Organikum
resurrected
Posts: 2329
Registered: 12-10-2002
Location: Europe
Member Is Offline
Mood: busy and in love
|
|
Sodium benzoate to benzoic acid
Thats a question.
Any suggestions or better tried & true ways to produce halfway clean benzoic acid from sodium benzoate? Quick & dirty, purity is no big issue
as the benzoic acid will be used in a dry distillation lateron (as iron salt).
Yes I know, look it up, and you are right, but I have no time, I am in the process of moving and at the new place there is no way of experimenting at
all. But I got formic acid and I really would love to give the ferric benzoic & formic acid salts -> benzaldehyde a shot as I have all the
equipment here (and the howto in my head) from the benzene making.
regards
/ORG
[Edited on 15-2-2007 by Organikum]
|
|
|
YT2095
International Hazard
Posts: 1091
Registered: 31-5-2003
Location: Just left of Europe and down a bit.
Member Is Offline
Mood: within Nominal Parameters
|
|
dissolve all you can in water then add HCl soln, a ppt will form, filter and wash well.
there`s your benzoic acid.
\"In a world full of wonders mankind has managed to invent boredom\" - Death
Twinkies don\'t have a shelf life. They have a half-life! -Caine (a friend of mine)
|
|
|
Nicodem
Super Moderator
Posts: 4230
Registered: 28-12-2004
Member Is Offline
Mood: No Mood
|
|
Is this a trick question? 
Just dissolve in the minimum amount of warm water (it is well soluble, 63g/100ml at 20°C), then add one equivalent of 20% hydrochloric acid. Left
standing until it cools down and vacuum filer the crystalline mass. Wash the filter cake a couple of times with cold water to remove as much NaCl as
possible and air dry. There will be some contamination with NaCl but I don't think it will bother for your use.
Never did this though.
Edit: Been too late 
[Edited on 15-2-2007 by Nicodem]
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
|
|
|
Organikum
resurrected
Posts: 2329
Registered: 12-10-2002
Location: Europe
Member Is Offline
Mood: busy and in love
|
|
Thanks.
At the moment you best regard me as the friendly retard living next door... 
[Edited on 15-2-2007 by Organikum]
|
|
|
YT2095
International Hazard
Posts: 1091
Registered: 31-5-2003
Location: Just left of Europe and down a bit.
Member Is Offline
Mood: within Nominal Parameters
|
|
I know what it`s like moving house, the pressure sucks and you forget the most fundemental of things, yer cool 
\"In a world full of wonders mankind has managed to invent boredom\" - Death
Twinkies don\'t have a shelf life. They have a half-life! -Caine (a friend of mine)
|
|
|
garage chemist
chemical wizard
Posts: 1803
Registered: 16-8-2004
Location: Germany
Member Is Offline
Mood: No Mood
|
|
The precipitate of benzoic acid is very voluminous. If the sodium benzoate solution is too concentrated the solution will solidify upon acidification,
making filtration difficult.
One method is to acidify the solution while it is boiling hot and then let it cool down. This forms larger crystals.
Or just use a diluted sodium benzoate solution- the solubility of benzoic acid in cold water is very low, you won't loose too much product if the
solution volume is large.
|
|
|
Organikum
resurrected
Posts: 2329
Registered: 12-10-2002
Location: Europe
Member Is Offline
Mood: busy and in love
|
|
Danke Herr Garage!
Now we are getting somewhere, it seems to be trickier in reality then on paper
What I suspected.
Yields are not so important I have a lot of sodium benzoate and it was cheap and I have to use it or move it.
/ORG
|
|
|
BromicAcid
International Hazard
Posts: 3227
Registered: 13-7-2003
Location: Wisconsin
Member Is Offline
Mood: Rock n' Roll
|
|
I had no problem with suction filtration making my benzoic acid from a solution of room temperature sodium benzoate.
|
|
|
contrived
Hazard to Self
Posts: 56
Registered: 9-3-2007
Location: Washington State
Member Is Offline
Mood: skeptical
|
|
what to do with it
I have a lot of benzoic acid too. So now what? What can one do with it?
|
|
|
joeflsts
Hazard to Others
Posts: 226
Registered: 14-1-2006
Member Is Offline
Mood: No Mood
|
|
Methyl Benzoate
You could make methyl benzoate or ethyl benzoate - both nice smelling esters.
Joe
|
|
|
Magpie
lab constructor
Posts: 5939
Registered: 1-11-2003
Location: USA
Member Is Offline
Mood: Chemistry: the subtle science.
|
|
I bought some sodium benzoate that someone was selling as a preservative for carp bait. I bought it for only one reason: to make benzene. Benzene is
a useful precursor for many aromatic compounds.
The single most important condition for a successful synthesis is good mixing - Nicodem
|
|
|
contrived
Hazard to Self
Posts: 56
Registered: 9-3-2007
Location: Washington State
Member Is Offline
Mood: skeptical
|
|
so what do you do now, heat the stuff in diphenyl ether? oh there's a catalyst that needs to be there too, isn't there? seems a hard way to get
benzene but after the price I last paid.. maybe this is the way to go ...
|
|
|
not_important
International Hazard
Posts: 3873
Registered: 21-7-2006
Member Is Offline
Mood: No Mood
|
|
| Quote: | Originally posted by contrived
so what do you do now, heat the stuff in diphenyl ether? oh there's a catalyst that needs to be there too, isn't there? seems a hard way to get
benzene but after the price I last paid.. maybe this is the way to go ... |
http://www.sciencemadness.org/talk/viewthread.php?tid=4902
http://www.sciencemadness.org/member_publications/benzene_pr...
|
|
|
Magpie
lab constructor
Posts: 5939
Registered: 1-11-2003
Location: USA
Member Is Offline
Mood: Chemistry: the subtle science.
|
|
| Quote: |
seems a hard way to get benzene but after the price I last paid.. maybe this is the way to go ...
|
It is a hard way to get benzene. I have since found a source at a reasonable price so will be buying it. But Na benzoate can always serve as a
backup should benzene become unavailable.
The single most important condition for a successful synthesis is good mixing - Nicodem
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
