Aliphatic hydrocarbons production

Benzene, toluene and ethylbenzene Adiabatic turbulent flow reactor T = -1200 K 100 kPa t,cs = 0-125 ms = 0.3-1.5. Benzene and phenol and 7 other aliphatic hydrocarbon products identified (for benzene and ethylbenzene) 6 aromatics and 8 other aliphatic hydrocarbons identified (for toluene) as /(tres). 

Separation of Aromatic and Aliphatic Hydrocarbons. Aromatics extraction for aromatics production, treatment of jet fuel kerosene, and enrichment of gasoline fractions is one of the most important appHcations of solvent extraction. The various commercial processes are summarized in Table 4. 

Aliphatic Chemicals. The primary aliphatic hydrocarbons used in chemical manufacture are ethylene (qv), propjiene (qv), butadiene (qv), acetylene, and / -paraffins (see Hydrocarbons, acetylene). In order to be useflil as an intermediate, a hydrocarbon must have some reactivity. In practice, this means that those paraffins lighter than hexane have Httle use as intermediates. Table 5 gives 1991 production and sales from petroleum and natural gas. Information on uses of the C —C saturated hydrocarbons are available in the Hterature (see Hydrocarbons, C —C ). 

Dilute nitric acid can be used to oxidize an aliphatic hydrocarbon. For example, a significant use for nitric acid is the oxidation of cyclohexanol and cyclohexanone (qv) to produce adipic acid (qv). Most adipic acid is used for the production of nylon-6,6. 

Fluorination of aliphatic hydrocarbons with cobalt trifluoride gives complex mixtures Isobutane (2-methylpropane) fluorinated at 140-200 °C affords a mixture of 30 products of different degrees of fluorination and of isobutane as well as butane skeletons. The tertiary hydrogen is replaced preferentially Products containing 5-10 atoms of fluorine including a small amount of perfluoroisobutane were isolated [10]. 

Nitrosyl chloride reacts with aliphatic hydrocarbons at room temperature under the influence of light to give a complex mixture of substitution products. When the reaction is run on cyclohexane at —25°, however, the pure oxime hydrochloride crystallizes from the reaction mixture with virtually no side products. 

A further difficulty arises during preparative electrolyses in aprotic solvents because of the bulk pH change which commonly occurs. Thus cathodic reductions often require proton abstraction from the solvent in order to yield stable products, while many anodic oxidations, mcluding those of aromatic and aliphatic hydrocarbons, give rise to a quantitative yield of proton and the consequent changes in the pH. of the electrolysis media would be expected to lead to a variation in the products with the duration of the electrolysis. Unfortunately, the pH can be a very difficult parameter to control in aprotic solvents and most work reported in the literature has been carried out in unbuffered conditions. In the case of oxidations, organic bases, e.g. pyridine, have... 

The oxidation by Cr(VI) of aliphatic hydrocarbons containing a tertiary carbon atom has been studied by several groups of workers. Sager and Bradley showed that oxidation of triethylmethane yields triethylcarbinol as the primary product with a primary kinetic isotope effect of about 1.6 (later corrected by Wiberg and Foster to 3.1) for deuterium substitution at the tertiary C-H bond. Oxidations... 

Considerable attention has been directed in determining the products from reactions of aliphatic hydrocarbons, aromatic compounds, and unsaturated compounds including biogenic terpenes that exhibit appreciable volatility. These studies have been conducted both in simulation chambers and using natural sunlight in the presence of NO. 

Contaminants in recycled plastic packaging waste (HDPE, PP) were identified by MAE followed by GC-MS analysis [290]. Fragrance and flavour constituents from first usage were detected. Recycled material also contained aliphatic hydrocarbons, branched alkanes and alkenes, which are also found in virgin resins at similar concentration levels. Moreover, aromatic hydrocarbons, probably derived from additives, were found. Postconsumer PET was also analysed by Soxhlet extraction and GC-MS most of the extracted compounds (30) were thermally degraded products of additives and polymers, whereas only a few derived from the original contents... 

Wastes from the production of certain chlorinated aliphatic hydrocarbons (F024, F025)... 

Wastes from the Production of Certain Chlorinated Aliphatic Hydrocarbons... 

Wastes from the production of certain chlorinated aliphatic hydrocarbons listings designate as hazardous certain wastestreams produced in the manufacture of chlorinated aliphatic hydrocarbons. These listings stand out on the F list (the list of wastes from nonspecific sources), because... 

Arylsulphonyl nitrenes usually give better yields of hydrogen-abstraction products from aliphatic hydrocarbons. -Toluenesulphonyl azide gave a 5% yield of -toluenesulphonamide on thermolysis in cyclohexane... 

The spray paint can was inverted and a small amount of product was dispensed into a 20 mL glass headspace vial. The vial was immediately sealed and was incubated at 80°C for approximately 30 min. After this isothermal hold, a 0.5-mL portion of the headspace was injected into the GC/MS system. The GC-MS total ion chromatogram of the paint solvent mixture headspace is shown in Figure 15. Numerous solvent peaks were detected and identified via mass spectral library searching. The retention times, approximate percentages, and tentative identifications are shown in Table 8 for the solvent peaks. These peak identifications are considered tentative, as they are based solely on the library search. The mass spectral library search is often unable to differentiate with a high degree of confidence between positional isomers of branched aliphatic hydrocarbons or cycloaliphatic hydrocarbons. Therefore, the peak identifications in Table 8 may not be correct in all cases as to the exact isomer present (e.g., 1,2,3-cyclohexane versus 1,2,4-cyclohexane). However, the class of compound (cyclic versus branched versus linear aliphatic) and the total number of carbon atoms in the molecule should be correct for the majority of peaks. 

Further isomerization reactions may occur with alkyl-substituted aromatic reaction products, and a considerable study has been made of the reactions of this type of molecule. The following are the main types of skeletal reactions involving alkyl substituents on an aromatic ring (a) If the substituent chain is sufficiently large, there may occur within it all of the processes we have already discussed for aliphatic hydrocarbons them-... 

It must be stressed that a liquid component can be substituted with an efficient absorber of microwave irradiation together with a low-melting component. The use of most typical PTC solvents (nonpolar aromatic or aliphatic hydrocarbons, or highly chlorinated hydrocarbons) is most interesting for microwave activation, because such solvents are transparent or absorb microwaves only weakly. They can, therefore, enable specific absorption of microwave irradiation by the reagents, and the results or product distributions might be different under microwave and conventional conditions [7]. 

A similar mechanism of chain oxidation of olefinic hydrocarbons was observed experimentally by Bolland and Gee [53] in 1946 after a detailed study of the kinetics of the oxidation of nonsaturated compounds. Miller and Mayo [54] studied the oxidation of styrene and found that this reaction is in essence the chain copolymerization of styrene and dioxygen with production of polymeric peroxide. Rust [55] observed dihydroperoxide formation in his study of the oxidation of branched aliphatic hydrocarbons and treated this fact as the result of intramolecular isomerization of peroxyl radicals. 

A very serious problem was to clear up the formation of hydroperoxides as the primary product of the oxidation of a linear aliphatic hydrocarbon. Paraffins can be oxidized by dioxygen at an elevated temperature (more than 400 K). In addition, the formed secondary hydroperoxides are easily decomposed. As a result, the products of hydroperoxide decomposition are formed at low conversion of hydrocarbon. The question of the role of hydroperoxide among the products of hydrocarbon oxidation has been specially studied on the basis of decane oxidation [82]. The kinetics of the formation of hydroperoxide and other products of oxidation in oxidized decane at 413 K was studied. In addition, the kinetics of hydroperoxide decomposition in the oxidized decane was also studied. The comparison of the rates of hydroperoxide decomposition and formation other products (alcohol, ketones, and acids) proved that practically all these products were formed due to hydroperoxide decomposition. Small amounts of alcohols and ketones were found to be formed in parallel with ROOH. Their formation was explained on the basis of the disproportionation of peroxide radicals in parallel with the reaction R02 + RH. 

When a molecule consists of a few similar fragments n, the rate constant of the reactant reaction with this molecule can be expressed as the product of the partial rate constants ky k = nx kj. This was proved many times for free radical reactions for groups of reactants where both reactants or one of them are nonpolar. For example, the rate constants of peroxyl radical reactions with nonbranched aliphatic hydrocarbons Me(CH2) Me can be presented in... 

The sulfoxidation of aliphatic hydrocarbons is the easiest method for the synthesis of alkylsulfonic acids. Their sodium salts are widely used as surfactive reactants in technology and housekeeping. Platz and Schimmelschmidt [1] were the first to invent this synthetic method. Normal paraffins (Ci4-Cig) are used for the industrial production of alkylsulfonic acids [2-4]. Olefins and alkylaromatic hydrocarbons do not produce sulfonic acids under the action of sulfur dioxide and dioxygen and retard the sulfoxidation of alkanes [5-9],... 

Several factors indicate that the amino acids detected in all of these carbonaceous chondrites are indigenous and that they must have originated abiotically. First, the presence of protein and non-protein amino acids, with approximately equal quantities of D and L enantiomers points to a nonbiological origin and precludes terrestrial contamination. In addition, the non-extractable fraction of the Murchison is significantly heavier in 13C than terrestrial samples. Finally, the relative abundances of some compounds detected resemble those of products formed in prebiotic synthesis experiments. The aliphatic hydrocarbons are randomly distributed in chain length, and the C2, C3, and C4 amino acids have the highest concentrations (i.e., the most easily synthesized amino acids with the least number of possible structures are most abundant) [4]. 

Fischer-Tropsch A process for converting synthesis gas (a mixture of carbon monoxide and hydrogen) to liquid fuels. Modified versions were known as the Synol and Synthol processes. The process is operated under pressure at 200 to 350°C, over a catalyst. Several different catalyst systems have been used at different periods, notably iron-zinc oxide, nickel-thoria on kieselgtihr, cobalt-thoria on kieselgiihr, and cemented iron oxide. The main products are C5-Cn aliphatic hydrocarbons the aromatics content can be varied by varying the process conditions. The basic reaction was discovered in 1923 by F. Fischer and... 

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