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Phenols crude

Palo, R. T., Sunnerheim, K., and Theander, 0.(1985). Seasonal variation of phenols, crude protein and cell wall content of birch Betulapendula Roth.) in relation to ruminant in vitro digestibility. Oecohgia 65,314—318. [Pg.497]

As for distillation procedures, numerous conventional methods have become known which are concerned with particular mixtures, such as the determination of the boiling behaviour of phenol crude acids. A rapid analysis for petrols up to 180 °C... [Pg.34]

The treated water containing sodium chloride, cyanides, phenols and traces of H2S and NH3 is recycled to the crude desalting unit and used as wash water for the hydrotreaters and FCC units. [Pg.405]

The method can be used to determine the amount of a known alcohol or phenol present in a crude sample, provided that the impurities do not themselves contain hydroxyl groups. [Pg.452]

Concentrate the mother liquors from this recrystallisation and combine with the oily filtrate dissolve in 250 ml. of 10 per cent, sodium hydroxide solution, and extract with two 50 ml. portions of ether to remove non-phenolic products. Acidify the alkaline solution with hydrochloric acid, separate the oily layer, dry it over anhydrous magnesium sulphate, and distil under diminished pressure, preferably from a Claisen flask with fractionating side arm (Figs. II, 24, 2-5). Collect the o-propiophenol (65 g.) at 110-115°/6 mm. and a further quantity (20 g.) of crude p-propiophenol at 140-150°/ 1 mm. [Pg.676]

Dissolve 5 g. of phenol in 75 ml. of 10 per cent, sodium hydroxide solution contained in a wide-mouthed reagent bottle or conical flask of about 200 ml. capacity. Add 11 g. (9 ml.) of redistilled benzoyl chloride, cork the vessel securely, and shake the mixture vigorously for 15-20 minutes. At the end of this period the reaction is usually practically complete and a sohd product is obtained. Filter oflf the soUd ester with suction, break up any lumps on the filter, wash thoroughly with water and drain well. RecrystaUise the crude ester from rectified (or methylated) spirit use a quantity of hot solvent approximately twice the minimum volume required for complete solution in order to ensure that the ester does not separate until the temperature of the solution has fallen below the melting point of phenyl benzoate. Filter the hot solution, if necessary, through a hot water funnel or through a Buchner funnel preheated by the filtration of some boiling solvent. Colourless crystals of phenyl benzoate, m.p. 69°, are thus obtained. The yield is 8 g. [Pg.784]

Phenolsulphonephthalein (phenol red). Mix 10 g. of o-sulpho-benzoic anhydride (Section VIII,9), 14 g. of pure phenol and 10 g. of freshly fused zinc chloride in a small conical flask. Place a glass rod in the flask and heat gently over a flame to melt the phenol. Then heat the flask containing the well-stirred mixture in an oil bath at 135-140° for 4 hours. Stir from time to time, but more frequently during the first hour if the mixture froths unduly, remove the flask from the bath, cool and then resume the heating. When the reaction is complete, add 50 ml. of water, allow the water to boil and stir to disintegrate the product. Filter the crude dye with suction and wash it well with hot water. Dissolve the residue in the minimum volume of warm (60°) 20 per cent, sodium hydroxide solution, filter, and just acidify the filtrate with warm dilute hydrochloric acid (1 1). Filter the warm solution, wash with water, and dry upon filter paper. The yield of phenol red (a brilliant red powder) is 11 g. [Pg.990]

Unexpectedly, a completely different reaction took place in the oxidation of 2-(l-propenyl)phenol (111) with PdCh. Carpanone (112) was obtained in one step in 62% crude yield. This remarkable reaction is explained by the formation of o-quinone, followed by the radical coupling of the side-chain. Then the intramolecular cycloaddition takes place to form carpanone[131]. [Pg.36]

Floripavidine, CjjHjgOjN. This occurs in the crude mixture of non-phenolic bases, and is separated from fioribundine by repeated crystallisation of the mixed hydrochlorides from water. The base crystallises from alcohol in prisms, has m.p. 241-2°, and [a]n — 156-25° (MeOH) the hydrochloride, m.p. 209-10°, hydriodide, and methiodide, m.p. 228-30°, were prepared. The alkaloid contains no hydroxyl group (Zerewitinoff), but a methoxyl, a dioxymethylene, and a methylimino group are present. [Pg.276]

A mixture of 10 g of 4-(2, 4 -difluorophenyl)-phenol and 27.2 g of potassium carbonate is exposed to carbon dioxide at 1,300 psi and 175°C. The dark mass obtained from this car-donation is then dissolved in 300 ml of water and 200 ml of methylene chloride and the two layers separated. The water layer is then extracted with 100 ml of methylene chloride and then acidified with 2.5 N hydrochloric acid. This mixture is then filtered and the cake dried in vacuo to yield 5.32 g of the crude product. The crude product is then recrystallized from benzene-methanol. An additional crystallization of this semipure material from benzene-methanol yields analytically pure 2-hydroxy-5-(2, 4 -difluorophenyl)-benzoic acid (MP 210°-211°C). [Pg.490]

Oxygen compounds in crude oils are more complex than the sulfur types. However, their presence in petroleum streams is not poisonous to processing catalysts. Many of the oxygen compounds found in crude oils are weakly acidic. They are carboxylic acids, cresylic acid, phenol, and naphthenic acid. Naphthenic acids are mainly cyclopentane and cyclohexane derivatives having a carboxyalkyl side chain. [Pg.17]

Cresylic acid is a commercial mixture of phenolic compounds including phenol, cresols, and xylenols. This mixture varies widely according to its source. Properties of phenol, cresols, and xylenols are shown in Table 4-5 Cresylic acid constitutes part of the oxygen compounds found in crudes that are concentrated in the naphtha fraction obtained principally from naphthenic and asphaltic-based crudes. Phenolic compounds, which are weak acids, are extracted with relatively strong aqueous caustic solutions. [Pg.131]

A solution of phenol (188 mg, 2 mmol) and benzonitrile (2.06 g, 20 mmol) in McCN (20 mL) was degassed by bubbling nitrogen through it and irradiated with a 16-W low-pressure mercury arc lamp (Applied Photophysics Ltd, APQ40) for 24h. The crude product was separated by flash chromatography (EtOAc/ petroleum ether 1 5) to give yellow crystals yield 79 mg (20%) mp 53-55 C. [Pg.513]

This procedure provides a convenient method for the esterification ol a wide variety of carboxylic acids. The reaction proceeds smoothly with sterically hindered acids6 and with acids which contain various functional groups. Esters are obtained in high purity using Kugelrohr distillation as the sole purification technique. In cases where traces of dichloromethane present no problems, the crude product is usually pure enough to be used directly in subsequent reactions. Methyl and ethyl ethers of phenols may also be prepared by this procedure (see Note 8). [Pg.62]

The total anthocyanin content can often be determined in crude extracts containing other phenolic materials by measuring absorptivity of the solution at a single wavelength (Table 6.3.1). This is possible because anthocyanins have typical absorption bands in the 490 to 550 nm region of the visible spectra — far from the absorption bands of other phenolics with spectral maxima in the UV range. ... [Pg.483]

Watermelon cell walls, prepared as follows, were kindly provided by Dr. Niels O. Maness of the Department of Horticulture and Landscape Architecture of Oklahoma State University. Ripe watermelon mesocarp tissues were placed on ice, diced into small pieces, and then homogenized on ice in Tris-saturated phenol to give enzymically inactive watermelon cell walls [6]. The solids were collected on two layers of mira cloth and washed with water until the smell of phenol was gone. The crude cell walls were further washed with chloroform methanol (1 1, W/V) and acetone until a fluffy consistency was obtained. The acetone-washed cell wall residue was dried in an oven at 60 °C and stored in a brown bottle. [Pg.80]

Certain alkyl-substituted phenol-formaldehyde resins can act as dispersants for asphalts and asphaltenes in crude oils [1681]. The dispersants help keep asphalt and asphaltenes in dispersion and inhibit fouling, precipitation, and buildup in the equipment. [Pg.315]

A process for separating crude oil emulsions of the water-in-oil type based on certain ethylene oxide-propylene oxide block pol5miers and certain poly-glycidol ethers of phenol-formaldehyde-condensation products has been described [1026-1028]. [Pg.332]

H. Diaz-Arauzo. Phenolic resins and method for breaking crude oil emulsions. Patent US 5460750,1995. [Pg.379]


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See also in sourсe #XX -- [ Pg.257 ]




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