Liquid whole crudes

Feedstocks for various industrial pyrolysis units are natural gas liquids (ethane, propane, and n-butane) and heavier petroleum materials such as naphthas, gas oils, or even whole crude oils. In the United States, ethane and propane are the favored feedstocks due, in large part, to the availability of relatively cheap natural gas in Canada and the Arctic regions of North America this natural gas contains significant amounts of ethane and propane. Europe has lesser amounts of ethane and propane naphthas obtained from petroleum crude oil are favored in much of Europe. The prices of natural gas and crude oil influence the choice of the feedstock, operating conditions, and selection of a specific pyrolysis system. 

Important analyses for the whole crude are as follows, including a liquid chromatographic separation adapted from the published SARA procedure (Saturates-Aromatics-Resins-Asphaltenes) for isolation of seven classes of compounds from mid-distillate (9). 

RVP is measurement of the volatility of a liquid hydrocarbon. Normally this is performed by ASTM D 323. This measurement is normally used to predict gasoline performance, normally expressed in pounds per square inch (psi). This is normally an inspection that is performed on Whole Crudes having relatively high API s. 

D. Overflash will be set at 2.0 vol. percent of whole crude feed. It will overflow from the first tray above the flash zone and, together with the feed-flash liquid, will fall to the residuum stripping section. 

In a 1-litre three-necked flask, fitted with a mechanical stirrer, reflux condenser and a thermometer, place 200 g. of iodoform and half of a sodium arsenite solution, prepared from 54-5 g. of A.R. arsenious oxide, 107 g. of A.R. sodium hydroxide and 520 ml. of water. Start the stirrer and heat the flask until the thermometer reads 60-65° maintain the mixture at this temperature during the whole reaction (1). Run in the remainder of the sodium arsenite solution during the course of 15 minutes, and keep the reaction mixture at 60-65° for 1 hour in order to complete the reaction. AUow to cool to about 40-45° (2) and filter with suction from the small amount of solid impurities. Separate the lower layer from the filtrate, dry it with anhydrous calcium chloride, and distil the crude methylene iodide (131 g. this crude product is satisfactory for most purposes) under diminished pressure. Practically all passes over as a light straw-coloured (sometimes brown) liquid at 80°/25 mm. it melts at 6°. Some of the colour may be removed by shaking with silver powder. The small dark residue in the flask solidifies on cooling. 

Benzyl cyanide (40 g. = 0 33 mole) is heated in a round-bottomed flask (capacity 0-5 1.), with a mixture of 50 c.c. of concentrated sulphuric acid and 30 c.c. of water. The flask is provided with an upright air condenser, and is placed in a conical (Babo) air bath. The heating is continued until the appearance of small bubbles of vapour indicates that a reaction, which rapidly becomes violent, has set in the liquid boils up, and white fumes are emitted. It is allowed to cool and then two volumes of water are added. After some time the phenylacetic acid which has crystallised out is filtered off with suction. If a sample of the material does not form a clear solution with sodium carbonate in water (presence of phenylacetamide), the whole of the crude material is shaken with sodium carbonate solution and the mixture is filtered. From the clear filtrate phenylacetic acid is reprecipitated with sulphuric acid, and can be recrystallised directly from a rather large volume of hot water or, after drying, from petrol ether. Because of its low melting point (76°) it often separates at first as an oil, but it can also be conveniently purified by distillation in vacuo from a sausage flask.2... 

Synthesis of compound A.A solution of 1,3-dibromopropane (10.1 g, 0.05 mol) in benzene (100 mL) was added to a solution of sodium telluride (NajTe 17.4 g, 0.1 mol) in ethanol (700 mL). After 3 h sodium borohydride (3.8 g, 0.1 mol) was further added to the mixture to produce sodium propane-1,3-ditellurolate, and then to the mixture was added a solution of the dibromopropane (10.1 g, 0.05 mol) in benzene (100 mL). The whole mixtnre was stirred at room temperature for 2 h. After usual work-up, the crude products were purified by silica gel column chromatography (eluent n-hexane/benzene) to afford compound A, which was further purified by preparative liquid chromatography. 

---