超临界CO2萃取蛋黄粉中甘油三酯和胆固醇的影响因素研究

以蛋黄粉为原料,研究用超临界ＣＯ２萃取技术脱除其中的甘油三酯和胆固醇的操作条件,得到了萃取压力、萃取时间ＣＯ２流量等因素对脱除率的影响。在２４ＭＰａ、５ｈ、５０℃的条件下,某油三酯和胆固醇的脱除率可达８０％以上。     

超临界二氧化碳萃取蛋黄油实验研究

介绍了超临界二氧化碳萃取技术提取蛋黄洫的工作原理及工艺流程。设计了正交实验.考察萃取压力、萃取温度、萃取时间等参数对萃取率的影响,确定了最佳工艺条件。     

超临界二氧化碳萃取蛋黄油的研究

采用超临界萃取方法,以二氧化碳作为溶剂,在比较温和的实验条件下,从蛋黄粉中萃取蛋黄油。实验条件为：温度３５℃～７５℃,压力２５ＭＰａ～３６ＭＰａ,ＣＯ２的流量约７．０ｋｇ／ｈ。实验得到最佳的萃取条件为：５５℃、２８ＭＰａ～３６ＭＰａ。气相色谱分析结果表明：在不同的萃取阶段蛋黄油的组成类似。并且得到了不同实验条件下蛋黄油在超临界二氧化碳中的溶解度     

超临界二氧化碳萃取蛋黄油实验研究

介绍超临界二氧化碳萃取技术提取蛋黄油的工作原理及工艺流程.设计了正交实验,考察了萃取压力、萃取温度、萃取时间等参数对萃取率的影响,确定了最佧工艺条件.     

蛋黄卵磷脂制备工艺及超临界CO_2脱蛋黄油实验研究

对用超临界CO_2萃取技术制备蛋黄卵磷脂的几种典型工艺进行了归纳、分析和比较。根据选择的工艺,对关键设备萃取器料筒进行了改进,通过正交试验,探讨了萃取压力、温度、时间、料筒层数等条件对蛋黄油脱除率的影响规律。     

超临界CO2萃取回收SBA-15中的有机模板剂

在200 mL高压萃取釜内,对含夹带剂的超临界CO2萃取回收SBA-15中有机模板剂P123(EO20PO70EO20)的最佳工艺条件进行了研究,考察了夹带剂种类、萃取温度、萃取压力、夹带剂流量对回收率的影响,确定最佳萃取工艺条件为：甲醇作夹带剂,温度45℃,压力27 MPa,夹带剂流量4 mL/min,萃取时间1.5 h,在此条件下P123回收率可达73.7%. 对不同方法脱除P123后的SBA-15进行了表征,结果表明,含甲醇夹带剂的超临界CO2萃取法是一种高效环保的方法,且得到的SBA-15保留了很好的骨架有序性,不会造成骨架硅羟基脱除,克服了高温焙烧脱除模板剂造成的孔道收缩问题.     

Oil Production from De-shelled Aquilaria crassna Seeds Using Supercritical Carbon Dioxide Extraction

This study examined the use of supercritical carbon dioxide (SC-CO₂) in the extraction of triglycerides from de-shelled Aquilaria crassna seeds. A central composite response surface methodology was employed to evaluate the effects of pressure, temperature and solvent-to-solid ratio (SSR) on total yield (TY), concentration of triglycerides (C _TG) and recovery of triglycerides (R _TG). For this experimental design, pressures that ranged from 250 to 350 bar, temperatures that ranged from 313 to 333 K and SSR that ranged from 80 to 120 were investigated for the SC-CO₂ extractions of 15 g of powdered de-shelled A. crassna seeds at a CO₂ flow rate of 25 mL/min under the supercritical phase. The values of TY, C _TG and R _TG achieved were 36.89 %, 709.5 mg/g and 95.4 %, respectively, under the conditions of a pressure of 340 bar, a temperature of 333 K and an SSR of 115 obtained from the quadratic fitting models.     

Fractionation of Gluten Lipids with Supercritical Carbon Dioxide

Gluten lipids are of two kinds, polar and nonpolar. Both groups consist of a large number of lipids. Gluten lipids can be extracted by conventional solvents as ethanol but also by supercritical carbon dioxide. The high density and the good mass transport properties make the supercritical fluid an excellent solvent. Ethanol extracted gluten lipids have been fractionated with supercritical CO₂ at different pressures and constant temperature. The extract contains triglycerides and free fatty acids, and a more concentrated fraction of polar lipids is left in the extraction vessel. While both polar and nonpolar lipids are soluble in ethanol, only nonpolar lipids are dissolved by supercritical CO₂. An addition of a small amount of ethanol to the CO₂, can, however, increase the solubility of the polar lipids.     

Extraction of Phospholipids from Egg Yolk Flakes Using Aqueous Alcohols

Two alcohols, ethanol and butanol, with different water contents were evaluated for phospholipids (PL) sequential extraction from drum dried egg yolk flakes. It showed that butanol was more effective in extracting total yolk lipids compared to ethanol, but the PL in the extract had the same concentration as in the original yolk total lipid. The use of aqueous ethanol of 95 and 75% resulted in lipid extracts with higher PL concentration during the initial stages of the sequential extraction. When ethanol was further diluted to a concentration of 55%, the solvent lost its PL extraction ability, and the total lipid recovery also decreased dramatically. When both the PL purity and recovery were considered, 75% ethanol was the most effective aqueous alcohol for PL extraction and enrichment from the yolk flakes. In the first stage of extraction using such a solvent, 67% of the total PL in the original yolk was recovered in a lipid fraction with a PL purity of 75%. This study identified the optimal ethanol concentration for PL extraction from dried egg yolk. With this information, the best solid:solvent ratio can be designed to extract and enrich the polar lipids from lipid-bearing materials with known moisture content using a renewable or “green” solvent, ethanol.     

超临界CO2萃取烟草中茄尼醇

研究了萃取时间、解析温度、萃取压力等因素对超临界CO2萃取烟草中茄尼醇萃取率的影响。结合皂化等预处理措施,并通过正交实验得到了提取茄尼醇的最佳工艺条件,即以体积分数90%的乙醇为夹带剂,在萃取压力为35 MPa、萃取温度为50℃、解析温度为40℃时,萃取3 h后,产品茄尼醇质量分数为40.14%,萃取率达到98.53%。     

超临界二氧化碳萃取技术

超临界流体萃取(Supercritical Fluid Extraction)技术是一种新型的化工分离技术.本文综述了超临界流体萃取技术的发展.超临界流体的特性,介绍了超临界二氧化碳萃取技术在中草药,食品工业,香料工业和环保技术方面的应用,并对超临界二氧化碳萃取技术的现状和前景进行了分析.     

超临界二氧化碳流体萃取分离技术

超临界流体的扩散系数比一般液体的扩散系数高一个数量级,而粘度要低一个数量级。与液-液萃取系统相比,超临界流体萃取系统具有较快的传质和萃取速度,因此能有效地对固体样品进行萃取分离。常用的超临界流体有乙烯、氙气、一氯三氟乙烷、二氧化碳、乙烷、一氧化二氮、一氟甲烷、丙烷、氨等,应用领域也从早期的天然香料提取扩展到食品、环境保护、农药、烟草、中药等行业,超临界萃取技术越来越受到国际科技届的广泛关注。但该技术应用于工业化生产尚需一定时日,还需要进一步降低操作成本和设备的造价。     

Elution of Gold from Activated Carbon Using Supercritical Carbon Dioxide

Abstract

A novel method for the desorption of gold from activated charcoal is reported. Ion pair solvation of sodium dicyanoaurate (I) (Na⁺ … Au(CN)₂ ^? by tributyl-phosphate facilitates the charge neutralization necessary for the elution of the ionic Au(CN)₂ ^? by the non-polar supercritical carbon dioxide. The method is sensitive to pressure and temperature, and the static (no CO₂ flow) period is more significant than the dynamic (CO² flow) period. The presence of water is necessary to effect extraction.     

Equilibrium and Rate Data for the Extraction of Lipids Using Compressed Carbon Dioxide

Abstract

Equilibrium data are given for the solubilities in compressed C0₂ of the lipid components in freshly ground rape seed and of glycerol trioleate (a typical constituent of rape oil) at pressures up to 200 bar and temperatures 25 to 75C. Continuous flow tests in which a bed of ground rape seed was contacted with a stream of liquid CO₂ at 25C and varied flow conditions are also reported. The results are collated in terms of an empirical mass transfer coefficient. A sharp change took place in the lipid concentration in the extractant stream leaving the bed when about 65% of the available oil had been extracted. This, and changes in the composition of the extract, are discussed, together with the use of this type of data for design purposes.     

二氧化碳超临界萃取法提取核桃中油酸研究

利用二氧化碳超临界萃取法(Supercritical Fluid Extraction,简称SFE)对陇东核桃中的脂肪酸进行了提取研究,并采用气相色谱-质谱联用仪(GC-MS)对所得的脂肪酸组成进行了分析,实验结果表明:萃取压力20 MPa、温度40℃、CO_2泵频率20 L/h,萃取时间4 h时核桃油酸的萃取率高,无杂质残留,感官效果好。     

超临界CO2提取金银花浸膏

本文用超临界ＣＯ２技术从干燥保存的金银花中提取挥发性香料成分。结果表明,用超临界ＣＯ２提取的金银花浸膏具接近原料的特征清香,提取率高;提取挥发油后的金银花仍可作为提取氯原酸的药材。     

The Effects of Biopolymer Encapsulation on Total Lipids and Cholesterol in Egg Yolk during in Vitro Human Digestion

The purpose of this study was to examine the effect of biopolymer encapsulation on the digestion of total lipids and cholesterol in egg yolk using an in vitro human digestion model. Egg yolks were encapsulated with 1% cellulose, pectin, or chitosan. The samples were then passed through an in vitro human digestion model that simulated the composition of mouth saliva, stomach acid, and the intestinal juice of the small intestine by using a dialysis tubing system. The change in digestion of total lipids was monitored by confocal fluorescence microscopy. The digestion rate of total lipids and cholesterol in all egg yolk samples dramatically increased after in vitro human digestion. The digestion rate of total lipids and cholesterol in egg yolks encapsulated with chitosan or pectin was reduced compared to the digestion rate of total lipids and cholesterol in other egg yolk samples. Egg yolks encapsulated with pectin or chitosan had lower free fatty acid content, and lipid oxidation values than samples without biopolymer encapsulation. Moreover, the lipase activity decreased, after in vitro digestion, in egg yolks encapsulated with biopolymers. These results improve our understanding of the effects of digestion on total lipids and cholesterol in egg yolk within the gastrointestinal tract.     

CO2超临界萃取叶黄素工艺条件的优化控制

采用超临界CO2提取方法探讨了从万寿菊中提取叶黄素的最佳工艺条件.通过单因素和正交实验确定影响叶黄素萃取的因素为:时间>温度>压力>CO2流量;优化工艺条件为:萃取时间3h,萃取压力25MPa,温度55℃,CO2流量10L·h-1,分离罐Ⅰ温度42℃,压力11MPa,分离罐Ⅱ温度38℃,压力同储罐.在该优化工艺条件下,...     

Supercritical Carbon Dioxide Extraction of Uranium from Acidic Medium Employing Calixarenes

Various calixarenes were evaluated for the supercritical fluid extraction of uranium from nitric acid medium. The extraction efficiency was found to be affected by various parameters, namely pressure, temperature, CO₂ flowrate, extraction time, and molarity of nitric acid. The addition of HPFOA (pentadecafluoro-n-octanoic acid) for the production of CO₂-phillic fluorinated counter ion enhanced the extraction efficiency. Under optimized conditions (pressure of 200 atm, temperature of 323 K, 30 minutes of static time followed by 30 minutes of dynamic time, CO₂ flowrate of 2 mL min^?1, nitric acid molarity of 0.1 M) for uranium: calixarene: HPFOA mole ratio of 1:5:10, highest extraction efficiency could be obtained with p-tert.-butyl calix[6]arene (79.9%). Solvent extraction study with hexane as the organic phase indicated the formation of [UO₂ (calixarene)]²⁺. In order to assess the suitability of the developed method to extract uranium in the presence of a host of other ions, extraction efficiency for other metal ions was estimated.