$P$, $\rho$, $T$-properties and phase equilibria in the water-$n$-hexane system with a low content of water

Using a piezometer of constant volume, we determined experimentally the $P$, $\rho$, and $T$ properties and the phase equilibria for the binary water-$n$-hexane mixtures with $0.04$, $0.05$, $0.06$, and $0.0673$ mass fraction of $H_2O$ over the density range of $0.067$–$0.607\text{ g/cm}^3$, temperature range of $380$–$680$ K, at pressures up to $60$ MPa. The equilibrium lines of the liquid-liquid and liquid-gas transition have been determined. The three-phase line, the line of the azeotrope, and the lower branch of the critical line (all lines are joined at the upper finite critical point) have been plotted in the work.