共查询到20条相似文献,搜索用时 0 毫秒
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Willam E. Artz Robert M. Sauer Jr. 《Journal of the American Oil Chemists' Society》1992,69(4):309-313
An improved supercritical fluid micro-extraction cell of increased reliability was designed for on-line supercritical fluid
extraction and chromatography (SFE/SFC) of food and other lipid-related samples. The key components in the modified cell include
a Swagelok stainless steel reducing union with a dual ferrule as the cell, with polyetherether-ketone (PEEK) ferrules and
nuts to connect the cell to the control valve. The new cell did not leak under all conditions examined (100–500 atmospheres,
40–80°C), even after numerous extractions (>250). The quantitative performance of the cell was evaluated with fatty acid standard
solutions, technical grade fatty acid sources and wheat flour. The percent relative error (%RE) for the fatty acid standards
and technical-grade fatty acid samples was ≤6.0% for oleic, linoleic and linolenic acid. The %RE for oleic and linoleic acid
in the whole-wheat samples was ≤10%. The results demonstrate that the new extraction cell can be used for quantitative extractions
and that the sensitivity of the SFE/SFC technique is excellent. Similar SFE/SFC methods could prove useful in studying the
interaction of free fatty acids with various food components such as enzymes, amylose and proteins. 相似文献
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Carmen Soto Enma Conde Andrés Moure María Elvira Zúñiga Herminia Domínguez 《European Journal of Lipid Science and Technology》2008,110(11):1035-1044
This paper describes the extraction of borage seed oil by supercritical carbon dioxide (SC-CO2) and the further extraction of antioxidants from the SC-CO2-defatted borage meal with organic solvents (water, methanol, ethanol and ethyl acetate). The optimal conditions for oil extraction were obtained at 303 and 323 K at 200 bar, 2.5 h and a continuous flow of CO2 of 1.5 L/h introduced through the bottom when the operating pressure and temperature were reached, attaining a yield of 60%. Borage oil is rich in unsaturated fatty acids; oleic acid, linoleic acid and linolenic acid accounted for 74% of the total fatty acid content under the above conditions. The highest extraction yield was achieved using water or methanol as extracting solvent from the SC-CO2-defatted borage meal at 303 K and pressures of 200 and 150 bar for water and methanol, respectively. The most potent extracts, according to all methods tested, were obtained with water and methanol. 相似文献
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超临界CO2萃取技术及其在天然产物提取中的应用 总被引:2,自引:0,他引:2
超临界流体萃取技术是一种新型的分离技术,由于它具有高效、方便、安全、环保、选择性好等优点,使得这项技术在天然产物活性成分的提取上得到迅速发展,应用范围和种类也不断扩大。介绍了超临界CO2萃取的原理、特点、影响因素及其在天然产物研究中的应用,并对其发展前景做了展望。 相似文献
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超临界流体与膜过程的耦合技术 总被引:1,自引:1,他引:1
介绍了超临界流体与膜过程的耦合技术的研究进展和最新研究成果。将超临界CO_2萃取与纳滤过程相耦合,可以不经历压力、温度和相变循环而使CO_2循环利用,从而降低过程能耗、减小操作费用。将纳滤过程与超临界CO_2萃取相耦合,可以对萃取收率和选择性独立调控,使它们分别达到最佳值,从而实现对萃取物在高收率条件下达到精细分离的目的。将超临界CO_2引入高粘性液体的超滤过程,会在不提高温度和无需引入化学剂的情况下,大大降低流体粘度、增大透过流率、提高过滤效率、减小过程能耗,同时也有利于环境保护、提高产品质量。 相似文献
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干姜的超临界萃取及其萃取物在卷烟中的应用 总被引:3,自引:0,他引:3
为了开发新型烟用香原料,用超临界萃取和水蒸气蒸馏的方法提取干姜萃取物,优化了超临界萃取工艺,用GC/MS法分析了萃取物中的主要成分,并将萃取物用于卷烟中。结果表明:①干姜超临界萃取的最佳工艺是,萃取压力30MPa,萃取温度55℃,萃取时间2h,CO2流量为2.5L/min,分离压力8MPa,分离温度45℃,在该工艺条件下萃取物得率为2.48%;②两种提取方法得到的萃取物有十八种共有成分,主要是姜烯、醛、酯类等,超临界萃取物成分更多,生姜特征香气更浓;③超临界萃取物应用于卷烟,具有改善香气质和香气量、丰富烟香、改善口感的作用,效果明显比水蒸气蒸馏萃取物好,更适合用作烟用香料。 相似文献
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简单介绍了超临界流体的特性 ,着重对国内外超临界技术在化学工业中的应用状况进行了综述 ,并指出了超临界技术的发展方向。 相似文献
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超临界技术在石油化工领域的应用 总被引:4,自引:0,他引:4
介绍了超临界流体的特性,重点论述了超临界化学反应、超临界萃取技术、超临界水氧化技术、超临界流体结晶技术等在石油化工领域的化学反应、炼油工业、环境保护、材料制备等方面的应用状况,并指出了超临界技术的发展方向。 相似文献
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《分离科学与技术》2012,47(18):2741-2760
The main objective of this review is to approach and highlight the main applications of Supercritical Fluid Extraction (SFE) through the search in scientific papers and patents. The principles of the technique and the identification of the main works developed in different areas, such as food science, pharmaceuticals, chemical residues, biofuel, and polymers are presented. Additionally, it presents the new and innovative combined methods where SFE has been used, as well as the perspectives of this technology and the profile of countries that own the rights for the use of SFE through patent registration. In this review a compilation of the data extracted from 196 different scientific article and 594 patent documents, from a universe of 2.314 documents was done, showing the improvement of the technique in the last years. 相似文献
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超临界流体萃取开辟了分馏过程的新领域,是一种新型的分离技术。主要介绍了超临界流体萃取的基本原理、典型流程、特点及其在化工过程中的应用。 相似文献
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超临界二氧化碳流体提取咖啡因研究进展 总被引:2,自引:0,他引:2
介绍了超临界流体萃取技术,综述了超临界二氧化碳流体提取咖啡因研究进展,并对其中的一些具有代表性的工艺进行了详细的阐述和评价。 相似文献