Lignin is mainly composed of hydroxy-substituted or methoxylated phenyl propane structures and serves as the only renewable bulk feedstock in nature for producing aromatic chemicals. By using suitable catalysts, the long chain structures of lignin can be selectively broken down to obtain different target products. This has been regarded as an important approach for the comprehensive utilization of lignin. Due to the high activity of hydrodeoxygenation, transition metal sulfide catalysts have been used in lignin conversion in recent decades. In this review, the application of transition metal sulfide catalysts in the catalytic conversions of lignin and its model compounds are summarized. The active components, support materials, reaction conditions and reaction mechanism are presented in detail. The existing challenges of sulfide catalysts in the degradation of lignin are discussed. Finally, potential solutions and future trends of this field are presented.
Contents
1 Introduction
2 The application of sulfide catalysts in the hydrodeoxygenation of lignin model compounds
2.1 Mo-based sulfide catalyst
2.2 Other sulfide catalysts
3 The application of sulfide catalysts in the degradation of lignin raw materials
4 Conclusion