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Extraction extract

Shutdown rods Extracted Extracted Extracted Extracted... [Pg.232]

Extracted Extracted Extracted Recovery Extraction Extracted Recovery Extraction... [Pg.64]

The vegetable-tanning materials are commercially extracted using hot water. The extraction is normally done in countercurrent extractors that permit the final removal of the extracts with fresh water. The dilute extracts are then evaporated to the desired concentration in multiple effect evaporators. Some extracts may be further dried by spray drying or any other means that proves effective without overheating the extract. Extract preparation depends on the type of extract, the si2e of the operation, and the desired concentration of the final product. [Pg.86]

Solvent Extraction. Extraction processes, used for separating one substance from another, are commonly employed in the pharmaceutical and food processing industries. Oilseed extraction is the most widely used extraction process on the basis of tons processed. Extraction-grade hexane is the solvent used to extract soybeans, cottonseed, com, peanuts, and other oilseeds to produce edible oils and meal used for animal feed supplements. Tight specifications require a narrow distillation range to minimize solvent losses as well as an extremely low benzene content. The specification also has a composition requirement, which is very unusual for a hydrocarbon, where the different components of the solvent must be present within certain ranges (see Exthaction). [Pg.280]

Deviations from Raonlt s law in solution behavior have been attributed to many charac teristics such as molecular size and shape, but the strongest deviations appear to be due to hydrogen bonding and electron donor-acceptor interac tions. Robbins [Chem. Eng. Prog., 76(10), 58 (1980)] presented a table of these interactions. Table 15-4, that provides a qualitative guide to solvent selection for hqnid-hqnid extraction, extractive distillation, azeotropic distillation, or even solvent crystallization. The ac tivity coefficient in the liquid phase is common to all these separation processes. [Pg.1452]

An interesting application is the separation of cobalt and nickel neither Co(II) nor Ni(II) forms extractable chelates, but Co(III) chelate is extractable extraction is therefore possible following oxidation. [Pg.170]

Distribution ratio of Am(III) versus aqueous nitric acid cone, for carbamoylmethylphosphoryl type extractants, extractant cone. = 0.5 M. [Pg.433]

Lexical extraction extracting concepts from the text, using extensive lexicons referencing the various lexical forms a concept may take (e.g., synonyms, quasi-synonyms), each dictionary being triggered, controlled, or suppressed by contexts. [Pg.738]

Kujala, T., Loponen, J., and Pihlaja, K., Betalains and phenolics in red beetroot Beta vulgaris) peel extracts extraction and characterisation. Ztschr. Naturforsch. C/J. Biosci., 56, 343, 2001. [Pg.291]

Sam- ple Nr Kind of initial material for pectin extraction Extraction time min Yield of pectin, g per 200 g fresh material AUAC, % DE, % Molecul mass Mv Huggins constant Kh Intrinsic viscosity [ft] dl.g- Gel. strengtl TB... [Pg.943]

The procedure described earlier for sample preconcentration can be easily extended for the online extraction of solid samples, e.g., powdered plant materials. Horizontal conbguration of the chromatographic plate in the chamber facihtates this procedure, because the sample to be extracted is then placed on a carrier plate at the begiiming part of the adsorbent layer (or in the scrapped channel of the adsorbent layer), which should be directed upward [15,26]. The chamber is covered with a narrow plate, and the development is started with a snitable extracting solvent. In some cases, it is advantageous to put the narrow plate directly on the adsorbent layer to press the sample to be extracted. Extracted components are preconcentrated on the adsorbent layer at the end of the narrow plate, as shown in Fignre 6.26 [15]. [Pg.156]

Flavonoids may be extracted from fresh or frozen plant tissues or from herbarium material, although freeze-dried material may also be utilized [34]. It is very important to ensure that the matoial to be extracted is finely divided, whether by cutting or emshing, to ensure proper extraction. Extraction can be carried out successively with methanol containing some 10% of wate and thm with a 1 1 mixture of methanol and water. Each extraction should be carried out for a period of about 2 h, shaking or stirring to facilitate the process. The extracts are then combined for chromatographic separation. [Pg.338]

Drain the aqueous acetonitrile (lower) phase into a 500-mL round-bottom flask, and save the separatory funnel for extraction. Extract the hexane-fat mixture by transferring the mixture back to the polypropylene centrifuge bottle and adding 100 mL of acetonitrile-water (4 1, v/v) solution. Balance the duplicate centrifuge bottles, and cap and shake the bottles for 10 min on the shaker. Centrifuge the second extract at 11 000 rpm for 15 min. Decant this second extract into the 250-mL separatory funnel as before. After phase separation, combine the aqueous extracts in the 500-mL round-bottom flask, and discard the top hexane-fat layer. Add 10 drops of Dow Coming Antifoam B emulsion and 3 mL of 10% aqueous Igepal CO-660 (nonionic surfactant) to the flask. [Pg.356]

Most modern methods of analysis to determine pesticide residues in food commodities, whether a multi-residue method (MRM) or a single-residue method (SRM), can be broken down into three or four basic steps sample processing, sample extraction, extract cleanup (optional) and instrumental determination. [Pg.728]

Solvent extraction. Extraction of neonicotinoid insecticides from water is a simple process involving saturation with sodium chloride and extraction with diethyl ether, dichloromethane or ethyl acetate. This extraction procedure will allow the simultaneous extraction of all neonicotinoids. [Pg.1142]

Extraction. Extract 20 g of sample as described for fruit and vegetables. Evaporate the acetone extract to dryness by rotary evaporation under reduced pressure in a <40 °C water-bath. [Pg.1345]

Solvent Extraction Aqueous sample is partitioned with an immiscible organic solvent. Extraction efficiency depends on the affinity of the solute for the organic solvent. All sample types Samples with a high affinity for water are not extracted. Extractions can be performed by a simple single equilibration or by multiple equilibrations with fresh solvent. Solvent impurities concentrated along with sample. [Pg.376]

Bioassay of Extracts. Extracts tested for the presence of cyclohexi-mide were also bioassayed for phytotoxicity. The extracts were redis-sOlved in acetone, and 0.2 mg in 2 pi was applied to 6-cm-dia disks of filter paper. The extract was distributed on the paper with 0.2 ml of methanol. The disks were dried with warm air, placed in 1.5 x 6 cm petri dishes, and moistened with 1.5 ml distilled water. Ten cress seeds were placed on the paper, and after incubation for 3 d at 28 C radicle length of the seedlings was measured. [Pg.342]

Rodriguez de Sotillo D, Hadley M, Holm ET. 1994. Phenolic in aqueous potato peel extract extraction, identification and degradation. J Food Sci 59 649-651. [Pg.47]

These can be the natural material itself one example would be pieces of vanilla pod or an extract, e.g. vanilla extract. Extracts can be prepared in several ways. One is to distil or to steam distil the material of interest. Another is to extract the raw material with a solvent, e.g. ethyl alcohol. Alternatively, some materials are extracted by coating the leaves of a plant with cocoa butter and allowing the material of interest to migrate into the cocoa butter. These techniques are also used in preparing perfumery ingredients, indeed materials like orange oil are used in both flavours and perfumes. [Pg.99]

K Soil extracts Extract with Na-tetra-phenylboron to eliminate interferences 166)... [Pg.99]

Efficiency of Extraction. Selectivity of Extraction. Extraction Systems. Extraction of Uncharged Metal Chelates. Methods of Extraction. Applications of Solvent Extraction. [Pg.6]

In order to understand the removal of FMs during wastewater treatment, it is necessary to measure these compounds throughout the wastewater treatment process. Because of the complex nature of wastewater matrices and the low concentration of FMs (0.001-60 pg/L) [11] throughout the treatment plant, accurate and sensitive analytical methods have been developed by a number of researchers. Fortunately, the analytical techniques developed to measure traditional SOCs, such as solvent extraction, extract concentration, and analysis by gas chromatography-mass spectrometry, in general also apply to FMs. [Pg.84]

Lipinski, J. (2001) Automated solid phase dynamic extraction-Extraction of organics using a wall coated syringe needle. Fresenius J. Anal. Chem. 369, 57-62. [Pg.35]


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See also in sourсe #XX -- [ Pg.153 , Pg.154 ]




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