Experimental data and thermodynamic modeling for n-propane + Brazil nut oil at high pressures

This research aimed to uncover essential phase transition data for the pseudo-binary system of n-propane and Brazil nut oil. Over a range of temperatures from 313 to 343 K and pressures up to 3.42 MPa, our study identified various phase equilibria, including liquid-vapor, liquid-liquid, and liquid-liquid-vapor, using the visual synthetic-static variable volume method. The observed phase transitions fall under the type III classification proposed by Scott van Konynenburg. Leveraging the cubic Peng-Robinson equation of state with the van der Waals mixing rule, we were able to construct isopleths for the proposed system. Additionally, we examined the fatty acid profile of Brazil nut oil to accurately quantify its composition and estimate critical properties of the pseudo component in line with Kay's rule. This research provides critical insights into the behavior of phase diagrams for pressurized fluid-based extraction and separation processes, which are crucial for achieving maximum yield and minimizing energy expenditure.