Liquid–Liquid Equilibrium of the System: Water + Ethanol + Heptane + Δ9-Tetrahydrocannabinol and Cannabidiol

In the development of novel medical cannabis products, several technologies have been proposed, including Centrifugal Partition Chromatography. This technique enables the separation of compounds through multiple liquid–liquid extraction processes that occur inside the equipment. The biphasic solvent system used for the isolation of Δ9-tetrahydrocannabinol (Δ9 - THC) from cannabidiol (CBD) enriched matrices consists of n -heptane, ethanol, and water. In this study, experimental data on the liquid–liquid equilibrium (LLE) of a system comprising water, ethanol, n -heptane, Δ9-THC, and CBD at 282.15, 285.15, and 288.15 K at 75.11 kPa are presented. To fit the LLE data, the nonrandom-two-liquid model was applied using an in-house MATLAB application. Binary interaction parameters for the multicomponent system were calculated and are also reported in this study. This research contributes to the generation of new knowledge by (i) providing binary interaction parameters between cannabinoids and the selected solvents and (ii) offering a detailed analysis of liquid–liquid equilibria in cannabinoid separation processes, with valuable implications for future applications in the field. The parameter estimations were shown to be thermodynamically consistent through both graphical and numerical analysis.