Heteropoly anion on carbon: characterization and use in 2,3,6-trimethylphenol oxidation

Abstract Heteropoly anion on modified carbon (PMo 9 V 3 O 40 6− ) is an effective catalyst for the oxidation of 2,3,6-trimethylphenol with molecular oxygen in AcOH/H 2 O 95/5 vol%. The selectivity and activity of this catalyst relates to the carbon's surface modification. Heteropoly anions (HPAs) are strongly adsorbed to N-containing carbons. HPA adsorption can occur by coulombic attraction to protonated N-containing functional groups. HPAs retain the Keggin structure upon adsorption according to FTIR data. The solvent and the carbon surface chemistry determine the leaching of HPA, which is almost zero for N-containing carbon-supported HPA in acidic media.