Abstract The heterogeneity of the heavy fraction in bio-oil (HBO) causes serious problem for its downstream utilization. A multi-step method is thus proposed to separate different chemical groups from HBO. In this study, HBO from fast pyrolysis of poplar wood was collected and the characteristics of the HBO were investigated. A series of separation experiments was conducted on HBO, whose chemical groups were analyzed by chromatography coupled with mass spectrometry. The results show that through primary pH adjustment and CH2Cl2 extraction, HBO is divided into two fractions with fewer types of chemicals. After further distillation, HBO is separated into four fractions, whose primary chemical groups and their peak area percentages are ketones (89.5%), esters (49.9%), aromatic hydrocarbons (63.8%) and phenols (39.2%), respectively. These fractions can be used efficiently for either upgrading towards fuels or purification towards valuable chemicals. The findings in this paper is hoped to shed a light on solving the heterogeneity problem of bio-oil.

中文翻译：

---

生物质快速热解油重馏分不同化学基团的多步分离

摘要 生物油（HBO）中重馏分的异质性给其下游利用带来了严重的问题。因此提出了一种多步骤方法来从 HBO 中分离不同的化学基团。在这项研究中，收集了杨木快速热解产生的 HBO 并研究了 HBO 的特性。对HBO进行了一系列分离实验，其化学基团通过色谱和质谱联用进行了分析。结果表明，通过初步 pH 调节和 CH2Cl2 萃取，HBO 被分成两个化学物质类型较少的部分。进一步蒸馏后，HBO 被分离成四个馏分，其主要化学基团和峰面积百分比分别为酮 (89.5%)、酯 (49.9%)、芳烃 (63.8%) 和酚 (39.2%)。这些馏分可以有效地用于升级为燃料或纯化为有价值的化学品。本文的研究结果有望为解决生物油的异质性问题提供启示。