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Romix
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NaOAc, KOAc and K2CO3.
Any ideas on how to separate Na(Ac), K(Ac) and K2CO3?
If it's impossible will just dilute it and feed to plants...
About 350ml of solution, at least 150grams of K2CO3 there, lots of K(Ac) and Na(Ac) keeps falling out of the solution evaporating it slowly on a
lamp...
[Edited on 9-5-2023 by Texium]
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Romix
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What alkali Acetates, Sodium and Potassium, decomposes to at high temperatures of MAPP+ torch.
Can I poison my self, breathing the decomposition products on fresh air?
Had an accident decomposing some organic copper salt, and it took my breath away for like 3-5 minutes, thought I will die from suffocation. Kind of
same feeling like falling from big height on your back.
In theory, decomposition products of Sodium might be much less soluble then Potassium's. In theory!
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Romix
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Tried decomposing sample on a spoon, no noticeable smell was coming off in a decomposition, some visible Carbon formed.
[Edited on 4-9-2023 by Romix]
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Rainwater
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Potassium carbonate wiki
Potassium acetate wiki
sodium acetate wiki
Without spoon feeding you an answer, try reviewing the properties of each compound, specifically looking for something you can exploit to seperate
them.
Melting points
Boiling points
Solubility in different solvents
It looks like seperation of the sodium acetate from the potassium compounds will be stright forward and simple.
"You can't do that" - challenge accepted
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Romix
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Please tell me, how?
[Edited on 4-9-2023 by Romix]
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teodor
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You probably can easily separate K2CO3 and Na/K acetate (acetate is soluble in many organic solvents and K2CO3 is not), but Na/K separation usually
doesn't worth the efforts.
As far as I know plants don't like Na, so I doubt you can make anything useful from your mixture, except to make mixed Na/K acetate by adding acetic
acid just to remove K2CO3, than you can use it the same way as Na or K acetate, usually it doesn't matter which cation, I mean when you need either Na
or K acetate you always can substitute one with another, so the mixture will also work.
[Edited on 4-9-2023 by teodor]
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Rainwater
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Read this
[Edited on 4-9-2023 by Rainwater]
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Romix
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Thanks!
But nothing there about mentioned salts.
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j_sum1
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Yeah. But you could look up the Ksp values and apply the same method.
There are enough hints in this thread to point you in the right direction.
Bottom line is that you will be able to precipitate carbonates by use of an appropriate organic solvent.
You will not be able to easily separate sodium ions from potassium ions.
Sodium ions are not much good for plants, but potassium ions will be helpful for them. This potentially puts a limit on the usefulness of your ash.
Considering that your ask comes from plants, it should not have sodium ions in such a great quantity to cause problems.
It is not too clear what your objective is here. Do you wish to practice the chemistry, or are you just wanting to recycle the ash. If the latter,
dilute sufficiently, apply to plants and see what happens.
If you want to learn some chemistry then be prepared to do some reading and calculations of your own. Plenty of people will help but no one wants to
do the work for you.
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clearly_not_atara
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Sodium and potassium can be separated to a surprisingly large degree by the use of oxalate. Potassium oxalate is very soluble, while sodium oxalate is
one of the least soluble sodium salts. I don't know if oxalate affects plant growth.
The more pessimistic observation: would it be at all worth it to try any of these separation methods, oxalate, organic solvents, etc, when we are
talking about recovering some relatively cheap salts anyway?
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RU_KLO
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try looking here (solubility chart) https://en.wikipedia.org/wiki/Solubility_chart
one possibility:
Add Calcium chloride solution, dropwise until no more precipitate is formed.
this will probably precipitate Calcium Carbonate from K2CO3.
CaCl2 + K2CO3 -> CaCO3 (precipitates) + 2KCl
filter to remove CaCO3
I don t know how will CaCl2 reacts with acetates, but acetates and Chlorides from K, Ca, Na are all soluble.
then maybe adding HCl to convert everything to Chloride and use solubility tables to check which will precipitate first.
from these, it seems that CaCl2 is the most soluble, so Na K chloride will precipitate first.
Go SAFE, because stupidity and bad Luck exist.
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Texium
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Fixed that title for you. OAc is acetate, while Ac is merely acetyl. Huge difference between sodium acetate and acetylsodium...
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Romix
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Quote: Originally posted by RU_KLO  | try looking here (solubility chart) https://en.wikipedia.org/wiki/Solubility_chart
one possibility:
Add Calcium chloride solution, dropwise until no more precipitate is formed.
this will probably precipitate Calcium Carbonate from K2CO3.
CaCl2 + K2CO3 -> CaCO3 (precipitates) + 2KCl
filter to remove CaCO3
I don t know how will CaCl2 reacts with acetates, but acetates and Chlorides from K, Ca, Na are all soluble.
then maybe adding HCl to convert everything to Chloride and use solubility tables to check which will precipitate first.
from these, it seems that CaCl2 is the most soluble, so Na K chloride will precipitate first.
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Thank you for the reaction, didn't knew about it, will try it out some day.
But what's the point of this reaction? Adding another cation to the mix, that's all.
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RU_KLO
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| Quote: Originally posted by Romix | | Quote: Originally posted by RU_KLO | try looking here (solubility chart) https://en.wikipedia.org/wiki/Solubility_chart
one possibility:
Add Calcium chloride solution, dropwise until no more precipitate is formed.
this will probably precipitate Calcium Carbonate from K2CO3.
CaCl2 + K2CO3 -> CaCO3 (precipitates) + 2KCl
filter to remove CaCO3
I don t know how will CaCl2 reacts with acetates, but acetates and Chlorides from K, Ca, Na are all soluble.
then maybe adding HCl to convert everything to Chloride and use solubility tables to check which will precipitate first.
from these, it seems that CaCl2 is the most soluble, so Na K chloride will precipitate first.
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Thank you for the reaction, didn't knew about it, will try it out some day.
But what's the point of this reaction? Adding another cation to the mix, that's all.
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trying to answer: "how to separate Na(Ac), K(Ac) and K2CO3"
if you want to separate diferent subtances from a solution, or you try using "fisical" methods (solubility, destilation, maybe electrolisis) without
adding new elements or you add "something" to promote separation.
Go SAFE, because stupidity and bad Luck exist.
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Rainwater
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I will try to show you how I would think through the problem.
Im leaving out a bunch of stuff to keep this simple.
We will form a hypothesis and work through the numbers and process and try to predict a result.
You can read this in any text book, but if your like me, you need to hear the same think 3 different ways before it sticks.
To purify by recrystallization or percipitation
Start by listing the solubility of each component in a solution.
The sciencemadness wiki usually gives you the solubility for different common solvents.
The wiki trys to list at least 1 solvent that has a large change in temperature.
One solvent that has a small change in temperature
and one solvent that is insoluble
Water, alcohol, ether, acetone are commonly listed because of their ability to meet these requirements over a wide range of compounds
image source
1) The solvent with a large change in temperature, is great for purification via recrystallization or "selective precipitation"
2) Solvents with solubility that does not change much with temperature or are insoluble are good for "selective extraction"
3) Solvents which your target compound are insoluble are good for selective extraction and 4) selective precipitation
Example 1) extracting KCl from NaCl solution - recrystallization
NaCl has a solubility in water which is not changed much by temperature
KCl has a solubility in water which changes with temperature alot compared to NaCl
With this information, we can hypothesis that if you take a mixture of the 2 salts in an unknown ratio, and mix it with hot water, the resulting
solution will contain a fixed amount of NaCl, and a variable amount of KCl.
Continuing the hypothesis, by changing the tempature of the solution, we can vary the amount of KCl in solution.
This is a simple overview. In truth, the amount of both salts in solution will change with temperature,
Between 0c and 100c we can expect the NaCl to change from 35g to 40g per 100ml of water
Between 0c and 100c we can expect the KCl to change from 25g to 55g per 100ml of water
These numbers are not exact, but close +/- 5g/100ml
If this hypothesis is true, we can expect a 100c saturated solution of these salts to cool to 0c and produce a percipitate that is enriched in KCl
If the data in the chart is accurate, we can expect 100ml of 100c saturated salt solution, to cool to 0c and produce a percipitate containing 5g NaCl
and 30g of KCl
Now we have a known ratio of mixed salts.
we can hypothesis that if we add the correct amount of solvent to our sample, we can keep all the NaCl in solution and extract the most KCl possible.
Suppose that we made a large quantity of mixed salts that are at a ratio of 5g/NaCl and 30g/KCl or better stated as 1g/NaCl and 6g/KCl
We hypothesis 100ml of 100c solution will hold 55g of KCl
We hypothesis 100ml of 0c solution will hold 35g of NaCl
We want to disolive as much of our salt mixture as possible, without exceding the limit of NaCl that will remain in solution.
So now we have a simple logic problem
Easiest method for me to solve this problem is iteration
We want to see which limit is reached first.
If we add 7g of the mixed salt, that will give us 1g/NaCl and 6g/KCl, by repeating the iteration
| Code: |
1g/NaCl and 6g/KCl
2g/NaCl and 12g/KCl
3g/NaCl and 18g/KCl
4g/NaCl and 24g/KCl
5g/NaCl and 30g/KCl
6g/NaCl and 36g/KCl
7g/NaCl and 42g/KCl
8g/NaCl and 48g/KCl
9g/NaCl and 54g/KCl
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We have reached the upper limit of how much KCl will dissolve into solution at 100c per 100ml of water with 9 iterations. 9 * 7g = 63 grams of mixed
salts
By dissolving 63g of the mixed salt at 100c, then cooling to 0c we expect to get a percipitate of pure KCl.
Looking at the amount of of salts disolved and the expected solubility changes, we can expect the solution to contain 9g of NaCl and 25g of KCl and
the percipitate to consists of 29g of KCl (54g-25g=29g)
Removing the percipitate and restarting the iterations from the current solution composition we can add more of our mixed salt for the next step.
| Code: |
9g/NaCl and 25g/KCl - starting solution
10g/NaCl and 31g/KCl - 1st addition
11g/NaCl and 37g/KCl
12g/NaCl and 43g/KCl
13g/NaCl and 49g/KCl
14g/NaCl and 55g/KCl
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7g * 5 iterations = 35g of mixed salts
By adding 35g of the mixed salts, we hypothesis that our solution at 100c will have a composition of 14g/NaCl and 55g/KCl
Then by cooling to 0c, the solubility of KCl will drop and we will have a solution composition of 14g/NaCl and 25g/KCl with a percipitate composed of
30g/KCl
Repeating this same process again we get
| Code: |
14g/NaCl and 25g/KCl - starting solution
15g/NaCl and 31g/KCl - 1st addition
16g/NaCl and 37g/KCl
17g/NaCl and 43g/KCl
18g/NaCl and 49g/KCl
19g/NaCl and 55g/KCl
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5 iterations again. And again by chilling the solution to 0c, you can expect another 30g of KCl percipitate and 25g to remain in solution
We can now hypothesis that this process can be repeated until the concentration of the NaCl reaches its solubility limit.
By repeating the cycle 3 more times we can conclude that the solution once chilled to 0c will have a composition of 34g/NaCl and 25g KCl.
Example 2) extracting NaCl from KCl solution - selective extraction
Using the results from example 1,
You may be thinking that we have only extracted and purified KCl, but the fact is were where doing both at the same time.
We have been consentrating both products, one in solution, the other in percipitate
Now that we have a saturated solution of NaCl in our hypothesis, lets see what happens when we try to run another cycle of recrystallization.
You add in another 35g of the mixed salt into our solution at 100c.
This time it all does not disolve, the solution is saturated with NaCl and simply can not hold any more NaCl. But it can hold KCl.
Now if you change the procedure a little and filter off this undisolive solid, while hot, you have a solid enriched in NaCl, continue with the
procedure as we have been(cool, filter)
The KCl now has NaCl percipitating with it in measurable amounts. Remimber the first percipitation we theorized about?
5g/NaCl and 30g/KCl can be expected.
Repeating this process will isolate the NaCl from each addition of mixed salt.
Example 3) selective extraction
This example I will have to use different compounds.
Supose you wanted to extract salts from sand. The sand is insoluble in water, so the process is stright foward. But suppose some of your salts are
incased in the sand( or other insoluble compound) and the solvent cant reach it. This is called entrapment.
Example 4) selective percipitation
Let's mix 2 reagents to form a product. Epson salt and sodium carbonate
MgSO4aq + Na2CO3aq = MgCO3s + Na2SO4aq
The solubility of MgCO3 is very low, so this produced a solid percipitate
Example 5)
This example is the most complicated out of the group. Here we are going to change the solvent, instead if just water, we will add something else.
For example, seperation of sodium carbonate and water.
Sodium carbonate is soluble in water but not in acetone.
By adding acetone to the solution, the solubility of the salt decreases.
Summary
Hopefully this will help you understand the other material that has been offered, if you haven't realized yet that example number three is the
solution to the original post, good luck. There are many different things in play that I did not mention to keep this post as simple as I could. But
search for different solvents, and the solubility of your target compounds .
[Edited on 6-9-2023 by Rainwater]
[Edited on 6-9-2023 by Rainwater]
[Edited on 7-9-2023 by Rainwater]
"You can't do that" - challenge accepted
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MadHatter
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Separating Compounds
https://en.wikipedia.org/wiki/Solubility_table
The link above points to a more useful solubility table.
The CaCl2 is an excellent 1st step because CaCO3 is nearly insoluble in water.
From opening of NCIS New Orleans - It goes a BOOM ! BOOM ! BOOM ! MUHAHAHAHAHAHAHA !
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Texium
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Ca(OAc)2 would be better since it will keep everything as the acetate rather than introducing chloride ions. Better yet though, just add
acetic acid to convert any carbonate present to acetate without adding any additional cations or anions to worry about. Why has that not been
suggested yet?
@Romix if you come back with yet another asinine spoonfeeding request after all the help people have tried to offer, this thread is getting binned.
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teodor
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| Quote: Originally posted by Texium | | Better yet though, just add acetic acid to convert any carbonate present to acetate without adding any additional cations or anions to worry about.
Why has that not been suggested yet? |
 it has been already suggested, but the thread is so overblown that this is hard
to see
[Edited on 6-9-2023 by teodor]
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Romix
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K2CO3 started falling out of the solution on slow evaporation on a lamp straight after the NaOAc porridge, massive and with visible crystal form,
possible to capture.
Both salts are hygroscopic, meaning melting if stored or drying on fresh air by moisture in the air.
[Edited on 9-9-2023 by Romix]
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Romix
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Crystals grown in one night, pure 99% K2CO3, before I broke them down in to smaller pieces.
There's a similarity, sure!!
[Edited on 9-9-2023 by Romix]
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Romix
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Yes, they are identical, crystals grew bigger...
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Romix
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What will happen to Acetates of Alkali metals if I add weak HCl to the salt?
If anions will displace each other, what theoretically could happen.
Or I'll just do next batch of plant ash in HCl instead of Vinegar.
I can electrolyze Chlorides of Alkali metals, using Graphite electrodes specially made for electrolysis(used them for couple of days making NaOH and
mixture of acids containing Chlorine, they not breaking and falling in to solution) but if they will, will it be safe to boil solution containing
KClO3 with fallen in it Graphite, I know that it explodes with Carbon. How about Graphite and solved in water KClO3? Also I have long Titanium
electrodes, may they be better? What glue would you recommend to me to stick the electrodes in a lid of a reactor where electrolysis will take place.
Graphite electrodes could just be melted in to the lid, Titanium ones will need gluing because they are mesh. Also what polymer be best to for
Chlorine outlet?
[Edited on 26-11-2023 by Romix]
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Romix
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This video gave me this idea, what you guys think, is it possible?
https://www.youtube.com/watch?v=CqMEnrQb5q8&embeds_refer...
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B(a)P
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| Quote: Originally posted by Romix | What will happen to Acetates of Alkali metals if I add weak HCl to the salt?
If anions will displace each other, what theoretically could happen.
Or I'll just do next batch of plant ash in HCl instead of Vinegar.
I can electrolyze Chlorides of Alkali metals, using Graphite electrodes specially made for electrolysis(used them for couple of days making NaOH and
mixture of acids containing Chlorine, they not breaking and falling in to solution) but if they will, will it be safe to boil solution containing
KClO3 with fallen in it Graphite, I know that it explodes with Carbon. How about Graphite and solved in water KClO3? Also I have long Titanium
electrodes, may they be better? What glue would you recommend to me to stick the electrodes in a lid of a reactor where electrolysis will take place.
Graphite electrodes could just be melted in to the lid, Titanium ones will need gluing because they are mesh. Also what polymer be best to for
Chlorine outlet?
[Edited on 26-11-2023 by Romix] |
There is no problem having carbon particles with your dissolved chlorate. You just need to add a filtration step once you have everything dissolved
up.
I have used two part epoxy in the past with good results for glueing in electrodes for an electrolysis cell.
I am not sure what is going to happen if you undertake electrolysis with acetate ions present. If it were me I would get a working cell using pure
reagents before I started to add other unknowns. Acetate will for ethane via electrolysis under the right conditions and with chloride in the mix who
knows what would happen.
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Romix
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Ok, decomposing KClO3 to KCl and heating it directly with MAPP+. Can Chlorate explode in this scenario?
Or is it better to heat up sides or bottom of a crucible not letting flame touch the Chlorate?
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