Growth kinetics of the {10.4} faces of (NaNO3)

Abstract

In this paper, we focus on the measurement of the normal growth rates (R104) of {10.4} faces of nitratine (NaNO3) single crystals under isothermal conditions in the temperature interval 288-297.5 K in order to unravel the rate determining steps during crystal growth, depending on the hydrodynamic conditions. Owing to the elevated solubility of nitratine in water, the supersaturated system is very sensitive to temperature variation. In this sense, we have constructed a device to control the temperature (its accuracy is below 0.1 K) and the concentration throughout the experiments. We managed to measure the crystal growth of three symmetry equivalent {10.4} faces of NaNO3 under different hydrodynamic conditions. We found that growth of these faces depends on different rate determining steps (being either surface or volume diffusion limited) according to their position with respect to the solution flow. Finally, some thermodynamic crystallization parameters have been calculated to assess the rate determining steps.