Concentrating Calcium Bicarbonate Solution

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To increase the concentration of an aqueous calcium bicarbonate solution, the use of 3A zeolite molecular sieves is considered for potassium exchange with calcium, potentially allowing bicarbonate entry. The discussion explores alternatives to potassium ions that could inhibit calcium exchange and examines other molecular sieves that selectively absorb water. Quicklime is suggested as a more efficient desiccant than silica gel for water removal. Various methods for concentrating the solution, such as evaporation, boiling, or freeze-distillation, are proposed. The conversation also touches on the tendency of calcium hydrogen carbonate solutions to precipitate calcium carbonate, raising questions about the desired solubility levels.
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I had the idea of concentrating calcium bicarbonate using zeolite, but I believe the calcium ions would be exchanged with ions in the zeolite, enlarging the pores.
I want to increase the concentration of an aqueous calcium bicarbonate solution and have considered using 3A zeolite molecular sieves. I believe such zeolite uses potassium ions to make their pores smaller and is capable of exchanging the potassium for calcium, which I believe would make the pores large enough for the bicarbonate to enter. Are there any cations of sufficient size and charge that could be used to replace the potassium and inhibit calcium exchange? Are there any other types of molecular sieves that would be able to absorb just water from such a solution? I might wind up using a reverse osmosis membrane if this is not tenable, but I want to know if this might be feasible.
 
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Scale? Do you have small samples in a lab, or are you operating a batch or continuous industrial process?
Strange_matter said:
Are there any other types of molecular sieves that would be able to absorb just water from such a solution?
"Quicklime has a high affinity for water and is a more efficient desiccant than silica gel."
https://en.wikipedia.org/wiki/Calcium_oxide
 
Baluncore said:
Scale? Do you have small samples in a lab, or are you operating a batch or continuous industrial process?

"Quicklime has a high affinity for water and is a more efficient desiccant than silica gel."
https://en.wikipedia.org/wiki/Calcium_oxide
This is small scale. I'm actually doing this at home, not in a lab, so my resources are also limited.
 
Why do you need to concentrate the calcium bicarbonate solution?
How much water do you need to remove?

You could use time to evaporate the water, or store the samples in dry air.

Simmer or boil the solution, to evaporate the water.

Maybe freeze-distil the solution, like applejack, place the samples in a freezer, then pick out the ice that forms.
https://en.wikipedia.org/wiki/Applejack_(drink)#Production
 
Calcium hydrogen carbonate solutions have the tendency to precipitate calcium carbonate.
Do you want to increase equilibrium solubility of calcium carbonate, or produce a solution supersaturated in respect of calcium carbonate?
 
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