CHARACTERIZATION OF SOLID RESIDUES FROM HYDROTHERMAL LIQUEFACTION OF CYPRESS

Effects of temperature on the characters of solid residues obtained from hydrothermal liquefaction of cypress were investigated to understand the mechanism of hydrothermal liquefaction process. The solid residues were divided into acid-soluble solid and acid-insoluble solid residues, and the acid-insoluble solid residues were further divided into carbon, oxygen, and hydrogen. Results showed the polymerization reaction also mainly present at low temperatures. The degradation of cellulose process consists of two steps: an initial hydrolysis of the more solvent accessible amorphous region and a latter hydrolytic attack of the crystalline portion. Hemicelluloses were decomposed to small compounds at the initial stage, and then these compounds may rearrange through polymerization to form acid-insoluble solid residue after 240 degrees C. The higher heating value of the solid residues obtained from liquefaction at 260-300 degrees C was 23.4-26.3 MJ/Kg, indicating that they were suited for combustion as a solid fuel.