KNO3 and confectioners sugar) and screened a few times to mix them well. Then the paraffin was stirred in. The soup can got a bunch of ~1/8" holes punched in it, then they were taped over and a fuse put in one of the holes. The mix was put in then compacted down and some mill dust (basically BP) put on top to make sure it lit. If the mix isn't compacted then it burns much faster of course, and it still works well but packed is preferred because of the slower burn time. Then the can was crimped shut and set on the ground to go off. The one thing I don't like about this device is that it is not throwable since it would disrupt the compacted mix and possibly some mix could fall out of the holes and not burn. I think if you could find a suitable container then it could be made throwable. Alumium cans are melted by the 5/5/2 mix, so probably by this too. The smoke has good light scattering ability and stays on the ground well. In a cloud of it at night time a flashlight actually makes it more difficult to see around you. The smoke is quite easy to breathe.

[inFinie]

in cells but NOT alkaline, casing under the cover (brand, size %0 Hg %0 Cd...) is Zn, in cell positive electrode is compressed carbon, and the black powder (not BP :) ) is MnO2{ manganese (IV) oxide } + C

And MnO2 catalyses decomposition of H2O2 violently, but i didn't tried it with KNO3