作　　者： ; ; ;

机构地区： 天津科技大学食品工程与生物技术学院

出　　处： 《高校化学工程学报》 2005年第5期583-587,共5页

摘　　要： 从实验和理论上对超声强化超临界流体萃取的机理进行了研究。采用自行设计的内插式超声强化超临界流体萃取装置,运用数码显微成像系统和透射电镜观察了有、无超声作用下超临界流体萃取中空化测试材料和海藻细胞微观结构的前后变化,分析了超声对超临界流体萃取海藻中二十碳五烯酸(EPA)和二十二碳六烯酸(DHA)的传质和萃取率的影响,并根据声化学原理对超临界流体中附加超声场时能否产生空化现象进行了探讨。实验结果发现超声对超临界二氧化碳流体中的空化材料和海藻细胞壁不产生破坏作用,不会产生声空化效应,但提高了海藻中EPA和DHA的萃取传质效果。其实验结果与理论推导相一致。结果表明:超声强化超临界流体萃取的机理不是源于超声空化,而是超声在微环境内产生的机械波动效应和热效应。 The extraction mechanism of ultrasound-enhanced supercritical fluids was studied theoretically and experimentally. With the help of self-designed interpolated ultrasound-enhanced supercritical fluids extraction （USFE） device, the digital camera and TEM, the variances of cavitation test material and marine algae cell microstructure occurred by adding the ultrasonic during supercritical fluids extraction （SFE） were observed and the mass transfer and extraction yield of EPA and DHA of marine algae in USFE were also studied. Based on sonochemistry principles, the problem whether cavitation phenomenon in USFE can be occurred was discussed. The ultrasonic in SFE does not destroy the cavitation test material and the marine algae cell microstructure, that is, no cavitation effect is emerged; but the mass transfer of extraction is increased instead. The experimental results agree with the theoretic deduction. The results show that the extractive enhancement mechanism in USFE is primarily mechanical fluctuant effect and thermal effect of ultrasonic in microenvironment rather than that of cavitary effect.

关 键 词： 超声强化 超临界流体萃取 空化效应 机理

领　　域： [化学工程]