Abstract The aim of this study was to investigate the effects of temperature and reaction time on the primary pyrolysis of cellulose and xylan. Fast pyrolysis of cellulose and xylan was carried out with a micropyrolyser connected to a gas chromatograph-mass spectrometer/flame ionisation detector (GC–MS/FID) to separate and identify volatile components, both qualitatively and quantitatively. This set-up meant a minimum amount of secondary reactions, low impact of the heating period and at the same time provided rapid and accurate analyses. The two biomass components investigated were: cellulose and hemicellulose (represented by xylan). They were pyrolysed during 0.5, 1, 2 and 5 s (s) and within a temperature range of 400–600 °C. The results showed that levoglucosan (1, 6-anhydro β-D-glucopyranose) is the main chemical compound released during cellulose pyrolysis. It increased with increasing temperature and time. The main volatile compounds produced from pyrolysis of xylan are: 1-hydroxy-2-butanone, 4-hydroxy-5, 6-dihydro-(2 H)-pyran-2-one, 1-hydroxy-2-propanone (acetol), acetaldehyde and hydroxyacetaldehyde (HAA). HAA was the most abundant chemical compound released during xylan pyrolysis, increasing with higher temperatures and time. Acetol and acetaldehyde also showed similar behaviour. The chemical compounds released from cellulose and xylan fast pyrolysis are primary products and assumed to be produced directly from both cellulose and xylan molecules and not from secondary degradation. In this study, possible reaction routes during biomass primary pyrolysis are also suggested based on the product distribution from the thermal decomposition of cellulose and xylan.

中文翻译：

---

温度和时间对纤维素和木聚糖初始热解的影响

摘要 本研究的目的是研究温度和反应时间对纤维素和木聚糖初级热解的影响。纤维素和木聚糖的快速热解是通过与气相色谱-质谱仪/火焰电离检测器 (GC-MS/FID) 连接的微热解器进行的，以定性和定量地分离和识别挥发性成分。这种设置意味着最少的二次反应、加热期的低影响，同时提供快速和准确的分析。研究的两种生物质成分是：纤维素和半纤维素（以木聚糖为代表）。它们在 0.5、1、2 和 5 s (s) 期间在 400–600 °C 的温度范围内热解。结果表明，左旋葡聚糖(1, 6-脱水 β-D-吡喃葡萄糖）是纤维素热解过程中释放的主要化合物。它随着温度和时间的增加而增加。木聚糖热解产生的主要挥发性化合物有：1-羟基-2-丁酮、4-羟基-5、6-二氢-(2 H)-吡喃-2-酮、1-羟基-2-丙酮(丙酮醇) 、乙醛和羟基乙醛 (HAA)。HAA 是木聚糖热解过程中释放的最丰富的化合物，随着温度和时间的升高而增加。丙酮醇和乙醛也表现出类似的行为。纤维素和木聚糖快速热解释放的化合物是初级产品，假定直接由纤维素和木聚糖分子产生，而不是二次降解。在这项研究中，