[inicardini]

Hi, I'm a graduate mechancial engineer and my chemistry's a bit rusty, so I need help here. I know that calcium carbonate is converted to calcium bicarbonate in the presence of water saturated with CO2, I'm wondering if the same reaction will occur if calcium bicarbonate is in the presence of steam and CO2. Does anyone know?

Thanks

[AWK]

Calcium bicarbonate undergoes thermal decomposition.

See: temporary hardness
under
http://en.wikipedia.org/wiki/Hard_water

[inicardini]

Sorry, I meant what would be the reaction of Sodium Carbonate (Na2CO3) with Carbon dioxide in the prsence of steam.
Thanks

[technologist]

Yes it is Possible but conversion of CO2 or Carbonate into bicarbonate will be very low due to higher temperature.

[AWK]

NaHCO3 start decomposition as all hydrogen carbonates between 50 to 80 C. (over 100 C the decomposition is very fast - baking soda). Formation of precipitate is a driving force that cause lowering of decomposition temperature. High pressure of CO2 works as always according to the law of mass action.