Thermal conductivity and thermal diffusivity of xylene isomers in the temperature range 308–360 K at pressures up to 0.38 GPa

New, absolute measurements of the thermal conductivity of the three xylene isomers within the temperature range 308–360 K for pressures up to 0.38 GPa are reported. In addition, for two of the isomers, m-xylene and p-xylene, it has been possible to measure the thermal diffusivity simultaneously within the same range of conditions. The accuracy of the thermal conductivity data reported is one of ±0.3%, whereas for the thermal diffusivity the estimated accuracy is ±6%. It is found that the density dependence of the thermal conductivity for all of the xylenes can be well represented by one equation based on a rigid-sphere model in the same way that has proved successful for normal alkanes. The thermal diffusivity data have been employed to derive heat capacities for the xylenes over a range of pressures.