论文部分内容阅读
利用热重红外分析仪(TG-FTIR)对木质素进行热重分析及主要气相产物分析,结合红外光谱对木质素不同热解阶段生成的半焦进行研究。实验结果表明:木质素热解分为3个阶段,200℃以下为自由水挥发过程;200~550℃为主要热解阶段,此过程中木质素苯环周围的官能团发生断裂,析出部分气体产物及焦油产物;550~900℃过程中,苯环发生解链或芳香缩聚成碳。通过FTIR的研究发现,木质素热解过程中,析出的主要气体包括H2O、CO2、CO以及烃类产物CH4等,CO2析出存在2个温度区间低温段(250~450℃)和高温段(650~750℃),而CO在高温段大量生成,CH4的析出主要集中在在300~600℃温度区间。
Thermal gravimetric analysis (TG-FTIR) and primary gas-phase analysis of lignin were carried out by TG-FTIR. The semi-coke produced by different pyrolysis stages of lignin was studied by infrared spectroscopy. The experimental results show that the pyrolysis of lignin is divided into three stages, the free water volatilization process is below 200 ℃, the main pyrolysis stage is from 200 ℃ to 550 ℃, the functional groups around the lignin benzene ring rupture during the process, some gas products are precipitated And tar products; during the process of 550-900 DEG C, the benzene ring is melted or condensed into carbon by aromatic condensation. FTIR study found that during the pyrolysis of lignin, the major gases precipitated include H2O, CO2, CO and hydrocarbon products such as CH4. There are two temperature ranges of 250 ~ 450 ℃ and 650 ~ 750 ℃), while CO was generated in a large amount at high temperature. The precipitation of CH4 mainly concentrated in the temperature range of 300 ~ 600 ℃.