Hydrocarbons dissolved light

This procedure is a modification of that published by Pearson et al. A l.S-L two-necked flask equipped with a reflux condenser, magnetic stirrer bar, and surrounded by aluminum foil (to minimize exposure to light) is charged with trimethyl phosphate (Aldrich) (1 L) and dessicator dried (P2Oj) tri-tert-butyl-benzene (Aldrich) (76 g, 0.3 mol). The mixture is then stirred and warmed to 8S°C by means of an oil bath until the hydrocarbon dissolves. The temperature is lowered to 70 °C and bromine (56 g, 18 mL, 0.35 mol) is added rapidly. 

Waters. As mentioned previously, most hydrocarbons dissolved in water associated with crude oils or light refined products, such as gasoline and diesel fuels, have less than 10 carbon atoms in the molecule. This is... 

In general, the sulfolane extraction unit consists of four basic parts extractor, extractive stripper, extract recovery column, and water—wash tower. The hydrocarbon feed is first contacted with sulfolane in the extractor, where the aromatics and some light nonaromatics dissolve in the sulfolane. The rich solvent then passes to the extractive stripper where the light nonaromatics are stripped. The bottom stream, which consists of sulfolane and aromatic components, and which at this point is essentiaHy free of nonaromatics, enters the recovery column where the aromatics are removed. The sulfolane is returned to the extractor. The non aromatic raffinate obtained initially from the extractor is contacted with water in the wash tower to remove dissolved sulfolane, which is subsequently recovered in the extract recovery column. Benzene and toluene recoveries in the process are routinely greater than 99%, and xylene recoveries exceed 95%. 

Liquid products are withdrawn from plates 9, 16, and 22 as sidestreams. These are contacted with steam in external stripping columns having 4 to 6 plates in order to remove light dissolved hydrocarbons. Since the liquid withdrawn from any plate in a pipe still is in equilibrium with all the lighter vapor passing that plate, it always will contain material which is lower in boiling point than the desired product. 

Basically, a gas absorption tower is a unit in which the desirable light ends components are recovered from the gas feed by dissolving them in a liquid passing through the tower countercurrently to the gas. The liquid absorbent is called lean, oil, and it usually consists of a hydrocarbon fraction in the gasoline boiling range. After the absorption step, the liquid which now contains the desired constituents in solution is referred to as fat oil. A similarly descriptive nomenclature is applied to the gas, which is referred to as wet gas when it enters the tower and as dry gas when it leaves the absorber. 

Natural gas is a naturally occurring mixture of light hydrocarbons accompanied by some non-hydrocarbon compounds. Non-associated natural gas is found in reservoirs containing no oil (dry wells). Associated gas, on the other hand, is present in contact with and/or dissolved in crude oil and is coproduced with it. The principal component of most... 

Degassed water under ambient conditions has a relaxation time (T and T2) of about 4 s at 30 °C [11,12], However, air-saturated brines may have a relaxation time of about 2-3 s. Light hydrocarbons are even more sensitive to dissolved oxygen [10], For example, the relaxation time of deoxygenated pentane is 14 s while air-saturated pentane is about 3 s. The correlation for degassed alkanes between the relaxation time (Ti), viscosity (q) and temperature (T) is given by Eq. (3.6.1) [13]. 

Myristic acid (from decanoic acid and methyl hydrogen adipate). Dissolve 55-2 g. of pure decanoic acid (capric acid decoic acid), m.p. 31-32°, and 25 -6 g. of methyl hydrogen adipate in 200 ml. of absolute methanol to which 0-25 g. of sodium has been added. Electrolyse at 2-0 amps, at 25-35° until the pH of the electrolyte is 8-2 (ca. 9 hours). Neutralise the contents of the electrolytic cell with acetic acid, distil off the methanol on a water bath, dissolve the residue in about 200 ml. of ether, wash with three 50 ml. portions of saturated sodium bicarbonate solution, and remove the ether on a water bath. Treat the residue with a solution of 8 0 g. of sodium hydroxide in 200 ml. of 80 per cent, methanol, reflux for 2 hours, and distil off the methanol on a water bath. Add about 600 ml. of water to the residue to dissolve the mixture of sodium salts extract the hydrocarbon with four 50 ml. portions of ether, and dry the combined ethereal extracts with anhydrous magnesium sulphate. After removal of the ether, 23-1 g. of almost pure n-octadecane, m.p. 23-24°, remains. Acidify the aqueous solution with concentrated hydrochloric acid (ca. 25 ml.), cool to 0°, filter off the mixture of acids, wash well with cold water and dry in a vacuum desiccator. The yield of the mixture of sebacic and myristic acids, m.p. 52-67°, is 26 g. Separate the mixture by extraction with six 50 ml. portions of almost boiling light petroleum, b.p. 40-60°. The residue (5 2 g.), m.p. 132°, is sebacic acid. Evaporation of the solvent gives 20 g. of myristic acid, m.p. 52-53° the m.p. is raised slightly upon recrystallisation from methanol. 

Commercial Examples. The small but often undesirable contents of water dissolved in hydrocarbons may be removed by distillation. In drying benzene, for instance, the water is removed overhead in the azeotrope, and the residual benzene becomes dry enough for processing such as chlorination for which the presence of water is harmful. The benzene phase from the condenser is refluxed to the tower. Water can be removed from heavy liquids by addition of some light hydrocarbon which then is cooked out of the liquid as an azeotrope containing the water content of the original heavy liquid. Such a scheme also is applicable to the breaking of aqueous emulsions in crude oils from tar sands. After the water is removed... 

The iodide is a pure white crystalline solid which is sensitive to light and moisture, Heating it with silver powder in vacuo at 280°C produces SiaI and silver iodide. The compound dissolves without reaction in dry hydrocarbons. 

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