F Ethylbenzene

Ethyl 2-(2-amino-4-thiazole)-2-methoxyiminoacetate, 2995b iV-Ethylaniline, 2989 Ethyl azide, 0868 Ethyl 2-azido-2-propenoate, 1884 f Ethylbenzene, 2963 f Ethyl bromide, see Bromoethane, 0842... 

The reaction of HBpin in toluene in the presence of RhCl P(/-Pr)3 2(N2) (1 mol%) at 140 °C resulted in a mixture of (borylmethyl)benzene (69%) and bis(boryl)methyl benzene (7%), along with several products arising from aromatic C-H borylation (ca. 15%).345 Rhodium-bpy complexes catalyzed the borylation at the benzylic C-H bond.351 Pd/C was found to be a unique catalyst for selective benzylic C-H borylation of alkylbenzenes by B2pin2 or HBpin (Equation (70)).360 Toluene, xylenes, and mesitylene were all viable substrates however, the reaction can be strongly retarded by the presence of heteroatom functionalities such as MeO and F. Ethylbenzene resulted in a 3 1 mixture of pinacol 1-phenylethylboron and 2-phenylethylboron derivatives. 

A chromatographic process for separation of Cg aromatic isomers has been recently developed by Asahi. The process operates in the liquid phase and is put forward as an alternative to the UOP Sorbex process (see Section 12.5). The adsorbent is an A or T zeolite but details of the ionic form have not been released. A schematic of the process, which uses three separation columns, is shown in Figure 10.6. The main column separates the mixed-feed stream into four cuts containing (a) ortho + meta + ethylbenzene (trace), (b) ortho + meta -f ethylbenzene + paraxylene (trace), (c) paraxylene + ethylenebenzene, and (d) pure paraxylene. Cut (d) is passed directly to product while cut (b) is returned to the isomerization unit. Cuts (a) and (c) are passed to further columns in order to produce essentially pure ethylbenzene and paraxylene as products. 

The rate-based model gave a distillate with 0.023 mol % ethylbenzene and 0.0003 mol % styrene, and a bottoms product with essentially no methanol and 0.008 mol % toluene. Miirphree tray efficiencies for toluene, styrene, and ethylbenzene varied somewhat from tray to tray, but were confined mainly between 86 and 93 percent. Methanol tray efficiencies varied widely, mainly from 19 to 105 percent, with high values in the rectifying section and low values in the stripping section. Temperature differences between vapor and liquid phases leaving a tray were not larger than 5 F. 

Ethylbenzene is separated from mixed xylenes by fractionation using 360 trays and a high reflux ratio. Ethylbenzene is separated from the closest isomer paraxylene whose normal boiling point is only 3.90°F higher. The average relative volatility between ethylbenzene and paraxylene in the fractionation is about 1.06. The fractionator feed is entirely Cg aromatics which are prepared by the extraction of powerformate by the sulfolane process and by fractionation of the aromatic extract. 

Ethylbenzene is dehydrogenated to styrene over a fixed bed of catalyst and in the presence of a large excess of steam at 1150-1200°F and 1 atmosphere. 

The greater steric hindrance to acetylation was also shown by a comparison of the rate of (103At2) of acetylation of toluene (0.763), ethylbenzene (0.660), i-propylbenzene (0.606) and f-butylbenzene (0.462) with those (determined by the competition method) for benzoylation both sets of data (Table 112) were obtained with dichloroethane as solvent at 25 °C, all reagent concentrations being 0.1 A/421. Relative rates of acylation other aromatics under the same conditions have also been obtained and are given in Table 113422. The different steric requirements for acetylation and benzoylation are further shown by the following respective relative rates for acylation of naphthalene derivatives in chloroform at 0 °C naphthalene (1 position) 1.00,1.00, (2 position) 0.31,0.04 2,3-dimethylnaphthalene (1 position) 1.59, 172, (5 position) 7.14, 38.2, (6 position) 3.68, 7.7422a. 

Kniemeyer O, T Fischer, H Wilkes, FO Gldckner, F Widdel (2003) Anaerobic degradation of ethylbenzene by a new type of marine sulfate-reducing bacterium. Appl Environ Microbiol 69 760-768. 

Rabus R, M Kube, A Beck, F Widdel, R Reinhardt (2002) Genes involved in the anaerobic degradation of ethylbenzene in a denitrifying bacterium, strain EbNl. Arch Microbiol 178 506-516. 

Rabus R, F Widdel (1995) Anaerobic degradation of ethylbenzene and other aromatic hydrocarbons by new denitrifying hacter m. Arch Microbiol 163 96-103. 

Pyrolysis of ethylbenzene was carried out at 950 F in a flow reactor (Rase Kirk, Chem Eng Prog 30 35, 1954) with the tabulated data of fractional conversion at two pressures against W/F g catalyst/(gmol feed/hr). Find the fractional conversion at P = 1.5 and W/F = 25. 

Peng F, Fu X, Yu H, Wang H (2007). Preparation of carbon nanotube-supported Fe203 catalysts and their catalytic activities for ethylbenzene dehydrogenation. New Carbon Mater. 22 213-217. 

One method (EPA 8020) that is suitable for volatile aromatic compounds is often referred to as benzene-toluene-ethylbenzene-xylene analysis, although the method includes other volatile aromatics. The method is similar to most volatile organic gas chromatographic methods. Sample preparation and introduction is typically by purge-and-trap analysis (EPA 5030). Some oxygenates, such as methyl-f-butyl ether (MTBE), are also detected by a photoionization detector, as well as olefins, branched alkanes, and cycloalkanes. 

Ortho-xylene can be separated by distillation ethylbenzene is only 3.9°F from para-xylene, but by using very tall, multitrayed distillation columns (200 feet high with 300 trays), it too can be separated fairly... 

The alpha-methyl styrene can be recovered as a product or catalytically treated with hydrogen and converted back to cumene for recycling. The acetophenone has some commercial use in pharmaceuticals and at one time was used to make ethylbenzene. A high purity phenol is sometimes made by a crystallization step, since phenol freezes at about 109°F. With alpha-methyl styrene recycled, the ultimate yield is about 97%. 

This indirect oxidation route takes two steps. In the first, a hydrocarbon, such as iso butane or ethylbenzene, is oxidized. The source of the oxygen is air. The reaction takes place just by mixing the ingredients and heating them to 250-300°F at 50 psi, producing a hydroperoxide. In the second step, the oxidized hydrocarbon reacts with propylene in a liquid phase and in the presence of a metal catalyst at 175-225°F and 550 psi to produce PO yields of better than 90%. The process flow is shown in Figure 11—3. 

National Toxicology Program Toxicology and Carcinogenesis Studies of Ethylbenzene in F 344/N Rats and B6C3F1 Mice (Inhalation Studies). Technical Report Series No 466. NIH Publ No 99-3956, US Department of Health and Human Services, pp 1-224, 1999... 

FIGURE 6.3 Molecular weight of polystyrene (PS) as a function of solvent and solvent concentration A = -butylmercaptan, B = carbon tetrabromide, C = carbon tetrachloride, D = o-cresol, E = p-cresol, F = m-cresol, G = phenol, H = s-ec-butylbenzene, 1 = cumene, J = ethylbenzene, K = chloroform, L = -heptant, M = toluene, N = benzene, where [S] = concentration of chain-transfer agent and [M] = concentration of styrene monomer. 

Recently, alkylation of alkyl aromatic hydrocarbons such as toluene, ethylbenzene, cumene, and xylenes with ethene, propene, and 1,2-diphenylethene was investigated by Kijenski et al. (245), who used superbasic K-MgO and K-AI2O3 catalysts at low temperature at atmospheric and elevated pressures. The reaction kinetics, EPR measurements of adsorbed intermediates, and the effects of poisoning determined by the radical trap TEMPO (2,2,6,6-tetramethyl-l-piperidinyloxyl, free radical) led the authors to conclude that sites are the catalytically active centers. To demonstrate the importance of strong one-electron donor sites (F ) for the alkylation and the inactivity of strong two-electron donor centers, the ethylation of cumene, ethylbenzene, and toluene was carried out with MgO-10%NaOH. On this catalyst, strong basic two-electron donor sites (27 33) were found, along... 

Materials. An H-ZSM-5 type zeolite (overall Si/Al = 33.5) was provided by DEGUSSA, Wolfgang, F.R.G. The well-shaped crystallites had an average size of 8.8 p x 5.2 p x 3.2 y. Pyridine, benzene and ethylbenzene were from MERCK, Darmstadt, F.R.G., spectroscopic grade, purified by distillation as well as repeated freeze-pump-thaw cycles and finally stored over highly activated 3A molecular sieve pellets. 

Transalkylation of ethylbenzene temperature Inside catalyst bed - 385-395 0 starting reagent- ethylbenzene WHSV to ethylbenzene - 3 f 4-3,6 h . ... 

Comparatively few values have been measured for liquid-phase co-oxidations of hydrocarbon mixtures. With the exception of the cumene-Tetralin system, the reported values are all surprisingly low even for other systems giving tertiary and secondary (or primary) peroxy radicals. For example, at 60°C. values of 0.7 (36) and 1.3 (4) have been reported for the co-oxidation of cumene and ethylbenzene kt = 2.0 X 107 at 30°C. (14)], and a value of 1.4 (2) has been reported for the co-oxidation of cumene and 1-hexene [which gives mainly primary peroxy radicals with kt probably 1.3 X 108 at 30°C. (15)]. The confirmation that the present work provides for a relatively large value in the cumene-Tetralin system suggests that the other > systems deserve a close and careful reinvestigation. 

---