Petroleum sources

Within the VGO saturates, distribution of paraffins, isoparaffins, and naphthenes is highly dependent on the petroleum source. The naphthenes account for roughly 60% of the saturates in a normal cmde oil. However, samples can be found having paraffins from <20 to >80%. In most samples, the / -paraffins from C2Q—are still present in sufficient quantity to be detected as distinct peaks in gc analyses. Some cmde oils show a nearly symmetric pattern of peaks such that each carbon number is present in regular progression up to a maximum around C -j. Other cmde oils show a similar distribution, but have preference for odd-numbered alkanes. Both the distribution and the selectivity toward odd-numbered hydrocarbons are considered to reflect differences in petrogenesis of the cmde oils. Although / -paraffins are distinct in the gc, these usually account for only a few percent of the saturates measured by gc. 

After 1950, benzene in motor fuel was largely replaced by tetraethyllead but the demand for benzene in the chemical industry persisted and soon exceeded the total production by the coal carbonization industry. To meet this growing demand, methods for producing benzene directiy from petroleum sources were developed. 

The pattern of commercial production of 1,3-butadiene parallels the overall development of the petrochemical industry. Since its discovery via pyrolysis of various organic materials, butadiene has been manufactured from acetylene as weU as ethanol, both via butanediols (1,3- and 1,4-) as intermediates (see Acetylene-DERIVED chemicals). On a global basis, the importance of these processes has decreased substantially because of the increasing production of butadiene from petroleum sources. China and India stiU convert ethanol to butadiene using the two-step process while Poland and the former USSR use a one-step process (229,230). In the past butadiene also was produced by the dehydrogenation of / -butane and oxydehydrogenation of / -butenes. However, butadiene is now primarily produced as a by-product in the steam cracking of hydrocarbon streams to produce ethylene. Except under market dislocation situations, butadiene is almost exclusively manufactured by this process in the United States, Western Europe, and Japan. 

Carboxylic acids having 6—24 carbon atoms are commonly known as fatty acids. Shorter-chain acids, such as formic, acetic, and propionic acid, are not classified as fatty acids and are produced synthetically from petroleum sources (see Acetic acid Formic acid and derivatives Oxo process). Fatty acids are produced primarily from natural fats and oils through a series of unit operations. Clay bleaching and acid washing are sometimes also included with the above operations in the manufacture of fatty acids for the removal of impurities prior to subsequent processing. 

With each succeeding year in the 1950s and 1960s there was a swing away from coal and vegetable sources of raw materials towards petroleum. Today such products as terephthalic acid, styrene, benzene, formaldehyde, vinyl acetate and acrylonitrile are produced from petroleum sources. Large industrial concerns that had been built on acetylene chemistry became based on petrochemicals whilst coal tar is no longer an indispensable source of aromatics. 

Synthesis gas consists of a nonhydrocarhon mixture (H2,CO) ohtain-ahle from more than one source. It is included in this chapter and is further noted in Chapter 5 in relation to methane as a major feedstock for this mixture. This chapter discusses the use of synthesis gas obtained from coal gasification and from different petroleum sources for producing gaseous as well as liquid hydrocarbons (Fischer Tropsch synthesis). 

Biodegradable polymers are polymers that imdergo microbially induced chain scission leading to mineralization. Biodegradable polymers may not been produced from bio-source only, but it can be derived from the petroleum source (Ray and Bousmina, 2005). Efforts... 

The highly aromatic resins are often used as coumarone/indene resin substitutes. A range of soft aromatic resins is available, produced from the alkylation of xylene and other aromatic hydrocarbons with dicyclopentadiene. These are excellent softeners for a wide range of rubbers. In common with other aromatic materials derived from petroleum sources, some of the resins used within the rubber industry are deemed to be carcinogenic. 

In the last years, the replacement of gasoline with other new fuels became a priority because of unavoidable depletion of natural petroleum sources. 

Generally, dissolved aromatics may be found quite far from the origin of a spill, but entrained hydrocarbons may be found in water close to the petroleum source. Oxygenates such as methyl-f-butyl ether (MTBE) are even more water soluble than aromatics and are highly mobile in the environment. 

The Cio fraction in reformates has been considered a likely petroleum source for obtaining durene (9). However, there are 28 kinds of isomeric arenes in the fraction, and the durene content is only 5-9%. Therefore, the isolation of durene from such a complicated mixture is inefficient, and some complicated techniques are required for it. In contrast, 1,2,4-trimethyl-benzene (pseudocumene) can be easily isolated simply by the distillation of the Cg fraction of the reformates, and a high-purity pseudocumene has been produced on an industrial scale. 

Algal sources are ice algae, diatoms, cyanobacteria, dinoflagellates, and picoplankton petroleum sources include eroded bitumens, oil seeps, etc. 

The chemical composition of vapors and fumes from asphalt products is variable and depends on the crude petroleum source, type of asphalt, temperature, and extent of mixing. Therefore, the adverse effects from asphalt may also vary considerably depending on the source of exposure. 

Another near future objective is to ensure development of technology that enables production of motor-fuel substitutes fhom non petroleum sources. The production of methanol-higher alcohols mixtures fhom natural gas,via syngas, remains a priority objective to obtain octane boosters capable of replacing lead alkyls and to allow the use of additional low-priced methanol. 

Aquatic seeds in irrigation ditches interfere with the flow of water and often result in serious loss to farmers. Chlorinated benzene with appropriate emulsion stabilizers has proved effective in the control of such weeds. The Bureau of Reclamation through its Denver laboratories tested methyl substituted benzenes and found them equally toxic to aquatic weeds. As a result, the aromatic solvents, both from coal and petroleum sources, are proving a boon to farmers. 

The oil embargo of 1973-74 caused the Federal Highway Administration (FHWA) to establish an R D program to investigate the production of asphalt replacements and extenders from essentially non-petroleum sources. Since its inception, this program has examined in detail the use of sulfur in elemental and chemically modified form binders derived from cellulosic materials such as wood wastes and animal manure (JL) and lignins produced as by products of the paper and pulp industries (2) ... 

A fourth type of petroleum isomerization, which was commercialized on a small scale, involves the rearrangement of naphthenes. In the manufacture of toluene by dehydrogenation of methylcyclohexane, the toluene yield can be increased by isomerizing to methylcyclohexane the dimethylcyclopentanes also present in the naphtha feed. This type of isomerization is also of interest in connection with the manufacture of benzene from petroleum sources. 

I here is much evidence (1) that naturally occurring asphalts were valued for their cementitiousness, inertness, and waterproofing qualities as early as 3800 B.C. But it is only since they became readily available from petroleum sources that asphalts have been widely used on a large scale. The first modern asphalt pavements were constructed about 1852 near Paris, France, of a rock asphalt mastic (8). From 1870 to 1876 several pavements, using rock asphalts and Trinidad lake asphalt were laid in eastern cities of the United States (5). The demand for such pavements was relatively small and was filled by natural asphalts imported from Trinidad and Bermudez lakes during the next 35 years. 

Prior to this time, other ventures had already been operating to produce commercial quantities of aliphatic chemicals from petroleum sources. Truly commercial production of ethylene glycol had been achieved by 1925 (10) using natural gas fractions as a starting material, and even earlier (about 1920) there had been the manufacture of isopropyl alcohol from cracking plant propylene (20), which may be termed the pioneer operation on a successful, continuing basis in the sphere of aliphatic synthesis from petroleum. 

An interesting case of interproduct competition is that of the four original lacquer solvents—ethyl alcohol, butyl alcohol, ethyl acetate, and butyl acetate. These were once produced mainly by fermentation processes, but today all are also produced by synthesis from petroleum hydrocarbons. Moreover, in the past 30 years solvents have been developed from petroleum sources which are competing successfully with these materials even though the new compounds are not identical in all properties isopropyl alcohol competes with ethyl alcohol methyl isobutyl carbinol and n-propyl alcohol can replace butyl alcohol methyl ethyl ketone to a large extent supplants ethyl acetate and methyl isobutyl ketone can be substituted for butyl acetate. Thus, petroleum aliphatic chemicals have served both by displacement of source and replacement of end product to supplement and to compete with the fermentation solvents. 

T he petroleum industry entered the field of aromatics production largely because the unprecedented demand for toluene for the manufacture of TNT at the outbreak of World War II in 1939 could not be met by other sources. As a result of its efforts, the industry supplied 75 to 85% of all the toluene which was nitrated for TNT production during the latter years of World War II. Since that time the petroleum refiners have remained in the field and at present they are major suppliers of toluene and xylenes. In Table I it is shown that in 1949 about 59% of the toluene and 84% of the xylenes produced in the United States were derived from petroleum sources. The petroleum industry has diversified its operations in the field of aromatics production until at present a variety of materials is offered. Table II presents a partial list of the commercially available aromatics, together with some of their uses. A number of other aromatics, such as methylethyl-benzene and trimethylbenzene, have been separated in small scale lots both as mixtures and as pure compounds. 

Toluene, total Petroleum sources All other sources... 

Despite the fact that formaldehyde is the minor ingredient in the production of these resins and that only part of the formaldehyde is presently derived from petroleum sources, the production of formaldehyde from petroleum feed stocks is already an industrial process of considerable volume and one that promises to be of increasing future interest to the petroleum industry. 

Another group of potentially large volume plastics that is under development are the polysulfone resins, made by the copolymerization of olefins such as 1-butene with sulfur dioxide 24). Both these feed stocks could be derived in abundant quantities and at relatively low costs from petroleum sources. The polysulfone resins are moldable thermoplastic polymers having physical properties that vary widely depending on the olefin from which they are prepared. They are considered to have excellent prospects for development to a large volume, low cost commercial plastic and may permit the entrance of plastic products into other fields in which they are now limited by the high cost and inadequate supply of present thermoplastic materials. 

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