Quick Composition Test - Nitrate/Salicylate Compositions

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Date: 2005-02-03


Two quick tests of Sodium Salicylate and Potassium Nitrate composition, one with Sulfur, one without:


70 Potassium Nitrate

30 Sodium Salicylate


52 Potassium Nitrate

27 Sodium Salicylate

10 Sulfur

Prepared by ball milling ~ 10g amounts in my mini-mill for about 20 minutes.

A small quantity ~ 0.2 g charged in 5 mm ID, 50 mm long tubes, fused with a short length of blackmatch.


The purpose of these experiments was not "nitrate whistle" despite the "NW" naming of the composition. I was looking for a good charcoal replacement in BP.

The "NW" composition burnt quite quickly with a shrill rushing sound. Oddly like damp Benzoate Whistle, but no where near as good (if you are looking for an easy perchlorate-free whistle don't bother). However observing the spectrogram there is the characterstic whistle curve hidden in the wideband noise, better milling and firmer pressing might produce a weak but usable whistle.

The "NSW" burnt somewhat slower with drossy sparks that made quite a nice effect for the simplicity of the composition and device construction.

The NSW composition is based on the following nieve stoichiometric reaction. The thermodynamics are probably quite different:

18(KNO3) + 11(S) + 4(C7H5O3Na) => 28(CO2) + 9(N2) + 10(H2O) + 2(Na2S) + 9(K2S)

Similarly the NW is based on this reaction:

56(KNO3) + 10(C7H5O3Na) => 37(CO2) + 28(N2) + 25(H2O) + 5(Na2CO3) + 28(K2CO3)


title type size
NW Test video/x-msvideo 1.075 Mbytes
NSW Test video/x-msvideo 902.114 kbytes
Testing Stand image/jpeg 29.489 kbytes
Spectrogram of NW Burn image/jpeg 159.131 kbytes