Petroleum crude and distillate

Analysis of Petroleum Crude and Distillates by Gel Permeation Chromatography... 

Petroleum crude and its refinery products have two major component based on distillation. The portion that can be distilled under refinery conditions can be called volatiles and the nondistillables are the nonvolatiles. The volatiles can be analyzed by GC or GC-MS. The crude has both components. The distillate as the names applied, such as naphtha and kerosene contain only volatiles. When GPC is used for analyzing various distillates, the fractions separated by GPC can be characterized by GC or GC-MS. These data can be used to verify the nature of components present in various distillation cuts as a function of GPC elution volume. If the samples such as crude contains both volatiles as well as nonvolatiles, the samples should be separated into volatiles and nonvolatiles. The GPC of both components should be used to calibrate the GPC of the total crude. The parameter that can be obtained from GPC is effective molecular length. It can be used to relate other molecular parameters of interest after calibration. 

Coal liquids, petroleum crudes, and their distillation cuts have been separated into four or five fractions by SEC (5 15). The SEC fractions were analyzed by use of GC. The procedure was performed manually. It was inefficient, and susceptible to human error. The automated fraction collection followed by injection of the fraction into the GC reduces analysis time, and offers an option for collection of the desired number of fractions at predetermined time intervals. The manual collection of up to 10 one-ml fractions is also used in order to study the effectiveness of the automated method. 

The following is a modification of the process described and gives quite satisfactory results. Wash the crude mixture of benzonitrile and dibromopentane with sodium carbonate solution until the latter remains alkaline, and then with water. Distil it under reduced pressure and collect the fraction boiling up to 120°/18 mm. Dissolve this in twice its volume of light petroleum, b.p. 40-60°, which has previously been shaken with small volumes of concentrated sulphuric acid until the acid remains colourless. Shake the solution with 6 per cent, of its volume of concentrated sulphuric acid, allow to settle, and run ofi the sulphuric acid layer repeat the extraction until the acid is colourless or almost colourless. Wash successively with water, sodium carbonate solution and water, dry over anhydrous calcium chloride or calcium sulphate, and distil off the solvent. Distil the residue under diminished pressure and collect the 1 6-dibromopentane at 98- 100°/13 mm. 

The cooled mixture is transferred to a 3-1. separatory funnel, and the ethylene dichloride layer is removed. The aqueous phase is extracted three times with a total of about 500 ml. of ether. The ether and ethylene chloride solutions are combined and washed with three 100-ml. portions of saturated aqueous sodium carbonate solution, which is added cautiously at first to avoid too rapid evolution of carbon dioxide. The non-aqueous solution is then dried over anhydrous sodium carbonate, the solvents are distilled, and the remaining liquid is transferred to a Claisen flask and distilled from an oil bath under reduced pressure (Note 5). The aldehyde boils at 78° at 2 mm. there is very little fore-run and very little residue. The yield of crude 2-pyrrolealdehyde is 85-90 g. (89-95%), as an almost water-white liquid which soon crystallizes. A sample dried on a clay plate melts at 35 0°. The crude product is purified by dissolving in boiling petroleum ether (b.p. 40-60°), in the ratio of 1 g. of crude 2-pyrrolealdehyde to 25 ml. of solvent, and cooling the solution slowly to room temperature, followed by refrigeration for a few hours. The pure aldehyde is obtained from the crude in approximately 85% recovery. The over-all yield from pyrrole is 78-79% of pure 2-pyrrolealdehyde, m.p. 44 5°. 

Raw petroleum (crude oil) is extracted from underground around the globe in a variety of ways and refined for tens of thousands of applications in our everyday lives. Crude oil is refined into usable petroleum products through several unique processes. Fractional distillation is the process used to efficiently extract or "distill" products that are a mixture of chemicals such as gasoline, diesel fuel, and kerosene or may selectively extract pure chemical compounds or petrochemicals such as... 

The reaction mixture was removed from the vessel and distilled at a pressure of 30-60 mm, and a bath temperature of 30°C to 50°C until the methanol had all been removed. The extremely viscous tarry residue remaining in the still pot was given a very crude distillation, the distillate boiling at B2°C to 1 32°C/2 mm. In an attempt to purify this distillate by a more careful distillation, 5.3 g of a liquid distilling from 53°C to 150°C/5 mm was collected. At this point, much solid sublimate was noted not only in this distillate but in the condenser of the still. 7 g of the solid sublimate was scraped out of the condenser of the still. Recrystallization of the sublimate from ethyl acetate containing a small amount of petroleum ether gave beautiful crystals melting at 175°C to 177°C (5 g). Infrared analysis confirmed that this compound was hydroquinone (9% conversion). 

Natural gas and crude oils are the main sources for hydrocarbon intermediates or secondary raw materials for the production of petrochemicals. From natural gas, ethane and LPG are recovered for use as intermediates in the production of olefins and diolefms. Important chemicals such as methanol and ammonia are also based on methane via synthesis gas. On the other hand, refinery gases from different crude oil processing schemes are important sources for olefins and LPG. Crude oil distillates and residues are precursors for olefins and aromatics via cracking and reforming processes. This chapter reviews the properties of the different hydrocarbon intermediates—paraffins, olefins, diolefms, and aromatics. Petroleum fractions and residues as mixtures of different hydrocarbon classes and hydrocarbon derivatives are discussed separately at the end of the chapter. 

To a stirred solution of 5.70g (21.1 mmol) of 4,4.5,5-tetramethyl-2[(5)-(A)-3-(trimethylsilyloxy)-l-bulenyl]-l, 3,2-dioxaborolane in 130 mL of petroleum ether (bp 40-60 C) are added ca. 20 mg of cobalt(II) nitrate hexahydrale followed immediately by 2.75 g (23.1 mmol) of freshly distilled thionyl chloride. Slow evolution of sulfur dioxide ceases after 4h. The mixture is then filtered and concentrated in vacuo at r.t. to give crude 15, which is taken up in 50 mL of petroleum ether and washed with 30-mL portions of buffer (pH 5) until the pH is constant. 100 mL of brine are added to the organic phase and the pH is adjusted to 7 by addition of sat. aq NaHCO,. The pH should not exceed 7, otherwise decomposition ensues. The phases are separated and the organic phase is dried with MgS04 and concentrated at r.t. to give 15 yield 4.39 g (96%) Contact of 15 with metal surfaces should be avoided. 

O Brien Explosives. A series of patents were issued to J.F. O Brien of Chicago, HI, USA between 1913 and 1915 for new commercial expls. Typical formulations included K chlorate 30, Nitrostarch 10, Si dioxide 55, crude petroleum with coal dust 5ps (Ref 1) K chlorate 87, naphthalene 6.5, asphalt 6.5, crude oil distillate 1.5 Si dioxide 44ps (Ref 2) K chlorate with Na nitrate 60, Hq TNT 15 sawdust 25p (Ref 3) and Amm perchlorate 20—65, Na nitrate 55, liq DNT 10—15, sawdust 14-23 free C l-3.5ps (Ref 4)... 

One particularly important case of distillation sequencing is worthy of special consideration. This is the case of crude oil distillation, which is the fundamental process underlying the petroleum and petrochemicals industry. Crude oil is an extremely complex mixture of hydrocarbons... 

At the end of the heating period the contents of the flask will have solidified. To the cold mixture 40 ml. of water is added to hydrolyze the potassium methoxide and precipitate the pyrimidine the fine crystals are filtered and dried. The crude product is placed in a 500-ml. distilling flask with 250 ml. of purified kerosene (Note 3). On distilling the kerosene, the pyrimidine codistils and solidifies in the receiving flask to a snow-white mass of crystals. These are filtered, washed well with petroleum ether, and dried in an oven at 100°. The yield of pure material, melting at 182-183°, is 27.5-28.7 g. (67-70%) (Note 4). 

When the mixture has cooled sometvhat, 75 to 100 cc. of absolute alcohol is added. After all the particles of sodium have reacted, 500 cc. of water is added, the condenser is arranged for downward distillation, and the benzene and unchanged />-chlorobiphenyl are removed by distillation from a steam bath (Note 7). The crude product remaining in the flask is separated by filtration, washed with 100-200 cc. of water, and pressed as dry as possible. The solid is dissolved in 600 cc. of xylene in a 1-1. distilling flask, and the solution is subjected to distillation until 25 to 50 cc. of distillate (xylene and water) has been collected. The solution is cooled somewhat, 1 to 2 g. Norite is added, and then the mixture is boiled for five minutes. The hot solution is filtered rapidly and the filtrate is cooled. The product is collected by filtration, washed with 25 to 50 cc. of cold xylene then with 200 cc. of petroleum ether, and dried. The tribiphenylcarbinol forms small white crystals which melt at 207-208°. The product weighs 57-65 g. (35-40 per cent of the theoretical amount) (Note 8). 

Pure xylan is not employed in industry. but crude xylan or pentosans are of industrial importance. Xylan has been proposed as a textile size but is not employed as yet for this purpose.130 Perhaps the largest use of pentosans is in their conversion to furfural, which has many applications and serves as the source of other furan derivatives. At the present time, large quantities of furfural are used in the extractive purification of petroleum products, and recently a large plant has been constructed to convert furfural by a series of reactions to adipic acid and hexamethylene-diamine, basic ingredients in the synthesis of nylon. In commercial furfural manufacture, rough ground corn cobs are subjected to steam distillation in the presence of hydrochloric acid. As mentioned above, direct preferential hydrolysis of the pentosan in cobs or other pentosan-bearing products could be used for the commercial manufacture of D-xylose. 

Dispersants are being increasingly used to combat oil spills in the marine environment. The new generation of dispersants are commonly fatty acid-polyethoxylate esters (25) and are relatively non toxic. The specific compounds in petroleum responsible for MFO induction in fish have not been defined. Dispersed oil could increase the availability of inducing components, either the particulates or solubles, but alternatively, soluble compounds may be rapidly lost from dispersed oil (26). Preliminary experiments have been carried out to assess the effectiveness of dispersed oil in AHH induction. Venezuelan crude and bunker (distillation cut above 300-400°C).and two polyethoxylate oil spill dispersants,... 

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