Application of low-cost Fe-based catalysts in the microwave-assisted pyrolysis of macroalgae and lignocellulosic biomass for the upgradation of bio-oil

The combined application of microwave energy and special catalysts holds the potential for the selective conversion of biomass during the pyrolysis process. In this work, steel slag (SS) and biochar-based Fe (RHC/Fe) were adopted as both low-cost Fe-based catalysts and microwave absorbers in the microwave-heating pyrolysis system for the upgradation of bio-oil from macroalgae (Sargassum) and lignocellulosic biomass (pine sawdust). The catalysts all showed strong microwave adsorption performance, exhibiting higher heating rates than that of SiC. SS with a high content of iron oxides plays a catalytic role in biomass decomposition, while RHC/Fe with a highly porous structure not only promotes biomass decomposition but also enhances the secondary reaction of volatiles. The presence of SS significantly improved the content of lighter compounds (

Automated summary

Steel slag and biochar-based Fe catalysts, used as both microwave absorbers and low-cost Fe-based catalysts, show strong microwave adsorption performance in the pyrolysis system, leading to enhanced biomass decomposition and secondary reactions.