Concentrating Calcium Bicarbonate Solution

[Strange_matter]

TL;DR

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.

 

[Baluncore]

Scale? Do you have small samples in a lab, or are you operating a batch or continuous industrial process?

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

 

[Strange_matter]

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.

 

[Baluncore]

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

 

[snorkack]

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?