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Greetings fellow nerds.
So in this video we’re going to make luminol.
It’s pretty easy to make using lab chemicals like
3-nitrophthalic acid, hydrazine and sodium dithionite.
But as an added challenge, we’re not going to start there,
instead we’re going to make luminol entirely from chemicals
that can be found domestically in hardware stores, supermarkets and pharmacies.
For safety reasons I’m still going to use my lab equipment though.
To get to luminol we’re going to start with vinyl gloves made from poly vinyl chloride.
These contain diethylhexyl phthalate.
To extract it we cut it up and boil it with some rubbing alcohol.
After a quick filtration we now we have a solution of diethylhexyl phthalate in isopropanol.
We now convert it to phthalic acid by first adding water
and sodium hydroxide based drain cleaners.
The mixture is boiled for an hour or two and then allowed to cool.
It’ll separate into two layers,
the disodium phthalate will be in the bottom aqueous layer
and all the alcohols will be on the top.
Separating out just the bottom layer, we then add some hydrochloric acid.
This converts the disodium phthalate into phthalic acid and sodium chloride salt.
The phthalic acid precipitates out after several hours.
Now we convert it to phthalic anhydride and purify it
by heating it on the hot plate to 300 Celsius.
The phthalic anhydride boils and then solidifies against this flask of cold water.
Periodically we scoop it out for collection.
Now we have pure phthalic anhydride.
To nitrate it, we mix it with sulfuric acid based drain cleaner
along with sodium nitrate that we made in a previous video
from instant cold packs and sodium hydroxide based drain cleaner.
Then we carefully heat the mixture for 2 hours.
Afterward we let it cool and dissolve the resulting mixture of products into water.
Leaving it overnight the 3-nitrophthalic acid precipitates out and we separate that by filtration.
Now we condense it with hydrazine,
but first we need to make that from methyl ethyl ketone,
ammonia, bleach and sulfuric acid as we showed in a previous video.
We also need to get sodium acetate trihydrate that we made in another video.
Once we have all our ingredients we mix together the 3-nitrophthalic acid,
the hydrazine sulfate, and the sodium acetate trihydrate along with a little water.
We boil the mixture first to dissolve everything and then further to dry it.
For the second stage of the reaction we get brake fluid
containing polyethylene glycol that has a boiling point greater than 230 Celsius.
Adding that to the mixture we can now heat it much higher and drive the reaction forward.
We’re almost done and now we need to convert that nitro group into an amine.
To do that we first dissolve everything in sodium hydroxide
and then add sodium metabisulfite.
This is sold as a disinfectant for home brewing and as a stump remover.
Now we get some aluminum foil and jam it into beaker,
holding it down with a flask while it reacts.
This finally produces luminol.
We’re not done yet.
The luminol is still mixed in with this large amount of by products and contaminants.
To purify we first filter off all the excess aluminum and aluminum oxides.
Then we prepare a mixture of the swimming pool chemical sodium bisulfate,
along with water and acetone.
Adding everything together the luminol dissolves in the liquid
while most of the wastes precipitate out.
The luminol solution is carefully decanted off.
And then allowed to dry for a few days.
The resulting cake is broken up and some water is added
to dissolve any remaining salts but not the luminol.
The slurry is filtered and allowed to dry.
To test it we can dissolve a tiny amount in water and first check for fluorescence.
Luminol exhibits a very strong blue fluorescence in water.
Then for the ultimate test we add bleach to it with the lights off.
That flash of light proves the presence and activity of luminol.
Another test is to mix the luminol with dimethyl sulfoxide muscle rub and sodium hydroxide,
this gives a much longer lasting green glow.
So there we have it,
it took a lot of work but we made luminol entirely using domestically available chemicals.
Sure it cost thousands of times more than buying it directly
but our objective here is to explore the science.
Thanks for watching the abridged guide.