Oil slate

Approximately 5 000 naturally abundant acyclic and cyclic diterpenes derived from the parent hydrocarbon phytane are known The (3i ,7i ,ll )-enantiomer of phy-tane has been found in meteorites, oil slate, other sediments and, last but not least, in human liver. Oil slate additionally eontains (-)-(3if,7if,llif)-phytanoic acid which has also been isolated from butter. 1,3(20)-Phytadiene is one among many constituents of tobacco Nicotiana tabacum (Solanaceae) -1,3-phytadiene and its (%)-isomer are found in zooplankton. Chlorophyll in the chloroplasts of plant cells exemplifies an ester of +)-(lE,lR, l/ )-2-phyten-l-ol usually referred to as phytol. 2,6,10,14-Phytatetraene-l,19-diol, better known as plaunotol, is the ehief constituent of the leaves of flie Thai medicinal plant Croton sublyratus (Euphorbiaceae) used as "plau noi" or "kelnac" as an antiulcerative. 

Stereoisomers of hopane as the parent hydroearbon of about 100 naturally abundant hopane triterpenes are isolated in small amounts from oil slate and petroleum of various provenanee. Hydroxylated hopanes sueh as (-l-)-6a,22-hopanediol are found to oeeur in some liehens and, assoeiated with (-l-)-22(29)-hopen-6a,2ip-diol, in the roots of Iris missouriensis (Liliaeeae). Neohopanes exemplified by (-l-)-12-neo-hopen-3p-ol from Rhododendron linearifolium (Erieaeeae) rarely oeeur as natural produets. 

Baeteriohopane-32,33,34,35-tetrol and other bio-hopanes partially substituting eho-lesterol in the eell walls of baeteria isolated from eulture eontain an unbranehed polyhydroxylated Cs-Ce aUcyl ehain attaehed to C-30 of the hopane skeleton. Following the death of the baeteria, the hydroxy funetions of bio-hopanes are redueed geo-hopanes whieh are isolated in large amounts from oil slate and other sediments were probably ereated via this pathway some 500 million years ago. 

Small amounts of the dextrorotatory parent hydrocarbon of the ten naturally abundant gammaceranes have been extracted from oil slate. 3-Hydroxy-derivatives such as (+)-16-gammacerene-3p-ol are constituents of the roots of bitter herb Picris hieracioides (Asteraceae). 22p-Hydroxy-30-nor-gammaceran-21-one is found in the Japanese fern Adiantum monochlamys. 

Properties. Shell s two-step SMDS technology allows for process dexibiUty and varied product slates. The Hquid product obtained consists of naphtha, kerosene, and gas oil in ratios from 15 25 60 to 25 50 25, depending on process conditions. Of particular note are the high quaHty gas oil and kerosene. Table 2 gives SMDS product quaHties for these fractions. 

Refinery Production. Refinery propylene is formed as a by-product of fluid catalytic cracking of gas oils and, to a far lesser extent, of thermal processes, eg, coking. The total amount of propylene produced depends on the mix of these processes and the specific refinery product slate. For example, in the United States, refiners have maximized gasoline production. This results in a higher level of propylene production than in Europe, where proportionally more heating oil is produced. 

Steam Cracking. Steam cracking is a nonselective process that produces many products from a variety of feedstocks by free-radical reactions. An excellent treatise on the fundamentals of manufacturing ethylene has been given (44). Eeedstocks range from ethane on the light end to heavy vacuum gas oil on the heavy end. All produce the same product slate but in different amounts depending on the feedstock. 

The H-Coal process could operate in one of two modes, depending on the desired product slate. In the "syn-cmde" mode, a fluid-bed coking unit was employed to maximize recovery of distillate from the Hquefaction product (Fig. 7a). When operated in the fuel oil mode (Fig. 7b), no coker was used and the primary product was a coal-derived low sulfur fuel oil. Total hydrogen demand on the process was also reduced in the latter mode of operation. 

These data for typical properties of EP polymers are either as measured or as advertised by respective manufacturers. This table is not intended to be definitive either in terms of the total grade slate or the specific data reported for each producer. Note that the molecular weight distribution data are based on a qualitative comparison of GPC curves. Mooney viscosities are repotted for final product form (i.e.. in the case of oil-extended rubbers, the viscosity is that of the EP plus oil. 

Specimen F waa said to have bccu obtained Irom old and young leaves and to have been adulterated with kiiroseut. and therefore to he -of no use to the dealer price 200. When lironght into water, this oil formed a compact mass with a thick aurlace, partly of a whitish and striped appearance. (Ailour rather dark. The dealer slated that hft bad showed us this oil only as a specimuii of adulterated oil, that bo kept it ouly as a sample, and thai be had only a small amount of it, Conseqnently he could only sell us such a Small sample. 

Tafel-bl, n. salad oil, esp. olive oil. -paraffin, n. cake paraffin, -quarz, m. tabular quarts, -salz, n. table salt, -schiefer, m. roofing slate slate in slabs school slate, -schmiere, /. table grease, -spat, m. tabular spar, wol-lastonite. -wa(a)ge, /. counter scales platform scales, -wasser, n. table water, drinking water, -wein, m. table wine. 

Superficially the Oryx GTL refinery design has much in common with the SMDS process, but there are important differences. There is no separate hydrotreater, which limits production of chemicals, such as waxes. The hydrocracker employs the Chevron Isocracking technology, which is based on a sulfided supported base-metal catalyst that was designed for crude oil conversion. The operating conditions of the hydrocracker are also more severe (>350°C, 7 MPa) than those required by the SMDS process (300-350°C, 3-5 MPa). Only intermediate products are produced (Table 18.13),5 with the naphtha slated as cracker feed and the distillate as blending component for diesel fuel. 

The selection of crude oil type is critical to the design and economic success of a crude oil refinery. Different crude oil types require a different refining strategy, and depending on the crude oil type, it may be easier or more difficult to achieve a specific product slate. The product slate is often determined by regional markets, unless the products are specifically earmarked for export. This also holds true for Fischer-Tropsch syncrude. 

---