Synthesis of polymer-supported copper complexes and their evaluation in catalytic phenol oxidation

Polymer-supported metal complexes have been used as catalysts for the catalytic wet hydrogen peroxide oxidation (CWPO) of phenol. The synthesis of six catalysts derived from three polymer-supports (a polybenzimidazole resin and two poly(styrene-divinylbenzene) resins) and two Cu(II) salts. The catalytic oxidation of phenol with initial phenol concentration of 1 g L−1 was performed in a 200 mL batch stirred tank reactor at 30 °C and atmospheric pressure. Under these conditions, phenol conversion and total organic carbon conversion were evaluated. The highest phenol conversion was 93% obtained for poly(DVB-co-VBC) functionalised with iminodiacetic acid (IMDA) and loaded with copper acetylacetonate, however metal leaching was very unsatisfactory. If metal leaching was taken into consideration, it was found that polybenzimidazole loaded with copper sulphate appeared to be the most stable yielding 54% of mineralisation and 0.75 TOC/phenol conversion efficiency with simultaneously low release of metal during the oxidation.