Calcination pore structure variations

It is shown that the mechanism of gas-solid noncatalytic reactions can be understood better by following the variations in pore structure of the solid during the reaction. By the investigation of the pore structures of the limestone particles at different extents of calcination, it has been shown that the mechanism of this particular system can be successfully represented by a two stage zone reaction model below 1000 °C. It has also been observed that the mechanism changes from zone reaction to unreacted core model at higher temperatures. 

Calcination of limestone has been chosen as a model reaction and pore size distributions of the limestone particles are determined at different extents of calcination at different temperatures. Although the calcination reactions have been investigated for ages there are still questions about the actual mechanism of such reactions. The literature does not involve the structural variations. 

In this work it is shown from the variations of pore structure that a zone reaction model similar to the one suggested by Ishida and Wen (9) can explain the mechanism of calcination reaction studied. 

Variations in Pore Structure During Calcination. Typical cumulative pore volume distribution data obtained for different... 

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