Oxidation of 2,4,6-trichlorophenol catalyzed by iron(iii)-tetraphenylporphyrin tetrasulfonate with different oxidants

In this study, the oxidation of 2,4,6-trichlorophenol (TCP) catalyzed by iron-tetraphenylporphyrin tetrasulfonate ([FeTSPP]), cobalt-tetraphenylporphyrin tetrasulfonate ([CoTSPP]), nickel-tetraphenylporphyrin tetrasulfonate ([NiTSPP]), paladium-tetraphenylporphyrin tetrasulfonate ([PdTSPP]) and copper-tetraphenylporphyrin tetrasulfonate ([CuTSPP]) has been investigated. TCP was oxidized by oxone (potassium peroxymonosulfate), tert-butylhydroperoxide (ButOOH) and hydrogen peroxide (H2O2). The reactions were carried out in %10-15 of water in methanol solutions by volume at room temperature and the effects of the concentration of substrate, catalyst and oxidant on the outcome of the reactions were investigated. The product compositions of the reaction mixtures were identified using GC-MS and amounts of the products were calculated using GC chromatograms. While [FeTSPP] showed high catalytic activity in the oxidation of TCP, cobalt-, nickel-, palladium- and copper-tetraphenylporphyrin tetrasulfonate did not show any activity. When the catalyst:substrate:oxidant mole ratios were kept in 1:500:300 in the catalysis by [FeTSPP], the highest turnover number (TON) and turnover frequency (TOF) values were obtained. In order to improve recycling number of the catalyst, [FeTSPP] was bound to Amberlite IRA-900 resin and a cationic latex which contains 50% quaternized ammonium group. When the [FeTSPP]-IRA was used, its recycling numbers were increased, but optimum time of reaction was decreased.