Liquid–Liquid\nEquilibrium Measurement and Thermodynamic\nModeling for Ternary Mixtures (Methyl <i>tert</i>-Butyl\nEther + Methanol + Ethylene Glycol/Ethanolamine/Diethanolamine) at\n298.15 K

Methyl <i>tert</i>-butyl ether (MTBE) is a\ncolorless\nand transparent liquid that exhibits excellent miscibility with gasoline.\nIt is employed extensively in gasoline formulations due to its efficacy\nin augmenting the octane number. Additionally, high-purity MTBE can\nbe applied as a pharmaceutical intermediate. For the purification\nof MTBE during its production, it can form an azeotrope with methanol.\nIn this work, to purify MTBE from the azeotrope via extraction, the\nefficacy of three organic solvents ethylene glycol, ethanolamine,\nand diethanolamine as potential extractants was assessed. The liquid–liquid\nequilibrium data of the ternary systems (methanol + MTBE + ethylene\nglycol/ethanolamine/diethanolamine) were ascertained at 298.15 K.\nThe effectiveness of the extracting agents was evaluated with the\ncalculated selectivity and the distribution coefficient. The findings\ndemonstrated that ethanolamine displays a superior extraction capacity\nfor extracting methanol. The ascertained data were correlated by applying\nthe NRTL model, achieving the root-mean-square deviation values that\ndid not exceed 0.01. The reliability of the model’s optimal\nparameters was verified by topological analysis, confirming its coherence\nwith the experimental data.