oxidation of phenol by hydrogen peroxide catalyzed by metal-containing poly(amidoxime) grafted starch

Polyamidoxime chelating resin was obtained from polyacrylonitrile (PAN) grafted starch. The nitrile groups of the starch-grafted polyacrylonitrile (St-g-PAN) were converted into amidoximes by reaction with hydroxylamine under basic conditions. The synthesized graft copolymer and polyamidoxime were characterized by FTIR, TGA and elemental microanalysis. Metal chelation of the polyamidoxime resin with iron, copper and zinc has been studied. The produced metal-polyamidoxime polymer complexes were used as catalysts for the oxidation of phenol using H2O2 as oxidizing agent. The oxidation of phenol depends on the central metal ion present in the polyamidoxime complex. Reuse of M-polyamidoxime catalyst/H2O2 system showed a slight decrease in catalytic activities for all M-polyamidoxime catalysts.