Estimation of mass transfer parameters during dehydroxylation in a large ceramic body by inverse methods

An inverse problem of the parameter estimation for the water transport during dehydroxylation in a large cylindrical ceramic body is solved. The transport is described by a standard type of non-stationary diffusion equation with a volumetric generation. The inverse problem is solved by the Levenberg–Marquardt method, with the estimated parameters being the water transfer diffusivity and water generation per unit volume. Their temperature dependencies are obtained within the dehydroxylation regime for 450 °C, 500 °C, 550 °C, and 600 °C, using experimental data from isothermal heating measurements. The activation energy of the diffusion process is estimated from the temperature dependence of the diffusivity, yielding 72.9 kJ mol−1.