To model the reactive solid phase contribution, knowledge of the solubility and mass transfer should be extracted from empirical measurements. Often unknown factors may complicate the interpretation of the data. In this paper we consider an example of this kind and present a practical procedure that allows one to avoid these difficulties. A simplified model is derived for the mass transfer and kinetics. This model provides the insight that leads to an optimal protocol for estimation of the parameters of interest. (c) 2006 Elsevier Ltd. All rights reserved.