Characterization of Switchgrass, Cellulose, Hemicellulose and Lignin for Thermochemical Conversions
Characterization of Switchgrass, Cellulose, Hemicellulose and Lignin for Thermochemical Conversions
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DOI：
10.1166/jbmb.2012.1216
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发表时间：
2012-06
影响因子：
0.5
通讯作者：
V. Pasangulapati;Ajay Kumar;C. Jones;R. Huhnke
中科院分区：
文献类型：
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作者：
V. Pasangulapati;Ajay Kumar;C. Jones;R. Huhnke
利用柳枝稷作为一种潜在的生物质原料来生产能源和燃料有很大的兴趣。热化学转化，如气化和热解，是将柳枝稷转化为能源和燃料的有效方法。研究了柳枝稷在氮气和空气条件下热化学转化的反应动力学和挥发物的变化，以及纤维素、半纤维素和木质素组分对热化学转化的贡献。为了实现这一目标，使用了热重分析仪（TGA）和傅里叶变换红外光谱仪（FTIR）。研究了柳枝稷及其组分（纤维素、半纤维素和木质素）在50℃min-1的惰性和氧化条件下的失重动力学和气体演化特征。在220 ~ 420℃的氮气气氛和220 ~ 390℃的空气气氛中，柳枝稷随升温速率的不同发生了显著的失重。各组分的失重发生在不同的温度范围内，各组分的反应活性也不同。其中，纤维素在较窄的温度范围内分解剧烈，质量损失最大；而木质素在较宽的温度范围内分解，质量损失最小。在惰性条件下，柳枝稷分解的主要最终产物是CO2、CO和CH4。与木质素相比，纤维素和半纤维素分解产生更高的CO和CO2。而大部分CH4产率是在惰性条件下由木质素分解产生的。
There is much interest in using switchgrass as a potential biomass feedstock to produce energy and fuels. Thermochemical conversions, such as gasification and pyrolysis, are efficient ways of converting switchgrass into energy and fuels. The goal of this study was to investigate reaction kinetics and volatiles evolved during thermo-chemical conversion of switchgrass under nitrogen and air conditions, and contributions of cellulose, hemicellulose and lignin components. To accomplish this, a thermogravimetric analyzer (TGA) coupled with a Fourier Transform Infrared Spectrometer (FTIR) was used. Weight loss kinetics and gas evolution profile of switchgrass, and its components (cellulose, hemicellulose and lignin) were analyzed under inert and oxidizing conditions at heating rate of 50 °C min–1. Significant weight loss of switchgrass occurred in the temperature range of 220 to 420 °C in nitrogen atmosphere and 220 to 390 °C in air atmosphere depending on heating rate. The weight loss of the components occurred in different temperature ranges and also the reactivity of each component was different from one other. Among the components, cellulose decomposed sharply in narrow temperature range with the highest mass loss; whereas lignin decomposed in a wide temperature range with the lowest mass loss. The gases CO2, CO and CH4 were identified as major end products during switchgrass decomposition in inert condition. As compared to lignin, cellulose and hemicellulose decomposition yielded higher CO and CO2. However, most of the CH4 yield was due to lignin decomposition in inert condition.