Science of Sintering (Jan 2020)
Thermodynamic aspect of sodium carbonate mechanical transformations under different environment
Abstract
During mechanical activation, the energy of treated material is raised to a higher level that can lead to the chemical transformation of the activated material. This is the point that should be considered as a phenomenon of the mechanochemical transformations appearing as a result of mechanical activation. Sodium carbonate as a substance that is often subjected to mechanochemical synthesis was mechanically activated in this study. The subject was the monitoring of changes in the physico-chemical characteristics of sodium carbonate after exposure to different degrees of activation time within the range of 1-28 minutes. After activation, the samples were deposited in three environments, CO2, air, and vacuum, at room temperature, in a period of 64 days. The mass changes occurring during the treatment were measured depending on the processing environment. Increasing the mass was evident and was attributed to the chemisorption of moisture and carbon dioxide present in the air as a consequence of the sodium carbonate activation. The methods also used were calcimetric chemical analysis and X-ray structural analysis. According to obtained results, it was found that activated sodium carbonate is mass-transformed into sodium bicarbonate, whereby these changes are functionally dependent on activation time and the processing environment.
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