Nineties of the hydroxymethylation of phenol II: values of rate parametersand results of simulation experiments

The reaction course of the sodium hydroxide-catalyzed hydroxymethylation of phenol was analyzed by use of high-performance liquid chromatography (HPLC ), and the rate constants for the seven reactions taking place consecutivel y and competitively were evaluated by means of a computer simulation techni que. Calibration was done at the quantification of the six phenolic monomer s from the peak areas in the HPLC chromatogram, taking the differences in m olar ultraviolet absorption intensities of the six compounds into account. The values of the energies of activation for the seven reactions obtained d iffered greatly from those reported by Eapen and Yeddanapalli. Simulation e xperiments carried out by use of the newly obtained rate parameters showed that the amounts of phenol left unreacted and 2,4,6-trihydroxymethylphenol in the final reaction product increased as the reaction temperature was inc reased and the alkali/phenol molar ratio decreased. These phenomena can be attributed to the differences in the energies of activation for the seven r eactions and differences in the acid strengths of the six phenolic monomers .