Augmented Leaching Pretreatments for Forest Wood Waste and Their Effect on Ash Composition and the Lignocellulosic Network
Augmented Leaching Pretreatments for Forest Wood Waste and Their Effect on Ash Composition and the Lignocellulosic Network
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DOI：
10.1021/acssuschemeng.0c00351
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发表时间：
2020-04-13
影响因子：
8.4
通讯作者：
Skoulou, Vasiliki
中科院分区：
文献类型：
--
作者：
Taylor, Martin J.;Alabdrabalameer, Hassan A.;Skoulou, Vasiliki
通过增强传统浸出技术从木质纤维素废渣中去除灰分成分，可以为生物质供给、反流化和反应器腐蚀等关键工业问题提供更清洁、节能的解决方案。人们发现，通过将物理化学技术与传统浸出相结合，不仅可以有效去除无机成分（灰分），而且可以改变木质纤维素基质内的分子间相互作用，如可变结晶度指数（粉末 X 射线衍射）所示，而不损失物理键合（傅里叶变换红外光谱）。最终，这使得所使用的所有技术都能实现纤维素、半纤维素和木质素更大的热化学转化：传统浸出、间接/定向超声波和微波辐射。然而，使用定向超声波被发现是一种出色的节能技术（8.6 kJ/g），可以从根本上改善木材废料的热化学转化，特别是在高温下减少固定碳方面。人们还发现，它可以有效去除重要的共晶混合物形成元素，包括众所周知的难以通过浸出去除的硅。相比之下，热板浸出和微波辐射分别消耗 39 倍和 116 倍的能量。与目前不适合大规模运营的微波替代方案相比，由于其可扩展性，将该技术集成到能源生产领域将在未来变得至关重要。此外，与其他各种物理化学技术相比，定向超声所需的停留时间可以忽略不计，为 0.1 小时，而为 4 小时。
By augmenting conventional leaching technologies for the removal of ash constituents from lignocellulosic waste residues, a cleaner and energy efficient solution can be provided for critical industrial problems such as biomass feeding, defluidization, and reactor corrosion. It has been found that not only are inorganic constituents (ash) effectively removed by coupling a physicochemical technology with conventional leaching but also the intermolecular interactions within the lignocellulosic matrix can be modified, as shown by a variable crystallinity index (powder X-ray diffraction) without the loss of physical bonding (Fourier-transform infrared spectroscopy). Ultimately, this allowed for a greater thermochemical transformation of cellulose, hemicellulose, and lignin for all technologies used: conventional leaching, indirect/directed ultrasound, and microwave irradiation. However, the use of directed ultrasound was found to be the standout, energy efficient technology (8.6 kJ/g) to radically improve the thermochemical transformation of wood waste, especially in the reduction of fixed carbon at high temperatures. It was also found to be efficient at removing vital eutectic mixture causing elements, including Si, which is known to be notoriously difficult to remove via leaching. In comparison, hot plate leaching and microwave irradiation use 39 and 116 times more energy, respectively. The integration of this technology into the energy production sector will prove vital in the future due to its scalability, as compared with microwave alternatives, which are currently not suitable for large scale operations. Additionally, the residence time required for directed ultrasound was found to be negligible as compared to the various other physicochemical techniques, 0.1 h opposed to 4 h.