A Funnel-Structured 12 × 10-Ring Zeolite Customized for Biomass Catalytic Pyrolysis

Area of Science:

• Materials Science
• Catalysis
• Chemical Engineering

Background:

• Custom zeolite synthesis is crucial for targeted reactions like biomass catalytic fast pyrolysis (CFP).
• CFP requires zeolites with a gradient of large and medium pores to efficiently produce hydrocarbon fuels from biomass.
• Synthesizing zeolites with specific, predefined pore structures remains a significant challenge.

Purpose of the Study:

• To develop a novel heterozeolite with a core-shell structure for biomass CFP.
• To tailor zeolite porosity for enhanced selectivity towards hydrocarbon fuels.
• To demonstrate an in situ partial interzeolite transformation strategy for zeolite engineering.

Main Methods:

• Fabrication of a core-shell HS-ZSM-5@Beta heterozeolite using an in situ partial interzeolite transformation.
• Characterization of the heterozeolite's structure, including the core-to-shell interface and pore architecture, using atomic-level iDPC-STEM.
• Evaluation of the synthesized zeolite's performance in maize straw CFP.

Main Results:

• The HS-ZSM-5@Beta heterozeolite exhibits a seamless core-to-shell interface and funnel-structured 12 × 10-membered ring channels.
• Biomass CFP using HS-ZSM-5@Beta achieved a hydrocarbon selectivity of 57.4 area %, doubling that of conventional ZSM-5.
• The catalyst demonstrated robust activity over eight pyrolysis-regeneration cycles, indicating stability.

Conclusions:

• The in situ partial interzeolite transformation is an effective strategy for fabricating tailored core-shell zeolites.
• The HS-ZSM-5@Beta heterozeolite's unique structure enhances porosity synergy for efficient biomass conversion.
• This study provides a pathway for the rational design of zeolites for specific catalytic applications like CFP.