Excess molar enthalpies (H-m(E)) for mixtures of supercritical CO2 and linalool were measured at conditions of temperature and pressure typical of supercritical extraction processes: 313.15 and 323.15 K and 7.64, 10.00 and 12.00 MPa. The measurements were carried out using an isothermal high-pressure flow calorimeter. The effects of pressure and temperature on the excess molar enthalpy are large. Mixtures formed by low-density carbon dioxide and linalool show very exothermic mixing and excess molar enthalpies exhibit a minimum in the CO2-rich region. The lowest H-m(E) values (approximate to-4000 J mol(-1)) are observed for mixtures at 313.15 K and 7.64 MPa. Mixtures formed by high-density carbon dioxide and linalool show considerably endothermic mixing (approximate to 400-600 J mol(-1)) in the linalool-rich region and moderately exothermic mixing for the other compositions. On the other hand, H-m(E) at 7.64 MPa and 313.15 and 323.15 K varies linearly with CO2 mole fraction in the two-phase region where a gaseous mixture and a liquid mixture of fixed composition, for a given condition of temperature and pressure, are in equilibrium. Results are analyzed in terms of phase equilibria, pure carbon dioxide density and CO2-terpene molecular interactions. Excess molar enthalpies are simultaneously correlated using the Soave-Redlich-Kwong and Peng-Robinson equations of state and the classical mixing rule. The significance of these large variations of H-m(E) with temperature and pressure in the design of supercritical fluid deterpenation processes is discussed. (C) 2007 Elsevier B.V. All rights reserved.