Binary Analysis on Interaction between Cellulose, Lignin, and Xylose during Hydrothermal Carbonization

Binary mixtures of cellulose, xylose, and lignin were hydrothermally carbonized using an autoclave reactor at 280 °C for 2 h. Mass yield, carbon content of the product hydrochar, and carbon yield were determined by changing the component ratio in the feedstock to elucidate the interaction between components. No Interaction were observed between feedstock components. However, an interaction was observed in the liquid product. Cellulose and xylose produced common liquid products including acetic acid, levulinic acid, and glycolic acid; however, when mixed with lignin, levulinic acid generation was suppressed while glycolic acid generation was enhanced. The equations were derived based on a model without interactions between the components, and their parameters were determined. The resulting equations reproduced the experimental yield and carbon content with an average relative error of 0.102.