Novel mild synthesis of high-added-value p-hydroxyphenyl acetic acid and 3,4-dihydroxyphenyl acetic acid using the acidic clay/hydrogen peroxide catalytic system

Abstract

Acid-activated clays KSF and KSF/0 were successfully used in the hydrogen peroxide conversion of phenyl acetic acid to high-added phenolic compounds: p-hydroxyphenyl acetic acid and 3,4-dihydroxyphenyl acetic acid, endowed with a powerful antioxidant capacity. The catalytic conversion enhancement could be correlated to the total surface acidity and the high iron content of the catalysts KSF/0 and KSF, respectively. The synthetic route described here was conducted under mild conditions with very low degree of mineralization and without significant Fe ion leaching observations. The synthesis reaction is operationally simple and could find application for industrial purposes.

Fatty Acid Esterification with Polyols over Acidic Montmorillonite

“…Consequently, the catalytic activity of these K-catalysts is controlled by their acidity. The other physical properties of clays, including surface area and the average pore diameter, do not appear to have a significant effect on the variation of the yield of the reaction 27 . This result is in good agreement with the report of Pushpaletha et al on the correlation between surface properties and catalytic activity of montmorillonite catalysts 28 .…”