Regulating aromatic hydrocarbon components from catalytic pyrolysis of corn cob lignin with a tailored HZSM-5@Al-SBA-15 hierarchical zeolite

Abstract

Catalytic pyrolysis of corn cob lignin were preformed using a tailored HZSM-5 @Al-SBA-15 hierarchical zeolite for the production of value-added aromatic hydrocarbon. Resulted showed that the highly ordered two-dimensional p6mm mesoporous shell could uniformly form on the surface of HZSM-5 core phase. The porosity and acidity of the HZSM-5 @Al-SBA-15 could be tailored by adjusting the TEOS/HZSM-5 mass ratio in the synthesis process. The aromatic hydrocarbon components regulated due to pre-cracking and enhanced diffusion via the mesoporous shell, as well as the retained shape-selectivity of the HZSM-5 core. Herein, the relative content of MAHs reached 45.02% with fewer poly-aromatic hydrocarbons (PAHs) of 25.91% when the TEOS/HZSM-5 mass ratio of 1.0. However, the length of the diffusion path had a certain impact on the anti-coking behavior. The catalytic stability of the hierarchical zeolites was also improved, with less coke formation than HZSM-5 alone. This work demonstrates that using a tailored hierarchical zeolite to regulate aromatic hydrocarbon components is feasible, and provide a reference for the practical application of agricultural crop wastes.