Mössbauer spectroscopic study of the decomposition mechanism of ankerite in CO2 atmosphere

Mrssbauer spectroscopy has been used to identify the iron-containing products that are formed during the thermal decomposition of ankerite in a CO 2 atmosphere. The decomposition takes place in three stages and evidence is produced to show that the first stage involves decomposition of ankerite to yield a periclase-wustite solid solution, (Mg,Fe)O, along with calcite and CO2, the periclase-wustite then reacting with CO 2 to produce magnesioferrite (MgFe204) and CO. In the second stage the magnesioferrite and calcite react to produce periclase and dicalcium ferrite. The third stage does not involve reaction of Fe-containing phases and corresponds to the decomposition of calcite to CaO. KEYWOR9S: ankerite, decomposition, Mrssbauer spectroscopy, CO 2 atmosphere.