Naphtha synthetic

Since 1960, about 95% of the synthetic ammonia made in the United States has been made from natural gas worldwide the proportion is about 85%. Most of the balance is made from naphtha and other petroleum Hquids. Relatively small amounts of ammonia are made from hydrogen recovered from coke oven and refinery gases, from electrolysis of salt solutions, eg, caustic chlorine production, and by electrolysis of water. In addition there are about 20 ammonia plants worldwide that use coal as a hydrogen source. 

Acetic acid (qv) can be produced synthetically (methanol carbonylation, acetaldehyde oxidation, butane/naphtha oxidation) or from natural sources (5). Oxygen is added to propylene to make acrolein, which is further oxidized to acryHc acid (see Acrylic acid and derivatives). An alternative method adds carbon monoxide and/or water to acetylene (6). Benzoic acid (qv) is made by oxidizing toluene in the presence of a cobalt catalyst (7). 

The cleavage of carbon-carbon o- bonds is the main reaction in thermal cracking of naphtha, one of the commonest processes in the hydrocarbon conversion industry. Thus, radical dissociation or cleavage of carbon-carbon cr bonds has been quite familiar to synthetic and physical organic chemists. 

Liquid Petroleum Tar kerosene diesel petrol fuel oil synthetic LPG gasoline naphtha pitch... 

Gasynthan A process for making synthetic natural gas from naphtha by a two-stage steam reforming process. Developed by Lurgi and BASF in the 1960s. In 1975, over 30 units were operating. 

Consecutively, the heavy paraffins are cracked into lighter hydrocarbon fractions by hydro-cracking. For example, for the Shell Middle Distillate Synthesis (SMDS) process, the liquid product stream is composed of 60% gasoil (diesel), 25% kerosene and 15% naphtha. The gaseous product mainly consists of LPG (a mixture of propane and butane) (Eilers et al., 1990). Figure 7.3 shows a simplified diagram comprising all process steps to produce synthetic hydrocarbons from biomass, natural gas and coal. 

Introduction of zeolites into catalytic cracking improved the quality of the product and the efficiency of the process. It was estimated that this modification in catalyst composition in the United States alone saved over 200 million barrels of crude oil in 1977. The use of bimetallic catalysts in reforming of naphthas, a basic process for the production of high-octane gasoline and petrochemicals, resulted in great improvement in the catalytic performance of the process, and in considerable extension of catalyst life. New catalytic approaches to the development of synthetic fuels are being unveiled. 

Synthesis gas can easily be confused with the oxymoron synthetic natural gas, SNG. Both are sometimes called "syngas." But SNG is basically methane made from petroleum products, like naphtha or propane, or from coal. It s used as a substitute for or supplement to natural gas. 

With the development of 2-D chromatography, direct hydrocarbon speciation in the LCO range for synthetic crudes produced in FCC laboratory reactors became possible. The new method in addition to a greater understanding of the mid-distillate chemical composition avoided the effect of variations in light naphtha condensation efficiency on total aromatics. The C5 + fraction lost to the gas phase will concentrate aromatics in the liquid phase and numerical compensation by adding the gas phase C5s back to the liquid phase and is subject to errors because of the low precision of C5 + determination in the gas phase. 

We will examine three synthetic fuel scenarios and compare their implications regarding sulfur availability with the current and projected market for sulfur to the year 2000. The analysis will consider three production levels of synthetic fuels from coal and oil shale. A low sulfur Western coal will be utilized as a feedstock for indirect liquefaction producing both synthetic natural gas and refined liquid fuels. A high sulfur Eastern coal will be converted to naphtha and syncrude via the H-Coal direct liquefaction process. Standard retorting of a Colorado shale, followed by refining of the crude shale oil, will round out the analysis. Insights will be developed from the displacement of imported oil by synthetic liquid fuels from coal and shale. 

We will consider three processes in more detail to show how the sulfur in the original feedstock material (coal or oil shale) is recovered as elemental by-product sulfur. In this way yields of sulfur per barrel of product can be computed. The three processes will illustrate examples of coal gasification for production of SNG, methanol or indirect liquids, direct liquefaction for production of naphtha and synthetic crude oil and finally, oil shale retorting for production of hydrotreated shale oil. 

The plant will process 27,836 TPSD of Illinois No. 6 high sulfur bituminous coal containing 4.45 wt% sulfur on an as recieved basis. The output of fuel products form the plant is 15,531 BPSD of naphtha and 51,325 BPSD of syncrude. 1,178 tons per day of elemental sulfur is produced. This represents 95 wt% of the total input sulfur in the feedstock coal. Most of the remaining sulfur is still present in the liquid synthetic crude oil. From the available data for this proposed plant, the output of elemental sulfur is calculated to be 0.0176 tons per product barrel. Since a high sulfur coal was used this represents a high sulfur production case as it is likely that direct liquefaction facilities will use high sulfur Eastern bituminous coals as feedstock. 

The new Brownsville, Tex., plant for the manufacture of synthetic liquid fuels from natural gas makes use of this reaction to increase the octane number of its product by as much as 20 units. Synthetic naphtha produced over iron catalyst is highly olefinic and contains substantial amounts of straight-chain isomers with terminal double bonds (8). The shifting of these double bonds toward the center of the molecule may be accomplished by vapor-phase treatment employing synthetic cracking catalyst in the fluid state, under mild catalytic cracking conditions. Oxygenated compounds also present are converted under the isomerization conditions to hydrocarbons and water. 

Exposure to isoprene occurs in the production of the monomer and in the production of synthetic rubbers. Isoprene occurs in the environment due to emissions from vegetation and the production of ethylene by naphtha cracking. 

Double-bond isomerization was once used in the multistep synthesis of isoprene developed by Goodyear.266-268 2-Methyl-1-pentene produced by the dimerization of propylene was isomerized to 2-methyl-2-pentene over a silica-alumina catalyst at 100°C. The product was cracked to isoprene and methane. Because of the lower cost of isoprene isolated from naphtha or gas oil-cracking streams, synthetic isoprene processes presently are not practiced commercially. 

Until the mid-1970s metal-catalyzed propylene dimerization had practical significance in isoprene manufacture. Goodyear developed a process to dimerize propylene in the presence of tri-n-propylaluminum to yield 2-methyl-1-pentene.16,95,96 This was then isomerized to 2-methyl-2-pentene followed by cracking into isoprene and methane. This and other synthetic pocesses, however, are no longer practiced since they are not competitive with isoprene manufactured by cracking of naphtha or gas oil. 

A number of years ago. coal tar was the primary, if not the sole, source lor hundreds of important organic chemicals and derivatives, notably the phenols, cresols, naphthalene, and anthracene, as well as other important coal lar end-prralucls, such as solvent naphtha and pitch. In recent years, synthetic processes Tor the production of phenol, the cresols and later the xylcnols. have been developed and thus, to a large extent, have pushed coal lar into the background as a source of feedstocks for (he chemical industry. 

Fuel natural gus. naphtha Natural gas. synthetic nalural gas. light petroleum disiillales medium-Blu gas and methanol with additional equipment... 

The synthetic crude was produced by hydrogenating the IBP-350°F naphtha, the 350°-550°F light oil, and the 550°-850°F heavy oil fractions obtained from in situ crude shale oil by distillation followed by coking of the 850°F-f- residuum. Characterization of the syncrude was accomplished by examining the following fractions CB-175°F light naphtha, 175°-350°F heavy naphtha, 350°-550°F light oil, and 550°-850°F heavy oil. 

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