Phase behavior of the binary mixture of cyclohexyl acrylate and cyclohexyl methacrylate in supercritical carbon dioxide

Pressure-composition isotherms are obtained for binary mixtures of carbon dioxide + cyclohexyl acrylate and carbon dioxide + cyclohexyl methacrylate systems at (313.2, 333.2, 353.2, 373.2, and 393.2) K and pressures up to 20.6 MPa. The solubility of cyclohexyl acrylate and cyclohexyl methacrylate for the carbon dioxide + cyclohexyl acrylate and carbon dioxide + cyclohexyl methacrylate systems increases as the temperature increases at constant pressure. The carbon dioxide + cyclohexyl acrylate and carbon dioxide + cyclohexyl methacrylate systems exhibit type-I phase behavior, characterized by a continuous critical line from pure carbon dioxide to the second component with a maximum in pressure. The experimental results for the carbon dioxide + cyclohexyl acrylate and carbon dioxide + cyclohexyl methacrylate systems have been modeled using the Peng-Robinson equation of state. A good fit of the data is obtained with the Peng-Robinson equation using two adjustable interaction parameters for each system.