【摘要】 以二氯甲烷为溶剂,超临界CO2为抗溶剂,采用超临界流体强制分散溶液技术成功地对天然胡萝卜素进行了超细化.采用SEM照片分析微粒形貌,利用粒度分析仪测定微粒粒径.实验考察了压力、溶液浓度与流量及CO2流量对产品粒度的影响;用液体射流破碎、超临界CO2作用下的溶液体积膨胀、膨胀溶液的过饱和度及沉淀粒子团聚等解释了产品粒度随操作条件的变化规律.在实验范围内制得了平均粒径为0.6~5μm且粒度分布窄的不定形胡萝卜素微粒.微粒粒径随压力、CO2流量及溶液流量增大而减小,随溶液浓度增大而先减小后增大.更多还原

【Abstract】 Natural carotene has been successfully micronized from dichloromethane solutions using CO₂ as antisolvent by the particle formation method of Solution Enhanced Dispersion by Supercritical Fluids（SEDS）.The aim is to study the influence of operating variables（concentration,pressure,solution flow rate and CO₂ flow rate） on final sizes of the particles micronized.The temperature,pressure,carotene solution flow rate,CO₂ flow rate and solute concentration in experiments were 313K,8—22MPa,1—3.5mL·min^-1,0.2—180L·min^-1 and 1—7g·L^-1 respectively.The morphologies of microparticles were examined by SEM.Particle-Size（PS） analyses were performed using N4-Plus Coulter.Within the experiments performed,amorphous micro-sized particles with PS of 0.6～5μm and a narrow size distribution were obtained.The mechanisms that control particle size were explained in terms of the jet breakup,solution volumetric expansion,and the relative relevance of the supersaturation of the expanded solution and the agglomeration of micronized particles.Studies indicate that PS of micronized carotene decreases with the increase of pressure,CO₂ flow rate and solution flow rate;decreases at the beginning and then increases with solution concentration.更多还原