The oxidation of aromatic derivatives in aqueous goethite slurry at varying catalyst load and hydrogen peroxide concentration is investigated. For adopted experimental conditions only the compounds containing two adjacent -OH groups or one -OH and one -NH2 groups are oxidized. A model previously developed for the oxidation of 3,4-dihydroxybenzoic acid has been satisfactorily used to describe the oxidation of 1,2-benzenediol (catechol), 2-aminophenol and 2,3-dihydroxybenzoic acid.