Hydrogenolysis of lignin to produce aromatic monomers over Fe-Pd bimetallic catalyst supported on HZSM-5

Highly dispersed Fe-Pd bimetallic catalyst supported on HZSM-5 (Fe-Pd/HZSM-5) was prepared by impregnation method for the hydrogenolysis of lignin. The correlation between the textural properties of the catalyst and its catalytic activity to lignin hydrogenolysis were investigated. The presence of Fe facilitates the dispersion of Pd, and the particle size decreases from 6.1 nm for 3.0 wt% Pd/HZSM-5 (Pd-3.0) to 2.5 nm for 9.0 wt% Fe-1.0 wt% Pd/HZSM-5 (FP-1.0). Fe is mainly existed in the oxidized state which means that electrons in Pd tend to transfer to FeOx, facilitating the activation of H-2 to form active H atoms. Due to the geometric and electronic synergistic effects, FP-1.0 bimetallic catalyst exhibits a good catalytic activity to lignin hydrogenolysis, contributing to as higher as 98.17% of lignin conversion and 27.92% of aromatic monomers yield under the optimal reaction conditions of 1 MPa H-2 at 320 degrees C for 120 min in ethanol-water solvent. FP-1.0 bimetallic catalyst with low cost and highly catalytic activity may be a potentially useful catalyst for selective hydrogenolysis of lignin.

Automated summary

Highly dispersed Fe-Pd bimetallic catalyst supported on HZSM-5 showed good catalytic activity for lignin hydrogenolysis, with FP-1.0 bimetallic catalyst achieving high lignin conversion and aromatic monomers yield. The presence of Fe facilitated Pd dispersion and electron transfer, leading to enhanced hydrogen activation and catalytic performance. FP-1.0 bimetallic catalyst may serve as a cost-effective and highly active catalyst for selective lignin hydrogenolysis.