Synergistic effect of supercritical water and nano-catalyst on lignin gasification

Understand the microscopic mechanism of supercritical water catalytic gasification is of great significance for more efficient and convenient utilization of biomass energy. In this work, Pt and Ni nano-particles (NPs) were used as catalysts to accelerate the SCWG of guaiac-based lignin dimer with 7-O-4 linkages for the first time, and the SCWG processes at different conditions were simulated by reaction molecular dynamics simulation to understand the degradation mechanism and the path of gas generation. The simulation results indicate that PtNPs and NiNPs apparently reduce the temperature at which the gasification reaction can take place and the by-products of 7-O-4 lignin by increasing the degradation rate into monomer, accelerating the aromatic ring opening, and adsorbing CO, CO2 and CH4. Compared with NiNPs, the synergy of PtNPs and SCWG shows more excellent properties. (c) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

Understanding the microscopic mechanism of supercritical water catalytic gasification is crucial for the efficient utilization of biomass energy. Pt and Ni nano-particles were used as catalysts to accelerate the SCWG of lignin dimer, with PtNPs showing more excellent properties in synergy with SCWG compared to NiNPs. The simulation results revealed that PtNPs and NiNPs reduce the gasification temperature and accelerate the degradation of lignin into monomers by adsorbing CO, CO2, and CH4.