Diffusion of calcium gluconate in aqueous solutions of lactose at 298.15 K

Binary mutual diffusion coefficients (interdiffusion coefficients) of calcium gluconate (C12H22CaO14) in water at 298.15 K and at concentrations between 0.001 and 0.0500 mol dm(-3) have been measured, using a Taylor dispersion method. These data are discussed on the basis of the Onsager-Fuoss model. Based on these data, the equivalent conductance at infinitesimal concentration of the gluconate ion in the studied solutions has been estimated. Through the same technique, ternary mutual diffusion coefficients (D-11, D-22, D-12 and D-21) for aqueous solutions containing calcium gluconate and lactose, at T = 298.15 K, and at different carrier concentrations, were also measured. These data permit us to have a better understanding of the structure of these systems and the thermodynamic behaviour of calcium gluconate in different media. (C) 2010 Elsevier Ltd. All rights reserved.