The Behaviour of Sodium Carbonate during Isothermal Heating

JSGT 1933 V17 T009-T021

Charges of sodium carbonate. both alone and mixed with powdered cullet have been heated for varying lengths of time in platinum and in porcelain crucibles. The loss in weight sustained was influenced by the depth of the charge, the temperature, and the time of heating. In platinum the loss did not exceed 1·57% at 1000° in 3 hours, or reach 1% in 1 hour; whilst at 800° the loss was of the order of 0·2%. In porcelain the rate of loss was far heavier, owing to reaction with the walls of the crucible. The presence of cullet scarcely affected the extent of the reaction at 800° but at 1000°, both in platinum and in porcelain, the loss in weight (CO₂) was nearly equal to the calculated. Experiments by a dynamic method confirmed that the loss in weight was due to liberation of CO₂.

M. A. Besborodov.