Low Cost Transformation of Dioxins to Nontoxic Forms

点击翻译按钮获取中文摘要

The Low cost transformation of chlorinated compounds such as dioxins to nontoxic forms has been developed utilizing photocatalytic reductive dechlorination of chlorinated compounds by chemical reductants. This process is initiated by photoinduced electron transfer from the singlet excited state of the catalyst to chlorinated compounds, which is followed by the reduction of the oxidized catalyst by the chemical reductants. An NAD^+ analogue (10-methylacridinium ion) has been employed as an efficient photocatalyt for the reductive dechlorination of chlorinated compounds. The redox properties of NAD^+ analogues have been determined by examining the electron transfer reduction and the detection of the radical intermediates. The redox properties of the reduced forms, i.e., NADH analogues have also been determined by examining the electron transfer oxidation.The efficient and selective oxygenation of p-xylene to p-tolualdehyde is also initiated by photoinduced electron transfer from p-xylene to the singlet excited state of 10-methyl-9-phenylacridinium ion under visible light irradiation, followed by the deprotonation of p-xylene radical cation and the facile addition of oxygen to the deprotonated radical, leading to yield p-tolualdehyde exclusively as the final oxygenated product. The factors to improve the photocatalytic reactivity of the photocatalyst have been clarified.