sulphate explosive

[artificier]

someone know a good powder using only a oxidizer like a sulphate and a fuel ? I just know the MgSO4/Mg but its possible to use other sulphate like copper sulphate,ammonium sulphate etc ?

[Chemguy]

Magnesium sulfate, aluminum sulfate, K and Na are the main sulfates that are used, maybe (NH4)2SO4 too. Just do some research about water of hydration. The lower the better, but it must be anhydrous to be good. If it's low then you will be able to get rid of water faster (obviously).

[Rogue Chemist]

CaSO4 and Al, not a powder, you make a putty with it and water, allow to set, and dehydrate in an oven. Better than thermite.

[artificier]

but the CaSO4/Mg exist ??

[shadopyro]

Yes, i believe CaSO4 is plaster of paris. pretty cheap stuff and sold in DIY/art stores all around.

It'll be more effective than MgSO4, though it'll be best to use BaSO4...

 

-Say, havent you already made a post on the subject of sulphate flash powders?

[artificier]

epsom flash powder...i make this post to post ALL sulphate explosive. I find great info about sulphate !!

 

SULPHATE EXPLOSIVE

Most sulfates are not water soluble, are geologically stable

and can be easily and cheaply obtained by mining, rather

than having to be produced through complicated and expensive

chemical processing. Therefore sulfates pass the first test

for possible inclusion in any pyro formula; they are

inexpensive. Indeed native sulfates such as barite (BaSO4)

and celestite (SrSO4) are the starting materials for other

barium and strontium compounds used in fireworks.

 

Sulfates certainly appear attractive because their oxygen

content compares favorably with that of metal chlorates,

perchlorates and nitrates, as Table 1 illustrates. Also a

comparison of the heat evolved from reaction of aluminum and

various oxidizing agents again shows that sulfates compare

favorably with more familiar pyrotechnic oxidizers. (See

Table 2.)

 

Table 1

Percent oxygen contained (percent by weight) for various

pyrotechnic oxidizers and sulfates, for the anhydrous

compound.

 

Nitrate Chlorate Perchlorate Sulfate

Ammonium 0.60 0.47 0.54 0.48

Barium 0.37 0.32 0.38 0.27

Calcium 0.58 0.46 0.41 0.47

Copper 0.51 0.42 0.49 0.40

Gadolinium 0.42 0.35 0.42 0.32

Lithium 0.69 0.53 0.60 0.58

Magnesium 0.65 0.50 0.57 0.53

Potassium 0.47 0.39 0.46 0.37

Sodium 0.56 0.45 0.52 0.45

Strontium 0.45 0.38 0.45 0.47

 

Table 2

Heat produced (cal/g) from a mixture of an oxidizer or

sulfate with aluminum. Values from AMCP 706-185(1967) and/or

Vasilev (1973) (*).

 

Sodium perchlorate 2,600

Lead nitrate 1,500

Sodium chlorate 2,500

Barium nitrate 1,400

Potassium perchlorate 2,400

Cu sulfate 1,400/1,560*

Potassium chlorate 2,200

Ca sulfate 1,300/1,470*

Sodium nitrate 1,800

Na sulfate 1,200/1,360*

Potassium nitrate 1,800

K sulfate 1,200/1,180*

Lithium sulfate 1,620*

Barium sulfate 900/910*

Magnesium sulfate 1,610*

Lead sulfate 800

Ammonium nitrate 1,600

 

However, low cost is not the only criteria for selecting

oxidizers for use in fireworks compositions. A quick check

of Table 1 reveals several oxidizers with high oxygen

content, for instance, calcium, sodium, and ammonium

nitrates, sodium chlorate, and magnesium perchlorate.

However, of these only sodium nitrate has found use, albeit

limited primarily to military pyrotechnics. All of these

compounds are hygroscopic and therefore unusable in the real

world. In fact, magnesium perchlorate is used as a drying

agent under the trade name of "Anhydrone".

 

 

There can be no doubt that the largest problem concerning

the use of sulfates as oxidizing agents is their waters of

hydration, for example:

 

Na2SO4-10H2O and CuSO4-5H2O. Although the ten extra oxygen

atoms in sodium sulfate raise its total oxygen content from

45% to 70%, this extra oxygen contained in the waters of

hydration is not available for productive work. In truth it

only gets in the way, since a large amount of heat is

required to first remove the water of hydration from a

composition's outer surface before the ignition temperature

can be reached. Then once the reaction becomes self

sustaining, even more heat, produced by a burning star for

instance, will be removed from the reaction in the form of

vaporized water. (It should be noted that the latent heat of

vaporization for water is 540 calories per gram of water at

100° C. This value represents heat that must be supplied by

the pyrotechnic reaction to change water at 100° C into

steam at 100° C.) There is also the possibility, in

magnesium containing compounds, of the water vapor reacting

with the magnesium forming hydrogen and magnesium oxide,

effectively removing a large amount of fuel, with little

gain in heat. In the case of sodium sulfate decahydrate,

where 56% of each molecule is water, 31,920 calories of heat

would have to be supplied simply to remove all the water of

hydration in the form of steam from each 100 grams of

sulfate. For example, in a composition using potassium

perchlorate as the oxidizer and aluminum as the fuel, 13.3

grams of aluminum and potassium perchlorate would be needed

just to remove the water from each 100 grams of sodium

sulfate decahydrate, before any useful work (heat and/or

light) would be produced!

 

As a further complication, the temperature at which waters

of hydration are liberated varies from sulfate to sulfate,

e.g., sodium sulfate decahydrate loses all its water at 100°

C while manganese sulfate monohydrate does not lose all its

water until the temperature reaches 400-450° C! And to

really complicate things, manganese(II)sulfate can exist as

either mono, tri-, tetra, penta, hexa, or heptahydrate!

Although the tetrahydrate is the most common form.

 

However, US Patent 2,885,277 claims to make use of the

waters of hydration in magnesium sulfate heptahydrate,

MgSO4-7H2O (Epsom salts), to produce hydrogen gas when the

sulfate is reacted with magnesium. It is further claimed

that this combination will function as either a torch or a

salute. It would be well to note that Ellern (1968, p. 272)

expresses doubt concerning the safety and utility of such

mixtures.

 

The use of sulfates as oxidizers suffers from yet another

problem. As Dr. Conkling (in press) has pointed out "In

pyrotechnics, the solid liquid transition appears to be of

considerable importance in initiating a self propagating

reaction. The oxidizing agent is frequently the key

component in such mixtures, and a ranking of common

oxidizers by increasing melting point bears a striking

resemblance to the reactivity sequence for these materials."

Unfortunately the melting point of most sulfates is much

higher than either chlorates, perchlorates or nitrates. Only

four sulfates (manganese, copper, zirconium and iron) have

melting points below that of barium nitrate, and these four

are well hydrated (tetra or penta). Melting points are

summarized in Table 3.

 

 

Table 3

Melting point for various anhydrous oxidizers and sulfates.

Values are from the CRC Handbook. d decomposes, sd slight

decomposition.

 

Copper perchlorate 82

Ag perchlorate 486

Iron perchlorate >100d

Thorium nitrate 500

Strontium chlorate 120d

Th perchlorate 501

Lithium chlorate 128

Ba perchlorate 505

Scandium nitrate 150

Sr nitrate 570

Manganese(III) sulfate 160d

Ba nitrate 592d

Americium nitrate 170

Zn sulfate 600

Copper sulfate 200sd 650d

Th(I) sulfate 632

Silver chlorate 230

Silver sulfate 652

Lead chlorate 230

Mn(II) sulfate 700

Lithium perchlorate 236

Lithium sulfate 845

Sodium chlorate 248

Nickel sulfate 848

Magnesium perchlorate 251d

Sodium sulfate 884

Lithium nitrate 264

Ytterbium(III) sulfate 900

Calcium perchlorate 270

Yttrium sulfate 1000

Sodium nitrate 307

Cesium sulfate 1010d

Rubidium nitrate 310

Rubidium sulfate 1060d

Potassium nitrate 334d

Potassium sulfate 1069

Calcium chlorate 340

Samarium sulfate (basic) 1100

Potassium chlorate 356

Magnesium sulfate 1124d

Potassium perchlorate 400d

Lanthanum sulfate 1150

Zirconium sulfate 410d

sulfate 1170d

Cesium nitrate 414

Calcium sulfate 1450

Barium chlorate 414

Barium sulfate 1480

Iron sulfate 480d

Sr sulfate 1605d

Sodium perchlorate 482

 

It is evident that getting compositions based on sulfates as

oxidizers to ignite while not impossible ... is not going to

be easy. There can be no doubt that it is going to take an

extremely hot ignition source!

 

Copper sulfate with its low melting point looks like a prime

candidate but again, the water of hydration is a problem.

Exposed to moist air, CuSO4 becomes CuSO4-H2O, and when

wetted, CuSO4-5H2O. Also, because copper sulfate is water

soluble, it is seldom found in native form (chalcanthite).

Therefore it is manufactured from copper metal and sulfuric

acid, and as a result fails the first test, it is not cheap.

It is also not safe with chlorates.

 

Although certainly attracting because of their low cost

oxygen content, sulfates have for the most part, not been

employed as oxidizing agents. However, them have found their

niche in strobe formulas.

 

Vander Horck (1974) reported on several formulas using

calcium and copper sulfates demonstrated to him by Bob

Winokur who later (Winokur, 1974) made additional comments

about them. Further Dr. Shimizu (1981) presents several

strobe ("twinkler") formulas using sulfates, i.e.,

strontium, barium, sodium and calcium. Advantage is taken of

the great difficulty of igniting and then sustaining

ignition in sulfate based compositions. Therefore flashes of

light are produced each time the sulfate reaches its melting

point or decomposition temperature, burning commences and

shortly thereafter extinguishes only to repeat, producing

the strobe light effect.

 

Sulfates have long been used in color flame compositions

more for their metal than oxygen content. However, for the

most part, the color produced by sulfate based compositions

not containing metal fuels such as aluminum or magnesium,

will be found to be less than satisfactory, since only metal

fuels are capable of producing the high temperatures

necessary to melt or decompose most sulfates. The use of

various sulfates is detailed below:

 

Copper sulfate: In older literature, e.g. Kentish (1878)

compositions for blue flames can be found using copper

sulfate and potassium chlorate, where the copper ion is used

to produce the blue color. THIS COMBINATION IS DANGEROUS.

Safer and more effective blue formulations are available.

 

Barium sulfate: Troy Fish (1981) recommends the use of

barium sulfate in parlon bound green stars. He notes that as

a result of barium sulfate's extreme insolubility (0.000413

grams per 100 ml of boiling water!), it is one of the few

nontoxic barium compounds. I have been able to locate only

seven formulas using barium sulfate, and all seven use

either magnesium, aluminum or magnalium.

 

Calcium sulfate: Despite the many obstacles noted above,

calcium sulfate hemihydrate (plaster of Paris) [CaSO4-

1/2H2O] has been used as an oxidizer in fireworks and

pyrotechnics: In combination with sodium and barium nitrate

in white light compositions (Ellern, 1968, formulas 36, 37

and 38), as an incendiary when combined with aluminum (US

Patent 2,424,937, Vol. 3 of the "Black Book", 1982), or

aluminum and magnesium sulfate (US Patent 4,381,207), and

when compounded with aluminum, Teflon, and sulfur (US Patent

4,349,396) as a metal cutting torch.

 

Calcium sulfate combined with either aluminum or magnesium

has been suggested as a "flash report" mixture! (Sanford,

1974)

 

This sulfate is found in pink tableau fire or star

compositions using potassium perchlorate as the oxidizing

agent. Weingart (1947) has the only modern for

mula I have been able to locate that uses calcium sulfate

without either aluminum, magnesium or magnalium.

 

Potassium sulfate: The Technico Chemical Receipt Book 1896

long ago recommended the use of potassium sulfate in blue

compositions. There is only one modern formula using

potassium sulfate, Dr. Shimizu's white "twinkler" using

magnalium as the metal fuel.

 

Strontium sulfate: This sulfate had long ago been used in

the production of red or purple flames. However, there are

no formulas using strontium sulfate in Lancaster, Ellern or

Weingart. There are however, three "twinkler" formulas in

Shimizu using strontium sulfate. All three contain

magnalium.

 

Sodium sulfate: I have been able to locate only four

formulas using sodium sulfate, all by Dr. Shimizu, who uses

sodium sulfate in combination with magnalium for yellow

strobe stars.

 

Manganese sulfate: Perhaps the most interesting use of

sulfate is the addition of manganese sulfate (MnSO4 H2O) to

aluminum sodium nitrate flare compositions. Farnell et

al.(1972) discovered that this compound alters "the

decomposition of sodium nitrate to form oxides of nitrogen

rather than its normal decomposition products of nitrogen

and oxygen." This change results in a 55% decrease in

burning rate, a 155% increase in luminous output, and a 466%

increase in luminous efficiency!

 

Although not a mainstays of the fireworks trade, sulfates

have found employment along with the proverbial kitchen

sink, used frying pans, oil of spike and philosopher's

wool!!!

[Mumbles]

You know, you could at least give credit where it is due.

[asilentbob]

Bump, found sources. Not like many people have read this topic, but meh. Completeness.

 

"Literature cited

AMCP 706185, 1967, Engineering Design Handbook, MilitaryPyrotechnics SeriesPart 1; Theory and Application. NTIS AD 817071.Black Book, 1982, Improvised Munitions Black Book, Vol. 3.Desert Publications.Conkling, J., (in press), The Chemistry of Pyrotechnics andExplosives: Basic Principles and Theory. Marcel Dekker, NewYork.CRC Handbook of Chemistry and Physics, 1981, 62nd edition.Ellern, H., 1968, Military and Civilian Pyrotechnics.Chemical Publishing Inc., NY.Fish, T., 1981, Green and other colored flame metal fuelcompositions using parlor. Pyrotechnica Vll, pp. 2537.Farnell, Westerdahl and Taylor, 1972, The Influence ofTransition Metal Compounds on the AluminumSodium Nitrate Reaction. Third International PyrotechnicsSeminar.Kentish, T., 1887, The Pyrotechnists Treasury, The CompleteArt of FireMaking. Chatto and Windus, London.Sanford, R., 1974, Plaster of Paris flash powders, AmericanPyrotechnist Fireworks News, p. 527.The Technico Chemical Receipt Book 1896.Merck Index, 1983, The Merck Index: An Encyclopedia ofChemicals, Drugs, and Biologicals. Merck and Co., 10thedition.Shimizu, T., 1981, Fireworks: The Art, Science, andTechnique. Maruzen Publishing Co.US Patent 2,424,937, July 1947, Incendiary Composition.US Patent 2,885,277, May 1959, Hydrogen Gas GeneratingPropellant Compositions.US Patent 4,349,396, September 1982, MetalCutting Pyrotechnic Composition.US Patent 4,381,207, April 1983, Pyrotechnic Composition.Valsilev, A.A., et al., 1973, Combustion of mixtures ofmetal sulfates with magnesium or aluminum. Translated fromRussian. NTIS AD 785988, 5 pp.Vander Horck, M.P., 1974, Unconventional star compositionsdemonstrated. American Pyrotechnist Fireworks News, 7(4),issue no. 76, p. 506.Weingart, G. W., 1947, Pyrotechnics. Chemical PublishingCo., NY, pages 61 and 134.Winokur, R., 1974, More on unconventional stars. AmericanPyrotechnist Fireworks News, 7(5), issue no. 77, p. 516."