Mechanism study of degradative solvent extraction of biomass

Liquid phase pyrolysis of wheat straw and poplar in hexadecane solvent

“…The LPP(DE) experiments performed with 1-methylnaphtalene showed very high conversion. The amount of the residue for the fir sawdust and rice straw were only 3 and 19 wt%, respectively [15,16]. Similar elemental composition was obtained for the residue (biochar) independently of the used solvent and wt% hydrogen and 20.6 wt% oxygen.…”

“…Water assisted liquefaction requires severe conditions, such as, 50-200 bar pressure and 250-350 °C temperature. An alternative route to process lignocellulosic materials is degradation in none-hydrogen donor organic solvent referred to as liquid phase pyrolysis (LPP) [8][9][10][11][12][13] or degradative extraction (DE) [14][15][16]. According to this method lignocellulosic material is treated at ~350 °C under liquid phase organic solvent and inert atmosphere at relatively low pressure (max.…”

“…Gases, mainly CO 2 , and water solubles, non-miscible with the applied solvent, mainly H 2 O, are also formed. Studies report about the use of different organic solvents, such as, mixture of n-alkanes, boiling in the temperature range of 410 and 440 °C [8,9], vacuum gasoline (VGO) that is a mixture of alkanes and aromatics, having a boiling range of 300-580 °C [10,11,13], n-hexane (bp: 69 °C) [12] and 1-methylnaphtalene (bp: 240-243 °C) [14][15][16].…”

“…The used equipment setup has also great effect on the experimental results. Zhu et al [16] reported about extremely low yields of residue (3-5 wt%), i.e., the conversion of fir sawdust, pyrolyzed in 1-methylnaphtalene at 350 °C, was almost complete [16]. The yields of the other products varied between 10-30 wt% for deposit (not soluble in the heat carrier at room temperature), 25-40 wt% for soluble (materials dissolved in heat carrier), 20-30 wt% for liquid (water soluble products) and 12-15 wt% for gases.…”

“…With regard to further processing technology the most important characteristics are the amount of organic material transferred from the biomass to the organic solvent and the chemical composition of the transferred (extracted) material. The amount of bio-carbon transferred to the solvent can be obtained from the mass-balance of the transformation [16] or by measuring 14 C contents using Accelerator Mass Spectrometry (AMS) [8,10,11,17], and Liquid Scintillation Counting (LSC) [17,18]. Qualitative identification of pyrolysis products is a very challenging task.…”