Tsodikov M., Ellert O G., Arapova O., Nikolaev S., Chistyakov A., Maksimov Y., 2018, Benefit of Fe-containing Catalytic Systems for Dry Reforming of Lignin to Syngas under Microwave Radiation, Chemical Engineering Transactions, 65, 367-372.
Fe-containing nanoparticles provide for high-rate microwave-assisted dehydrogenation and dry reforming of lignin into syngas without additional carbon sorbent. Lignin samples were obtained by deposition of iron from the acetylacetonate complex and contained 0.05; 0.10; 0.50; 1.50; and 2.0 wt.% Fe, respectively. According to another procedure, iron particles were deposited from a colloid solution of metal particles in toluene prepared by metal vapor synthesis. The obtained sample contained 2.8 wt.% Fe. Study of the microwave-assisted heating dynamics for a number of solid lignin samples with different Fe concentrations revealed the threshold concentration, 0.5 wt % Fe, which ensures the highest heating rate up to the temperature of reforming and plasma ignition. Increasing of Fe content up to 2% led to an increasing selectivity towards syngas production. The process of reforming proposed in this work provides a 90-94 % recovery of hydrogen from lignin. These results suggest that the conversion of lignin follows two pathways giving hydrogen and syngas accompanied by compaction of fused polyaromatic structures to graphitized carbon, which is formed in 35-40% yield.
