Synthesis of Macroporous Ellagitannic Acid Resin and Its Chelating Properties for Metal Ions

A new type of macroporous ellagitannic acid resin (EAR) can be prepared from macroporous crosslinked chloromethylated polystyrene beads and ellagic acid in the presence of NaOH and KI as catalysts. The synthetic route and structure of the polymer were examined. The structure of EAR was confirmed by elementary analysis and IR spectra. The oxygen content of EAR was 7.06%, and the functional group capacity of EAR was 0.441 mol EA/g EAR. The conversion of functional groups was 8.33%. Cu2+, Fe3+, Ce3+, and La3+ can be easily adsorbed by EAR. The adsorption capacities for these metal ions per g EAR were 0.609 mmol Cu2+, 1.523 mmol Fe3+, 0.320 mmol Ce3+, and 1.561 mmol La3+. The influence of pH, acidity, ionic concentration, adsorption time, and temperature on the percentage of adsorption was investigated.