Diffusion coefficients of iodide in high temperature aqueous solutions

Abstract The diffusion coefficients of iodide in water solutions containing NaHSO4 as supporting electrolyte have been measured between 102 and 215 °C using a high-temperature wall-tube cell. The temperature behavior of the diffusion coefficients is well described by the Arrhenius law and the activation energy for the mass transport is 17 kJ mol−1. The results are compared to those calculated from the iodide conductivity at infinite dilution and to recent results from other authors. The solvation and speciation of the iodide ion in aqueous solutions at high temperature are analyzed.

[1]  J. Sengers,et al.  An Improved Representative Equation for the Dynamic Viscosity of Water Substance , 1980 .

[2]  P. G. Hill.  A UNIFIED FUNDAMENTAL EQUATION FOR THE THERMODYNAMIC PROPERTIES OF H2O , 1990 .

[3]  M. H. Lietzke,et al.  The Equilibria and Kinetics of Iodine Hydrolysis , 1982 .

[4]  Isaac Trachtenberg,et al.  Electrochemistry in near-critical and supercritical fluids. 3. Studies of bromide, iodide, and hydroquinone in aqueous solutions , 1986 .

[5]  L. Cantrel,et al.  Voltammetric Analysis of Iodide and Diffusion Coefficients Between 25 and 85°C , 1998 .

[6]  A. Bard,et al.  Electrochemistry in Near-Critical and Supercritical Fluids. 9. Improved Apparatus for Water Systems (23-385 °C). The Oxidation of Hydroquinone and Iodide , 1997 .

[7]  D. Chin,et al.  Mass Transfer to an Impinging Jet Electrode , 1978 .

[8]  J. Rasaiah,et al.  Solvent Structure, Dynamics, and Ion Mobility in Aqueous Solutions at 25 °C , 1998 .

[9]  M. Spiro,et al.  Tracer diffusion coefficients of I–, I–3, Fe2+ and Fe3+ at low temperatures , 1990 .

[10]  H. Corti,et al.  HIGH-TEMPERATURE WALL-TUBE CELL : DESIGN, CHARACTERIZATION AND RESULTS OF MASS TRANSPORT PHENOMENA , 1997 .

[11]  J. O. Berg,et al.  Application of Stokes' law to ions in aqueous solution , 1990 .

[12]  R. W. Ramette,et al.  Triiodide ion formation equilibrium and activity coefficients in aqueous solution , 1984 .

[13]  D. G. Leaist.  Ternary diffusion with charged-complex formation in aqueous I2+NaI and I2+KI solutions , 1988 .

[14]  W. L. Marshall,et al.  Electrical conductances of some alkali metal halides in aqueous solutions from 0 to 800.deg. and at pressures to 4000 bars , 1969 .

[15]  J. Newman.  Schmidt Number Correction for the Rotating Disk , 1966 .