Equilibrium constant for ethyl tert-butyl ether vapor-phase synthesis

Article abstract of DOI:10.1021/je00055a001

Equilibrium constants for the vapor-phase synthesis of ethyl tert-butyl ether (ETBE) were determined experimentally at temperatures from 319 to 373 K. Equilibrium was established in the addition of ethanol to isobutene for obtaining ETBE over Amberlyst-15 in a flow reactor maintained at atmospheric pressure. The equilibrium constants obtained in the present work were compared with estimates from thermochemical data. The values of ?H°, ?G°, ?S° at 298 K were obtained from the variation of equilibrium constant with temperature: ?H° = -14.87 ± 0.5 cal·mol^-1, ?GΔR = -2.8 ± 0.8 kcal·mol^-1, and ?S° =-40.5 ± 1.3 cal·mol^-1·K^-1. By use of published thermochemical data together with the experimental data, the enthalpy of formation, ?H_f°₂₉₈, free energy of formation ?G_f°₂₉₈, and absolute entropy, S°₂₉₈, of ETBE were calculated to be -75.03 POM 0.5 kcal·mol^-1, -29.14 ± 0.5 kcal·mol^-1, and 97.1 ± 1 cal·mol^-1·K^-1, respectively.