Advances in the application of molecular sieves as catalysts for lignin depolymerization—HZSM‐5 as an example

Abstract At present, mankind faces the problem of increasingly serious global environmental crisis and growing shortage of petrochemical resources, making it more and more necessary to seek renewable substitute for petroleum. Biomass resources, which have received widespread attention and worldwide research, are the most common source of renewable carbon. Moreover, they are considered to be the major source of renewable green carbon today. Biomass resources contain three main aggregates, which are cellulose, hemicellulose, and lignin, as well as small amounts of other additional materials. Notably, the aromatic ring ethers linkage inside lignin molecules enables it to serve as a renewable and suitable feedstock for the production of aromatic chemicals and fuels. However, the recognition that lignin is the most difficult lignocellulosic biomass to degrade makes it much less valuable for practical applications. Therefore, in order to achieve high‐value conversion and utilization of lignin and replace non‐renewable fossil resources, the targeted conversion of lignin into chemicals and materials has become one of the major hot research areas. To this end, this article reviews research results on the use of molecular sieves (HZSM‐5) as catalysts for lignin degradation and conversion, providing an outlook on future research directions.