This study aimed to explore the influence of inherent hierarchical porous char with alkali and alkaline earth metallic species (AAEMs) during pyrolysis of lignin derived from agricultural crop residues in a laboratory fixedbed at 550 degrees C. A catalytic strategy was implemented to investigate volatile-char interactions based on ex situ lignin pyrolysis. The physico-chemical properties of the AAEMs-loaded char were characterized by FTIR, XRD, SEM-EDX and N-2 nitrogen adsorption analyses. Results indicated that AAEMs-loaded char had a large specific surface area, hierarchical porosity, amorphous carbon structure, surface-active functional groups and highly dispersed metal species. Specifically, the specific surface area of AAEMs-loaded char was significantly reduced owing to coke deposition after interaction with pyrolysis vapours. Bio-oil composition revealed substantial increases in phenol, o-cresol, p-cresol and catechol. These increases were mainly attributed to demethylation, demethoxylation, or alkyl substitution reaction. The experimental results confirmed the occurrence of significant volatile-char interactions during lignin pyrolysis.