Determination and correlation of heat of mixing of the carbon dioxide + tert-butyl methyl ether system at 298.15 and 303.15 K and 5.0–7.0 MPa

Abstract

The heat of mixing (ΔHM) of the carbon dioxide + tert-butyl methyl ether system was measured near the critical point of carbon dioxide using a flow-type isothermal microcalorimeter at 298.15 and 303.15 K and 5.0–7.0 MPa. The mixtures showed strong exothermic behavior in these regions. The maximum absolute value of ΔHM (maximum exothermic value) was about 7.9 kJ mol−1 at 298.15 K and 5.0 MPa. A two-phase region, where ΔHM varied linearly with composition, was found in the CO2 rich region at all temperatures and pressures except at 298.15 K and 7.0 MPa.