A novel approach for lignin modification and degradation

We report on a novel approach, the integration of the photochemical and electrochemical oxidation, for the modification and degradation of kraft lignin, where the Ta2O5-IrO2 thin film was used as the electrocatalyst and the TiO2 nanotube arrays were used as the photocatalyst. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to characterize the fabricated catalysts. A UV-Vis spectroscopy was used to monitor the processes of the photochemical and/or electrochemical degradation of lignin. The modified lignin was characterized using Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy, while the intermediates produced during the photoelectrochemical process were analyzed by high-performance liquid chromatography (HPLC). Our study has demonstrated that the innovative approach described in this communication provides a promising and energy efficient, environmentally friendly method for lignin modification and degradation. (C) 2010 Elsevier B.V. All rights reserved.