Abstract The inherent disadvantages such as high oxygen content, low energy density, high moisture adsorption propensity and high spontaneous combustion tendency, have limited the widespread utilization of lignocellulosic biomass. A novel degradative solvent extraction (DSE) method has been recently developed to deoxygenate and upgrade biomass into two high-quality extracts (Soluble and Deposit) with various high-value applications. However, the moisture adsorption and spontaneous combustion characteristics of Soluble and Deposit still remain unclear, which are important for the safe storage, transportation and subsequent application of Soluble and Deposit. Therefore, in this study, the moisture adsorption and spontaneous combustion characteristics of Soluble, Deposit as well as raw biomass were investigated and compared. The moisture adsorption ratios of Soluble and Deposit were lower than 1.5% and 2.5% respectively, which were significantly lower than that of raw biomass, indicating that degradative solvent extraction greatly inhibited the moisture adsorption propensity of biomass. The ignition temperatures of Soluble and Deposit were at least 110 °C higher than that of raw biomass, and the activation energy of low temperature oxidation of Soluble and Deposit were 1.2–2.0 times higher than that of raw biomass. Soluble and Deposit had much higher weight loss temperature, heat release temperature, ignition temperature and higher activation energy of low temperature oxidation, revealing that the spontaneous combustion tendency of Soluble or Deposit was also significantly suppressed in comparison with raw biomass. The physicochemical properties of raw biomass, Soluble and Deposit were detailedly characterized, and it can be concluded that the low content of oxygen-containing functional groups, poor pore structure and dense surface structure jointly suppressed the moisture adsorption propensity and spontaneous combustion tendency of biomass after degradative solvent extraction. This research proves that degradative solvent extraction could not only achieve the upgrading of biomass but also inhibit the moisture adsorption propensity and spontaneous combustion tendency of biomass.

中文翻译：

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降解溶剂萃取后生物质废弃物的吸湿及自燃特性

摘要 木质纤维素生物质具有氧含量高、能量密度低、吸湿性强、自燃倾向高等固有缺点，限制了其广泛利用。最近开发了一种新的降解溶剂萃取 (DSE) 方法，用于将生物质脱氧并将其升级为两种具有各种高价值应用的高质量提取物（可溶性和沉积物）。然而，Soluble和Deposit的吸湿性和自燃特性仍不清楚，这对Soluble和Deposit的安全储存、运输和后续应用具有重要意义。因此，在本研究中，研究和比较了可溶生物质、沉积物以及生物质的水分吸附和自燃特性。Soluble和Deposit的吸湿率分别低于1.5%和2.5%，明显低于生物质的吸湿率，表明降解溶剂萃取极大地抑制了生物质的吸湿倾向。Soluble 和Deposit的着火温度至少比生物质高110 ℃，Soluble 和Deposit的低温氧化活化能比生物质高1.2-2.0倍。Soluble 和Deposit具有更高的失重温度、放热温度、着火温度和更高的低温氧化活化能，表明Soluble 或Deposit的自燃倾向也比生物质显着受到抑制。生物质的理化性质，对可溶性和沉积物进行了详细表征，可以得出结论，含氧官能团含量低、孔隙结构差和表面结构致密共同抑制了降解溶剂提取后生物质的吸湿倾向和自燃倾向。本研究证明降解溶剂提取不仅可以实现生物质的升级，而且可以抑制生物质的水分吸附倾向和自燃倾向。