SFE-CO2Molecular Distillation Technique In Separation And Purification Of α-Linolenic Acid In Flaxseed Oil

Flax.(Linum usilalissimiim L) is an annual herb, which likes low temperature and dry climate. It is a long-day crop and widely distributed around the world with5.000years of cultivation history. The study is aimed at extracting oil from flax by Supercritical fluid extraction (SFE) and the molecular distillation(MD).The constituents of distilled oil are analyzed by gas chromatography-mass chromatography. Effects of different extraction conditions on product yield and quality of extracted oil samples are discussed and optimum technology variables are obtained. Thus, theoretical foundations for comprehensive utilization of flax are provided.Supercritical fluid extraction (supercritical Fluid Extraction) SFE is a modern separation technology, supercritical fluid as a solvent. SFE has a low processing temperature, the effect of extraction of volatile components, oxidative deterioration does not occur compared to the advantages with the conventional method can be used to pigment, fragrance, flavor, grease extraction. The conclusions of this experimental study concluded that supercritical CO2extraction of the main factors of flax seed oil extraction pressure. Extraction temperature, extraction time, CO2flow rate had no significant effects on the experimental results. Orthogonal extraction conditions:the CO2flows25L/h; extraction pressure30MPa; extraction temperature of45degrees Celsius; extraction time2h. Operation, under the extraction conditions in the preferred flax seed oil extraction rate basically stable, the average extraction rate of36.70%. The resulting flax seed oil golden yellow, transparent. Supercritical CO:high extraction flax seed oil extraction rate, the resulting product is more pure and will not cause contamination of the product. Therefore, to avoid the problem of residual solvent and environmental pollution.Molecular distillation (Molecular Distillation), also known as a short-path distillation, a high vacuum conditions, far below the boiling point of liquid-liquid separation process, completed by the characteristics of the type of the molecular free path. Particularly applicable to high boiling point, separation of the heat-sensitive material, the molecular distillation is carried out under high vacuum (1Pa), and the distillate heating time is very short, so as to ensure a higher boiling point and hot oxygen-sensitive organic matter will not be oxidized during distillation, polymerization, decomposition been destroyed. Wiped film molecular distillation equipment of application VKL70type small scale purification test for alpha-linolenic acid, low temperature distillation, the product is easy to produce the decomposition deterioration. And easy to operate, high separation efficiency, easy to achieve industrialization. Wiped film molecular distillation equipment of application VKL70type small scale purification test for alpha-linolenic acid, low temperature distillation, the product is easy to produce the decomposition deterioration. And easy to operate, high separation efficiency, easy to achieve industrialization. Test uses a multi-stage operation, appropriate separation:distillation temperature of90°C to105°C; the operating pressure0.3Pa to1.8Pa; feed temperature of60°C; feed rate of90ml/h to100mL/h; membrane wiper speed150r/min. After four molecular distillation, the raw material of alpha-linolenic acid from67.5%purified to82.3%.