Ozonation of an Extracted Aquatic Fulvic Acid : Theoretical and Practical Aspects

A laboratory study was conducted on the ozonation of an aquatic fulvic acid extracted from a forest pond near Poitiers in France. The rate of molecular ozone consumption was fast during the first minutes, and ozonation led to a slight increase of the lower apparent molecular 'weight, an enhancement of carboxyl content, and aldehyde formation. By ozonation of a bromide-containing solution of fulvic acid, some brominated organics were formed, while ozonation without bromide led to a reduction of the organic halide formation potential of a fulvic acid, especially in the presence of bicarbonate ions. The increase of GAC-filtration efficiency following ozonation was found to be the result of a biodegradability enhancement of fulvic acid by ozone. Manganese oxidation by ozone was partially inhibited by fulvic acid, particularly in the absence of bicarbonate ions.