Velzee
Hazard to Others
Posts: 381
Registered: 19-8-2015
Location: New York
Member Is Offline
Mood: Taking it easy
|
|
Urea from Urea Oxalate?
I planned to extract the urea found within a fertilizer I had lying around for a few years(MSDS: http://www.homedepot.com/catalog/pdfImages/ad/ad5195a6-ad3b-... ); since alcohol extraction would yield poor results, I chose to use Oxalic
acid(as I have two pounds of this stuff) to precipitate out the urea in the form of urea oxalate. The next step of this procedure would be to add it
to a sodium bicarbonate solution, leaving the urea in solution and precipitating some some sodium oxalate. My problem is, that sodium oxalate would
still remain dissolved, and I currently only prepared ~15 grams or so of urea, so I want the best quality I can get using this method.
My question is, is there another way to isolate urea from this compound, or must I go with the NaHCO3 method?
Btw, here's a photo of some of the urea oxalate I synthesized:
Check out the ScienceMadness Wiki: http://www.sciencemadness.org/smwiki/index.php/Main_Page
"All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident."
—Arthur Schopenhauer
"¡Vivá Cristo Rey!"
—Saint José Sánchez del Río |
|
|
Praxichys
International Hazard
Posts: 1063
Registered: 31-7-2013
Location: Detroit, Michigan, USA
Member Is Offline
Mood: Coprecipitated
|
|
You could try adding calcium carbonate to precipitate calcium oxalate, leaving a urea solution.
|
|
|
Velzee
Hazard to Others
Posts: 381
Registered: 19-8-2015
Location: New York
Member Is Offline
Mood: Taking it easy
|
|
Hmm.. The only reasonable source of calcium carbonate I have is around 30 grams of coral I collected from the beach. Do you suggest any other method?
Check out the ScienceMadness Wiki: http://www.sciencemadness.org/smwiki/index.php/Main_Page
"All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident."
—Arthur Schopenhauer
"¡Vivá Cristo Rey!"
—Saint José Sánchez del Río |
|
|
hissingnoise
International Hazard
Posts: 3940
Registered: 26-12-2002
Member Is Offline
Mood: Pulverulescent!
|
|
| Quote: | | The only reasonable source of calcium carbonate I have is around 30 grams of coral I collected from the beach. Do you suggest any other method?
|
Just use slaked lime . . . ?
|
|
|
Hawkguy
Hazard to Others
Posts: 326
Registered: 10-10-2014
Location: British Columbia (Canada eh!)
Member Is Offline
Mood: Body is Ready
|
|
Maybe something with Urea Nitrate? I read about that in a different thread somewhere...
|
|
|
macckone
Dispenser of practical lab wisdom
Posts: 2168
Registered: 1-3-2013
Location: Over a mile high
Member Is Offline
Mood: Electrical
|
|
Calcium chloride + urea oxalate -> calcium oxalate (precipitate) + urea hydrochloride
eliminating the hydrochloric acid will require a hydroxide that produces a chloride
with a much different solubilty from urea.
|
|
|
inkling3
Harmless
Posts: 1
Registered: 22-1-2016
Member Is Offline
Mood: No Mood
|
|
Quote: Originally posted by macckone  | Calcium chloride + urea oxalate -> calcium oxalate (precipitate) + urea hydrochloride
eliminating the hydrochloric acid will require a hydroxide that produces a chloride
with a much different solubilty from urea. |
Would calcium hydroxide not accomplish the same thing, and result in the pure Urea in water, and not the HCl salt?
|
|
|
Velzee
Hazard to Others
Posts: 381
Registered: 19-8-2015
Location: New York
Member Is Offline
Mood: Taking it easy
|
|
Sadly, I was only able to make ~4 grams of CaCO3. I've no other reasonable amounts of calcium. Another method is needed—any ideas?
@Hawkguy , could you perhaps link that thread to me? I did a quick search and I didn't really find anything of interest involving urea nitrate.
Check out the ScienceMadness Wiki: http://www.sciencemadness.org/smwiki/index.php/Main_Page
"All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident."
—Arthur Schopenhauer
"¡Vivá Cristo Rey!"
—Saint José Sánchez del Río |
|
|
diggafromdover
Hazard to Self
Posts: 84
Registered: 24-2-2015
Location: New Hampshire
Member Is Offline
Mood: Inconherent
|
|
CaCO3 is chalk, play sand from Home Despot, or lawn lime left in the air too long. If you start at Calais and swim north, you just may encounter
some.
Enjoying second childhood with REAL chemistry set.
|
|
|
The Volatile Chemist
International Hazard
Posts: 1981
Registered: 22-3-2014
Location: 'Stil' in the lab...
Member Is Offline
Mood: Copious
|
|
Here's a good a place as any to say that urea can be found in pet-safe driveway salt. Just figured this out. It's in grains, and is usually
uncontaminated.
|
|
|
mayko
International Hazard
Posts: 1218
Registered: 17-1-2013
Location: Carrboro, NC
Member Is Offline
Mood: anomalous (Euclid class)
|
|
Magnesium oxalate is also fairly insoluble in water (1 part in 1500, says Merck.)
I just ran across this report, which says oxalate is decomposed by hydrogen peroxide to CO2. Urea also reacts to form urea peroxide, but you might be
able to get this byproduct to regenerate urea through spontaneous or catalyzed decomposition of the peroxide adduct to water and oxygen.
http://web.ornl.gov/info/reports/1981/3445605762877.pdf
al-khemie is not a terrorist organization
"Chemicals, chemicals... I need chemicals!" - George Hayduke
"Wubbalubba dub-dub!" - Rick Sanchez
|
|
|
deltaH
Dangerous source of unreferenced speculation
Posts: 1663
Registered: 30-9-2013
Location: South Africa
Member Is Offline
Mood: Heavily protonated
|
|
I was reading the same report mayko lol
|
|
|
mayko
International Hazard
Posts: 1218
Registered: 17-1-2013
Location: Carrboro, NC
Member Is Offline
Mood: anomalous (Euclid class)
|
|
Heh, checking out the wiki?
http://www.sciencemadness.org/smwiki/index.php/Oxalic_acid
al-khemie is not a terrorist organization
"Chemicals, chemicals... I need chemicals!" - George Hayduke
"Wubbalubba dub-dub!" - Rick Sanchez
|
|
|
macckone
Dispenser of practical lab wisdom
Posts: 2168
Registered: 1-3-2013
Location: Over a mile high
Member Is Offline
Mood: Electrical
|
|
| Quote: Originally posted by inkling3 | | Quote: Originally posted by macckone | Calcium chloride + urea oxalate -> calcium oxalate (precipitate) + urea hydrochloride
eliminating the hydrochloric acid will require a hydroxide that produces a chloride
with a much different solubilty from urea. |
Would calcium hydroxide not accomplish the same thing, and result in the pure Urea in water, and not the HCl salt? |
calcium hydroxide is not soluble enough to do this easily.
it would work but it is slow and tedious.
|
|
|
Velzee
Hazard to Others
Posts: 381
Registered: 19-8-2015
Location: New York
Member Is Offline
Mood: Taking it easy
|
|
I attempted the H2O2 method, which did not seem to have any effect on the urea oxalate. I then attempted (with the same solution) the Na2CO3 method,
which, overnight, yeilded some crystals (which I assume to be sodium oxalate). I do not know if I should boil down the solution or let it evaporate.
I am trying to convert the rest of the fertilizer to urea oxalate, and then attempt the MgCO3 method, but after what @macckone stated, I do not
believe that this would work.
[Edited on 2/1/2016 by Velzee]
Check out the ScienceMadness Wiki: http://www.sciencemadness.org/smwiki/index.php/Main_Page
"All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident."
—Arthur Schopenhauer
"¡Vivá Cristo Rey!"
—Saint José Sánchez del Río |
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
