There is a rotary machine dedicated to making this kind.
You can search on Google and you will find them.
just write (double color rotary tablet machine)
can you explain more :
Cooling the solution( which is 90% oils) to what temperature?
When stirring, will the oil separate from the ephedrine?
Is it stirring when all the ethanol has evaporated?
Do you mean that I make the solution evaporate to half and then put it in the fridge so that the layer of oils collects on top and then I dispose of it?
I did this method.
When the alcohol begins to evaporate I see white powder.
But when I let it dry, I found a lot of oils.
Yield: 10% ephedrine, 90% oil.
Any advice ?