化学学报 ›› 2014, Vol. 72 ›› Issue (4): 502-507.DOI: 10.6023/A14010067 上一篇    

研究论文

果糖一步水热合成碳微球固体酸催化纤维素水解

廉优芬, 闫碌碌, 王羽, 漆新华   

  1. 天津市生物质类固废资源化技术工程中心 南开大学环境科学与工程学院 天津 300071
  • 收稿日期:2014-01-25 出版日期:2014-04-14 发布日期:2014-03-29
  • 通讯作者: 漆新华 E-mail:qixinhua@nankai.edu.cn E-mail:qixinhua@nankai.edu.cn
  • 基金资助:

    项目受国家自然科学基金(No.21350110210)、教育部新世纪人才计划和天津市自然科学基金(No.12JCYBJC13000)资助.

One-step Preparation of Carbonaceous Solid Acid Catalysts by Hydrothermal Carbonization of Fructose for Cellulose Hydrolysis

Lian Youfen, Yan Lulu, Wang Yu, Qi Xinhua   

  1. Tianjin Biomass Solid Waste Reclamation Technology and Engineering Center, College of Environmental Science and Engineering, Nankai University, Tianjin 300071
  • Received:2014-01-25 Online:2014-04-14 Published:2014-03-29
  • Supported by:

    Project supported by the National Natural Science Foundation of China (No. 21350110210), the Program for New Century Excellent Talents in University, and the Natural Science Foundation of Tianjin (No. 12JCYBJC13000).

纤维素水解是生物质资源转化利用中最关键的一步. 通过硫酸浸渍活性炭方法制备的磺酸基功能化活性炭是目前纤维素水解反应中应用最为广泛的固体酸之一,但这种方法存在严重的环境污染问题. 我们利用果糖的水热碳化,在150 ℃的温和条件下合成了一种新型的富含羧基和羟基的碳微球固体酸,在离子液体1-丁基-3-甲基咪唑氯盐[BMIM][Cl]溶剂体系中,该碳微球可以有效地将纤维素水解(130 ℃,反应3 h,还原糖产率45.6%). 为了进一步提高碳微球固体酸的活性,以磺基水杨酸为共聚物,利用果糖的水热碳化反应,通过一步水热法合成了含有磺酸基的碳微球固体酸催化剂. 系统研究了该催化剂作用下反应温度、反应时间、催化剂使用量、水的添加量以及纤维素起始浓度等因素对纤维素催化水解的影响. 在[BMIM][Cl]溶剂中,纤维素水解的还原糖产率提高到了60.7% (130 ℃,反应90 min),且催化剂循环5次后仍能保持良好催化活性. 本工作利用果糖一步水热法制备碳微球固体酸,并将其应用于纤维素的高效水解,为生物质资源的高值化提供了一条新路径.

关键词: 水热碳化, 碳微球, 固体酸, 水解, 纤维素

Hydrolysis of cellulose plays a key role in the biomass utilization. As a commonly used solid acid in cellulose hydrolysis, sulfated activated carbon normally prepared from the impregnation of activated carbon by sulfuric acid does not meet the principles of green chemistry and leads to environmental issues. In this work, carbonaceous microshperes bearing COOH, OH groups were synthesized by hydrothermal carbonization of fructose at 150 ℃ for 4 h, and the obtained carbonaceous material could be used directly for the catalytic hydrolysis of cellulose without any post-modification or in-situ functionalization, where a reducing sugar yield of 45.6% was obtained at 130 ℃ in 3 h in ionic liquid 1-butyl-3-methylimidazolium chloride ([BMIM][Cl]). To improve the catalytic activity of the carbonaceous solid acid catalyst, sulfonic groups were grafted onto the carbonaceous microspheres by one-step hydrothermal carbonization of fructose in the presence of sulfosalicylic acid as co-monomer. The effects of reaction temperature, reaction time, catalyst dosage, water content and initial cellulose concentration on the hydrolysis of cellulose were systematically investigated in the presence of the as-prepared sulfonated carbonaceous solid acid catalyst, and the reducing sugar yield for cellulose hydrolysis was improved to 60.7% at 130 ℃ in 90 min in [BMIM][Cl]. An appropriate water content of around 1% in the ionic liquid could promote the formation of the reducing sugars, whereas a water content of greater than 1% lead to a decrease in the yield of reducing sugars. No large decrease in the yield of reducing sugars could be observed for initial cellulose concentration (w) of up to 10%. The catalyst could be reused and exhibited constant stability for at least five successive trials. The method developed offers a new way for the preparation and in-situ functionalization of carbonaceous solid acid catalysts, and provides a renewable strategy for the sustainable biomass utilization.

Key words: hydrothermal carbonization, carbonaceous microspheres, solid acid, hydrolysis, cellulose