Sciencemadness Discussion Board

Recovering caesium carbonate from caesium bicarbonate

Keras - 17-5-2023 at 09:45

Folks,

I plan to try a reaction which involves the transformation of caesium carbonate into caesium bicarbonate in its mechanism. Caesium carbonate in not horribly expensive, but it would be nice if I could recover at least part of it from the ashes of the reaction.

If I use NaOH (or KOH) directly to raise the pH, I will probably end up with a mixed carbonate…

CsHCO₃ + NaOH → CsNaCO₃ + H₂O

Of course, I could turn caesium bicarbonate into caesium chloride, but then would the metathesis work? (Thinking of it, it might, given it works with sodium and potassium).

CsCl + NaOH → CsOH + NaCl.

From CsOH, it’s easy to turn back to Cs₂CO₃ just by bubbling CO₂ in the solution… (I wouldn't want to isolate CsOH, since it apparently attacks glass).

unionised - 17-5-2023 at 11:24

Bicarbonates decompose on heating to form carbonates.

Fery - 18-5-2023 at 05:04

Keras - Cs2CO3 is perhaps the most hygroscopic carbonate. I got it cheap but slightly wet. It dried in a desiccator over silica gel nit earlier than in 2 months. I got it in original chemical bottle. After drying I put the bottle into 2 layers of sealed plastic bags. I did not want to heat it as it would certainly completely dissolve in that traces of moisture. Solubility in water is 2605 g/L (15 °C).

Keras - 19-5-2023 at 12:16

Quote: Originally posted by Fery  
Keras - Cs2CO3 is perhaps the most hygroscopic carbonate. I got it cheap but slightly wet. It dried in a desiccator over silica gel nit earlier than in 2 months. I got it in original chemical bottle. After drying I put the bottle into 2 layers of sealed plastic bags. I did not want to heat it as it would certainly completely dissolve in that traces of moisture. Solubility in water is 2605 g/L (15 °C).


Thanks for that! I’m not sure I really care about its water contents, since I plan to use it with dimethyl carbonate and p-cresol, in a methylation reaction which basically doesn’t care about traces of water.

I’ll tell you when it arrives how it went!