Double displacement of Sodium/potassium carbonate and calcium hydroxcide

[Dexterity]

I know I need to use a 1:1 molar amount. BUT calcium hydroxcide is BARELY soluble in water, so instead of using lime water...will milk of lime work?

Like I make a milk of lime slurry with 1 mole calcium hydroxcide THEN add one mole of sodium or potassium carbonate...and stir for a while and wait for the calcium carbonate to drop out...

Will this work and produce sodium hydroxcide, which is souble in water. Then I just decant or filter out the precipitation?

[exchemist]

6 hours ago, Dexterity said:

I know I need to use a 1:1 molar amount. BUT calcium hydroxcide is BARELY soluble in water, so instead of using lime water...will milk of lime work?

Like I make a milk of lime slurry with 1 mole calcium hydroxcide THEN add one mole of sodium or potassium carbonate...and stir for a while and wait for the calcium carbonate to drop out...

Will this work and produce sodium hydroxcide, which is souble in water. Then I just decant or filter out the precipitation?

I'm not familiar with milk of lime. Isn't it just another word for lime water?   

[studiot]

2 hours ago, Dexterity said:

I know I need to use a 1:1 molar amount. BUT calcium hydroxcide is BARELY soluble in water, so instead of using lime water...will milk of lime work?

Like I make a milk of lime slurry with 1 mole calcium hydroxcide THEN add one mole of sodium or potassium carbonate...and stir for a while and wait for the calcium carbonate to drop out...

Will this work and produce sodium hydroxcide, which is souble in water. Then I just decant or filter out the precipitation?

Solubility constant for calcium carbonate is 1000 time less than for calcium hydroxide, so yes you will remove some calcium carbonate and be left with a sodium carbonate solution, sightly enriched with sodium hydroxide.

How are you going to unmix that ?

[chenbeier]

It was (is) a common process before electrolysis was invented.

https://www.elettronicaveneta.com/en/prodotto/cb-in-103-ev-preparation-of-sodium-hydroxide-by-caustification-of-carbonate/

 

[KJW]

9 hours ago, exchemist said:

I'm not familiar with milk of lime.

I think it's like eye of newt. Welcome to the alchemy forum.

 

 

16 hours ago, Dexterity said:

I know I need to use a 1:1 molar amount. BUT calcium hydroxcide is BARELY soluble in water, so instead of using lime water...will milk of lime work?

Like I make a milk of lime slurry with 1 mole calcium hydroxcide THEN add one mole of sodium or potassium carbonate...and stir for a while and wait for the calcium carbonate to drop out...

Will this work and produce sodium hydroxcide, which is souble in water. Then I just decant or filter out the precipitation?

The problem with trying to react undissolved calcium hydroxide is that the solid particles tend to become coated with insoluble calcium carbonate, preventing further access of the calcium hydroxide to the carbonate solution.

 

[Dexterity]

1 hour ago, KJW said:

I think it's like eye of newt. Welcome to the alchemy forum.

 

 

The problem with trying to react undissolved calcium hydroxide is that the solid particles tend to become coated with insoluble calcium carbonate, preventing further access of the calcium hydroxide to the carbonate solution.

 

So what is the remedy for this? Should I boil the milk of lime? 

11 hours ago, exchemist said:

I'm not familiar with milk of lime. Isn't it just another word for lime water?   

Lime water is clear. Milk of lime is a white solution that will clear if allowed to settle.

[chenbeier]

Boil the solution, after cool down filter it, so you get a saturated solution. Settle down is also option, but difficult to decant the solution.

[KJW]

16 minutes ago, Dexterity said:

Should I boil the milk of lime?

The solubility of Ca(OH)₂ decreases with temperature. However, heat may speed up the equilibration.

 

 

16 minutes ago, Dexterity said:

So what is the remedy for this?

The solubility of CaCO₃ is actually not very low (0.013 g/L @ 25 °C, although it will be lower in Na₂CO₃ solution), so the problem I mentioned above may not be as much of a problem as I had suggested. I think heating the mixture with stirring will eventually complete the reaction. In a laboratory setting, one could use a Soxhlet extractor to extract Ca(OH)₂ into the flask containing the Na₂CO₃ solution, though this is probably overkill.

 

[Dexterity]

35 minutes ago, KJW said:

The solubility of Ca(OH)₂ decreases with temperature. However, heat may speed up the equilibration.

 

 

The solubility of CaCO₃ is actually not very low (0.013 g/L @ 25 °C, although it will be lower in Na₂CO₃ solution), so the problem I mentioned above may not be as much of a problem as I had suggested. I think heating the mixture with stirring will eventually complete the reaction. In a laboratory setting, one could use a Soxhlet extractor to extract Ca(OH)₂ into the flask containing the Na₂CO₃ solution, though this is probably overkill.

 

Maybe I should use heat. THIS is the way to make it without heat. The famous chemist and physican Paracelsus used his own recipe for alkahest was made of caustic lime, alcohol, and carbonate of potash.

The lime and potassium carbonate would turn into potassium hydroxcide.

[studiot]

2 hours ago, chenbeier said:

It was (is) a common process before electrolysis was invented.

Electrolysis preparation is apparantly more common in the US than the UK. I do not know about Europe or other places.

 

[Dexterity]

9 hours ago, KJW said:

The solubility of Ca(OH)₂ decreases with temperature. However, heat may speed up the equilibration.

 

 

The solubility of CaCO₃ is actually not very low (0.013 g/L @ 25 °C, although it will be lower in Na₂CO₃ solution), so the problem I mentioned above may not be as much of a problem as I had suggested. I think heating the mixture with stirring will eventually complete the reaction. In a laboratory setting, one could use a Soxhlet extractor to extract Ca(OH)₂ into the flask containing the Na₂CO₃ solution, though this is probably overkill.

 

Have you done a double displacment before. This seems pretty straight forward.