In this paper, measured quaternary and ternary liquid−liquid equilibrium (LLE) data for 2-methoxy-2-methylpropane (methyl tert-butyl ether, MTBE) + furfural + acetic acid (HAc) + water are presented. The measured data are presented together with the optimized binary interaction parameters for the utilized UNIQUAC-HOC (Hayden− O'Connell) activity coefficient model. Suitability of MTBE for liquid−liquid extraction of furfural in an industrial use is discussed.

Measured quaternary and ternary liquid–liquid equilibrium for 2-methoxy-2-methylbutane (tert-amyl methyl ether, TAME) with furfural, acetic acid, and water are presented in the temperature range between 298 and 341 K. In addition, binary pairs for TAME + water and furfural + water were measured in the range between 298 and 341 K. Results were modeled with UNIQUAC-HOC (Hayden–O’Connell) activity coefficient model and corresponding binary interaction parameters are presented along with measurement data. Solvent suitability for industrial use was assessed for 2-methoxy-2-methylbutane and compared to 2-methoxy-2-methylpropane and other industrial solvents.