Work

Oxidative Catalytic Depolymerization of Lignin into Value-Added Monophenols by Carbon Nanotube-Supported Cu-Based Catalysts

Year: 2024

Type: article

Abstract: Lignin valorisation into chemicals and fuels is of great importance in addressing energy challenges and advancing sustainable biorefining. This study developed a series of copper oxide loaded carbon nanotube (CuO/CNT) to facilitate the oxidative depolymerization of lignin. High catalytic activity was demonstrated by the CuO/CNT-600 catalyst, which had a specific surface area of 189 m2/g and an abundance of CuO-Cu2O specie. By optimizing the reaction parameters, the bio-enzymatic lignin could obtain a higher monophenol yield (13.7%) at 200 oC for 20 min. The application of CuO/CNT catalysts with various types of lignin revealed distinct selectivity for G/H/S-type products. Electron paramagnetic resonance tests were conducted to elucidate the oxidation mechanism. The results indicated that both •OH and O2•− are essential for selectively producing aldehyde and ketone products through the cleavage of lignin Cβ-O and Cα-Cβ bonds. Overall, this study provides an effective oxidation strategy for lignin biorefining practices.

Source: Molecules

DOI: 10.3390/molecules29194762