well then with KNO3 (purchased of eBay for around £3)
Material Required
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Potassium Nitrate (2 parts by volume)
CONCENTRATED sulfuric acid (1 part by volume) Motor vehicle batteries
Industrial plants
2 bottles or ceramin jugs (narrow necks are
preferable)
Pot or frying pan
Heat source (wood, charcoal, or coal)
Tape (paper, electrical, masking, but NOT cellophane!)
Paper or rags
IMPORTANT: If sulfuric acid is obtained from a motor vehicle battery,
concentrate it by boiling it UNTIL white fumes appear. DO NOT INHALE FUMES
NOTE: The amount of nitric acid produced is th same as the amount of
potassium nitrate. Thus, for two tablespoons of nitric acid, use 2
tablespoons of potassium nitrate and 1 tablespoonful of concentrated sulfuric
acid.
Procedure:
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1) Place dry potassium nitrate in bottle or jug. Add sulfuric acid. Do not
fill the bottle more than 1/4 full. Mix until paste is formed.
CAUTION: DO NOT INHALE FUMES!
2) Wrap paper or rags around necks of two bottles. securly tape necks of two
bottles together. Be sure that bottles are flush against each other and that
there are no air spaces.
3) Support bottles on rocks or cans so that empty bottle is SLIGHTLY lower
than bottle containing paste so that nitric acid that is formed in receiving
bottle will not run into other bottle.
4) Build fire in pot or frying pan.
5) Gently heat bottle containing mixture by gently moving fire in and out. As
red fumes begin to appear periodically pour cool water over empty receiving
bottle. Nitric acid will befin to form in receiving bottle.
CAUTION: Do not overheat or wet bottle containing mixture or it may shatter.
As an added precaution, place bottle to be heated in heat resistant container
filled with sand or gravel. Heat this outer container to produce nitric acid.
6) Continue the above process until no more red fumes are formed. If the
nitric acid formed in the receiving bottle is not clear (cloudy) pour it into
cleaned bottle and repeat steps 2-6.