超临界CO_2萃取沙棘油的实验研究及数值模拟

Experimental Research and Simulation of Supercritical CO_2 Extraction of Seed Oils from Hippophae Rhamnoides L.

本文利用超临界CO2萃取沙棘油,建立了一套实验流程,分别考察了萃取压力、萃取温度以及颗粒大小对萃取率的影响。同时根据萃取器单元的质量守恒建立了微分方程,并对一定萃取条件下的实验结果进行数值模拟。结果表明, 本文所建立的数值模型能较好地描述实际萃取行为。

Extraction of oil from crushed Hippophae Rhamnoides L. seeds with supercritical CO2 was performed over the pressure range 15~30MPa and temperature ragne 303~318K in a laboratory apparatus of 1L volume. The CO2 flow rate was 0.2m3h-1. During the extraction from milled seeds, the easily accessible solute from the cells opened by milling is extracted first, and the slower extraction of the solute protected by the cell walls follows. A mathematical model of the supercritical extraction process was developed on the basis of the differential mass balances performed along the extraction bed. The equilibrium between the solid and the fluid phases appeared to be the controlling step during the extraction process. A good fitting of the experimental data was obtained by use of the model when K=10.