Distillation solvent extraction

Essential Oils. Volatile oils from plants are referred to as essential oils. The oils can be obtained through steam distillation, solvent extraction, or separation of the oils from pressed fmit. They consist of oxygenated compounds, terpenes, and sesquiterpenes. The primary flavor components of essential oils are oxygenated compounds. Terpenes contain some flavors but are often removed from the essential oil because they are easily oxidized (causiag off-flavors or odors) and are iasoluble. Essential oils are prepared from fmits, herbs, roots, and spices. 

Extracts (petroleum), heavy naphthenic distillate solvent Extracts (petroleum), heavy paraffinic distillate solvent Extracts (petroleum), light naphthenic distillate solvent Extracts (petroleum), light paraffinic distillate solvent Extracts (petroleum), light vacuum gas oil solvent Euel oil no. 6... 

In liquid-solid extraction (LSE) the analyte is extracted from the solid by a liquid, which is separated by filtration. Numerous extraction processes, representing various types and levels of energy, have been described steam distillation, simultaneous steam distillation-solvent extraction (SDE), passive hot solvent extraction, forced-flow leaching, (automated) Soxh-let extraction, shake-flask method, mechanically agitated reflux extraction, ultrasound-assisted extraction, y -ray-assisted extraction, microwave-assisted extraction (MAE), microwave-enhanced extraction (Soxwave ), microwave-assisted process (MAP ), gas-phase MAE, enhanced fluidity extraction, hot (subcritical) water extraction, supercritical fluid extraction (SFE), supercritical assisted liquid extraction, pressurised hot water extraction, enhanced solvent extraction (ESE ), solu-tion/precipitation, etc. The most successful systems are described in Sections 3.3.3-3.4.6. Other, less frequently... 

Applications Simultaneous steam distillation-solvent extraction has been in use for many years [163]. Steam distillation combined with continuous liquid extraction is an efficient technique for the removal and isolation of volatile compounds in various matrices (environmental,... 

Glausch, A., Blanch, G.P., Schurig, V. (1996). Enantioselective analysis of chiral polychlorinated biphenyls in sediment samples by multidimensional gas chromatography-electron-capture detection after steam distillation-solvent extraction and sulfur removal. J. Chromatogr. A 723, 399 104. 

Richard, J. J., and Junk, G. A., Steam Distillation, Solvent Extraction, and Ion Exchange for Determining Polar Organics in Shale Process Waters. Anal. Chem, 1984. 56 pp. 1625-1628. 

Ahel et al. [11] used steam distillation/solvent extraction and determination by normal phase HPLC for the analysis of NP, NPEOi and NPE02 in freshwater fish. 

Seidel V, Lindner W. 1993. Universal sample enrichment technique for organochlorine pesticides in environmental and biological samples using a redesigned simultaneous steam distillation-solvent extraction apparatus. Anal Cem 65 3677-3683. 

Separation processes separate cmde oil into some of its fractions. Fractional distillation, solvent extraction, and crystallization are some of the major separation processes. 

I Isolation Crystallization Distillation Solvent extraction Sublimation... 

Other odoriferous materials are derived from the leaves and young twigs of Cistus ladaniferus. Cistus oil is obtained by steam distillation solvent extraction yields cistus concrete. Cistus oil, in contrast to labdanum oil, consists mainly of monoterpene hydrocarbons. 

Essences of pink and white fresh guava obtained by direct extraction of flesh juices with dichloromethane revealed that the total amount of Cs aldehydes, alcohols, and acids comprised 20 and 44% of the essence of fresh white and pink guavas, respectively [49]. The flavour of the Costa Rican guava has been described as sweet with strong fruity, woody-spicy, and floral notes [53]. One hundred and seventy-three volatile compounds were isolated by simultaneous steam distillation-solvent extraction. The terpenes and terpenic derivatives were found in this fruit in major concentrations and were strong contributors to tropical fruit notes (Fig. 8.1). The aliphatic esters contributed much to its typical flavour. 

Volatile compounds isolated from strawberry guava fruit by simultaneous steam distillation-solvent extraction were identified by capillary gas chromatography-mass spectrometry (GC-MS) and were characterised sensorially by sniffing GC [52]. Terpenes and terpenic derivatives were identified and were shown to contribute much to the typical strawberry guava flavour. The presence of many aliphatic esters and terpenic compounds is thought to contribute to the unique flavour of the strawberry guava fruit. 

Another investigation reported the esters as the predominant volatile components of the Maradol variety (about 41% w/w of the total volatiles) [51]. The major representative compounds in the simultaneous steam distillation-solvent extraction were methyl butanoate and ethyl butanoate. Previous work described the esters as the predominant compounds among the volatiles papayas, for example, from Sri Lanka and Colombia had 52 and 63% of esters in the total volatiles respectively [25,41]. 

Polychlorobiphenyls were recovered from sediments in another investigation by steam distillation/solvent extraction, followed by enantioselective analysis using multidimensional electron capture gas chromatography [189]. 

Frenock, sodium-2,2,3,3-tetrafluoroproprionate Steam distillation, solvent extraction Mass fragmentography of l-benzyl-3-p-polytriazine derivative [477]... 

Carboxylic -acids, nitriles, aldehydes, ketones Steam - distillation, solvent extraction, ion exchange chromatography, GC [677]... 

Reaction of an aqueous solution of cystine with thiamin, glutamate, and ascorbic acid produces a complex mixture of compounds with an overall flavor resembling that of roasted meat. The reaction was carried out at 120 C for 0.5h at pH 5.0 in a closed system. The aroma compounds were isolated by means of the simultaneous steam distillation/solvent extraction method. The flavor concentrate was pre-separated by liquid chromatography on silica gel and subsequently analysed by GC and GC/MS. Unknown flavor components were... 

Both processes involve the addition of a new material, the solvent, to the mixture. The solvent is chosen so as to increase the relative volatility of the components to be separated. During extractive distillation, the solvent is generally added near the top of the column, and because it has a low volatility it is withdrawn with the product at the bottom. In azeotropic distillation, the solvent is withdrawn as an azeotrope with one or more of the components to be separated—usually in the overhead product. If the ratio of the components to be separated is different in the withdrawn azeotrope from their ratio in the feed to the column, then at least a partial separation has been achieved. In both processes it is necessary to separate the solvent from the product. This can be accomplished, for example, by distillation, solvent extraction, or even gravity settling, depending on the characteristics of the components involved. 

Jayatilake, A., Poole, S.K., Poole, C.F. and Chichila, T.M.P. (1995) Simultaneous microsteam distillation -solvent-extraction for the isolation of semivolatile flavour compounds from Cinnamomum and their separation by series coupled-column gas chromatography. Analytica Chimica Acta 30, 147-162. 

This monograph Is arranged In three main sections. A short section (i) describes general procedures used to prepare samples for rapid radiochemical separation. Then the separations reported In the literature have been categorized In two different ways. In section II the procedures have been arranged by type of process, such as recoil, distillation, solvent extraction, etc. In each subsection there are given typical examples of different kinds of techniques reported — but the sections are not necessarily exhaustive. 

Although the detailed methods which have been developed for separating short-lived radioisotopes are extremely varied and depend on the particular problem at hand, all are based on a relatively few general types of separation processes such as recoil, distillation, solvent extraction, precipitation,... 

SYNS EXTRACTS (PETROLEUM), HEAVY NAPHTHENIC DISTILLATE SOLVENT (9CI) HEAVY NAPHTHENIC DISTILLATE SOLVENT EXTRACT... 

HEAW NAPHTHENIC DISTILLATE see MQV780 HEAW NAPHTHENIC DISTILLATE. SOLVENT EXTRACT see MQV857... 

Radiochemical purification of the induced activity in the presence of carrier involves chemical operations such as precipitation, distillation, solvent extraction, chromatography, and ion exchange. While the chemistry performed on the carrier and sample should be designed to isolate the material in a pure state, a useful operation frequently carried out is scavenging. Strongly adsorptive precipitates such as ferric hydroxide, lanthanum fluoride, and antimony sulfide may be formed in the solution. These precipitates, by coprecipitation, occlusion, and surface adsorption can be used to remove unwanted traces of activity. A scavenging agent should be chosen that wdll not carry down appreciable amounts of the carrier from solution. An alternative method is to add hold-back carriers for the unwanted traces of activity and precipitate the required element in their presence. 

J. J. Richaid, G. A. Junk, Steam Distillation, Solvent Extraction,and Ion Exchange forDetermin ing PolarOiganics in Shale Process Wateis, Anal.Chem. 19S4, i6, 1625-1628. 

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