What Is in Road Flares?

For extraction, you'd want to use different solvents that have different dissolving properties - usually something like water, ethanol, DCM, acetone, MEK, methanol, toluene or whatever.

For strontium, it looks like it's relatively soluble in short chain alcohols (methanol/ethanol) compared to the other two, so you'd crash out the potassium perchlorate by dissolving the mixture in water, then reducing the temperature to cause perchlorate to drop out of solution, then mix in a moderate amount of methanol to crash the potassium nitrate out, being left with a reasonably pure strontium nitrate, that you could then hot filter and recrystallize in anhydrous methanol if you wanted >90% purity. One or two rounds of recrystallization will leave you in the high nineties, probably above 97%.

This is a classic chemistry workup kind of problem and there are interesting engineering challenges embedded in it.

Of course... practical people just buy technical grade strontium nitrate and make fireworks out of it directly, as the article says.

This page reads like an exasperated response to constant discussions and requests for how to extract strontium nitrate from road flares, and emphasizes that it is hard and pointless in the first place. I never noticed such discussions, but maybe it's outside of my bubble! Quite an amusing read nonetheless.

>Some older flare formulations also had things such as pitch, asphalt, wax, tallow, potassium chlorate and black powder. Those are not likely to be part of modern flare formulations.

Most of the formulations in the table have charcoal, potassium nitrate or other oxidiser, and sulfur. Surely, to say they don't contain black powder is semantics, when they contain the ingredients of black powder?

I'm missing some context here: Why do we want to extract strontium nitrate anyway?

Um... some context? What even are road flares? And why would I want to extract strontium nitrate from them?