Amphetamine purification by acid-base extraction
- Thread starter G.Patton
- Start date
Easy, follow above procedure and replace the acid in the end.Amph. HCl is hygroscopic and will spoil fast, not something you do, unless you wanna smoke it on the spot.
Can I do this? Can you explain to me?
1. You must obtain 1 mol of amphetamine-free base (1) by adding amphetamine salts to a 20% NaOH aqueous solution to pH 12, mixing for 15 min and extracting. Amphetamine-free base by DCM or gasoline ether 3 x 75 ml.
2.HCL gas bubbles
1. You must obtain 1 mol of amphetamine-free base (1) by adding amphetamine salts to a 20% NaOH aqueous solution to pH 12, mixing for 15 min and extracting. Amphetamine-free base by DCM or gasoline ether 3 x 75 ml.
2.HCL gas bubbles
Have you read Extraction topic, man? First of all, you have to read about Extraction theory. I wrote this topic to avoid such questions. Also, Drying of Organic Liquids have to push your mind to a correct thinking way.
@G.Patton I added amph to water with a 1:1 ratio as your guidelines here and my top layer is transparent. Does transparency indicate purity or less pure?
Also I touched the solutions out of curiosity and noticed that my bottom layer has an oily texture whereas the top layer dries upon contact like alcohol. I used Petroleum Ether to separate the layers but I’m a little bit confused because of the texture.
Also I touched the solutions out of curiosity and noticed that my bottom layer has an oily texture whereas the top layer dries upon contact like alcohol. I used Petroleum Ether to separate the layers but I’m a little bit confused because of the texture.
- By G.Patton
Hello, amph sulphate is dissolved completely in water. I don't know what did you get as top layer, it isn't amphetamine. Petroleum ether isn't soluble in water and won't extract amphetamine salt. You have to separate this admixture oil and get amph free base with NaOH aq solution addition. Then, you can extract the base by Petroleum ether. Hope you'll understand me well.
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I proceeded to follow the rest of the step as outlined and I managed to get purified amph salt back. It's probably because I put a small amount of amph salt to test out this extraction procedure. I do have one question for the last step though, as I add H2SO4 the amph salt started to crystallize, I tested a small sample by adding more sulphuric acid than supposed to just to see what would happen. The crystals disappeared and it turned into a red-colored solution.
if I don't add enough H2SO4, then some crystals won't crystallize whereas if I add too much, it disappears and becomes red. So question is, how do I know how much H2SO4 to add for maximum yield?
if I don't add enough H2SO4, then some crystals won't crystallize whereas if I add too much, it disappears and becomes red. So question is, how do I know how much H2SO4 to add for maximum yield?
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If only there was a standardized measurement of acid conc. in solution that you could test for instantly and easily, damn, what a shame, someone should invent this.