Recycled carbon (RC) materials made functional: An efficient heterogeneous Mn-RC catalyst
作者:E. Seristatidou、A. Mavrogiorgou、I. Konstantinou、M. Louloudi、Y. Deligiannakis
DOI:10.1016/j.molcata.2015.04.001
日期:2015.7
A Mn-II-Schiff-base catalyst was synthesized and covalently immobilized onto Pyrolytic Carbon surface from waste tyres (PCox), resulting in the heterogeneous catalyst Mn-II-L@PCox which was evaluated for degradation of methyl orange (MO) using NaIO4 as oxidant. Importantly, no additive as co-catalyst was needed. For comparison, a reference heterogeneous catalyst Mn-II-L@AC(ox) was also tested, using Activated Carbon (AC(ox)) as carbon matrix. The catalytic and recyclability data of Mn-II-L@PCox catalyst demonstrate that it is superior, in terms of TONs and TOFs vs. Mn-II-L@AC(ox). To study the reaction path, electron paramagnetic resonance spectroscopy was used to monitor the redox evolution of the Mn-centers. Furthermore, a full mapping of the catalytic degradation of MO and product formation was carried out using LC-MS and HPLC. Combining catalytic and spectroscopic data we discuss the protective effect of the PCox matrix on Mn-centers: it allows their rapid redox evolution to higher oxidation states. (C) 2015 Elsevier B.V. All rights reserved.