Novel Hierarchical Disordered Li- and Al-KIL-2 Catalysts for the Pyrolysis of Biomass Model Compounds and Wool Waste: A Comparison with ZSM-5

Abstract

In this study, we investigated the pyrolysis of cellulose, lignin, phenylalanine and textile wool waste using microscale thermogravimetric analysis (TGA) and a gram-scale fixed bed reactor. The pyrolysis was conducted at 500 °C and 1 bar N2, using Al- and Li-doped mesoporous KIL-2 and ZSM-5 catalysts for comparison. Our results show that amorphous Al-KIL-2 catalyst was the most efficient in producing aromatics from cellulose and lignin. This efficiency is attributed to Al-KIL-2 large mesoporosity, wide pore size distribution, and mild acid sites. Additionally, Al-KIL-2 promoted esterification and denitrogenation reactions, indicating its potential application in the pyrolysis of biomass and protein-rich feedstocks. Conversely, the Li-KIL-2 catalyst demonstrated activity primarily in the depolymerisation of cellulose to sugars and promoted ketonisation and alcohol formation. In summary, our findings indicate that Al-KIL-2 is a promising catalyst for efficient aromatic production from biomass.

Keywords

• thermochemical conversion
• catalytic pyrolysis
• lignocellulose
• KIL-2
• wool waste
• aromatics