Substitution of fossil energy sources for bio-based ones will require development of efficient processes that can convert inedible and preferably low-value fractions that currently are not used into high-value products. It is desirable that such processes are developed so that both current logistics and infrastructure can be used. Bark, which is the outer layer of woody biomass, is currently burnt in a low-value process or left in the forests to decay and is therefore considered waste. In this work, birch (Betula pendula) bark was converted to hydrocarbons suitable for use in both road and aviation fuels in two efficient steps. Development of an efficient, recyclable, salt- and metal-free solvent-based system to solubilize birch bark under benign reaction conditions was a key outcome. The obtained gum was composed of organosolv lignin and suberin oligomers and was fully characterized. This gum had unique properties and could be directly processed in a conventional hydroprocessing unit set-up to afford hydrocarbons in the road and aviation fuel ranges. Life cycle assessment was applied to evaluate different scenarios for implementing this technology. When using bark generated as a forestry by-product and current infrastructure in a pulp mill, the process had a favorable low carbon dioxide footprint for biofuel generation.

中文翻译：

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白桦树皮转化为生物燃料

用化石能源替代基于生物的能源将需要开发有效的流程，该流程可以将目前不使用的不可食用的，最好是低价值的馏分转化为目前未使用的高价值产品。期望开发这样的过程，以便可以使用当前的物流和基础设施。树皮是木质生物质的外层，目前以低价值流程燃烧或留在森林中腐烂，因此被视为浪费。在这项工作中，桦木（Betula pendula）树皮通过两个有效步骤被转化为适用于道路和航空燃料的碳氢化合物。关键的结果是，开发一种有效，可回收，无盐和无金属的溶剂型系统，以溶解白桦树皮。所获得的胶由有机溶剂木质素和木栓质低聚物组成，并被充分表征。这种口香糖具有独特的性能，可以在常规加氢处理装置中直接加工，以提供道路和航空燃料范围内的碳氢化合物。生命周期评估用于评估实施该技术的不同方案。当使用树皮作为制浆厂的林业副产品和当前基础设施时，该工艺可产生有利的低二氧化碳足迹，用于生物燃料的生产。