减压水提工艺中真空度的影响因素考察

Investigation of Influencing Factors for Vacuum in Water Vacuum Extraction Process

目的:研究减压水提取工艺中沸点与真空度的相关性,并比较不同药材加入量对真空度及摩尔汽化热的影响。方法:采用理论计算和减压试验测定相结合的方法,获取不同沸点下真空度,计算该体系饱和蒸汽压值和平均摩尔汽化热。结果:纯溶剂真空度实测值较理论值有变化;加入药材后真空度实测值较纯溶剂真空度实测值偏小,平均摩尔汽化热实测值较纯溶剂实测值小;药材加入量对真空度实测值无显著影响。结论:加入药材对水减压提取工艺中真空度的控制不会产生实质性影响。

Objective：To study correlation between boiling point and vacuum in vacuum water extraction technology,and compare effects of different medicinal dosage on the vacuum and the average molar heat of vaporization.Method：Theoretical calculation and decompression test determination were used to obtain the vacuum at different boiling point.Then the saturated vapor pressure value and the average molar heat of vaporization in this system were calculated.Result：There are changes between the measured and theoretical values of vacuum with the pure solvent;After added medicinal materials,the measured values of vacuum were lower than the measured values of the pure solvent,the measured values of the average molar heat of vaporization were lower than the values of the pure solvent.Effects of medicinal dosage on the measured value of vacuum had no significant.Conclusion：There was no substantive impact on vacuum control in water vacuum extraction process by adding Chinese medicines.