4-TERT-BUTYLCALIX[6]ARENE (78092-53-2) 's Synthetic route

Efficiency of sulfonic cation-exchange resins used in para-tert-butylphenol production: A comparison based on the kinetics of transalkylation in the phenol-tert-butylphenols system

Voronin  Nesterova  Strelchik  Zhuravskii

The kinetics of transalkylation in the phenol-tert-butylphenols system in the presence of Amberlyst 36 Dry sulfonic cation-exchange resin has been investigated at 353-403 K in the tert-Bu/Ar = 0.10-0.55 mol/mol range. Kinetic characteristics of the o-tert-butylphenol + phenol ai p-tert-butylphenol + phenol (I) and 2,4-di-tert-butylphenol + phenol ai 2p-tert-butylphenol (II) reactions have been determined. The chemical equilibrium in the presence of Amberlyst 36 Dry is reached much sooner than in the presence of KU-23 10/60, a cation-exchange resin used at present. On passing from Amberlyst 36 Dry to KU-23 10/60, the preexponential factor for reaction (I) increases by a factor of 10 and that for reaction (II) increases by a factor of 2000. Thermodynamic characteristics of reaction (I) between 353 and 523 K have been calculated from experimental data and data available from the literature. The thermodynamic characteristics of reaction (II) have been determined experimentally. The enthalpy and entropy of reaction (I) are equal to those of reaction (II). The difference between the equilibrium constants of these reactions is explained. It is recommended that Amberlyst 36 Dry, which proved more efficient than KU-23 10/60, be used in the industrial production of p-tert-butylphenol.