The extraction kinetics and thermodynamics of decompressing inner ebullition (DIE) were investigated with the extraction of lithospermic acid B (LAB) from Salvia Miltiorrhiza Bunge as an example. Ultrasound-assisted extraction (UAE) was also performed for comparison study. A simple method was applied to determine the partition coefficient, which was used to calculate the mass transfer coefficient k, the extraction activation energy AE, and the thermodynamic properties of AH, AS and AG. The results show that the extraction process of LAB by DIE can be finished in 40 s when the operation pressure is -0.084 Mpa, the concentration of ethanol is 50%, the immersing time is 20 min, water consumption is 10 times to raw material, and the extraction temperature is in the range of 40~60℃. The extraction rate by DIE is 135 times faster than that by UAE. The mass transfer coefficient by DIE is in the range of 0.07～0.09 s-1, which is much larger than that of UAE (6.37×10-4s-1) at the same condition. The extraction activation energy AE by DIE is 7.22 kJ·mol-1 and the thermodynamic properties, AH is 28.68 kJ·mol-1, AS is 115.74 J·mol-1 and AG is -8.73 kJ·mol-1, respectively. The DIE extraction process of LAB belongs to the spontaneous process, and it is one of the fastest extraction method reported until now.%以提取丹参酚酸B为例,研究了内部沸腾法提取过程的动力学及其相关的热力学.以超声波辅助法提取作为对比,采用一种简单测定提取分配系数的方法,计算了提取过程中的传质系数k,提取过程的活化能及热力学函数△H,ΔS和ΔG.实验结果表明:在提取压力为-0.084 MPa、解吸剂乙醇浓度为50％、解吸20 min、提取用水量为物料的10倍及提取温度在40～60℃,丹参酚酸B减压内部沸腾法提取过程在40 s内完成,提取速率比超声波辅助法快135倍.减压内部沸腾法提取过程的传质系数k在0.07～0.09 s-1,远远大于超声波提取的6.37×10-4 s-1;提取过程的活化能ΔE为7.22 kJ·mol-1.丹参酚酸B减压内部沸腾法提取过程的热力学参数△H为28.68 kJ·mol-1、△S为115.74 J·mol-1、ΔG为-8.73 kJ·moi-1,为自发过程.该方法是目前报道最快的提取方法之一.
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