Glucose‐Assisted Synthesis of Hierarchical HZSM‐5 for Catalytic Fast Pyrolysis of Cellulose to Aromatics

Hierarchical ZSM‐5 zeolites have been successfully synthesized via an introduction of pre‐formed ZSM‐5 precursors and glucose‐assisted method. The influence of the amounts of glucose on the zeolite's characteristics of crystallinity, morphology, pore, and acidity of the HZSM‐5 zeolites were studied detailedly. The synthesized material showed a high mesoporous surface area (164.4–182.7 m2/g) and volume (0.14–0.15 m3/g), while the total acidity amount decreased slightly and Brønsted acidity amount increased. Amongst hierarchical ZSM‐5 zeolites samples, the highest aromatic yield of 43.3 % was obtained, more than the yields of the traditional ZSM‐5 (36.3 %). The increase of mesoporousity is the main reason for the increasing of aromatics yield and reducing of the amount of coke. Hierarchical ZSM‐5 zeolites were prepared by adding glucose. The obviously increase of surface area and mesopore volume of ZSM‐5 zeolites have significantly improved aromatic yields and reduced amount of coke in catalytic fast pyrolysis of cellulose. A series of ZSM‐5 zeolites with hierarchical porosity were prepared by adding glucose into the medial synthesis system. The proper increase of mesoporosity is favor to the reducing of the amount of coke. The highest yield of aromatic was obtained for the mesoporous sample with the greatest microporosity, thus the right balance between meso‐ and microporosity is critical to achieve high aromatic yields.