Concentrating ammonia
Jim, Wed Apr 12 2006, 11:57PMI made a very small apparatus for concentrating extremely minute amounts of household ammonia. It was a glass tube, blown into a bulb, and bent in half so that it could be used to distill the household solution. I tried it, but I condensed the vapor into a copper vessel, and subsequently I noticed a deep blue solution instead of the normal clear ammonia. When I tried re-distilling the solution, there was a copper-colored residue left in the bottom of the bulb. Any ideas as to if the residue is Cu (s)? What's the best method to go about concentrating very small amounts of NH3?
Re: Concentrating ammonia
Wolfram, Thu Apr 13 2006, 12:23AM
The deep blue color you observed was propably because of a tetraaminocopper complex.
I'd guess that the residue is metallic copper, I don't see what else it could be.
Wolfram, Thu Apr 13 2006, 12:23AM
The deep blue color you observed was propably because of a tetraaminocopper complex.
I'd guess that the residue is metallic copper, I don't see what else it could be.
Re: Concentrating ammonia
Bored Chemist, Thu Apr 13 2006, 11:28AM
I agree that it's probably copper. There may be some Cu2O mixed with it- you might not notice the yellow/ orange oxide in with the brownish reddish metal.
Why do you want to redistill ammonia solution anyway? It's not an easy distillation- the ammonia comes off first as a gas and won't condense easily.
For very small amounts the best bet is probably to add an acid- say HCl, dry the salt down, then add NaOH to give a concentrated solution of NH3 in salt-water. Then distill the ammonia out of this and collect it in a small amount of water.
Bored Chemist, Thu Apr 13 2006, 11:28AM
I agree that it's probably copper. There may be some Cu2O mixed with it- you might not notice the yellow/ orange oxide in with the brownish reddish metal.
Why do you want to redistill ammonia solution anyway? It's not an easy distillation- the ammonia comes off first as a gas and won't condense easily.
For very small amounts the best bet is probably to add an acid- say HCl, dry the salt down, then add NaOH to give a concentrated solution of NH3 in salt-water. Then distill the ammonia out of this and collect it in a small amount of water.
Re: Concentrating ammonia
Wolfram, Thu Apr 13 2006, 04:14PM
Check in your local hardware store, I don't know if it's usual in America, but here they sell 25% ammonia solution.
Wolfram, Thu Apr 13 2006, 04:14PM
Check in your local hardware store, I don't know if it's usual in America, but here they sell 25% ammonia solution.
Re: Concentrating ammonia
govtcontact, Sun Apr 16 2006, 04:02PM
If your trying to get NH3, its best to condense it around -33 C since it turns to a gas above that. For your condenser, use dry-ice and acetone bath...Place NaOH pellets into a sealed container that is connected to your condensor by a length of tubing, with a section of drying agent, that makes a large inverted U shape (about a 6 foot arch). This will help keep H2O our of your final NH3. Slowely drip in your H2O/NaOH solution. You should start to see what you look for...
But think about what you are trying to do...Hundreds of people have been killed in recent years doing what you plan. NH3 is not something to tinker with, and death by NH3 makes having your sexual reproduction bits torn off by a meat grinder
a less painful way out!!
govtcontact, Sun Apr 16 2006, 04:02PM
If your trying to get NH3, its best to condense it around -33 C since it turns to a gas above that. For your condenser, use dry-ice and acetone bath...Place NaOH pellets into a sealed container that is connected to your condensor by a length of tubing, with a section of drying agent, that makes a large inverted U shape (about a 6 foot arch). This will help keep H2O our of your final NH3. Slowely drip in your H2O/NaOH solution. You should start to see what you look for...
But think about what you are trying to do...Hundreds of people have been killed in recent years doing what you plan. NH3 is not something to tinker with, and death by NH3 makes having your sexual reproduction bits torn off by a meat grinder
a less painful way out!!Print this page