THERMAL-CONDUCTIVITY OF AQUEOUS SALT-SOLUTIONS AT HIGH-TEMPERATURES AND HIGH-CONCENTRATIONS

The thermal conductivity-temperature behavior of aqueous salt solutions is examined with particular emphasis on the high-concentration and high-temperature region. We have recently measured the thermal conductivity of LiBr-water solutions at temperatures up to 473 K and concentrations up to 65 wt % LiBr and found that the thermal conductivity surface for aqueous electrolytes is different from the surface obtained by previous investigators. Previous investigators have shown that the thermal conductivity-temperature curves at constant composition are parallel to those for pure water. Our work, on the other hand, indicates that the curves cannot be parallel over the entire composition range. Justification for this behavior is presented, and a new correlation incorporating the correct temperature dependence is proposed.