High-pressure multiphase behavior of the ternary systems (ethene + water + 1-propanol) and (ethene + water + 2-propanol): Part I: Experimental investigation

New experimental results for the high-pressure liquid–liquid–vapor equilibrium and critical endpoints lines of the ternary systems (ethene+water+1-propanol) and (ethene+water+2-propanol) at 293, 313, and 333 K are reported. The entire pressure range was investigated where an aqueous solution of 1-propanol (or 2-propanol) reveals a liquid–liquid phase split when it is pressurized with ethene: that pressure range extends from about 4.5 to about 20.1 MPa (for ethene+water+1-propanol) and from about 7.5 to about 16.6 MPa (for ethene+water+2-propanol), respectively. Furthermore, the temperature–pressure coordinates of both critical endpoint lines ((L1 = L2)V and L1(L2 = V)) were determined and the coordinates of the tricritical point (L1 = L2 = V) were estimated for both ternary systems. Additionally, the formation of hydrates was observed during experiments at lower temperatures (288 and 283 K).