烟叶低温裂解挥发油的GC-MS检测及组分分析

Determination and Component Analysis of Volatile Oil from Low-Temperature Pyrolysis of Tobacco Leaves by GC-MS

摘要: 本文以烟草为研究对象，采用管式炉热解反应收集250℃、300℃、400℃下的烟草裂解挥发油，以热解温度和溶剂为影响因素，以生成香气化合物的类型和含量为评价标准，进行气相色谱–质谱(GC-MS)分析。结果表明：1) 挥发油中的化学成分随着温度的上升大致呈先上升后下降的趋势，低温250℃有利于芳香类化合物的生成，特别是杂环类与醛酮类等主要香味物质。2) 二氯甲烷对裂解油中香气物质的萃取效果优于环己烷和石油醚(60~90℃)，对香气物质的最大萃取得率为30.72%。3) 烟碱在高温下通过二次分解转化为含氮杂环化合物。由于生物油中氮的含量较高，杂环是生物油中含量最多的组分，其次是醛酮类组分。4) 此外，由于生物油产量较高，烟叶可用于生产芳香化合物，烷烃类产物较多，废弃烟草也可作为生物质燃料。

Abstract: In this paper, tobacco was taken as the research object, and the pyrolysis reaction of the tube furnace was used to collect the volatile oil of tobacco pyrolysis at 250˚C, 300˚C, and 400˚C. The pyrolysis temperature and solvent were the influencing factors, and the types and contents of the aroma compounds of the volatile oil were used as the evaluation criteria for Gas Chromatography-Mass Spectrometry (GC-MS) analysis. The results showed that: 1) The chemical com-ponents in the volatile oil generally showed a trend of first increasing and then decreasing with the increase of temperature, and the low temperature of 250˚C was conducive to the formation of aromatic compounds, especially the main aroma compounds such as heterocycles and aldehydes and ketones. 2) The extraction effect of dichloromethane on aroma substances in pyrolysis oil was better than that of cyclohexane and petroleum ether (60~90˚C), and the maximum extraction rate of aroma substances is 30.72%. 3) Nicotine was converted into nitrogen-containing heterocyclic compounds through secondary decomposition at high temperatures. Due to the high content of nitrogen in bio-oil, heterocycles were the most abundant components in bio-oil, followed by aldehydes and ketones. 4) In addition, due to the high yield of bio-oil, tobacco leaves can be used to produce aromatic compounds, and there were more alkane products, and waste tobacco can also be used as biomass fuel.