Densities and Viscosities for Binary Mixtures of the Ionic Liquid N-Ethyl Piperazinium Propionate with n-Alcohols at Several Temperatures

A novel ionic liquid N-ethyl piperazinium propionate, [NEPP], was prepared, and the densities and viscosities for the binary mixtures of [NEPP] with methanol, ethanol, n-propanol, and n-butanol were measured over the whole concentration range at (298.15, 303.15, 308.15, and 313.15) K and 0.1 MPa. The data of the excess molar volume, VmE, were calculated and fitted with the Redlich–Kister type polynomial equation. The values of VmE of the investigated systems are all negative, indicating that the ion–dipole interactions play important roles between the molecules of the ionic liquid and the alcohols.