(Liquid + liquid) equilibria in {water + acrylic acid + (1-butanol, or 2-butanol, or 1-pentanol)} systems at T = 293.2 K, T = 303.2 K, and T = 313.2 K and atmospheric pressure

(Liquid + liquid) equilibrium (LLE) data for {water + acrylic acid + (1-butanol, or 2-butanol, or 1-pentanol)} at T = 293.2 K, T = 303.2 K, and T = 313.2 K and atmospheric pressure (≈95 kPa) were determined by Karl Fischer titration and densimetry. All systems present type I binodal curves. The size of immiscibility region changes little with an increase in temperature, but increases according to the solvent, following the order: 2-butanol < 1-butanol < 1-pentanol. Values of solute distribution and solvent selectivities show that 1-pentanol is a better solvent than 1-butanol or 2-butanol for acrylic acid removal from water solutions. Quality of data was ascertain by Hand and Othmer-Tobias equations, giving R2 > 0.916, mass balance and accordance between tie lines and cloud points. The NRTL model was used to correlate experimental data, by estimating new energy parameters, with root mean square deviations below 0.0053 for all systems.

► Acrylic acid solubilizes preferably in the studied solvents than in water.
► Immiscibility region increases in the order: 2-butanol < 1-butanol < 1-pentanol.
► Immiscibility region reduces little with an increase in temperature.
► K and S values show that 1-pentanol is the best studied solvent.