水热处理对杨木微观结构和降解产物的影响

田中建 吴彦 吉兴香 杨桂花 张凤山 房桂干

摘要：探讨了不同处理条件对杨木水热处理液中总木糖、乙酸、木质素含量及杨木微观结构的影响。利用单因素实验探索处理液中总木糖含量的变化规律，并以总木糖含量为指标，采用响应面法优化杨木水热处理条件。结果表明，随水热处理温度上升，木片微观孔洞增多或增大，同时表面不规则剥落和微球状沉积物不断增多，使木片比表面积先增大后减小。反应温度172.51℃，保温时间88.14 min ，固液比1∶6.06时，处理液中总木糖含量达到最优值76.54 mg/g ，木质素和乙酸含量分别为34.14 mg/g 和11.28 mg/g。

关键词：杨木;水热处理;微观形貌;工艺优化

中图分类号：TS742   文献标识码：A    DOI：10.11980/j. issn.0254-508X.2021.12.003

Effect of Hydrothermal Treatment on the Poplar Microstructure and Degradation Products

TIAN Zhongjian1，2，3   WU Yan1   JI Xingxiang1，*   YANG Guihua1   ZHANG Fengshan2   FANG Guigan3

（1. State Key Lab ofBio-based Materials and Green Papermaking，Qilu University of Technology （Shandong Academy of Sciences），Jinan，Shandong Province，250353;2. Shandong Huatai Paper Co.，Ltd.，Dongying，Shandong Province，257335;3. Institute of Chemical Industry of Forestry Products，CAF，Nanjing，Jiangsu Province，210042）

（*E-mail ：xxjt78@163. com）

Abstract ：The effects of different treatment conditions on the content of total xylose，acetic acid and lignin in the poplar hydrothermal treat? ment liquor and the microstructure of poplar wood chips were discussed . The single factor experiment was used to explore the changing law of the total xylose content in the hydrothermal treatment liquor . The total xylose content was used as an indicator to optimize the poplar hydro ? thermal treatment conditions via response surface method . The results showed that with the increase of the hydrothermal treatment tempera ? ture，the area and number of microscopic pores of the wood chips increased，whereas the number of irregular exfoliation and micro-spherical deposits on the surface of the wood chips also increased . Therefore，the specific surface area of wood chips increased first and then de ? creased. The total xylose content in the poplar hydrothermal treatment liquor reached the optimal value of 76.54 mg/g with the reaction tem ? perature of 172.51℃，the holding time of 88.14 min，and the solid-liquid ratio of 1∶6.06. The content of lignin and acetic acid were 34.14 mg/g and 11.28 mg/g，respectively.

Key words ：poplar;hydrothermal treatment;micro morphology;process optimization

隨着全球对自然资源的需求逐年升高，不可再生资源如化石资源的短缺现象日益凸显。木质纤维素类生物质是地球上最为丰富的可再生资源，其主要组分为纤维素、半纤维素、木质素、抽出物、淀粉和植物胶等[1-2]，包含五碳糖、六碳糖及芳香类化合物等有机物，这为制备不同的木质纤维素类生物质基产品提供了可能。采用生物质炼制技术对木质纤维素等可再生资源进行综合、高效、合理化利用，是应对当前全球资源消费危机、实现碳中性和绿色发展的重要方法和手段之一[3]，对我国可再生资源发展具有重要战略意义[4]。

半纤维素是木质纤维素生物质细胞壁中的一类复杂多糖，可被广泛应用于食品、医药和化学产业[5]。但半纤维素由于结构复杂多样，不易分离和纯化，利用效率较低[6-7]。……