稀酸预处理玉米芯提取木糖的研究

通过单因素实验法和正交实验法优化了以玉米芯为原料制备木糖实验过程中各工艺参数,包括固液比、酸浓度、处理温度以及处理时间。结果表明,稀酸预处理过程各因素对玉米芯木糖提取率影响程度由大到小的顺序为:处理温度酸浓度处理时间。且在降低酸浓度和减少反应时间的情况下,仍可使木糖得率达到较高的水平,优化的实验条件为:固液比1∶10,酸浓度1. 2%,处理温度120°C,处理时间90 min。在此条件下,木糖得率可达86. 36%。     

纤维素水解制备葡萄糖的研究进展

作为纤维素高值化利用的重要一环,现今纤维素水解糖化的效率并不高,原因主要集中于催化剂催化效果不佳和葡萄糖分离困难两方面。本文详细综述了目前有关纤维素水解制备葡萄糖的多种途径以及相关研究进展,对未来纤维素水解糖化方法的改进具有一定的参考价值。     

制备L-阿拉伯糖的多元集成反应分离装备开发

针对用木糖母液和玉米皮水解液通过色谱分离来制取L-阿拉伯糖的传统工艺,提出了一种将其水解反应和色谱连续分离进行过程耦合调控的新工艺,并应用最新机电一体化控制技术,成功开发出制备L-阿拉伯糖的多元分流式反应分离集成装备。该类新型装备流程简洁、结构紧凑、自动化程度高、性能稳定可靠,具有较显著的节能减排效果,符合现代轻工机械最新发展方向,值得应用与推广。     

Maltose hydrogenation to maltitol over industrial Raney Ni catalyst: Kinetics and mechanism

The kinetics and mechanisms of selective maltose hydrogenation over Raney Ni remain poorly understood, which hinders the industrial advancement of maltitol production for biorefining. Herein, the impact of hydrogenation conditions and in-depth mechanistic characterizations were carefully investigated in this research. Optimization of reaction conditions illustrated that maltitol formation was favored by moderate reaction temperatures (≤130°C), high hydrogen pressures (>7 MPa), and near-neutral sodium phosphate buffer (pH = 6.47). Kinetic studies demonstrated the E_a of 45.5 kJ/mol for the hydrogenation of maltose. The in situ IR revealed that the hydrogenation of maltose over Raney Ni occurs in the order of ring opening and adsorption via CO of the aldose form followed by hydrogenation. The UV–vis spectra demonstrated the near-neutral setting (pH = 6.47) promoted the production of open-chain aldose conformation and selective CO hydrogenation to the corresponding alcohols. The present study on concentrated-maltose hydrogenation paves the way for the industrial development of maltitol manufacturing.