Examination of how variations in lignin properties from Kraft and organosolv extraction influence the physicochemical characteristics of hydrothermal carbon

Abstract Seven different lignin samples, three from Kraft extraction and four organosolv extraction, were subjected to hydrothermal treatment at 260℃ for hours assess the impact of type on physicochemical properties material. The 13C Solid state NMR, XPS, FTIR SEM analysis revealed that sources conditions created variations in degree syringyl guaiacyl subunits, inter-unit bonding arrangements, morphology surface composition. Hydrothermal carbonization appeared “normalize” differences between each via breaking β-O-4 or α-O-4 linkages, removal methoxy creation C 4-O-5 linkages polymerization into large 100−200 μm amorphous carbon particles. Overall, this study indicates source have minimal influence structure final product.