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Combined infrared drying

B. Hydrogenolysis of the Phenolic Ether Biphenyl. To a solution of 10 g. (0.032 mole) of the product from Part A in 200 ml. of benzene is added 2 g. of 5% palladium-on-charcoal, and the mixture is shaken with hydrogen in a Parr apparatus at 40 p.s.i. and 35-40° for 8 hours (Note 3). The mixture is filtered, and the insoluble residue is washed with three 100-ml. portions of hot ethanol (Note 4). The filtrates are combined, and the solvent is removed by means of a rotary evaporator at 60° (12 mm.) to leave a solid residue. The product is dissolved in 100 ml. of benzene, and 100 ml. of 10% sodium hydroxide solution is added. The mixture is shaken, and the layers are separated. The aqueous layer is extracted with 100 ml. of benzene, and the original benzene layer is washed with 100 ml. of water (Note 5). The benzene solutions are combined and dried over magnesium sulfate. Removal of the benzene by distillation yields 4.0-4.7 g. (82-96%) of biphenyl as a white powder, m.p. 68-70° (Note 6). The infrared spectrum is identical with that of an authentic sample, and a purity of at least 99.5% was indicated by gas chromatography analysis. [Pg.126]

Haghi, A.K. and H. Ghanadzadeh, 2006. Experimental study on combined infrared and microwave drying of porous media with particular apphcation in wood industry. International Journal of Applied Mechanics and Engineering, 11(4), 985-991. [Pg.418]

Infrared Drying Combined with other Types of Drying... [Pg.374]

Jaturonglumlert, S., Kiatsiriroat, T, 2010. Heat and mass transfer in combined convective and far-infrared drying of fruit leather. /. Food Eng. 100(2) 254-260. [Pg.383]

H. Tai and A. L. Underwood, Infrared Spectrophotometry of Sulfate Ion. Combining Freeze-Drying with Potassium Bromide Disk Technique, Anal. Chem. 29, 1430, 1957. [Pg.422]

A mixture consisting of 0.69 g (10.5 mmoles) of zinc-copper couple, 12 ml of dry ether, and a small crystal of iodine, is stirred with a magnetic stirrer and 2.34 g (0.7 ml, 8.75 mmoles) of methylene iodide is added. The mixture is warmed with an infrared lamp to initiate the reaction which is allowed to proceed for 30 min in a water bath at 35°. A solution of 0.97 g (2.5 mmoles) of cholest-4-en-3/ -ol in 7 ml of dry ether is added over a period of 20 min, and the mixture is stirred for an additional hr at 40°. The reaction mixture is cooled with an ice bath and diluted with a saturated solution of magnesium chloride. The supernatant is decanted from the precipitate, and the precipitate is washed twice with ether. The combined ether extracts are washed with saturated sodium chloride solution and dried over anhydrous sodium sulfate. The solvent is removed under reduced pressure and the residue is chromatographed immediately on 50 g of alumina (activity III). Elution with benzene gives 0.62 g (62%) of crystalline 4/5,5/5-methylene-5 -cholestan-3/5-ol. Recrystallization from acetone gives material of mp 94-95° Hd -10°. [Pg.112]

Propanone, l-chloro-l,l,3,3,3-pentafluoro-] (b.p. 7.8° available from PCR, Inc. or Allied Chemical Corp.) are combined in a flask fitted with a dry ice condenser and a magnetic stirring bar. The refluxing mixture is stirred for 4-0 hours and then allowed to warm gradually to room temperature. The contents of the flask are extracted three times with anhydrous ether, and the combined extracts are distilled at atmospheric pressure. After the ether has been removed, continued distillation gives 22.8-28.5 g. (55-69%) of l,l,l-trichloro-3,3,3-trifluoroacetone, b.p. 83.5-84.5°, infrared (film) 1790 cm. - This compound is stored at room temperature in a tightly stoppered bottle. In the absence of reliable toxicity data, it should be handled with normal precautions. [Pg.124]

This method has been applied to bottom sediments and muds [4]. The mud sample is centrifuged to separate the water, dried at room temperature, ground and sieved. This residue is extracted for lh at 80°C with methanol-benzene (1 1), the extraction is repeated twice, and the combined extracts are evaporated and the residue dissolved in water. Alkylbenzenesulphonates are then determined by infrared spectroscopy as described above. [Pg.143]

The use of a continuous GPC viscosity detector in conjunction with a DRI detector permits the quantitative determination of absolute molecular weight distribution in polymers. Furthermore, from this combination one can obtain Mark-Houwink parameters and the bulk intrinsic viscosity of a given polymer with a GPC calibration curve based only on polystyrene standards. Coupling these two detectors with ultraviolet and infrared detectors then will permit the concurrent determination of polymer composition as a function of molecular weight and... [Pg.294]

C. 1 -Phenylcyclopentanecarboxaldehyde. The crude tetrahy-drooxazine (25.0 g., 0.092 mole) from Part B is heated at reflux with 300 ml. of water containing 37.8 g. (0.300 mole) of oxalic acid dihydrate for 3 hours. The solution is cooled, and the aldehyde is extracted with four 150-ml. portions of petroleum ether (b.p. 40-60°). The organic extracts are combined and washed with 10 ml. of saturated sodium bicarbonate solution and dried with anhydrous powdered magnesium sulfate. The petroleum ether is removed by distillation with a rotary evaporator, and the product is distilled through a Vigreux column to give 7.8-8.7 g. (50-55%) of 1-phenylcyclopentane-carboxaldehyde, b.p. 70-73° (0.1 mm.) n26-BD 1.5350, infrared spectrum (neat) 1720 cm.-1 (C= 0) (Note 12). [Pg.14]

The two phases are separated and the lower layer is extracted four times with 80-mL portions of hexane. The combined hexane solutions are washed with 40 mL of water and the hexane layer is separated and dried over Na2 S04, filtered under Ar, and cooled to — 78 °C. The separating crystals usually do not need further purification, their purity can be checked by infrared (IR)... [Pg.244]


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See also in sourсe #XX -- [ Pg.318 ]




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Drying combined

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