The oxidation of aqueous solutions of Fe(II)NTA was investigated in a bubble column reactor. The rate of the oxidation reaction was found to be proportional to the partial pressure of oxygen and to have an order of 0.5 with respect to the Fe(II)NTA concentration. The overall transfer of oxygen appears to be predominantly reaction controlled for Fe(II)NTA concentrations in the order of 1 mmol l(-1), whereas for high concentrations (100 mmol l(-1)) mass transfer becomes the controlling factor. Overall mass transfer coefficients and reaction rate constants were determined in the range between 25 and 60 degrees C and for a wide range of Fe(II)NTA concentrations (5-250 mmol l(-1)).