[BMIM]HSO_(4)对再生木质素的物化结构及热行为的影响

Effect of[BMIM]HSO_(4) on physicochemical structure and thermal behavior of regenerated lignin

探究离子液体溶解处理对再生木质素物化结构和热行为的影响.以1-丁基-3-甲基咪唑硫酸氢盐([BMIM]HSO_(4))溶解处理后的再生木质素为研究对象,通过元素分析、XRD、FTIR、SEM等手段对其结构和组成进行表征,并利用热重分析仪和分布活化能模型分析其热失重过程,考查溶解温度和时间对[BMIM]HSO_(4)再生木质素结构和热失重过程的影响.结果表明:在木质素再生过程中由于[BMIM]HSO_(4)的占位作用,有效调整了木质素分子的排列方式.[BMIM]HSO_(4)处理后的再生木质素的热失重过程与原木质素发生明显差异,向高温段移动.经分布活化能模型计算分析表明再生木质素热失重过程的活化能高于木质素原料,[BMIM]HSO_(4)溶解处理后木质素热稳定性提高.该研究为木质素的资源化应用技术开发提供了一定的理论参考.

The effect of ionic liquid dissolution treatment on the thermal behavior of regenerated lignin was investigated.Taken regenerated lignin pretreated by 1-butyl-3-methylimidazole hydrogen sulfate([BMIM]HSO_(4))as the research object,the structure and composition of regenerated lignin were characterized by elemental analysis,XRD,FTIR,SEM.The thermal weight loss process of regenerated lignin was analyzed using a thermogravimetric analyzer and a distributed activation energy model.The effects of dissolution temperature and time on the structure and thermal weight loss process of[BMIM]HSO_(4) regenerated lignin were investigated.The results showed that the arrangement of lignin molecules is effectively adjusted during the lignin regeneration process,due to the occupying effect of[BMIM]HSO_(4).Compared with lignin raw materials,the thermal behavior of[BMIM]HSO_(4) regenerated lignin all shift towards the high-temperature range.Based on the calculation and analysis of the distributed activation energy model,the activation energy during the thermal weight loss process of regenerated lignin is higher than that of lignin raw materials.After the dissolution treatment of[BMIM]HSO_(4),the thermal stability of lignin is improved.The theoretical reference is provided for the development of lignin resource utilization technology.