关键词: 红松松针, 甾醇, 超临界二氧化碳, 动力学, 热力学

Abstract: [Objective] Effects of supercritical carbon dioxide extraction sterol from Korean pine needles were investigated, and the related kinetics and thermodynamics were evaluated, the result could provide theoretical reference for the extraction of effective components from plants with supercritical carbon dioxide.[Method] With the yield of sterol as index, based on the single factor experiment result, the effects of extraction pressure and extraction time on the extraction of sterol were discussed, and the extraction process was fitting and verified.[Result] The optimum extraction process was as follows:the particles sizes of pine needles were 80 meshes, extraction pressure was 25 MPa, carbon dioxide flow was 20 L·h^-1 and extraction temperature was 60℃, and the yield of sterol was (40.00±1.23) mg·(100 g) ^-1 under the optimum conditions. The kinetic analysis indicated that ExpDec1 model (R² ≥ 0.958 4) was the best one to fit the extraction course when the extraction pressure was 10, 15 and 25 MPa respectively. While the Logistic model (R²=0.996 8) was the best when the extraction pressure was 20 MPa. The verification experimental result showed that the fitting degree range between the predicted values of the best models and the measured values were 0.936 4-0.986 0.[Conclusion] The effective diffusivity coefficient value of supercritical carbon dioxide extraction sterol from pine needles was enhanced concomitantly with increasing value of extraction pressure, while reduced with extraction time increased. The variety of free energy indicated that the mass transfer process of the supercritical carbon dioxide extraction sterol was a spontaneous process.

Key words: Korean pine needle, sterol, supercritical carbon dioxide, kinetics, thermodynamics