megalomania
June 22nd, 2003, 02:31 PM
Tony Montana
Frequent Poster
Posts: 145
From: Australia
Registered: JUN 2001
posted 07-06-2001 08:06 PM
--------------------------------------------------------------------------------
I was reading a patent, to be precise:
PATENT NO.5,250,687
Process For Preparation Of RDX.
In which they say; "Waste acetic acid formed during the reaction is re-condensed and subjected to an energy intensive ketone process being thereby, converted back to useful acetic anhydride."
Does anybody know what an energy intensive ketone process involves?
If they have to re-condense the acetic acid, this would mean vinegar would be a good substitute that could be condensed. And condensed vinegar could then be subjected to the energy intensive ketone process, yielding acetic anhydride. Is this possible without too much hassle??????
Anthony
Moderator
Posts: 2383
From: England
Registered: SEP 2000
posted 07-06-2001 08:09 PM
--------------------------------------------------------------------------------
Yes that is how acetic anhydride is made, try a search as the process has been covered in detail before.
10fingers
Frequent Poster
Posts: 415
From: USA
Registered: SEP 2000
posted 07-13-2001 10:24 PM
--------------------------------------------------------------------------------
Ketene is made by passing acetone vapors through a chrome/iron pipe at high temperatures and then leading the ketene into a container of glacial acetic acid to form acetic anhydride.
I've seen the exact procedure posted here before and it can be found in one of the Kitchen Improvised Plastic Explosives manuals.
I have never heard of anyone trying this process and I am curious if it works.
[This message has been edited by 10fingers (edited July 13, 2001).]
cutefix
Frequent Poster
Posts: 330
From: california
Registered: MAY 2001
posted 07-14-2001 02:57 AM
--------------------------------------------------------------------------------
That procedure is feasible in an industrial setting , but for laboratory scale I doubt if anybody will exert effort to recycle his spent acetic acid,when he has more important things to do.
The acetic acid waste is more stronger than normal home vinegar(5-10 % acid),other food processingl vinegars reach to 20%. But still lesser than about 40% or more concentration found in that spent acids.It may be theoretically feasible to convert household or food grade vinegars to acetic anhydride but not a practical,or economical idea.
10fingers
Frequent Poster
Posts: 415
From: USA
Registered: SEP 2000
posted 07-14-2001 09:09 AM
--------------------------------------------------------------------------------
The process may be practical for someone has access to glacial acetic acid but not acetic anhydride.
I once tried to make glacial acetic acid from vinegar. I neutralized the vinegar with sodium bicarbonate to make sodium acetate, dried it in the oven to remove all water and distilled the sodium acetate from sulfuric acid. I obtained some strong acetic acid (80%), but it was not glacial because it would not freeze. I distilled it again under vacuum but it was still not pure. Don't know why.
The whole process was a lot of work and I don't recommend it.
Frequent Poster
Posts: 145
From: Australia
Registered: JUN 2001
posted 07-06-2001 08:06 PM
--------------------------------------------------------------------------------
I was reading a patent, to be precise:
PATENT NO.5,250,687
Process For Preparation Of RDX.
In which they say; "Waste acetic acid formed during the reaction is re-condensed and subjected to an energy intensive ketone process being thereby, converted back to useful acetic anhydride."
Does anybody know what an energy intensive ketone process involves?
If they have to re-condense the acetic acid, this would mean vinegar would be a good substitute that could be condensed. And condensed vinegar could then be subjected to the energy intensive ketone process, yielding acetic anhydride. Is this possible without too much hassle??????
Anthony
Moderator
Posts: 2383
From: England
Registered: SEP 2000
posted 07-06-2001 08:09 PM
--------------------------------------------------------------------------------
Yes that is how acetic anhydride is made, try a search as the process has been covered in detail before.
10fingers
Frequent Poster
Posts: 415
From: USA
Registered: SEP 2000
posted 07-13-2001 10:24 PM
--------------------------------------------------------------------------------
Ketene is made by passing acetone vapors through a chrome/iron pipe at high temperatures and then leading the ketene into a container of glacial acetic acid to form acetic anhydride.
I've seen the exact procedure posted here before and it can be found in one of the Kitchen Improvised Plastic Explosives manuals.
I have never heard of anyone trying this process and I am curious if it works.
[This message has been edited by 10fingers (edited July 13, 2001).]
cutefix
Frequent Poster
Posts: 330
From: california
Registered: MAY 2001
posted 07-14-2001 02:57 AM
--------------------------------------------------------------------------------
That procedure is feasible in an industrial setting , but for laboratory scale I doubt if anybody will exert effort to recycle his spent acetic acid,when he has more important things to do.
The acetic acid waste is more stronger than normal home vinegar(5-10 % acid),other food processingl vinegars reach to 20%. But still lesser than about 40% or more concentration found in that spent acids.It may be theoretically feasible to convert household or food grade vinegars to acetic anhydride but not a practical,or economical idea.
10fingers
Frequent Poster
Posts: 415
From: USA
Registered: SEP 2000
posted 07-14-2001 09:09 AM
--------------------------------------------------------------------------------
The process may be practical for someone has access to glacial acetic acid but not acetic anhydride.
I once tried to make glacial acetic acid from vinegar. I neutralized the vinegar with sodium bicarbonate to make sodium acetate, dried it in the oven to remove all water and distilled the sodium acetate from sulfuric acid. I obtained some strong acetic acid (80%), but it was not glacial because it would not freeze. I distilled it again under vacuum but it was still not pure. Don't know why.
The whole process was a lot of work and I don't recommend it.