Kinetic rate equation, Jander

Furusaki et al. [49] reported that the kinetic characteristics of the conversion of LaCr04 (monazite structure) to LaCrOj (perovskite structure) depended onp 0- and that the rate decreased with increasing availability of oxygen. In N2, the reaction (908 to 938 K) fitted the contracting volume expression with , = 198 kJ mol. The rate limiting step for reaction in Oj is the diffusion of oxygen across the product layer, the Jander rate equation applies with about 506 kJ mol. ... 

Although we have shown several kinetic models for reacting solids, none specifically applies to a reaction between two solids. A rate law that was developed many years ago to model reacting powders is known as the Jander equation, and it is written as... 

The solids were suspended in dodecane, and the mixture was sonicated using a pulsed source. At specific times, samples of the soHds were separated from the reaction mixture and analyzed to determine the amount of CdS formed. The extent of reaction was found to vary with sonication time, although the data showed considerable scatter. Although the results did not represent a highly sophisticated kinetic study, they indicated that the Jander equation represents a rate law that should be considered when a model for a reaction between two soHds is being sought. 

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