Characterizing Wood Liquefaction by Fractal Geometry Approach


  • Qiuhui Zhang
  • Erni Ma
  • Guangjie Zhao
  • Qingqing Li
  • Shuai Mao


Chinese fir (<i>Cunninghamia lanceolata</i> Hook), liquefied wood residues, residue content, surface fractal dimension, wood liquefaction


This study characterized wood liquefaction by the fractal geometry method. Chinese fir (Cunninghamia lanceolata Hook.) fine powderwas liquefied under various conditions of phenol-to-wood ratio (3:1, 4:1, and 5:1), catalyst content (4, 6, and 8%), and temperature (130, 150, and 170°C). The surface fractal dimension of liquefiedwood residueswas determined at different liquefaction time levels (30, 60, 90, 120, 150, and 180min) by software based on the cubic coveringmethod. The relationship between fractal dimension and residue content was examined quantitatively. Results indicated that 1) surface fractal dimensions of liquefied wood residues were between 2.27 and 2.30 under all liquefaction conditions; 2) surface fractal dimension was inversely related to liquefaction time, and it decreased faster at early liquefaction stages; 3) surface fractal dimension was inversely related to phenol-to-wood ratio, catalyst content, and liquefaction temperature; and 4) the relationship between surface fractal dimension and residue content could be described by a linear function with high R2 values. This study provides a new alternative to the arsenal of wood liquefaction characterization methods and also sheds light on some fundamental aspects of wood liquefaction research.


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