Measurements of thermal conductivity of aqueous LiCl and LiBr solutions from 293 to 473 K at pressures up to 100 MPa

High‐pressure thermal conductivities of H2O+LiCl and H2O + LiBr have been measured with a parallel‐plate apparatus. Data cover the pressure range from 0.1 to 100 MPa at temperatures from 293 to 473 K. The concentrations studied were 0.025, 0.05, 0.10. 0.15, 0.20, and 0.25 mass fraction of salts. The estimated accuracy of the method is about ± 1.6%. The pressure, temperature, and concentration dependence of the thermal conductivity has been studied. Measurements were made on six isobars, namely: 0.1, 20, 40, 60, 80, 100 MPa. The thermal conductivity shows a linear dependence on pressure and concentration at all isotherms. Along each isobar a given concentration shows the thermal‐conductivity maximum at temperatures about 413 K. The measured values of thermal conductivity are compared with the results of other investigators.