In this study, enzymatic hydrolysis lignin (EHL) extracted from bio-ethanol production residue by enzymatic hydrolysis method was utilized as the raw material, which was subsequently purified to remove cellulose and hemicellulose for gaining the purified lignin (EHL-P) through alkaline solution extraction. Compared with EHL-P, thermal performance and pyrolytic product distribution of EHL-P-SE (which was obtained from EHL-P by steam explosion) were also analyzed by thermogravimetric analyzer coupled with Fourier transform infrared spectroscopy (TG-FTIR) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). Results showed that the degradation process of EHL-P and EHL-P-SE was similarly divided into three stages: a drying stage, a rapid decomposition stage, and a slow carbonization stage. However, their initial weight loss (i.e., ˂ 3 wt% for EHL-P, while ~ 5 wt% for EHL-P-SE before 200 °C), primary weight loss (i.e., ~ 55 wt% for EHL-P, while ~ 48 wt% for EHL-P-SE between 200 and 600 °C), and char yields (i.e., ~ 33 wt% for EHL-P, while ~ 42 wt% for EHL-P-SE at 900 °C) were different. FTIR showed that the evolution of gaseous products changed significantly due to the effect of SE treatment, especially for organic components (i.e., the absorbance of peaks corresponding to carbonyl-containing components such as aldehydes, ketones, and acids decreased, while that related to phenols and aromatics increased). Finally, Py-GC/MS tracked variations of the relative content (%) of phenols (e.g., guaiacol (G), phenol (P), syringol (S), and catechol (C) types) with the increase of degradation temperature (from 300 to 500 °C), and results showed that demethoxylation was more likely to occur at higher degradation temperatures (≥ 400 °C) to realize the transformation from G- and S-type phenols to P- and C-type phenols.

本研究以酶解法从生物乙醇生产残渣中提取的酶促水解木质素（EHL）为原料，对其进行纯化以去除纤维素和半纤维素，从而通过碱性溶液获得纯化的木质素（EHL-P）。萃取。与EHL-P相比，还通过热重分析仪，傅立叶变换红外光谱（TG-FTIR）和热解-热分析仪分析了EHL-P-SE（通过蒸汽爆炸从EHL-P获得）的热性能和热解产物分布。气相色谱/质谱（Py-GC / MS）。结果表明，EHL-P和EHL-P-SE的降解过程类似地分为三个阶段：干燥阶段，快速分解阶段和缓慢碳化阶段。但是，他们最初的体重减轻（即 EHL-P为3 wt％，而200°C之前为EHL-P-SE〜5 wt％），一次失重（即，EHL-P为〜55 wt％，而EHL-P为〜48 wt％ -SE在200至600°C之间）和焦炭收率（即在900°C下EHL-P为〜33 wt％，而EHL-P-SE为〜42 wt％）是不同的。FTIR表明，气态产物的演化由于SE处理的影响而发生了显着变化，特别是对于有机组分（即，与含羰基组分（如醛，酮和酸）相对应的峰的吸光度下降，而与酚有关的峰和芳烃增加）。最后，Py-GC / MS跟踪了降解温度升高时苯酚（例如，愈创木酚（G），苯酚（P），丁香酚（S）和儿茶酚（C）类型）的相对含量（％）的变化（ 300至500°C），