Seperation of sodium and potassium carbonates

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The discussion centers on the separation of sodium and potassium carbonate from plant ashes, specifically questioning the solubility of sodium carbonate in ethanol. It is noted that potassium carbonate is not soluble in ethanol, leading to the suggestion of using 200 proof ethanol for separation. Participants highlight that sodium and potassium salts have similar solubility in water, complicating their separation. Crown ethers are proposed as a potential method for distinguishing between the two cations, though concerns about their cost and toxicity are raised. The solubility of both carbonates in water is discussed, with potassium carbonate being significantly more soluble than sodium carbonate. There is skepticism regarding the presence of carbonates in ashes, as carbonates decompose under heat, but it is clarified that carbonates can form from oxides or hydroxides absorbing CO2 over time. The conversation includes references to traditional methods of extracting potash from plant ashes and suggests further research through historical texts for more detailed procedures.
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I want to separate sodium and potassium carbonate from the ashes of plants. My question is, Is sodium carbonate soluble in ethanol? I know that potassium carbonate is not so could i put the mixture into 200 proof ethanol and separate the two?
 
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Only a guess but sodium and postassium salts are going to have very similair solubility in anything.
 
Depending on the composition of your plant ashes, you may want to consider using crown ethers to separate your carbonates; specifically 15-crown-5 for your sodium and 18-crown-6 for the potassium carbonate.

Edit: If it does not interfere with your procedure, consider adding a strong base to deprotonate any groups (e.g., substituted ammoniums) that could otherwise inhibit the ethers' solvation of your cations.
 
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Basically, just remember, L S, B C L, S P A
All potassium,nitrate salts are soluble.. however, chlorides,carbonates and sulphates are an exception.For chlorides, all chlorides are soluble except lead chloride and silver chloride..all sulphates are soluble except barium sulphate,chloride sulphate and lead sulphate..for carbonates,sodium,potassium and ammonium carbonate is soluble while the rest are insoluble.. as as sodium and potassium are very reactive when reacted with water due to the reactive series of metals..u can separate sodium and potassium with their solutions by titration, changing them into a oxide or hydroxide...
 
Lucas_SG said:
Basically, just remember, L S, B C L, S P A
All potassium,nitrate salts are soluble.. however, chlorides,carbonates and sulphates are an exception.For chlorides, all chlorides are soluble except lead chloride and silver chloride..all sulphates are soluble except barium sulphate,chloride sulphate and lead sulphate..for carbonates,sodium,potassium and ammonium carbonate is soluble while the rest are insoluble.. as as sodium and potassium are very reactive when reacted with water due to the reactive series of metals.
As sodium and potassium salts have similar solubilities in aqueous solution, consider a solvent that can distinguish between either cation (try crown ethers)
Lucas_SG said:
u can separate sodium and potassium with their solutions by titration, changing them into a oxide or hydroxide...
This makes no sense.
 
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Solubility of potassium carbonate is 111 grams per 100 mL of water.
Solubility of sodium carbonate is 30.7 grams per 100 mL of water.
In a saturated solution, which would precipitate out first with careful drying and chilling?

Crown ethers are wicked expensive and toxic as *ell.
 
JGM_14 said:
I want to separate sodium and potassium carbonate from the ashes of plants. My question is, Is sodium carbonate soluble in ethanol? I know that potassium carbonate is not so could i put the mixture into 200 proof ethanol and separate the two?

I ain't real certain carbonates are there in the first place. Not if it's "ashes" as in ashes left over from a fire. Carbonate decomposes with heat to form carbon dioxide. It's why sodium bicarbonate smothers fire.

Somebody correct me if this is wrong.

Jeff Corkern
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Consider the following as a statement of logic and rank it as "True" or "False."

"If people possesses immortal souls, it should be possible to deduce this by logical analysis of their behavior."

www.theninepointfivetheses.blogspot.com
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Ya both carbonates are present in ashes. Na2CO3 predominates in sea plants and K2CO3 in land plants IIRC. This is an old school preparation of potash and is outlined in scores of old textbooks. Use Google books to help you- you'll get more info there than anyone on this forum can give!

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Backyard Chemistry
 
Cesium said:
Ya both carbonates are present in ashes. Na2CO3 predominates in sea plants and K2CO3 in land plants IIRC. This is an old school preparation of potash and is outlined in scores of old textbooks. Use Google books to help you- you'll get more info there than anyone on this forum can give!

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Ah, so.

I stand corrected.
 
  • #10
Even if only the oxided or hydroxides were produced during burning, they absorb CO2 from the air and slowly convert to the carbonates.
 
  • #11
same with calcium oxide
 
  • #12
I wondered how you could form carbonates in a fire . . .


Jeff Corkern
--------------------------------------------------------------------------------------
Consider the following as a statement of logic and rank it as "True" or "False."

"If people possesses immortal souls, it should be possible to deduce this by logical analysis of their behavior."

www.theninepointfivetheses.blogspot.com
--------------------------------------------------------------------------------------
 
  • #13
how about a reaction with an acid then seperation
 
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