Guangxi Key Laboratory of Green Processing of Sugar Resources (Guangxi University of Science and Technology), Liuzhou 545006, China; Province and Ministry Co-sponsored Collaborative Innovation Center of Sugarcane and Sugar Industry, Nanning 530004, China.
Guangxi Key Laboratory of Green Processing of Sugar Resources (Guangxi University of Science and Technology), Liuzhou 545006, China; Province and Ministry Co-sponsored Collaborative Innovation Center of Sugarcane and Sugar Industry, Nanning 530004, China.
Ultrason Sonochem. 2022 Jan;82:105886. doi: 10.1016/j.ultsonch.2021.105886. Epub 2021 Dec 27.
The effect of ultrasound on the kinetics of anti-solvent crystallization of sucrose was studied. The influence of temperature, stirring rate, supersaturation and ultrasonic power on the anti-solvent crystallization of sucrose was investigated. The relationship between infrared spectral characteristic band of sucrose and supersaturation was determined with an online reaction analyzer. The crystal size distribution of sucrose was detected by a laser particle-size analyzer. Ultrasound accelerated the crystallization process, and had no impact on the crystal shape. Abegg, Stevens and Larson model was fitted to the experimental data, and the results were the following: At 298.15 K, the average size of crystals was 133.8 μm and nucleation rate was 4.87 × 10 m·s without ultrasound. In an ultrasonic field, the average size was 80.5 μm, and nucleation rate was 1.18 × 10 m·s. Ultrasound significantly reduced the average size of crystals and improved the nucleation rate. It was observed that the crystal size decreased with the increase of stirring rate in silent environment. When the stirring rate increased from 250 to 400 rpm, the average size decreased from 173.0 to 132.9 μm. However, the stirring rate had no significant impact on the crystal size in the ultrasonic field. In addition, the activation energy of anti-solvent crystallization of sucrose was decreased, and the kinetic constant of nucleation rate was increased due to the effect of ultrasound. In the ultrasonic field, the activation energy was reduced from 20422.5 to 790.5 J·mol, and the kinetic constant was increased from 9.76 × 10 to 8.38 × 10.
超声对蔗糖抗溶剂结晶动力学的影响。考察了温度、搅拌速率、过饱和度和超声功率对蔗糖抗溶剂结晶的影响。采用在线反应分析仪确定了蔗糖红外光谱特征带与过饱和度的关系。采用激光粒度分析仪检测了蔗糖的晶体粒度分布。超声加速了结晶过程,但对晶体形状没有影响。用 Abegg、Stevens 和 Larson 模型对实验数据进行拟合,结果如下:在 298.15 K 下,无超声时晶体平均粒径为 133.8 μm,成核速率为 4.87×10 m·s。在超声场中,平均粒径为 80.5 μm,成核速率为 1.18×10 m·s。超声显著减小了晶体的平均粒径,提高了成核速率。在安静环境中,观察到晶体尺寸随搅拌速率的增加而减小。当搅拌速率从 250 增加到 400 rpm 时,平均粒径从 173.0 减小到 132.9 μm。然而,在超声场中,搅拌速率对晶体尺寸没有显著影响。此外,由于超声的作用,蔗糖抗溶剂结晶的活化能降低,成核速率的动力学常数增加。在超声场中,活化能从 20422.5 降低到 790.5 J·mol,动力学常数从 9.76×10增加到 8.38×10。