Reaction Equilibria in the Synthesis of 2-Methoxy-2-methylbutane and 2-Ethoxy-2-methylbutane in the Liquid Phase

Article abstract of DOI:10.1021/je00016a013

Equilibrium constants for the liquid-phase synthesis of 2-methoxy-2-methylbutane (TAME) and 2-ethoxy-2-methylbutane (TAEE) were measured in the temperature range 323-363 K.The equilibria were studied using the alcohol/alkene mixture in various mole ratios and the respective ether as a reagent in a batch reactor.A commercial cation exchange resin (Amberlyst 16) was used as the catalyst.The system was strongly nonideal, and the UNIQUAC estimation method was used in the calculation of the liquid-phase activity coefficients.The experimental equilibrium constants are given as a function of temperature.At 333 K the equilibrium constants K_a for the synthesis of TAME were 39.6+/-2.5 from methanol and 2-methyl-1-butene (2M1B) and 4.1+/-0.3 from 2-methyl-2-butene (2M2B).The equilibrium constants for the synthesis of TAEE were 17.4+/-1.1 from ethanol and 2M1B and 1.7+/-0.1 from 2M2B.The experimental Δ_rH values for the liquid-phase synthesis of TAME were -33.6+/-5.1 kJ*mol^-1 (2M1B) and -26.8+/-2.3 kJ*mol^-1 (2M2B), and those for the synthesis of TAEE were -35.2+/-5.8 kJ*mol^-1 (2M1B) and -27.3+/-6.7 kJ*mol^-1 (2M2B).The results were compared with the literature values.