Department of Chemical Engineering, Norwegian University of Science and Technology (NTNU), Trondheim, Norway.
Innlandet Fylkeskommune, Hamar, Norway.
Biopolymers. 2022 Sep;113(9):e23520. doi: 10.1002/bip.23520. Epub 2022 Jun 25.
The redeposition of lignin to the fiber surface after organosolv pretreatment was studied using two different reactor types. Results from the conventional autoclave reactor suggest that redeposition occurs during the cooling down stage. Redeposited particles appeared to be spherical in shape. The size and population density of the particles depends on the concentration of organosolv lignin in the cooking liquor, which is consistent with the hypothesis that reprecipitation of lignin occurs when the system is cooled down. The use of a displacement reactor showed that displacing the spent cooking liquor with fresh cooking liquor helps in reducing the redeposition and the inclusion of a washing stage with fresh cooking liquor reduced the reprecipitation of lignin, particularly on the outer fiber surfaces. Redeposition of lignin was still observed on regions that were less accessible to washing liquid, such as fiber lumens, suggesting that complete prevention of redeposition was not achieved.
采用两种不同的反应器类型研究了木质素在有机溶剂预处理后重新沉积到纤维表面的情况。来自常规高压釜反应器的结果表明，重新沉积发生在冷却阶段。重新沉积的颗粒似乎呈球形。颗粒的大小和密度取决于蒸煮液中有机溶剂木质素的浓度，这与当系统冷却时木质素再沉淀的假设一致。使用置换反应器表明，用新鲜蒸煮液置换用过的蒸煮液有助于减少重新沉积，并且用新鲜蒸煮液进行洗涤阶段有助于减少木质素的再沉淀，特别是在纤维外表面。在洗涤液难以到达的区域，如纤维腔，仍观察到木质素的重新沉积，这表明并未完全防止重新沉积。
